What Is a Duplex Ultrasound? Vascular Surgeon Explains

Duplex ultrasound combines an image of a blood vessel with information about the blood flowing through it. Ultrasound provides the picture; Doppler assesses movement and flow. Together, they help us investigate problems affecting arteries and veins.

In this video, I explain why a duplex scan is frequently used for varicose veins, leg swelling, blocked arteries and possible blood clots. Understanding what the test measures can make a scan appointment less unfamiliar and help you understand the next steps in your care.

What does the ultrasound part show?

Ultrasound uses high-frequency sound waves. A probe sends these waves into the body and receives the echoes that return from tissues. The machine converts those echoes into an image.

For a vascular scan, this helps show the vessel and the structures around it. The person performing the scan can examine a particular area and take measurements relevant to the clinical question.

What does Doppler add?

Doppler uses changes in reflected sound waves to assess moving blood. It provides information about the direction and speed of flow, which can be displayed as colours or waveforms and sometimes heard as a sound.

This matters because a vessel’s appearance is only part of the story. I also need to understand whether blood is passing through effectively, whether flow is altered by narrowing, or whether it is moving backwards through a vein. Duplex brings the image and flow assessment together.

Which circulation problems can a duplex scan investigate?

• Varicose veins and venous reflux: identifying backward flow and mapping affected veins when assessing venous symptoms.

• Possible blood clots: examining the deep veins when deep vein thrombosis (DVT) is suspected.

• Narrowed or blocked arteries: assessing blood flow in people with symptoms that may relate to peripheral arterial disease.

• Treatment planning or follow-up: providing information that may guide a procedure or help assess circulation afterwards.

The scan is tailored to the reason for referral. An examination for venous reflux is not identical to an arterial scan or a scan for suspected DVT. Explaining your symptoms clearly helps ensure the assessment answers the relevant question.

What happens during the scan?

Usually, gel is applied to the skin and a handheld probe is moved over the area being examined. You may be asked to change position so the vessels can be assessed properly. The area needs to be accessible, so comfortable clothing can be helpful.

A standard external duplex scan is non-invasive and does not use ionising radiation. You may hear the machine’s blood-flow sounds during the examination. Let the sonographer know if an area is painful or if you have difficulty standing or changing position.

Preparation and appointment length depend on the vessels being examined. Follow the instructions supplied by the clinic rather than assuming every ultrasound appointment has the same requirements.

Does a scan result tell the whole story?

No single investigation replaces a clinical assessment. I interpret the findings alongside your symptoms, examination and medical history. Sometimes duplex provides the information needed; sometimes further tests or another form of imaging are appropriate.

Useful questions to ask include: What was the scan looking for? What did it show? Does the finding explain my symptoms? What should happen next? The aim is to connect the result to a clear care plan, rather than leave you with an unfamiliar technical term.

The vascular ultrasound guide explains different scan types, preparation, limitations and how results guide care.

Duplex ultrasound assessment in Singapore

As I explain in the video, our practice has its own vascular laboratory and a dedicated vascular sonographer who focuses on vascular scans. For advice about an assessment, contact Andrew Choong Vascular Surgery at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

New one-sided painful leg swelling needs urgent assessment; do not wait for a routine scan appointment. Sudden breathlessness, chest pain or collapse requires emergency care. Call 995 in Singapore for a life-threatening emergency.

This article provides general education and does not replace an individual medical assessment.

EVAR for Aortic Aneurysms: A Pipe Within a Pipe

EVAR treats a suitable aortic aneurysm from inside the blood vessel using a stent graft. A useful way to picture it is a pipe within a pipe: blood flows through a new lining designed to reduce pressure on the weakened aneurysm wall.

In this video, I introduce endovascular aortic repair and explain why it has become an important option for some patients. It is less invasive than open repair, but the right choice depends on the aneurysm, your overall health and the need for long-term follow-up.

What is an aortic aneurysm?

The aorta is the body’s main artery. An aneurysm is an abnormal enlargement of part of that artery, associated with weakening of its wall. Many aneurysms cause no symptoms and are discovered during a scan performed for another reason or through screening.

The concern is rupture, which can cause life-threatening internal bleeding. However, finding an aneurysm does not automatically mean an operation is needed. Smaller aneurysms may be monitored, with decisions guided by their size, growth, symptoms and the balance of treatment risks. Read more about aortic aneurysms and aortic disease.

How does EVAR work?

During EVAR, a stent graft is introduced through the arteries in the groin and positioned inside the aorta using imaging guidance. Access may be through small punctures or small incisions, depending on the vessels and the planned procedure.

The graft has a supporting framework and a fabric covering. It forms a channel through which blood can flow, with seals above and below the aneurysm in suitable anatomy. The aneurysm remains outside the graft, so the operation does not simply remove the enlarged artery.

The aim is to exclude the aneurysm from the main blood flow and reduce its risk of rupture. Whether this can be achieved safely must be assessed before treatment.

The EVAR treatment guide explains assessment, risks, alternatives and recovery in more detail.

Who may be suitable for EVAR?

A CT scan helps the vascular team evaluate the aneurysm and plan a repair. Important considerations include:

• The aneurysm’s location and shape: including its relationship to important branch arteries.

• Suitable sealing areas: where the graft can fit securely.

• Access through the groin arteries: their size, narrowing and tortuosity can matter.

• Your overall health: including kidney function, fitness and other medical conditions.

• Long-term care: including the ability to attend follow-up scans.

Some aneurysms need a more complex endovascular approach or open surgery. For others, continued surveillance is appropriate. These decisions form part of individual treatment planning.

How does EVAR compare with open repair?

For suitable patients, EVAR can offer a less demanding early recovery and lower short-term operative risk than open repair. Those early benefits do not mean it is the best option for everyone or that the aneurysm requires no further attention.

Open repair remains important. The discussion includes the expected benefits, procedural risks, durability and likelihood of needing further treatment. I would explain why an option fits your particular anatomy and circumstances rather than choose solely by the size of the incision.

Why are follow-up scans important?

After EVAR, scans check the graft’s position and whether the aneurysm remains effectively excluded. One issue they look for is an endoleak, meaning blood still reaches the aneurysm sac outside the graft. Some findings require monitoring; others may need another procedure.

Follow-up is therefore part of the treatment, even when you feel well. The schedule and type of scan depend on the repair and subsequent findings.

Should you discuss aneurysm screening?

In the video, I encourage people with a family history, and men over 55 particularly with smoking or high blood pressure, to discuss their risk. This is an invitation to an individual assessment, not a universal screening rule for everyone over 55. Screening recommendations vary by age, sex, smoking history and family history.

Ultrasound can assess the abdominal aorta when screening is appropriate. Sudden severe abdominal or back pain, especially with collapse, needs emergency care instead of a screening appointment. In Singapore, call 995 for a life-threatening emergency.

Aortic aneurysm assessment in Singapore

To discuss a known aneurysm or your screening risk, contact Andrew Choong Vascular Surgery at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

This article provides general education and does not replace an individual medical assessment.

Why Do Some Foot and Leg Wounds Not Heal?

A foot or leg wound that is not healing may need more than a change of dressing. Wound healing depends on several things working together, including an adequate blood supply, controlled swelling, protection from pressure and appropriate management of infection and underlying health conditions.

In this video, I focus on two questions from a vascular perspective: is enough blood reaching the wound through the arteries, and are the veins draining effectively? These questions can help explain why a wound remains open despite regular care.

When is a wound considered chronic?

In the video, I describe a wound that persists beyond about four weeks as chronic. Definitions vary, and the important point is that a wound which is not progressing needs its underlying cause reviewed.

Four weeks is not a waiting period before seeking help. A new foot wound in someone with diabetes, a worsening wound or signs of infection deserves earlier assessment. Reduced sensation can make a significant wound surprisingly painless.

How can blocked arteries delay healing?

Arteries bring blood carrying oxygen and nutrients to the tissues. If they are narrowed or blocked, the wound may not receive enough blood to repair itself effectively. This is one reason peripheral arterial disease (PAD) matters in foot and leg wound care.

Some people also notice pain when walking, pain at rest or a foot that feels unusually cold. Others have fewer obvious symptoms, particularly if diabetes has affected their nerves. The wound’s appearance alone cannot establish whether the blood supply is adequate.

How can vein problems affect a wound?

Veins return blood from the legs towards the heart. When their one-way valves do not work properly, blood can flow backwards, a problem called venous reflux. Raised venous pressure and swelling can damage the surrounding skin and interfere with healing.

This is a different mechanism from arterial blockage. Someone with venous disease or varicose veins may also have ankle swelling, aching, brownish skin changes or a recurrent ulcer. Arterial and venous problems can occur together, so treatment should follow an assessment rather than an assumption.

What else can prevent a wound from healing?

Circulation is only part of the picture. Factors that may need attention include:

• Diabetes: including glucose control, nerve damage and infection risk.

