Surgical Dermatology

Our dermatologists are experts in cutaneous surgery. We routinely perform skin surgeries on all parts of the body including the face. Common procedures we do include skin biopsies, removal of cysts, mole removal, excision of skin cancers and nail surgeries. Dr Koh Hong Yi is an experienced dermatologic surgeon and Mohs micrographic surgeon. He was trained at the renowned Ninewells Hospital in the UK, and has performed numerous skin surgeries, mostly on the head and neck.

Our specialists will perform a detailed assessment of your condition and discuss with you the various treatment options available. These may include conservative management (no treatment), medical therapy, or surgery. Different surgical options where available will be offered to you, and our doctors will recommend what they feel is the best option that meets your requirements.

Financial counseling will be done so that you will know the cost of any procedure before you decide. Our clinic adheres to the latest surgical fee benchmarks set by the Ministry of Health.

Most surgeries can be performed in the fully equipped operating room within our clinic. Insurance companies often recognize this as a Day surgery for claims purposes. We will provide the required medical documents to facilitate your insurance claims. Our clinic is Medisave-accredited and we are able to perform E-filing for surgeries done in our clinic.

If you prefer to have your procedure performed in the operating theatre in the hospital (eg. Gleneagles Hospital), under sedation or general anaesthesia, these can also be arranged.

Your well-being and safety are our priority. Our specialist will personally perform and oversee your surgery from beginning to the end. Most of our skin surgeries are performed under local or topical anaesthesia, and are considered day surgeries. Over-night stays are not required.

After the procedure, you will be given instructions on how to take care of the wound, and ways to contact us if you encounter any problems at home. An appointment to follow-up with the doctor will be arranged.

Cryotherapy is a form of minimally invasive treatment that freezes tissue on the skin surface using an extremely cold liquid or instrument (cryogen). This causes the tissue to be damaged and fall off the skin. Cryotherapy can be used to treat a wide range of skin conditions. Our clinic uses liquid nitrogen, which is -196 degrees Celsius. Liquid nitrogen is colder than other cryogens one can get off the shelf and is the most effective cryogen for medical uses.

Cryotherapy can be administered using a spray canister or a cotton bud. Liquid nitrogen is sprayed or applied onto the skin lesion being treated. The lesion will turn white and hard as it becomes frozen. The doctor will control the time and degree of application to achieve the desired "freeze-damage". The lesion is then allowed to thaw. The doctor may repeat the treatment depending on the size and type of lesion.

The patient may observe some of the damaged tissue falling off a few days later. For deep and bigger lesions, cryotherapy will need to be repeated, sometimes every one to two weeks.

Cryotherapy can be used to treat a wide variety of conditions including benign (non-cancerous) and malignant (cancerous) growths on the skin. Common lesions treatable by cryotherapy include:

1. Viral warts
2. Molluscum contagiosum
3. Skin tags
4. Seborrhoeic keratoses (also known as age or liver spots)
5. Actinic keratoses (a form of pre-cancerous growth)
6. Keloid scars
7. Some types of skin cancers

Cryotherapy can be safely performed in most people, including elder folks and pregnant women. It is a quick office procedure that does not require much preparation or any anaesthesia.

There is often a transient, stinging sensation when cryotherapy is performed, which young children may not tolerate. Complications and risks are usually minimal, but can include:

1. Pain (transient)
2. Redness and swelling (transient)
3. Blistering and break in the skin
4. Changes in skin pigmentation

Cryotherapy should be performed by a trained provider, who can counsel you about these potential side effects and how to minimize them.

Cysts are common, benign (non-cancerous) growths that can occur anywhere on the body. Cysts usually appear as round, dome-shaped lumps that lie beneath the skin. They can feel firm or fluctuant, and sometimes have a pore on the overlying skin. If a cyst is squeezed, whitish malodourous material may discharge from the pore.

There are several types of cysts. The commonest is the epidermal (sebaceous) cyst which can occur anywhere on the body. Trichilemmal cysts are usually found on the scalp. Acne cysts are not "true" cysts but pseudocysts, and usually found on the face.

Cysts can be of various sizes and will usually stop growing after a while. Patients should avoid squeezing a cyst, as it may leave to cyst rupture, inflammation, pain and swelling. A cyst drained by squeezing often forms back again. Cysts on the back and the thighs are prone to rupture and inflammation when one lies or sits down, and hence should be removed.

