Surgical Excision

What is excision?

Excision refers to removal of a skin lesion by completely cutting it out.

Why do skin lesions have to be excised?

A common reason why skin lesions are excised, is to fully remove skin cancers such as basal cell carcinoma, squamous cell carcinoma or melanoma. If the cancer is not cut out it may spread to the surrounding skin and to other parts of the body (metastasise).

Other reasons why a lesion may be removed include for diagnosis, cosmetic appearance, if it is symptomatic (eg tender or prone to being knocked), or to remove an inflamed or frequently infected cyst.

Will I have a scar?

It is impossible to cut the skin without scarring in some way, so you will always have some sort of scar. The Doctor will excise the lesion and repair the wound in a way that will keep the scar to a minimum.

Some people have an abnormal response to skin healing and these people may get larger scars than usual (keloid or hypertrophic scarring).

What is involved in excision of a skin lesion?

The doctor will explain to you why the skin lesion needs excision and the procedure involved. You may have to sign a consent form to indicate that you understand and agree to the surgical procedure. Tell your doctor if you are taking any medication (particularly aspirin, clopidogrel, dabigatran and warfarin, which could make you bleed more), or if you have any allergies, medical conditions, or a pacemaker or implanted defibrillator. Remember, to tell your doctor about any over-the-counter supplements or herbal remedies as a number of these can also lead to abnormal bleeding.

The most common type of excision is an elliptical excision. The ellipse is often designed so that the resulting scar runs parallel with existing skin creases. This usually provides a wound under less tension and orientates the scar in a direction which is less noticeable to the eye.

The area to be excised is marked with a surgical marker. A local anaesthetic injection will rapidly numb the area of skin involved and keep it numb during the procedure. The doctorwill then cut around and under the lesion with a scalpel and sharp scissors along with an appropriate margin of normal surrounding tissue. The lesion is placed in formalin ready to go to the pathology laboratory. Here, a pathologist will process and examine the specimen under the microscope, and provide your doctor with a report a few days later.

There may be some bleeding in the area from where the lesion has been removed during the surgery. The doctor may coagulate the blood vessels with a cautery. This can make a hissing sound and a burning smell, but will not be felt.

The edges of the ellipse will then be sewn together to make a thin suture line. This type of wound closure is called primary closure. There may be two layers of sutures (stitches) a layer underneath that is absorbable and a layer of sutures on the surface which will need to be removed in 4-14 days. Occasionally special skin glue is used to join the edges together, instead of sutures.

A dressing may be applied and instructions will be given on how to care for your wound and when to get the stitches out.

 

FLAP Closure

What is a skin flap?

A skin flap is a type of wound closure. A local skin flap consists of skin taken from an adjacent area and moved to fill the surgical defect often created from the removal of a skin lesion such as skin cancer. Flaps differ from skin grafts in that a flap is transferred with an intact blood supply and remains connected to its origin, while a graft is a transfer of tissue which has been completely removed from its origin and therefore relies entirely on the recipient site for its blood supply.

When is a flap necessary?

A skin flap is required when the injury or area that has lost tissue is too big for the edges to be brought together directly. The flap covers the area and depth of the wound. The flap continues to be fed by the same blood supply from where it was taken, until new blood vessels grow from the recipient site and the wound heals completely.

Some flaps known as interpolation flaps are performed in two stages. In the first stage the skin flap is removed from its original location and sewn into the defect leaving a bridge of tissue between the two areas (the flap pedicle). The pedicle supplies the flap with blood for a couple of weeks until the second stage when the pedicle is able to be cut and sewn in to complete the repair.

What are the benefits of using a skin flap to close a wound?

Where a wound is unable to be repaired using a primary closure (or secondary intention healing) a flap provides the benefit of supplying tissue of a similar appearance and thickness to that of the tissue which has been removed. This means the ultimate cosmetic result is usually superior to that of a skin graft.

Skin flaps also often heal faster than skin grafts, and usually do not require the creation of a separate wound in another location. Having said this, sometimes another repair option such as skin grafting is preferable in certain situations and your surgeon will discuss this with you.

What is involved in having a skin flap?

Your doctor will explain to you why a skin flap is required and the type of skin flap you will need. He will explain the procedure involved, including the area of the body from where the flap will be taken, and common complications. Most local skin flap surgery is performed under local anaesthesia. Your doctor will explain to you why the skin lesion needs excision and the procedure involved. You may have to sign a consent form to indicate that you understand and agree to the surgical procedure. Tell your doctor if you are taking any medication (particularly aspirin, clopidogrel, dabigatran and warfarin, which could make you bleed more), or if you have any allergies, medical conditions, or a pacemaker or implanted defibrillator. Remember, to tell your doctor about any over-the-countersupplements or herbal remedies as a number of these can also lead to abnormal bleeding.

The procedure may create two wound sites, the site receiving the flap and the site where the skin flap was taken from. However, aside from interpolation or distant flaps, these two sites are usually immediately adjacent, and will be dressed under the one dressing. Your wound may be tender 1-2 hours after the excision when the local anaesthetic wears off.

Leave the dressing in place for 48 hours or as advised by your doctor. Avoid strenuous exertion and stretching of the area until the stitches are removed and for some time afterwards.

If there is any bleeding, press on the wound firmly with a clean folded towel without removing the existing dressing or looking at it for 20 minutes. If it is still bleeding after this time, seek medical attention.