• Pressure or repeated injury: for example, footwear rubbing the same area.

• Smoking and nutrition: both can affect the body’s ability to repair tissue.

• Medicines and other illnesses: these may influence healing and should be reviewed.

• Infection: which can worsen a wound and become more serious when blood supply is poor.

What does a vascular wound assessment involve?

I would ask how the wound started, how long it has been present and what care it has received. Examination includes the wound, surrounding skin, swelling and foot pulses. Your medical history and medicines help guide further investigation.

Tests may include ankle or toe pressure measurements and duplex ultrasound to assess arterial flow or venous reflux. Further imaging is selected according to the findings. Not every wound requires every test or a procedure.

A treatment plan may combine dressings, pressure relief, management of infection and diabetes, and treatment of a circulation problem where appropriate. Compression can help selected venous ulcers, but its suitability depends on the arterial blood supply. Avoid starting tight bandaging yourself.

The diabetic foot and vascular wound-care guide explains how circulation, infection treatment and pressure relief fit together.

Which changes need urgent attention?

Seek urgent medical help for spreading redness, increasing warmth or swelling, pus, worsening pain, fever or black tissue. A suddenly cold, painful, numb or weak foot needs emergency assessment. Do not wait for a routine clinic appointment if the problem is rapidly worsening; call 995 in Singapore for a life-threatening emergency.

Assessment for a non-healing wound in Singapore

For a wound that is slow to heal, contact Andrew Choong Vascular Surgery to discuss assessment at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Understanding the cause helps guide care beyond the dressing itself.

This article provides general education and does not replace an individual medical assessment.

When Is Leg Swelling Not Just Water Retention? 2 of 2

Leg swelling that builds towards evening may be related to venous reflux, but new swelling in one leg needs prompt attention. A red, hot, painful calf can occur with deep vein thrombosis, and a clot does not always cause every one of those signs. The safest next step depends on the pattern and timing of symptoms.

This is the second part of the series. Part one explains the different causes of leg swelling.

What can the timing of swelling tell us?

With venous reflux, leaking valves make it harder for blood to return efficiently from the legs. Gravity and long periods with little movement can increase pressure in the veins. Some people notice more swelling after standing, sitting or travelling, and less after resting with their legs elevated.

That pattern can support a discussion about venous disease, but it cannot confirm the cause. In particular, swelling after a long flight should not automatically be dismissed as familiar reflux. A new one-sided change deserves assessment even if you have had varicose veins for years.

Does improvement with compression prove that the veins are responsible?

No. Feeling better in compression stockings can be useful information for your clinician, but it is not a diagnostic test. It does not rule out a blood clot or another explanation for swelling.

Tell your doctor what you have tried and how symptoms responded. If compression is being considered, the appropriate type and fit should be assessed, including whether arterial circulation or other health conditions make it unsuitable. New symptoms should be evaluated rather than managed simply by choosing tighter stockings.

When should one-sided leg swelling be checked?

New unexplained swelling affecting one leg should be checked promptly, especially if accompanied by calf pain, warmth, redness or a change in skin colour. These findings can occur with deep vein thrombosis, often called DVT, but can also have other causes.

A DVT is a clot in a deep vein. The classic description of a red, hot, swollen calf is a useful warning, not a checklist that must be complete. The absence of dramatic redness or severe pain does not safely exclude a clot. A clinician needs to assess the symptoms and relevant risk factors.

Which symptoms mean I should call for emergency help?

Call 995 in Singapore for sudden breathlessness, chest pain, coughing up blood or collapse, particularly when there is also leg pain or swelling. These can be signs of a pulmonary embolism, where a clot has travelled to the lungs, or another serious emergency.

Do not wait for a routine vein appointment if these symptoms occur. The priority is urgent hospital assessment. Leg swelling alone and leg swelling with breathing symptoms require different levels of urgency.

How does a duplex ultrasound help?

A duplex ultrasound provides information about the veins and the blood moving through them. For suspected venous reflux, the examination can assess valve function and identify the veins involved. This helps link the symptoms to an anatomical problem and supports treatment planning.

When a clot is suspected, the assessment follows an urgent diagnostic pathway. The clinician considers the history and examination and may arrange ultrasound and blood tests as appropriate. A scan requested for chronic reflux should not be assumed to replace a timely assessment for new DVT symptoms.

What should I tell the clinician?

Explain exactly when the swelling began, whether one or both legs are affected and how it differs from your usual pattern. Mention recent surgery, a hospital stay, reduced mobility, travel, cancer treatment or a previous clot. Include medicines, including hormone treatments, in your medication list.

If the swelling has been recurring over weeks or months, describe whether it improves overnight and whether there are visible veins or skin changes. This helps distinguish the questions that need to be answered rather than treating all swelling as the same condition.

What happens after the cause is identified?

Care depends on the diagnosis. Confirmed venous reflux, DVT and non-vascular causes of swelling need different approaches. An ultrasound result may lead to advice, further investigation or a discussion of suitable treatment; it does not mean everyone needs a vein procedure. Read more about varicose veins and venous conditions.

Our guide to varicose veins, DVT and leg swelling brings together the related conditions and assessment pathways.

Where can I arrange a non-emergency assessment?

For persistent or recurring symptoms, contact Dr Andrew Choong’s clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Bring previous imaging and your medication list. For new one-sided swelling, seek prompt medical assessment; for chest or breathing symptoms, use emergency services.

This article provides general education and does not replace an individual medical assessment.

When Is Leg Swelling Not Just Water Retention? 1 of 2

Leg swelling is often described as “water retention”, but that phrase does not explain why it is happening. Fluid can accumulate in the legs for several different reasons, including problems affecting the whole body, an injury or difficulty returning blood through the veins. Identifying the cause is the first step towards an appropriate plan.

What does “water retention” actually mean?

Swelling caused by fluid collecting in the tissues is called oedema. It describes a physical finding rather than a complete diagnosis. Two people with similarly swollen ankles may have quite different underlying problems and need different investigations.

The useful next questions are when the swelling began, whether one or both legs are affected, and what else has changed. A label alone cannot answer those questions or establish whether the situation is routine or urgent.

Can a problem elsewhere in the body cause swollen legs?

Yes. Some causes are systemic, meaning they affect the body more broadly. Heart problems can increase pressure in the circulation and contribute to swelling. Kidney or liver conditions and disturbances in fluid or protein balance can also be relevant.

Certain medicines may contribute to ankle swelling as well. This is one reason a medication list is useful at an appointment. Do not stop prescribed medicines on your own: a clinician needs to consider the timing of symptoms, the reason for treatment and possible alternatives.

Swelling in both legs may prompt questions about general health, but it does not automatically mean a heart or kidney disorder. The distribution is one clue among several, rather than a diagnosis by itself.

What local problems can make a leg swell?

A local cause affects a particular area. An injury, inflammation around a joint or an infection can produce swelling. The history may include a twist, fall, painful joint, wound or a change in the skin, but sometimes the explanation is less obvious.

One leg becoming larger than the other deserves attention, especially when the change is new. A clinician will consider vascular and non-vascular possibilities. An assessment should not start with the assumption that all swelling is due to veins.

How does venous reflux contribute to swelling?

Leg veins return blood towards the heart. Their valves help keep flow moving in the intended direction. When valves do not work effectively, blood can flow backwards, a problem called venous reflux. The resulting pressure can contribute to fluid accumulating in the tissues.

This explains why a vein problem can create more than visible varicose veins. Heaviness, aching and swelling may be part of the same circulation issue. Read more about varicose veins and venous disease.

However, finding visible veins does not prove they explain every symptom. Vein disease can coexist with a joint problem, medication-related swelling or another medical condition. The assessment needs to consider the whole picture.

What information helps identify the cause?

Before a non-emergency appointment, note whether the swelling appeared suddenly or gradually, whether it changes over the day, and whether both legs are affected equally. Describe any pain, skin changes, breathlessness or recent illness.

Also mention recent travel, surgery, reduced mobility and any previous blood clot. Bring medication details and previous test results. These observations help the clinician decide whether a venous ultrasound, other investigations or a different specialist assessment is needed. They should not delay urgent care when warning signs are present.

When should swelling be checked urgently?

Seek prompt medical assessment for new unexplained swelling in one leg, especially if it is painful, red or warm. A deep vein thrombosis is one possible cause, although other conditions can look similar. Sudden breathlessness, chest pain or collapse requires emergency help: call 995 in Singapore.

Persistent or worsening swelling in both legs also warrants medical review. Treating the appearance of swelling without understanding its cause can miss a problem that needs a different approach.

Our guide to varicose veins, DVT and leg swelling brings together the related conditions and assessment pathways.

Where can I discuss persistent leg swelling in Singapore?

For a non-emergency vascular assessment, contact Dr Andrew Choong’s clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. The aim is to understand whether venous disease contributes to the swelling and what further assessment or care is appropriate.

This article provides general education and does not replace an individual medical assessment.