Many cysts can be left alone, and no particular treatment is required. Treatment is recommended if a cyst causes pain and swelling due to inflammation or infection, if it is located on the back or legs and hence prone to rupture, for aesthetic reasons, or to confirm the diagnosis. Simple incision and draining the cyst is usually inadequate, and the cyst is likely to recur. Complete surgical excision, removing the whole sac of the cyst, ensures the cyst is unlikely to recur.

Cyst removal can be done in our clinic, under local anaesthesia, like a day surgery. A small incision is made over the cyst, the skin is stretched apart, and the cyst underneath is located and removed completely with its whole lining sac. For average sized and uninflamed cysts, a mini-incision can be made and then closed with only a few stitches. This reduces the size of the scar.

Electrosurgery uses a machine that converts alternating electrical current to heat energy. The heat generated is used to cauterize (burn off) skin growths, and to stop bleeding during surgery. Electrosurgery is commonly used to remove small skin blemishes on the skin surface.

The heat energy from an electrosurgery device is usually delivered using a fine probe. The probe may be held just above the surface of the skin or touch the skin gently. This cauterizes (burns off) the skin lesion being treated. Electrosurgery is usually performed under topical anaesthesia (using numbing cream) or local anaesthesia (injection). Most patients will feel no pain or just a slight pricking sensation.

Electrosurgery is used to treat a wide range of bumps on the skin, including:

1. Seborrhoeic keratoses (age or liver spots)
2. Viral warts
3. Skin tags
4. Some types of superficial skin cancers

Electrosurgery offers precise delivery of heat energy to a target skin lesion being treated. The skin lesion usually vaporizes immediately upon treatment. Electrosurgery can be a cost-effective option for patients who do not require laser treatment. It can be used to treat multiple small skin growths quickly.

In trained hands, electrosurgery is a safe procedure with low risks. It is usually performed under topical (using numbing cream) or local anaesthesia. Potential complications include:

1. Pigmentation colour changes
2. Abnormal wound healing, such as formation of keloid scars

Some growths such as viral warts may recur after treatment. In such cases, the doctor will discuss with you whether another form of treatment is suitable.

The skin on our face is unique. It contains a high density of sebaceous (oil) glands, has a different population of resident bacteria (microbiome) and is exposed to elements of weather. The face is also the most obvious, visual part of our body. Bumps on the face are common, and proper treatment can improve our appearance and self-confidence. It is important, however, that an accurate diagnosis is made first. Skin cancers also most frequently affect the face, and these must be treated properly and differently from benign (non-cancerous) skin growths.

Seborrhoeic keratoses are also called "age-spots" or "liver-spots". These are common, benign growths that can occur anywhere on the body. Seborrhoeic keratoses appear as brown to black bumps with a rough, waxy surface that seem to be "stuck" onto the surface of the skin. They can range from a few millimetres to centimetres in size. Seborrhoeic keratoses are non-cancerous and non-contagious. They occur more frequently as we age.

Seborrhoeic keratoses may be left alone if no treatment is desired. Otherwise, they can be removed by electrosurgery, laser or cyrotherapy.

Sebaceous hyperplasia are enlarged sebaceous (oil) glands that are commonly found on the forehead and cheeks. They appear as skin-coloured to yellowish, soft bumps with a central dimple, and can measure up to a few millimetres in size. Sebaceous hyperplasia become more common with age. Basal cell carcinoma (a form of skin cancer) can sometimes look like sebaceous hyperplasia. If in doubt, it is best to get a dermatologist to examine the bump.

Treatment for sebaceous hyperplasia include electrosurgery or laser. Some patients may also try oral isotretinoin.

Syringomas are benign growths that arise from sweat ducts. They commonly appear around the eyes as small, round, skin-coloured bumps about one to three millimetres in size. Syringomas are more common in women, and can start to appear from adolescence. Syringomas can be removed by electrosurgery or laser.

Milia are tiny cysts that appear as small (usually 1 millimetre) white or yellowish, pearly bumps. They may arise spontaneously, or after some minor injury to the skin. Milia can be removed by simple extraction (where the overlying skin is pricked and the "seed" beneath squeezed out), electrosurgery or laser.

Moles (melanocytic nevi) are collections of pigment cells (melanocytes) in the skin. They can appear as birth, or be acquired over time. Moles can be flat or raised, and vary from skin-coloured, light brown to black in colour.