Keep the wound dry for 48 hours. You can then gently wash and dry the wound. A small amount of pinkness and tenderness to touch around the wound edges is normal but, if the wound becomes increasingly red or painful, consult your dermatologist promptly - it could be infected and need a course of antibiotics.

Usually stitches are removed 5-10 days after the operation. The scar will initially be red and raised but usually reduces in colour and size over several months.

Occasionally, your doctor may suggest a secondary procedure to further improve the appearance of the skin flap some weeks to months after the area has healed. This may require subtle surgical movement or flattening of the tissue, or resurfacing with a laser.

Skin Graft

What is a skin graft?

A skin graft consists of skin taken from another part of the body and applied to the site where skin is missing. This may follow surgical removal of a skin cancer or an injury such as a burn or other trauma. A skin graft is a free piece of tissue without its own blood supply (as compared with a skin flap) and therefore its survival relies completely on a nutrients from the wound bed on which it is placed.

Why do you need a skin graft?

A skin graft is required when the area of skin loss is too big to be closed using local skin and stitches alone. The skin graft covers the wound and attaches itself to the cells beneath and begins to grow in its new location. If a skin graft wasn't performed, the area would be an open wound and take much longer to heal.

What is involved in having a skin graft?

Your doctor will explain to you why a skin graft is required, and the procedure involved. You may have to sign a consent form to indicate that you understand and agree to the surgical procedure. Tell your doctor if you are taking any medication (particularly aspirin, clopidogrel, dabigatran and warfarin, which could make you bleed more), or if you have any allergies, medical conditions, or a pacemaker or implanted defibrillator. Remember, to tell your doctor about any over-the-counter supplements and herbal remedies as a number of these can also lead to abnormal bleeding.

After the excision (excision biopsy), your dermatologist will measure the area of the wound to know what size to make the skin graft. A piece of skin will be shaved or cut from another part of your body (e.g. leg or arm) that is large enough to cover the wound. When possible, skin of similar thickness and colour will be selected.

The piece of skin (the graft) will be applied to the wound and is usually secured in place with stitches. A special dressing will be applied directly over the skin graft and often sutured in place. A outer pressure dressing will then be applied to protect the wound.

Usually this dressing is left in place for approximately seven days until you see the doctor or nurse again. Make sure you have received instructions on how to care for the wound and when to get the stitches out. It is important to limit movement of the area for 2-3 days to allow time for the graft to adhere and develop a blood supply from the wound bed.

Will I have a scar?

It is impossible to cut the skin without scarring of some degree. The final cosmetic result of a skin graft depends on many factors including the type of skin graft, the location, the size and depth of the wound, and patient factors. Because skin grafts are effectively a patch without their own blood supply and sometimes of less thickness than the wound they are applied to, the final appearance may not be as close to normal as it would be if the wound was able to be closed in a straight line or with a skin flap. The have a tendency to look paler and flatter than the surrounding skin with time.

You will have two scars, the scar where the skin graft has been applied and the scar from where the skin graft was taken (donor site). The donor site for a full thickness skin graft will usually be closed in a straight line with stitches. The donor site for a split thickness graft however will consist of a superficial graze and will heal itself more slowly (initially under a special dressing). This grazed area can often be tender post-operatively and require some oral pain relief such as paracetamol.

Some people have an abnormal response to skin healing resulting in larger scars than usual (keloid or hypertrophic scarring).

What are the types of skin grafts?

Split skin grafts
This type of skin graft is taken by shaving the surface layers (epidermis and a variable thickness of dermis) of the skin with a large knife called a dermatome. The shaved piece of skin is then applied to the wound. This type of skin graft is often taken from the leg. A split skin graft is often used after excision of a lesion on the lower leg.

Full thickness skin grafts
This type of skin graft is taken by removing all the layers of the skin with a scalpel (a Wolfe graft). It is done in a similar way to skin excision. The piece of skin is cut into the correct shape, then applied to the wound. This type of skin graft is often taken from the arm, neck or behind the ear. It is often used after excisions on the hand or face.

How do I look after the wound following skin grafting?

You will have two wounds, the site of the original lesion and the site where the skin graft was taken from (donor site).

Your wounds may become tender an hour or two after the excision when the effect of the local anaesthetic wears off.

Skin grafts are very fragile and great care must be taken when looking after them. Leave the dressing in place as advised by your dermatologist. Avoid strenuous exertion and stretching of the area until the stitches are removed and for some time afterwards.

If there is any bleeding, press on the wound firmly with a folded towel for 20 minutes (without removing the original dressing). If it is still bleeding after this time, seek medical attention. Do not rub the area as this may disturb the graft.

Keep the wounds dry until your doctor advises that you can wash them. If the wounds become red or very painful, consult your doctor: they could be infected.

Does the skin graft always take?

Sometimes the skin graft does not survive the transfer to the new site. This usually happens within the first two weeks after the procedure. It can happen for a variety of reasons including the accumulation of blood or fluid underneath the graft, and/or wound infection. If this happens, your doctor will inform you what further treatment is required - a repeat skin graft procedure may be required or the wound may be dressed regularly and left to slowly heal on its own. It is quite normal for the graft to appear dark and crusted on the surface when the dressings are removed early on. This does not necessarily mean it has failed.