Why Varicose Veins Feel Worse at the End of the Day

Varicose veins can feel more uncomfortable after a long day because blood returning from the legs has to work against gravity. If vein valves leak and the calf muscles have been relatively inactive, pressure can build in the leg veins. Aching, heaviness and ankle swelling may therefore become more noticeable towards evening.

Why does gravity affect the veins in the legs?

Veins return blood towards the heart. In the legs, this means moving blood upwards for much of the day. One-way valves help limit backward flow, and the calf muscles act as a pump when you walk and move your ankles.

The return system works differently from the arteries, which carry blood away from the heart under higher pressure. Veins depend on the interaction between valves, muscles and body position. Long periods spent standing still or sitting with the feet down give the calf pump fewer opportunities to help.

What is venous reflux?

Venous reflux means blood flows backwards through valves that are not closing properly. Blood can collect in the veins and raise the pressure below those valves. Enlarged, twisted veins near the skin may become visible as varicose veins.

The visible veins are only part of the picture. The symptoms someone experiences depend on the underlying flow problem and other factors affecting the leg. You can learn more about varicose veins and venous circulation on our condition page.

Which symptoms may become worse by evening?

Venous symptoms can include heaviness, aching, tiredness, cramping and ankle swelling. Some people notice that their shoes feel tighter later in the day. Others describe a dragging discomfort after standing at work or sitting through a long journey.

A pattern that improves after walking or resting with the legs elevated can be useful information, but it does not prove that varicose veins are the cause. Muscle, joint, nerve and other medical conditions can produce overlapping symptoms. Persistent swelling deserves assessment rather than an assumption based on appearance alone.

Can movement and leg elevation help?

Regular walking and gentle ankle movement encourage the calf muscles to assist venous return. Breaking up long periods of stillness may help reduce the build-up of discomfort. Resting with the legs elevated can also ease symptoms for some people.

These measures may improve comfort, but they do not establish the diagnosis or necessarily correct leaking valves. If symptoms are increasing or affecting daily activities, an assessment can clarify whether a treatable vein problem is present.

Compression stockings may be considered in selected circumstances, but they need an appropriate fit and clinical advice. They are not suitable for everyone, particularly when arterial circulation is impaired, and should not replace an assessment of new or unexplained swelling.

What does a venous duplex ultrasound show?

A duplex ultrasound combines images of the veins with information about blood flow. In someone with suspected varicose vein disease, it can identify reflux and help map the veins involved. That makes it useful for confirming the problem and planning treatment.

The scan follows a clinical assessment. Your history, skin changes, swelling and any previous clot or vein treatment all help determine what needs to be examined. A scan result is interpreted alongside those findings rather than in isolation.

Does everyone with varicose veins need a procedure?

No. The decision depends on symptoms, complications, ultrasound findings and personal preferences. Options may include advice, monitoring or a procedure to treat an affected vein. When intervention is appropriate, the clinician can explain the benefits, limitations and recovery associated with the suitable options.

Changes around the ankle such as persistent itching, discolouration, fragile skin or a wound that is not healing are reasons to seek assessment. Varicose veins are not always just a cosmetic concern.

When should I seek urgent help?

Do not attribute sudden one-sided swelling, pain, redness or warmth to ordinary evening vein discomfort. Seek prompt medical assessment because deep vein thrombosis is one possible cause. If swelling is accompanied by chest pain, sudden breathlessness or collapse, call 995 in Singapore. Bleeding from a varicose vein also requires urgent attention.

Where can I arrange a vein assessment in Singapore?

Contact Dr Andrew Choong’s clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Bring previous ultrasound reports and note when the discomfort occurs, whether one or both legs are affected, and what helps. These details support a focused assessment and an individual care plan.

This article provides general education and does not replace an individual medical assessment.

Arteries vs Veins: What’s the Difference?

Arteries carry blood away from the heart, while veins return blood towards it. That simple distinction helps explain why different circulation problems can produce different patterns of leg pain, heaviness and swelling. Both types of vessel matter, but an arterial problem and a venous problem do not necessarily need the same investigation or treatment.

What do arteries and veins actually do?

Think of arteries as the outward route from the heart and veins as the return route. In the body’s main circulation, arteries deliver oxygen-rich blood to tissues and veins bring blood back after oxygen has been used. The circulation through the lungs is the important exception: pulmonary arteries carry oxygen-poor blood to the lungs, and pulmonary veins return oxygen-rich blood to the heart.

The most reliable definition is therefore the direction of travel, rather than how much oxygen the blood contains. Tiny vessels called capillaries connect the two sides and allow exchange between the blood and surrounding tissues.

Why are the vessel walls different?

Arteries have relatively thick, muscular walls suited to carrying blood under pressure from the heart. Veins operate at lower pressures and have more flexible walls. Many veins in the limbs contain valves that help direct blood towards the heart.

In the legs, returning blood upwards also depends on movement. Contracting muscles help squeeze the veins, while functioning valves limit backward flow. This is why the way symptoms change with walking, standing and rest can provide useful clues during an assessment.

What does an arterial circulation problem feel like?

When leg arteries become narrowed or blocked, the muscles may not receive enough blood for activity. One possible symptom is claudication: an aching or cramping discomfort brought on by walking, often in the calves, thighs or buttocks. It typically eases after stopping to rest.

A recurring pattern matters more than a single episode of cramp. Tell your doctor whether symptoms start after a similar walking distance and whether that distance is becoming shorter. These details can help guide an assessment for peripheral arterial disease.

Leg pain is not always vascular. Joint, muscle and nerve conditions can also affect walking. A description of symptoms helps, but examination and appropriate testing are needed before deciding what is responsible.

How can vein problems cause a different pattern?

In venous reflux, valves do not close effectively and some blood flows backwards. Varicose veins can develop, and the legs may feel heavy, achy or swollen. Symptoms often build after prolonged standing or towards the end of the day. Resting with the legs elevated may help.

These are useful patterns rather than rules that prove a diagnosis. Cramps can occur with both arterial and venous conditions, and a person can have more than one problem at the same time. Learn more about varicose veins and venous disease.

Why does the distinction change treatment?

An arterial assessment asks whether enough blood is reaching the tissues. A venous assessment asks how effectively blood is returning and whether reflux or obstruction is present. A treatment intended for one problem may not address the other.

A vascular consultation may include checking pulses, examining the skin and assessing swelling. Depending on the findings, pressure measurements or an ultrasound may be appropriate. You can read about the broader role of vascular surgery and vascular assessment before your visit.

Which symptoms need urgent assessment?

Seek immediate emergency assessment for a suddenly painful, cold, pale, numb or weak foot. New unexplained swelling in one leg, particularly with pain, warmth or redness, also needs prompt assessment because a blood clot is one possible cause. Chest pain, sudden breathlessness or collapse requires emergency help; call 995 in Singapore.

Where can I have circulation symptoms assessed in Singapore?

For persistent walking pain, leg heaviness or recurring swelling, arrange a consultation with Dr Andrew Choong at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Note what brings symptoms on, how long they last and what relieves them. This information helps the consultation focus on the right next steps.

Aortic Aneurysm Screening: Why Men Over 55 Should Know This

An aortic aneurysm can develop quietly, without an obvious warning. Finding it before an emergency creates an opportunity to measure it, arrange appropriate surveillance and discuss treatment when the balance of risks justifies repair. For men with a smoking history, high blood pressure or a family history of aneurysms, understanding personal risk is a useful starting point.

What is an aortic aneurysm?

The aorta is the main artery carrying blood away from the heart. An aneurysm is an abnormal enlargement of part of this artery as its wall stretches and weakens. It can occur in the chest or the abdomen. An abdominal aortic aneurysm, often shortened to AAA, affects the section in the tummy.

These distinctions matter because the investigation and follow-up depend on the part of the aorta involved. An abdominal ultrasound is commonly used to look for an AAA, but it is not a complete screening test for every condition affecting the chest aorta. Read more about aortic disease and its assessment.

Why can an aneurysm be present without symptoms?

Many aneurysms do not cause pain or a noticeable change in day-to-day health. They may be discovered during an ultrasound or CT scan performed for another reason. Feeling well therefore does not reliably exclude an aneurysm, and waiting for symptoms is not a screening strategy.

The important distinction is between screening someone who feels well and investigating symptoms. New abdominal or back pain requires a clinical assessment appropriate to its severity; it should not simply be booked as a routine screening appointment.

Should every man over 55 have an ultrasound?

No single age threshold applies to everyone. The video’s invitation to men over 55 is a prompt to discuss individual risk, particularly where smoking or family history is relevant. It should not be read as a universal recommendation to screen every man at 55.

Population screening recommendations commonly focus on older men, particularly those with a smoking history. These recommendations help guide a discussion; they do not replace an assessment of your family history, other risk factors and previous scan findings.