If a mole shows signs of change, such as increase in size, alterations in shape or colour, or begin to itch or bleed, then they must be brought to the attention of a doctor. A dermatologist will use a dermatoscope (a specialized equipment that allows visualization of colour patterns beneath the skin surface) to examine the mole to exclude melanoma (an aggressive type of skin cancer that arises from melanocytes) or other possible growths. Moles should not be casually removed without first being examined by a doctor, especially if they are changing, because it may lead to a missed diagnosis of skin cancer!

Benign moles can be left alone, or removed by various techniques of surgery or laser surgery.

Xanthelesma are collections of cells which are filled with fat or cholesterol. They appear as yellowish, soft, raised patches around the eyes. Xanthelesma can appear in people with raised or normal levels of cholesterol. They can be removed by minor surgery or laser.

Keloids are firm, pink to red bumps that rise abruptly above the surface of the skin. They are an abnormal form of scar tissue that can occur soon or months after an injury to the skin. Keloids may feel uncomfortable or itchy, and some may continue to grow in size. Common sites of keloid formation include the ears, jaws, chest, shoulders and upper back. Some people may be genetically prone to having keloids.

Keloids are the result of excessive and abnormal scar tissue formation after an initial injury. The exact reason why some people develop keloids is unknown. Common injuries that cause keloids include:

1. Traumatic injuries
2. Burns
3. Acne
4. Chickenpox
5. Piercings
6. Tattoos
7. Surgery
8. Vaccination

People who are prone to keloids should avoid unnecessary injury to the skin, such as piercings. Wounds should be carefully managed to reduce inflammation which may lead to excessive scar tissue formation. Early preventive treatment with silicone gel or sheet may be beneficial.

Treatments for keloids include:

1. Corticosteroid injection

Steroids can be injected directly into the keloid scar. This helps to reduce inflammation and itch, slow the growth of keloids, and induce softening and flattening of the keloid. The amount of steroid that is absorbed into the body is usually minimal. Steroid injections are repeated every 1 to 2 months until satisfactory resolution of the keloid is achieved.

2. Silicone gel or sheets

Silicone gel or sheets applied to the keloid may help it to flatten. This treatment is more effective when use prophylactically before the keloid has formed, or early during scar formation.

3. Cryotherapy

Freezing with liquid nitrogen helps to damage the skin cells that are forming the abnormal scar tissue.

4. Laser

Different types of lasers may be used to ablate (cut out) the keloid, or reduce the vascularity (redness) of a keloid scar.

5. Surgical excision

Large keloids, especially those on the ear, may be removed by surgery. Keloids have a high risk of recurrence after surgery, so treatment should be combined with other modalities such as corticosteroid injection and silicone gel application after the wound has healed.

The medical term for mole is melanocytic nevus (plural: nevi). Moles are formed by aggregation of pigment cells called melanocytes in the skin. They can vary in shape, color and size. Common moles are usually flat or raised, brown to black bumps on the skin. They can appear at birth or be acquired as we grow. Moles are benign (non-cancerous), but may have a small risk of turning into melanoma, an aggressive type of skin cancer.

Be definition, a mole is a benign growth. However, there is a small risk of moles turning cancerous. If you notice changes in your mole, such as in size, shape, outline or colour, it is best that you show it to a dermatologist. A dermatologist will usually examine the mole using a dermatoscopy (a specialized tool that allows visualization of pigment patterns beneath the skin surface) to determine the risk of it being cancerous.

Patients may use the ABCDE mnemonic to check if their mole should raise suspicion of being cancerous. If the mole meets any of the criteria, it is best to show it to a dermatologist.

A - Asymmetry.

B - Border irregularity

C - Colour variability or change

D - Diameter >= 6mm; Different from other moles

E - Evolution or changing

Moles can be removed by surgical excision (cutting followed by stitches), shave excision (a shaving of the top of a mole) or laser. Our specialists at TSN Dermatology will be able to advise you what is the most appropriate treatment, and the benefits and risks of each technique. We will also advise whether the tissue removed should be sent for histology (laboratory analysis) to determine the character of the mole, whether it is benign or cancerous.

Moles should not be casually removed before they are examined by a doctor, because skin cancers can sometimes be mistaken for moles! Inadequate removal of skin cancers may lead to delayed diagnosis, recurrence and further complications later on.

The nail apparatus consists of the nail and its surrounding skin. This structure can be affected by various types of growths and disorders such as ingrown nails. These can give rise to pain and swelling of the affected finger or toe, or a deformed nail. Specialists at TSN Dermatology are trained to recognize nail disorders and perform surgeries on the nail. Nail surgeries are performed under local anaesthesia, and patients will not feel pain during the surgery. After the operation, you will be prescribed painkillers and given supportive dressings to the wound to facilitate healing.

Ingrown nails usually affect the toes, especially the big toe. It is a condition where the sides or corners of a nail digs into the skin at the side or end of the toe. The resulting pain, swelling and pus formation can affect walking and even sleep. Ingrown nails can be caused by ill-fitting shoes, improperly trimmed nails, abnormal nail shapes, or overgrowth of flesh over the nail.

Treatment for very mild cases of ingrown nails includes soaking the affected toe in warm water few times a day, ointments (eg. antibiotics, antiseptics) and oral antibiotics for secondary infection. Moderate cases may require procedures to separate the nail from the flesh, such as insertion of cotton wool or plastic tubes between the nail and the flesh. Severe cases of ingrown nails often require surgery.

Surgery for ingrown nail includes partial nail avulsion (removal of the ingrowing part of the nail), with or without partial matricectomy (permanent destruction of the tissue that gives rise to the ingrowing nail). If the problem is the surrounding flesh growing over the nail, surgery to cut away this excess flesh can be performed.

Post-surgical care includes dressings, painkillers and antibiotics. There is usually significant pain relief once the pressure of the nail biting into the flesh is removed.

Digital mucous (myxoid) cysts present as shiny, round, dome-shaped bumps at the end of the finger or toe, close to the nail. They are thought to come about due to degeneration of connective tissue around the nail, or linked to underlying osteoarthritis (wear and tear) of the joint near the nail. Digital mucous cysts are benign growths, but can press on, and cause deformity of the nail.

Treatment for digital mucous cysts include non-surgical means such as repeated needling and compression, injections into the cyst, cryotherapy, laser and surgery. Different surgical techniques work for different types and locations these cysts, and our specialists at TSN Dermatology will be able to provide further advice.

Nail biopsy involves sampling a bit of tissue from the nail apparatus for diagnostic or treatment purposes. This may be necessary in cases where a growth is seen in the nail, where there is pigmentation of the nail (melanonychia), or nail deformity which is suspected to be caused by a tumour pressing on the nail.

Nail biopsy is performed under local anaesthesia. The nail may or may not need to be removed, sometimes partially or completely.

A skin biopsy is a diagnostic procedure, where a small piece of tissue is removed and sent to the lab for analysis (histology). This helps the doctor to understand what is the cause of a skin problem. It can also help to exclude skin cancer if this is suspected.

Most skin conditions can be diagnosed clinically by a dermatologist without any further tests. Our specialists will advise you if we think a biopsy is necessary. The results of a skin biopsy needs to be correlated with the clinical appearance of the skin problem, and this is best performed by a skin specialist. This is because the biopsy is only a sample of the entire skin problem, and different skin diseases can look the same in the laboratory analysis. Different techniques of biopsy may also affect the accuracy of the test, and a dermatologist is qualified to advise you on choosing the appropriate method.

Skin biopsies can sometimes be both diagnostic and therapeutic. In cases of benign skin lumps where the whole lump is removed for analysis, the skin biopsy also treats the condition since the lump is completely taken out.

Most skin biopsies are performed in the clinic as an office procedure, and only require local anaesthesia. The skin is first anaesthetized using numbing cream or skin injection. A small piece of skin is subsequently removed using a blade or circular punch instrument. The small wound is then stitched up, and usually only one or a few stitches are required. In case a shave biopsy (superficial shaving of the skin) is performed, stitches will not be required and the skin will heal naturally by itself. A simple biopsy often takes less than 15 minutes.

After the procedure, we will provide you with information on how to take care of the wound, dressings, ointments and antibiotics if required. Most skin biopsies do not require painkillers after anaesthesia has worn off. If there are stitches, you will be given an appointment to return for their removal in 7 to 14 days. Our specialists will also update you on the biopsy result at the follow-up visit.

The cost of a simple skin punch biopsy starts from $300, before any laboratory fee. Our clinic follows the surgical fee benchmark set by the Ministry of Health. The cost of a skin biopsy may be claimable from insurance, and we will be able to help you e-file your claims or provide documents to support your claims.

Skin cancers are abnormal growths on the skin. They are the most common type of cancer worldwide, and rank amongst the ten most common cancers in Singapore. Most skin cancers arise due to exposure to ultraviolet radiation in sunlight. Skin cancers are more frequently seen in older people and on sun exposed areas, although they can occur in younger people and covered areas as well. The most common skin cancers are basal cell carcinoma, squamous cell carcinoma and melanoma.