In Singapore, a discussion with your doctor can establish whether an ultrasound is appropriate for your circumstances. Bring details of any close relative with an aneurysm, previous imaging and your smoking and blood-pressure history. A family history may justify a discussion earlier than a population screening age.

What happens if an aneurysm is found?

The next step is a plan based on its location, size, growth and any symptoms, alongside your overall health. A small aneurysm may be monitored with repeat imaging. Surveillance means scheduled reassessment, rather than ignoring the finding.

Blood-pressure management and stopping smoking are important parts of care. Your clinician can explain when the next scan is due and which symptoms require urgent attention. Keep a record of the measurements and follow-up arrangements so that changes can be interpreted over time.

Does treatment always mean open surgery?

No. Some aneurysms can be repaired from inside the arteries using a stent graft, an approach known as endovascular repair. Others are better suited to open surgery. Suitability depends on the aneurysm’s anatomy and the person’s health; an operation is not automatically needed just because an aneurysm is discovered.

Early detection does not remove all risk or guarantee a particular treatment. It gives the clinical team more information and time to consider the options. Our aortic awareness information explains why recognition and follow-up matter.

When is urgent help needed?

Sudden severe abdominal or back pain, collapse, loss of consciousness or severe breathing difficulty can signal a life-threatening emergency. Call 995 in Singapore for emergency assistance. Do not wait for a clinic appointment or drive yourself if you are seriously unwell.

Where can I discuss aneurysm screening in Singapore?

For a non-emergency discussion about risk assessment or an existing aneurysm, contact Dr Andrew Choong’s clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Bring previous scan reports and a medication list so that the consultation can focus on a suitable assessment and follow-up plan.

This article provides general education and does not replace an individual medical assessment.

Varicose Veins Are Not Just Cosmetic

Varicose veins are not always just a cosmetic concern. Bulging veins can be a sign that the one-way valves in the leg veins are not working effectively. For some people, this is associated with aching, heaviness or swelling; others notice changes to the skin around the ankle.

In this video, I explain how the leg veins return blood to the heart, what happens when their valves fail and why an ultrasound assessment can be useful. The starting point is understanding your symptoms: not all varicose veins need treatment.

How do the veins in your legs work?

Arteries carry blood away from the heart, while veins return it. In the legs, returning blood has to move upwards against gravity. When you walk, your calf muscles squeeze the veins and help push blood towards the heart. A series of one-way valves helps prevent it from flowing backwards.

This differs from the arterial problem described in my previous video about leg pain when walking and claudication. Both affect circulation, but the underlying problem and the assessment are different.

What is venous reflux?

Venous reflux means that blood flows backwards through veins whose valves are not closing properly. This can increase pressure in the veins, particularly when you are standing. Superficial veins may become enlarged and twisted, producing the visible bulges we call varicose veins.

The appearance alone does not tell us how much reflux is present or whether treatment would help. I consider the symptoms, skin changes and ultrasound findings together when assessing varicose veins and venous disease.

Which symptoms deserve a closer look?

Symptoms and changes associated with venous disease can include:

• Heaviness or aching: legs that feel uncomfortable, especially after prolonged standing.

• Swelling: often noticeable around the ankle or lower leg.

• Bulging veins: enlarged veins visible beneath the skin.

• Skin changes: brownish discolouration, itching or eczema around the lower leg.

• Ulceration: a break in the skin that may be slow to heal in more advanced disease.

These findings are reasons to seek an assessment, rather than assume the problem is only cosmetic. They can also have other causes, so symptoms or photographs alone cannot confirm venous reflux.

What does a duplex ultrasound show?

A venous duplex ultrasound is a non-invasive scan that uses sound waves to examine the veins and the direction of blood flow. It can identify reflux and help map which veins are affected. This information supports the diagnosis and, where appropriate, treatment planning.

During the consultation, I would also ask when your symptoms started, what makes them worse and whether you have had previous vein treatment or blood clots. The examination and scan findings help determine the next step.

Do all varicose veins require treatment?

No. Mild or symptom-free varicose veins may need advice and observation. If symptoms affect daily life, or there are skin changes or ulcers, treatment options can be discussed in more detail.

Depending on the findings, management may include suitable activity, leg elevation, appropriately prescribed compression or a procedure to treat refluxing veins. Compression can help selected symptoms, but it does not repair faulty valves and should be chosen with your circulation and other health conditions in mind. Treatment is individual; a visible vein does not automatically mean an operation is necessary.

When is leg swelling more urgent?

Longstanding venous symptoms are different from new swelling in one leg, particularly with pain, warmth or tenderness. This needs urgent medical assessment for possible deep vein thrombosis (DVT). Do not assume a sudden change is simply your usual varicose veins.

Sudden breathlessness, chest pain or fainting requires emergency care. In Singapore, call 995 for a life-threatening emergency rather than waiting for a clinic appointment.

Varicose vein assessment in Singapore

If aching, swelling or skin changes sound familiar, contact Andrew Choong Vascular Surgery to discuss an assessment at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

This article provides general education and does not replace an individual medical assessment.

Leg Pain When Walking? It Could Be Claudication | Dr Andrew Choong

Leg pain when walking is not always caused by arthritis or simply getting older. A cramping, aching or tight feeling in the calf, thigh or buttock that repeatedly appears during walking and improves with rest can be a sign of intermittent claudication, a symptom of reduced blood flow to the leg muscles.

In the video above, I explain three simple questions that can help you describe this pattern. They cannot diagnose the cause of your pain, but they can help you recognise when a vascular assessment may be useful.

Three questions to ask about leg pain when walking

1. Does it begin after a fairly predictable walking distance? You may notice discomfort after a similar stretch of pavement or on the same hill.

2. Does it ease when you stop walking? Claudication commonly improves after a few minutes of rest.

3. Does it return when you start walking again? The same discomfort may recur as your leg muscles work harder.

If this sounds familiar, arrange a medical assessment. The pattern can suggest claudication, but joint, muscle and nerve problems can also cause leg pain. An examination helps distinguish between them.

Why can poor circulation cause this pain?

Walking increases the amount of oxygen your leg muscles need. If arteries supplying the legs are narrowed, blood flow may not increase enough to meet that demand. Stopping reduces the muscles’ oxygen needs, allowing the discomfort to settle.

This narrowing is often caused by atherosclerosis, a build-up of fatty plaque inside artery walls. When it affects the arteries supplying the limbs, it is called peripheral arterial disease (PAD). Not everyone with PAD has the classic walking-and-rest pattern.

Why does claudication matter for heart health?

When claudication is caused by PAD, the assessment also considers your wider cardiovascular health. PAD and coronary artery disease often share the same underlying process, and people with PAD have a higher risk of heart attack and stroke.

Smoking, diabetes, high blood pressure and high cholesterol are relevant risk factors. Reviewing them is part of caring for your circulation, even if your main concern is walking discomfort.

How is claudication assessed?

I would start by asking where the pain occurs, what brings it on, how quickly it settles and whether your walking distance has changed. Your medical history, medicines and risk factors also help guide the assessment.

An examination includes checking your feet, skin and leg pulses. An ankle–brachial pressure index (ABPI), also called ABI, compares blood pressure at the ankles and arms. A duplex ultrasound may be appropriate to assess blood flow and locate narrowing. Further tests depend on the findings; not everyone needs a scan.

Does claudication always need an operation?

No. Treatment often begins with managing cardiovascular risk, stopping smoking where relevant, prescribed medicines and a structured exercise programme suitable for the individual. Medicines may address cholesterol, blood pressure or blood-clotting risk.

For stable claudication, supervised or clinician-supported walking programmes can improve walking ability. The programme should follow assessment and account for other health conditions. New severe pain, pain at rest or a cold, numb foot should not be treated by simply pushing through a walk.

Angioplasty or surgery may be considered when symptoms remain significantly limiting despite treatment, or when circulation is severely compromised.

When should you seek urgent help?

Seek prompt medical assessment for new pain at rest, a foot or leg wound that is not healing, or symptoms that are worsening, particularly if you have diabetes.

A suddenly painful, cold, pale, numb or weak leg or foot needs emergency assessment. Seek emergency care immediately rather than waiting for a clinic appointment.

Assessment and Treatment Guides

Read more about vascular duplex ultrasound and leg angioplasty and stenting, including when a procedure may be considered. Not everyone with walking pain needs a scan or an operation.

Vascular assessment in Singapore

If recurring walking pain is limiting your daily activities, contact Andrew Choong Vascular Surgery to discuss an assessment at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

This video follows my introduction to September’s vascular disease awareness series. Recognising a symptom pattern is a useful first step; a clinical assessment establishes what it means for you.

This article provides general education and does not replace an individual medical consultation.

September is Vascular Disease Awareness Month | Signs & Symptoms

Leg pain when walking, persistent leg swelling and wounds that heal poorly can be warning signs of vascular disease. Some blood vessel conditions cause few or no symptoms until they become serious. Recognising a change in your circulation - and knowing when to seek help - is the message behind this video.

September’s vascular disease and peripheral arterial disease awareness campaigns are an opportunity to talk about arteries, veins, blood clots and the aorta. In the video above, I introduce a series of short explanations about vascular health, the symptoms people sometimes overlook, and when a proper assessment may be needed.

What is vascular disease?

Vascular disease affects the blood vessels that carry blood around the body. Arteries carry blood away from the heart; veins return it. The aorta is the body’s main artery.

Vascular conditions include peripheral arterial disease (PAD), varicose veins, deep vein thrombosis (DVT), aortic aneurysms and aortic dissection. These are different conditions, so their symptoms, risks and treatments are not interchangeable.

Heart health and arterial health are closely connected. PAD and coronary artery disease share risk factors such as smoking, diabetes, high blood pressure and high cholesterol. Looking after these risk factors matters beyond the heart itself.

Which symptoms should you look out for?

The topics introduced in this Short cover several changes worth paying attention to:

• Leg pain when walking. Aching or cramping brought on by walking and relieved by rest can be a sign of peripheral arterial disease, where narrowed or blocked arteries reduce blood flow to the legs. Repeated symptoms should not automatically be put down to age or fitness.

• Swelling, aching or heavy legs. These may occur with varicose veins or other venous problems. Persistent swelling, skin changes or ulcers deserve assessment; visible veins alone do not establish how serious a problem is.

• Foot or leg wounds that are slow to heal. Poor healing can have several causes, including impaired circulation. A foot wound in someone with diabetes needs prompt medical attention.

• New swelling in one leg. Especially when accompanied by pain, tenderness or warmth, this needs urgent medical assessment for a possible deep vein thrombosis. DVT is a clot in a deep vein, and not everyone develops all the typical symptoms.

These signs are reasons to seek advice, rather than a way to diagnose yourself. Muscle, joint and other medical problems can also cause leg symptoms.

Can vascular disease be silent?

Yes. Some vascular conditions develop without obvious warning signs. For example, an abdominal aortic aneurysm often causes no symptoms. An aneurysm is an abnormal widening of an artery; an aortic dissection involves a tear in the inner lining of the aorta.

This does not mean everyone needs a scan. Whether an examination, circulation test or imaging is appropriate depends on your symptoms, medical history and individual risk.

When should you seek urgent help?

Seek emergency care now for sudden severe abdominal or back pain, sudden breathlessness or chest pain, fainting, or a limb that suddenly becomes cold, painful or numb. These symptoms can signal serious problems and should not wait for a routine clinic appointment.

In Singapore, call 995 for a life-threatening emergency.

When is a vascular assessment appropriate?

Arrange a medical assessment for persistent or recurring leg pain when walking, unexplained swelling, skin changes or a wound that is not healing. Mention any diabetes, smoking history, high blood pressure or high cholesterol.

An assessment helps determine whether your symptoms relate to the arteries, veins or another cause, and whether further tests are needed. New one-sided swelling or rapidly worsening symptoms require more urgent attention.

Follow the September vascular health series

In this introductory video, I set out the topics for the month: walking-related leg pain, poor circulation, diabetic foot wounds, varicose veins, blood clots, aortic aneurysms and aortic dissections.

September also includes Aortic Dissection Awareness Day on 19 September and World Heart Day on 29 September. The next Short starts with a commonly missed warning sign of PAD: leg pain when walking.

Vascular care in Singapore

For non-emergency concerns about your circulation, contact Andrew Choong Vascular Surgery to enquire about an assessment with Dr Andrew Choong, Consultant Vascular and Endovascular Surgeon.

The clinic is at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

This article expands on the accompanying video for general education. It does not replace an individual medical assessment or personal medical advice.

What Is a Pulmonary Embolism? | Blood Clot Awareness Month | Video 4

A pulmonary embolism, or PE, happens when a blood clot blocks an artery in the lungs. It often begins as a clot in a deep vein in the leg or pelvis, called deep vein thrombosis, or DVT. Part of that clot can break away, travel through the right side of the heart and lodge in the pulmonary arteries.

In this fourth video of my Blood Clot Awareness Month series, I explain why recognising PE matters. It can be life-threatening, and the right response to possible symptoms is prompt medical assessment.

Why can a clot in the lungs be dangerous?

The pulmonary arteries carry blood from the heart to the lungs, where it picks up oxygen. A clot can obstruct that circulation, interfere with oxygen transfer and put strain on the right side of the heart.

The effect varies. Some people remain relatively stable, while others develop low oxygen levels, low blood pressure or collapse. The severity depends on the effect on the circulation and heart, alongside the person's overall health. A description of symptoms alone cannot establish how serious a PE is.

What symptoms need emergency attention?

Possible symptoms of pulmonary embolism include:

• Sudden or unexplained breathlessness.

• Chest pain, which may be worse when breathing in.

• Coughing up blood.

• A rapid heartbeat, marked light-headedness or fainting.

These symptoms may have other causes, but suspected PE needs emergency assessment. If you have symptoms suggesting PE, call 995 in Singapore. Do not wait for a routine clinic appointment or for symptoms to become severe.

Some people also have a painful, swollen or warm leg from an underlying DVT; others have no obvious leg symptoms. The absence of leg swelling does not rule out a pulmonary embolism.

How are DVT and pulmonary embolism connected?

DVT and PE are two forms of venous thromboembolism, often shortened to VTE. A deep-vein clot may stay in place, extend, or release material that travels to the lungs.

Risk can increase after surgery, during prolonged immobility, with active cancer, in pregnancy or after childbirth, and with certain hormone medicines. A previous blood clot also matters. Sometimes no clear trigger is identified. Knowing the circumstances helps guide treatment and decisions about preventing another clot.

I explain the leg-vein condition in more detail on my deep vein thrombosis page.

For treatment of related leg-vein clots, read the DVT treatment guide.

How is pulmonary embolism diagnosed?

Assessment combines the symptoms, risk factors, examination and appropriate investigations. Depending on the clinical situation, these may include blood tests and imaging. CT pulmonary angiography is commonly used to look for clots in the pulmonary arteries; alternative imaging may be chosen when it is more appropriate.

Tests may also assess the effect on the heart and oxygen levels. This information helps the treating team decide the urgency, location and type of care needed. Not everyone requires the same tests or treatment pathway.

Does every pulmonary embolism need clot removal?

No. Anticoagulant medicines are the main treatment for many people with PE. Often called blood thinners, they reduce further clotting while the body's own processes gradually deal with the clot. They do not physically extract it.

In the video, I describe aspiration thrombectomy: a catheter-based procedure that can remove clot from the pulmonary arteries. This is an option for selected patients, particularly when PE is causing serious circulatory problems or when the balance of risks favours an intervention.

Other advanced treatments include clot-dissolving medication or surgical removal in particular circumstances. These approaches carry risks and require specialist assessment. A procedure is not automatically better than anticoagulation, and recovery time cannot be promised in advance.

What happens after the immediate treatment?

Follow-up matters. The team reviews medication, bleeding risk, the likely cause of the clot and how long treatment should continue. Persistent breathlessness or reduced exercise tolerance after PE should be discussed rather than assumed to be part of normal recovery.

The pulmonary embolism guide brings together warning signs, treatment and follow-up after a lung blood clot.

For a non-emergency discussion about DVT, clot risk or vascular follow-up in Singapore, you can contact my clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. New symptoms suggesting PE require emergency assessment first.

This article provides general education and does not replace an individual medical assessment.

What Is a DVT? Deep Vein Thrombosis Explained

Deep vein thrombosis, or DVT, is a blood clot in a deep vein. It most often affects the leg or pelvis, although it can also develop in an arm. Deep veins carry blood back towards the heart, so a clot can obstruct that return flow.

In the third instalment of my Blood Clot Awareness Month series, I explain why DVT deserves attention: it can cause immediate symptoms, sometimes lead to a pulmonary embolism, and leave longer-term problems in the affected leg. Recognising a possible clot is the first step towards getting it assessed.

What does a DVT feel or look like?

Possible signs include new swelling, pain or tenderness, warmth, and a change in skin colour, usually affecting one leg. The discomfort may involve the calf or thigh. An arm DVT can produce similar symptoms in the arm.

These signs do not prove that a clot is present. Muscle injuries, infections and other conditions can look similar, and some DVTs cause few or no obvious symptoms. Comparing one leg with the other can reveal a change, but a home examination cannot confirm or exclude DVT.

New, unexplained one-sided swelling or pain warrants urgent medical assessment. Do not wait for symptoms to become severe before seeking advice.

Why can a leg clot affect the lungs?

Part of a DVT can break off and travel through the bloodstream to the pulmonary arteries in the lungs. This is called a pulmonary embolism, or PE. It can interfere with oxygen exchange and strain the heart.

Sudden breathlessness, chest pain, coughing up blood or fainting need emergency assessment. For these possible pulmonary embolism symptoms, call 995 in Singapore; do not wait for symptoms to worsen. A routine vascular appointment is not the appropriate first step when PE is suspected.