Surgery is the first-line treatment for most skin cancers, and most skin cancers are cured with surgery alone. Treatment usually starts with a skin biopsy to confirm the diagnosis. Depending on the type of skin cancer, our specialists may order other tests such as scans to determine the stage of the cancer. Finally, the doctor will discuss with you the treatment options available. These can range from creams, cryotherapy and electrosurgery for superficial cancers, to surgery, radiation therapy or immunotherapy for advanced cancers. At every step of your management, our specialists will work with you in reaching shared decisions on treatment.

Surgery for skin cancers

Surgery is considered curative for most skin cancers. The options usually include (1) wide excision with pre-determined margins, or (2) Mohs micrographic surgery. Mohs surgery is the gold standard for treatment of high-risk skin cancers, and is available at TSN Dermatology Skin Specialist Clinic. Both types of surgeries are performed as day surgeries, under local anaesthesia.

In wide excision (sometimes called standard excision), the doctor decides the margin of normal tissue around the visible cancer that needs to be removed before surgery. This usually ranges from 4 to 6 millimetres for most skin cancers. After the tissue is removed, the defect on the skin is closed, and the tissue is sent to the laboratory to confirm clearance of the tumour.

Mohs micrographic surgery uses an advanced, layer-by-layer approach that reduces the normal tissue that is sacrificed while increasing the success rate of the surgery. In Mohs surgery, any visible tumour is first removed with a narrow margin of normal tissue. This tissue is sent to the laboratory for analysis using a special method. The Mohs surgeon will then personally examine the laboratory analysis to see if further tissue needs to be removed from the patient. After all cancer tissue are removed, the defect is finally closed. Like standard excision, Mohs surgery is performed as a day surgery (most surgeries can be completed in a day or less) under local anaesthesia.

After surgery, you will be given information on how to care for the wound, dressings, ointments and antibiotics or painkillers if required. Stitches can usually be removed in 7 to 14 days.

Patients who have had a skin cancer are at risk for developing subsequent skin cancers. They should receive regular surveillance from their dermatologist. Our patients are also taught how to perform self-monitoring of their skin for suspicious lesions, and how to practice correct sun protection.

Skin tags are small growths that hang off the skin. They are usually skin coloured or slightly darker, smooth and soft to touch, and range from 1 to a few millimetres in size. Skin tags are commonly found around the skin folds such as the neck, armpits, groin and beneath the breasts. Skin tags are not cancerous or contagious.

Skin tags can be removed if they catch on clothes or if found to be bothersome. One should resist the temptation to remove them by twisting the neck of the tag or tying a string around it, as non-sanitary methods may lead to infection.

Skin tags can be removed using cryotherapy, electrosurgery or laser.

Viral warts are caused by the Human Papillomavirus (HPV). This common virus enters the skin through microscopic breaks in the skin surface, infects the skin cells, and cause them to grow into thick bumps (warts) on the surface of the skin.

Warts are contagious, and one should resist the temptation to pick or scratch them. Warts should be treated to prevent further spread within the patient, or to family members.

There are a variety of methods to treat viral warts. These include:

1. Topical creams

Lotions to treat warts include mild acids (eg. salicylic acid), retinoids (vitamin A derivatives) and immunomodulators. The benefit of lotions include convenience, as most can be applied by the patient at home. However, lotions are usually only effective for small or thin warts, and need to be used for a longer period of time (months) to determine if they are effective. Some lotions cause irritation and may not be tolerated by patients.

2. Cryotherapy

This is the most common treatment employed to treat warts. At TSN Dermatology, we perform cryotherapy using liquid nitrogen, which is colder and more effective than other methods of cryotherapy. Cryotherapy needs to be repeated every 1 to 2 weeks till the wart has completely disappeared. Cryotherapy is a quick office procedure that does not require anaesthesia.

3. Laser surgery

Ablative laser surgery (using CO2 laser) can be performed for stubborn warts. Local anaesthesia is first administered, before the whole wart and some surrounding skin is vaporized using laser. Painkillers may be required after surgery, and there will be a period of wound healing that can take weeks.

4. Surgery

Warts can also be removed by cold-steel surgery using a blade, under local anaethesia. This method is not commonly employed.

5. Immunotherapy

Immunotherapy involves injecting warts with medications that stimulate the immune system to attack the virus and clear the wart. Immunotherapy is a newer form of treatment and has been used to treat warts that are resistant to other forms of therapy. Usually only one wart needs to be injected, to trigger the immune system to attack all other warts.