DVT and PE are related conditions collectively called venous thromboembolism, or VTE. Not every DVT causes PE, but the possibility is one reason early diagnosis and treatment matter.

Can DVT threaten the leg itself?

Rarely, a very extensive DVT can severely obstruct the veins draining the leg. The leg may become dramatically swollen, very painful and discoloured. This severe condition, known as phlegmasia, can threaten the limb and requires emergency specialist care.

This is different from the more usual presentation of DVT, but it illustrates why a rapidly worsening, painful swollen leg should not be managed by waiting at home. Emergency assessment is particularly important if the limb becomes blue, cold or numb.

What is post-thrombotic syndrome?

After a DVT, residual obstruction or damage to the vein valves can make it harder for blood to return efficiently. Some people develop post-thrombotic syndrome, with persistent swelling, aching, heaviness or skin changes. In more severe cases, a venous ulcer can develop.

These problems can affect daily life even after the immediate clot has been treated. They do not happen to everyone. Follow-up allows ongoing symptoms to be assessed and a suitable management plan to be discussed.

Who is more likely to develop DVT?

Risk factors include recent surgery or hospitalisation, reduced mobility, a previous clot, active cancer, pregnancy and the period after childbirth. Certain hormone medicines and inherited clotting tendencies can also increase risk.

Long journeys can contribute through prolonged sitting, particularly when other risk factors are present. Sometimes a DVT develops without an obvious trigger. The clinical history helps determine both the likely cause and how best to reduce future risk.

How is DVT assessed and treated?

A clinician considers the symptoms, examination and risk factors. An ultrasound scan is commonly used to look for a clot in the deep veins; blood tests may form part of the assessment in selected circumstances.

Anticoagulant medicines are the main treatment for most DVTs. They help prevent the clot growing and reduce the chance of further clots while the body's natural processes work on the existing clot. Treatment duration depends on the individual situation.

Selected patients with extensive, severely symptomatic clots may be considered for catheter-based treatment. This is not necessary for every DVT. Decisions balance potential benefit against bleeding and procedural risks.

For more detail, read the guides to DVT treatment, venous duplex ultrasound and pulmonary embolism.

You can read more about DVT assessment and treatment or contact my Singapore clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563 for non-emergency advice and follow-up.

This article provides general education and does not replace an individual medical assessment.

Why Do Blood Clots Form? DVT & PE Risk Explained

Why does a blood clot develop inside a vein when there has been no visible cut or injury? In this second video of my Blood Clot Awareness Month series, I explain three processes that help answer that question: slow blood flow, a greater tendency to clot, and injury to the vessel lining.

Together, these are known as Virchow's triad. One or more can contribute to deep vein thrombosis, or DVT. Understanding them helps explain why clot risk often changes around an operation, illness, pregnancy or a period of reduced mobility.

What happens when blood flow slows?

Movement helps blood return from the legs towards the heart. When the calf muscles contract, they support that return flow through the veins. Long periods without normal movement can allow blood to pool and increase the opportunity for a clot to form.

This can happen during bed rest, recovery from major surgery or a long journey. The level of risk varies: a person with a previous DVT, active cancer or several other risk factors may need a different prevention plan from someone without those factors.

Prolonged sitting is therefore part of the explanation, rather than a complete explanation on its own. An otherwise ordinary journey may become more relevant when it follows an operation or takes place during a period of illness.

When is blood more likely to clot?

Some conditions shift the body's clotting balance towards clot formation. Active cancer, pregnancy and the period after childbirth are examples. Certain hormone medicines and inherited clotting disorders can also contribute.

Previous DVT or pulmonary embolism is particularly relevant to a risk assessment. Family history can provide useful context, although it does not automatically mean someone has an inherited disorder or needs a blood test for one.

If you take a prescribed medicine that may affect clot risk, discuss it with your clinician. Stopping treatment without advice can create other problems; prevention decisions need to account for both the reason for the medicine and your individual circumstances.

How does injury to a vessel lining contribute?

The inside surface of a blood vessel normally helps blood flow smoothly. Surgery, trauma and inflammation can disturb that lining and activate the clotting response.

After an operation, several parts of the triad can overlap: there may be tissue or vessel injury, less movement than usual and a temporary change in clotting activity. That is why clot prevention is considered as part of surgical care, with measures chosen for the procedure and the patient.

A clot can also develop without a clearly identifiable trigger. The absence of recent travel or surgery does not rule out DVT.

What can help reduce the risk?

Prevention should match the situation. Useful discussions include when it is safe to mobilise after surgery, how to avoid prolonged immobility during travel, and whether a particular illness or previous clot calls for additional measures.

For some people, clinicians recommend anticoagulant medication or suitable compression as part of a prevention plan. These are not measures that everyone should start independently. Bleeding risk and other medical conditions affect what is appropriate.

Keeping normally hydrated is sensible general care, but drinking water is not a proven substitute for movement or an individual clot-prevention plan. If you have a previous clot or several risk factors, seek advice before a long journey or planned operation.

Which symptoms should not be ignored?

DVT may cause new swelling, pain, warmth or a colour change in one leg. These symptoms need urgent assessment because an examination alone cannot reliably establish the cause.

A clot can travel from a deep vein to the lungs and cause pulmonary embolism. Sudden breathlessness, chest pain, coughing up blood or fainting require emergency assessment. For these possible pulmonary embolism symptoms, call 995 in Singapore; do not wait for a routine appointment.

You can read more about deep vein thrombosis and its assessment. For a planned discussion of vascular symptoms or clot risk, contact my Singapore clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

This article provides general education and does not replace an individual medical assessment.

What is a Blood Clot? | Singapore Vascular Surgeon

A blood clot is a mass formed when blood changes from a flowing liquid into a more solid structure. Clotting is normally protective: after an injury, it helps stop bleeding. The problem arises when a clot forms inside a blood vessel where it is not needed and obstructs the circulation.

In the first video of my Blood Clot Awareness Month series, I introduce this distinction. A clot is not simply “good” or “bad” in isolation. Its location, cause and effect on blood flow determine what it means for your health.

How does normal clotting protect us?

When a blood vessel is injured, platelets gather at the damaged area and help form a plug. Clotting proteins create a mesh of fibrin that supports it. Together, these processes help seal the injury while healing takes place.

The body also has mechanisms that limit clotting and break down clots when they are no longer needed. Health depends on keeping that balance: too little clotting can cause bleeding, while inappropriate clotting can block a vessel.

What is the difference between a clot in a vein and an artery?

Arteries carry blood away from the heart to supply the body. Veins return blood towards the heart. A clot can develop in either system, but the consequences and treatments differ.

A vein clot can obstruct blood returning from a limb and may travel to the lungs. An artery clot can interrupt the oxygen-rich blood reaching an organ or limb. The word “clot” therefore covers several conditions; it does not identify one diagnosis or one treatment.

My overview of vascular surgery explains how arterial and venous conditions fit within vascular care.

What are DVT, PE and VTE?

Deep vein thrombosis (DVT) is a clot in a deep vein, most often in the leg or pelvis. It may cause new one-sided swelling, pain, warmth or a change in skin colour, although some people have few obvious symptoms.

Pulmonary embolism (PE) occurs when a clot, commonly from a DVT, travels to and blocks an artery in the lungs. It can affect breathing and place strain on the heart.

Venous thromboembolism (VTE) is the collective term for DVT and PE. Understanding these terms helps make sense of medical discussions, but symptoms still need an assessment rather than a diagnosis based on an online description.

What is acute limb ischaemia?

A sudden blockage of an artery supplying a limb can cause acute limb ischaemia. This means the tissues are not receiving enough blood and oxygen. It is a vascular emergency.

A suddenly painful, cold, pale or numb foot or leg, particularly with weakness, requires immediate emergency assessment. Do not wait to see whether walking, massage or rest resolves it. It is different from the recurring walking discomfort described in peripheral arterial disease, although both involve the arterial circulation.

When should I seek help for a possible clot?

New, unexplained swelling or pain in one leg warrants urgent medical assessment for possible DVT and other causes. Sudden breathlessness, chest pain, coughing up blood or fainting could indicate PE and require emergency assessment.

For possible pulmonary embolism symptoms or a suddenly cold, painful, numb or weak limb, call 995 in Singapore. Early assessment allows the treating team to identify the problem and start appropriate care.

How are blood clots treated?

Treatment depends on where the clot is, how it is affecting the circulation and the person's overall health. Anticoagulants are commonly used for DVT and PE to reduce further clotting while the body works on the existing clot.

Some situations require clot-dissolving treatment, catheter-based removal or surgery. These are selected according to urgency, expected benefit and risk; they are not interchangeable treatments for every clot.

The guides to DVT treatment and pulmonary embolism explain these care pathways in more detail.

For a non-emergency discussion about DVT, previous clots or vascular symptoms, contact my clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. Dr Andrew Choong's clinic can support assessment and follow-up, while acute emergency symptoms require immediate hospital care.

This article provides general education and does not replace an individual medical assessment.

Blood Clot Removal for DVT | Modern Treatment Explained

Treatment for deep vein thrombosis, or DVT, can now include catheter-based techniques that remove clot from a vein. In this video, I explain how vascular treatment has developed, from anticoagulant medicines to clot-dissolving therapies and mechanical clot removal.

These developments add options for selected patients. They do not mean every DVT needs a procedure. The central question is whether removing the clot is likely to offer enough benefit for that person to justify the risks.

Why are anticoagulants still central to DVT treatment?

Anticoagulants, often called blood thinners, reduce the blood's ability to form further clot. They help prevent an existing DVT from growing and lower the risk of additional clots while the body's own processes gradually deal with it.

For most people with DVT, anticoagulation remains the main treatment. The medication, duration and follow-up plan depend on factors such as the clot's location, its likely cause, previous clotting events and bleeding risk.

A procedure does not automatically replace anticoagulation. Many patients still need medication afterwards, together with monitoring and advice about future clot risk.

What is catheter-based blood clot removal?

A catheter is a thin tube introduced into a blood vessel through a small access point. Guided by imaging, it can be positioned near or within a clot. The technique used depends on the clot, the anatomy and the clinical circumstances.

Catheter-directed thrombolysis delivers clot-dissolving medicine to the affected area. Mechanical thrombectomy uses a device to remove clot; aspiration thrombectomy uses suction. Sometimes approaches are combined, and a separate narrowing in the vein may need assessment.

These procedures differ from simply taking anticoagulant medication. They aim to clear clot more directly, but each approach has limitations and potential complications.

Who might benefit from a procedure for DVT?

Specialist assessment may consider an intervention for selected patients with a recent, extensive and severely symptomatic clot, particularly involving the major veins in the upper thigh and pelvis. Rarely, a DVT severely compromises drainage from the limb and becomes a limb-threatening emergency.

Important considerations include:

• Where the clot is and how long symptoms have been present.

• The severity of swelling, pain and any threat to the limb.

• Bleeding risk, other medical conditions and functional needs.

• The likely benefit of a procedure compared with medication alone.

A smaller or less symptomatic clot may be best managed without an intervention. Having access to modern technology is useful when it supports the right decision for the patient.

Can clot removal prevent long-term leg problems?

Some people develop persistent swelling, aching, skin changes or ulcers after a DVT. This is called post-thrombotic syndrome and can reflect lasting vein obstruction or damage to the valves.

Removing clot may improve symptoms in appropriately selected patients, but it cannot guarantee that the leg will return completely to normal or that post-thrombotic syndrome will be prevented. Results vary with the clot, the vein and the individual.

Follow-up remains important whether treatment involves medication alone or a procedure. Persistent symptoms deserve review and a management plan suited to their cause.

What about clot removal from the lungs?

The video also describes aspiration treatment for pulmonary embolism, where a clot blocks arteries in the lungs. Catheter-based removal is an option in selected serious cases, within an urgent specialist treatment pathway.

Many pulmonary embolisms are treated with anticoagulation. More advanced treatment is considered according to the effects on the circulation and heart, the person's condition and the risks of treatment. It is not a routine extension of every DVT procedure.

What should I discuss before treatment?

Ask what the proposed treatment aims to achieve, what medication alone is expected to do, and which risks apply to you. Depending on the procedure, risks can include bleeding, vessel injury, problems related to contrast and the need for further treatment. Recovery and follow-up requirements should also be clear.

The DVT treatment guide brings together medicine, selected clot-removal procedures, venous stenting and follow-up.

New one-sided leg swelling or pain needs urgent assessment. Sudden breathlessness, chest pain or fainting can indicate pulmonary embolism and requires emergency care. Call 995 in Singapore; do not wait for a routine appointment.

For non-emergency advice, read more about DVT treatment or contact my clinic at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. I can discuss which options fit your diagnosis and circumstances.

This article provides general education and does not replace an individual medical assessment.

World Diabetes Day 2025: Diabetes, Artery Health and Foot Care

Diabetes can affect the blood vessels long before a person notices a circulation problem. For World Diabetes Day, my video explains why looking after your arteries belongs alongside managing blood glucose. The aim is to recognise risk early, identify problems that need treatment and protect long-term health.

A circulation assessment is most useful when it answers a clear clinical question. It should be guided by symptoms, examination and individual risk, with a plan for what the findings will change.

How can diabetes damage the arteries?

Persistently high blood glucose can damage blood vessels and contribute to atherosclerosis, the build-up of plaque within artery walls. Blood pressure, cholesterol, smoking and other factors also influence risk. As arteries become narrowed, less blood may reach the tissues they supply.

The consequences depend on the location. Arterial disease can contribute to heart attacks, strokes and reduced blood flow to the legs and feet. In the legs, this is known as peripheral arterial disease, or PAD.

Diabetes does not mean that every artery is blocked. It means that vascular risk deserves active attention, even when someone feels well.

Why are the feet especially important?

Two problems can occur together: reduced circulation and nerve damage. Poor circulation can make wounds harder to heal. Nerve damage can reduce sensation, so a blister, pressure injury or small cut may go unnoticed.

This is why pain alone is an unreliable warning system. A foot can need attention even if it does not hurt. Look over both feet regularly, including the soles and between the toes, and seek help if you cannot examine them yourself. Appropriately fitting footwear and regular foot reviews are also important.

A diabetic foot ulcer is a serious complication, but it is not a prediction that an amputation is inevitable. Prompt assessment, infection treatment when needed, pressure relief and attention to circulation can all form part of a coordinated care plan.

What can an ABPI or arterial duplex ultrasound show?

An ankle–brachial pressure index, also called ABPI or ABI, compares blood pressure at the ankle with blood pressure in the arm. It helps assess whether arterial narrowing may be reducing blood flow to the legs.

Diabetes can make arteries stiff and difficult to compress. This can produce a normal-looking or high ankle pressure despite underlying disease. A normal ABPI therefore does not rule out PAD by itself in someone with diabetes.

Arterial duplex ultrasound uses sound waves to examine arteries and blood flow. Depending on the findings, other measurements, such as toe pressures, may also be helpful. These tests assess particular aspects of circulation; they do not provide a single all-clear for every artery in the body.

Does everyone with diabetes need the same vascular tests?

No. The assessment should start with the history and examination, including symptoms, foot condition, pulses and previous ulcers or vascular disease. Your clinician can then decide which tests are appropriate and whether a specialist review is needed.

Tell your care team about calf discomfort when walking, a change in walking distance, persistent foot pain, colour changes or a wound that is slow to heal. An absence of typical walking pain does not exclude a circulation problem.

When should a foot problem be checked urgently?

A new ulcer, spreading redness, discharge or a hot, swollen foot needs prompt medical assessment. Seek emergency care for a suddenly cold, pale or numb foot, severe new pain, blackened tissue or a foot infection accompanied by fever or feeling seriously unwell. Do not wait for a routine appointment if the foot is deteriorating.

What helps protect vascular health over time?

Work with your usual care team on blood glucose, blood pressure and cholesterol, take prescribed treatment consistently and seek support to stop smoking if needed. Combine these measures with foot care and physical activity suited to your condition.

For concerns about diabetes and leg circulation, contact Andrew Choong Vascular Surgery at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. An individual assessment can help clarify the next step.

World Stroke Day 2025: Carotid Artery Disease and Stroke Prevention

Some strokes can be prevented by treating disease in the carotid arteries, the major arteries in the neck that supply the brain. For World Stroke Day, my video explains this part of vascular surgery and an equally important message: recognising stroke symptoms must lead to immediate action.

If someone develops sudden facial weakness, arm weakness or difficulty speaking, call 995 in Singapore. Do not wait for a clinic appointment. The same applies if the symptoms improve or disappear.

How can carotid artery disease cause a stroke?

Fatty material, known as plaque, can build up inside a carotid artery and narrow it. A clot or debris associated with that plaque can travel towards the brain and interrupt its blood supply, causing an ischaemic stroke.

Carotid disease is one possible cause of stroke. Clots can also arise from the heart, including in people with atrial fibrillation, or develop within arteries in the brain. Other strokes are caused by bleeding. Identifying the cause matters because prevention and treatment need to address the particular problem.

Can a vascular operation prevent every stroke?

No. Carotid procedures reduce stroke risk in selected people whose artery disease is suitable for treatment. They cannot prevent strokes from every cause and are not appropriate for everyone with a narrowing.

The decision depends on the degree of narrowing, whether it has caused a recent stroke or transient ischaemic attack, the anatomy of the arteries, the person’s health and the risks of the proposed procedure. A narrowing found without symptoms requires a different discussion from one associated with a recent neurological event.

What are carotid endarterectomy and carotid stenting?

Carotid endarterectomy is an operation to remove plaque from within the affected artery. Carotid artery stenting treats the narrowing with a small mesh tube placed through a catheter. The choice between procedures depends on an individual assessment; a less invasive approach is not automatically the right option for every person.

Both procedures have potential complications, including stroke. The expected benefit must outweigh those risks. If an intervention is recommended, the treating team should explain why it is appropriate, how soon it is needed and what recovery and follow-up involve.

Compare carotid endarterectomy, stenting and medical treatment in the detailed treatment guide.

Does prevention still involve medicines and daily habits?

Yes. Care for carotid artery disease also includes managing vascular risk. Depending on the diagnosis, this may involve prescribed antiplatelet and cholesterol-lowering medicines, blood pressure and diabetes management, and support to stop smoking.

Physical activity, nutrition and taking prescribed treatment consistently remain relevant whether or not an operation is advised. Do not start, stop or change medication because of a general article; your own plan should reflect your medical history.

What does FAST mean?

• Face: a sudden droop or weakness on one side of the face.

• Arms: sudden weakness or difficulty keeping one arm raised.

• Speech: new slurring, difficulty speaking or trouble understanding speech.

• Time: call 995 immediately if any of these signs appears.

All three signs do not need to be present. Sudden loss of vision, loss of balance or other new neurological symptoms can also be important. Note when symptoms started, or when the person was last known to be well, and tell the emergency team.

What if the symptoms have already gone away?

A transient ischaemic attack, or TIA, can produce stroke-like symptoms that resolve. It is still an emergency warning, not a reason to wait and see. Urgent assessment is needed to establish the cause and reduce the risk of a subsequent stroke.

If carotid disease is identified, the specialist team may arrange ultrasound or other imaging and discuss medical treatment and whether a procedure is indicated. The role of vascular surgery is part of that wider assessment.

For planned assessment of known carotid artery disease, contact Andrew Choong Vascular Surgery at Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563. For new stroke or TIA symptoms, call 995 immediately.

World Thrombosis Day: How DVT and Pulmonary Embolism Can Be Fatal

A blood clot in a deep leg vein can become life-threatening if part of it travels to the lungs. That is the connection between deep vein thrombosis (DVT) and pulmonary embolism (PE), and it is the central message of my World Thrombosis Day video.

I am Dr Andrew Choong, a vascular surgeon in Singapore. On 13 October, World Thrombosis Day is an opportunity to explain what blood clots are, who may be at risk and which symptoms should prompt action. Recognising a possible clot early can make an important difference.

What is the difference between DVT, PE and VTE?

Deep vein thrombosis means a blood clot has formed within a deep vein, commonly in the leg. It can obstruct the return of blood towards the heart and cause swelling or discomfort. Some clots produce few obvious symptoms.

A pulmonary embolism happens when clot material travels through the circulation and blocks an artery in the lungs. The consequences range from breathlessness to a dangerous strain on the heart and sudden collapse. DVT and PE together are called venous thromboembolism, or VTE.

Thrombosis also occurs in arteries. The widely used World Thrombosis Day statistic that around one in four deaths worldwide involves a condition caused by thrombosis includes conditions such as heart attack and stroke; it does not mean that one in four people dies from a leg DVT.

Why can a blood clot develop?

Clot formation becomes more likely when blood flow slows, the vessel lining is affected or the blood has an increased tendency to clot. These factors can overlap. In my video, I highlight surgery, prolonged immobility and long journeys as situations in which people should be aware of their individual risk.

Hospital admission is especially important. Up to 60% of VTE cases are associated with a hospital stay, occurring during admission or within 90 days afterwards. That is why prevention planning may continue beyond the day a patient leaves hospital.

Your risk depends on the whole picture, including previous clots, current illness and treatment. A long flight does not affect everyone equally, and prevention should reflect your circumstances.

Which symptoms should I recognise?

A possible DVT needs prompt medical assessment, particularly when a change affects one leg. Warning signs may include:

• New swelling of the calf or whole leg.

• Pain or tenderness without a clear explanation.

• Warmth or a change in skin colour.

Sudden unexplained breathlessness, chest pain, fainting or collapse can indicate PE or another serious emergency. A racing heartbeat may accompany these symptoms. In Singapore, call 995 for an emergency ambulance when severe symptoms develop. Do not wait for a routine clinic appointment.

Symptoms alone cannot confirm or exclude a clot. Other conditions can look similar, and the absence of dramatic swelling does not make every situation safe.

How are DVT and pulmonary embolism treated?

Assessment starts with the symptoms and risk factors. Depending on the findings, clinicians use blood tests and appropriate imaging, such as ultrasound for suspected leg DVT. Testing is selected for the clinical situation.

Anticoagulant medication is central to treatment for many patients. It reduces the risk of clot extension and further clot formation while the body deals with the existing clot. The choice and duration require an individual assessment, including bleeding risk.

In selected cases, specialists may consider catheter-based treatment to remove or dissolve clot. My video describes the role of vascular surgeons in restoring blood flow, but a clot-removal procedure is not necessary or suitable for every DVT. The location, severity, timing and patient’s overall condition all matter.

What can I do after watching this video?

Know the warning signs, follow your hospital team’s prevention instructions and discuss personal clot risk before major surgery or prolonged immobility. If you develop new symptoms after discharge, mention your recent admission when seeking help.

For a non-emergency discussion about DVT and venous health, you can contact Andrew Choong Vascular Surgery. Current clinic location: Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.

Vascular Surgery in 60 Seconds: Aorta, Arteries and Veins Explained

A vascular surgeon is a specialist in the blood vessels that carry blood around the body. In my 60-second video, I describe us as circulation doctors: we assess and treat problems affecting arteries and veins, using a range of medical, minimally invasive and open surgical approaches.

I am Dr Andrew Choong, a vascular surgeon in Singapore. Understanding the scope of vascular surgery can help you recognise why symptoms as different as walking pain, swollen legs and a wound that will not heal may need a circulation assessment.

What is the difference between an artery and a vein?

Arteries carry blood away from the heart towards the tissues. Veins return blood towards the heart. They are parts of the same circulation, but the conditions affecting them - and the tests and treatments they need - can be very different.

An artery narrowed by disease may not deliver enough blood to a muscle or wound. A vein with faulty valves may allow blood to pool in the leg. A blood clot can cause another kind of obstruction. The first job is to identify which problem is present.

Which conditions does a vascular surgeon treat?

Vascular surgery covers a broad range of circulation problems. The examples in my video include:

• Aortic disease: aneurysms and dissections affecting the body’s main artery.

• Leg artery disease: narrowed or blocked arteries that may cause walking pain, rest pain or poor wound healing.

• Venous disease: varicose veins and deep vein thrombosis.

• Carotid artery disease: selected artery problems in the neck relevant to stroke prevention.

• Dialysis access: creating and maintaining suitable access to the circulation for haemodialysis.

Wound care and limb preservation are also important parts of vascular practice. When poor blood flow contributes to a foot or leg wound, addressing the circulation may be one part of a wider treatment plan.

Is vascular surgery the same as cardiology?

The specialties are related, but their focus differs. Cardiologists primarily assess and treat the heart. Vascular surgeons mainly manage blood vessels outside the heart and brain, including the arteries in the neck and vessels throughout the body.

Some techniques overlap. Balloons, wires and stents can be used in both heart and peripheral vascular procedures. The presence of a stent does not, by itself, tell you which specialty or condition is involved.

Complex aortic and other vascular conditions may also involve several specialties working together. The appropriate team depends on the part of the circulation affected and the treatment required.

Does seeing a vascular surgeon mean I need an operation?

No. An assessment may lead to advice, medication, monitoring or further tests. For example, management of peripheral arterial disease can include cardiovascular risk reduction and structured exercise, with a procedure considered when clinically indicated.

For some patients, endovascular treatment offers a way to work inside a blood vessel through a small access site. Depending on the problem, this may involve a balloon, stent or another device. Other patients are better served by open surgery, such as a bypass or repair.

The decision starts with the diagnosis, symptoms, scan findings and goals of treatment. A procedure should have a clear purpose that the patient understands.

When should I seek a circulation assessment?

Persistent leg pain when walking, troublesome varicose veins, unexplained swelling or a wound that is not healing deserve medical attention. These symptoms have several possible causes, so an examination is more useful than assuming that every leg problem is vascular.

Some changes are emergencies. A suddenly cold, pale, painful or weak limb, sudden severe chest or back pain, or sudden breathlessness with collapse needs immediate emergency assessment. In Singapore, call 995 for severe emergency symptoms.

Where can I discuss vascular symptoms in Singapore?

You can contact Andrew Choong Vascular Surgery for a non-emergency consultation to discuss your symptoms, relevant scans and treatment options. My aim is to explain the circulation problem and the reasons for any proposed next step.

Current clinic location: Mount Elizabeth Novena Specialist Centre, #09-22, 38 Irrawaddy Road, Singapore 329563.