Overview of Excisional Biopsy
A skin biopsy is a procedure that dermatologists (skin doctors) use to help identify different skin conditions and plan the right treatment. The procedure involves removing a small piece of skin to examine it closely. There are several ways this can be done, such as shaving, using a special tool called a curette, making a small cut, or making a larger cut to remove an entire skin lesion.
This article focuses on the last type, known as an excisional biopsy. This technique involves completely removing a single skin lesion – an abnormal area of skin like a lump or patch. This type of biopsy is really useful for checking out skin tumors (abnormal tissue growth), inflammation (swelling and redness caused by your body’s defense system), and lesions that extend into the layer of skin known as the dermis.
It’s rare to have complications from an excisional biopsy, and this can be avoided by proper evaluation before and during the procedure combined with the correct surgical techniques.
An excisional biopsy gets us a sample of skin for a lab test that helps to identify different diseases. However, the biopsy result should always be compared with what the doctor observes during the medical examination for an appropriate and final diagnosis.
Anatomy and Physiology of Excisional Biopsy
When preparing for surgery, careful planning is key not only to avoid any issues during and after surgery, but also to ensure the best possible cosmetic result. Certain skin features and patterns, like natural skin wrinkles and units of skin that match in look and function, should be kept in mind to help hide any scars that might result from surgery.
The doctor may apply pressure to the skin to change the tightness of the surgical area in order to find these natural skin wrinkles. For surgeries near a joint or on the face, they could ask the patient to move the joint in every direction it can go, or to make facial expressions such as smiling or frowning. This helps the doctor see how the skin moves and changes, which can then guide their surgical plan.
Why do People Need Excisional Biopsy
An excisional biopsy is a procedure that can help doctors accurately identify and diagnose certain types of skin issues. These issues could include abnormal skin growths, inflammatory skin conditions, or any problem that affects the deeper layers of skin or the fat layer beneath the skin. This type of biopsy is particularly useful for suspected cases of melanoma, a type of skin cancer. This is because the information gathered from viewing the depth of the suspicious skin growth can provide vital clues for diagnosis and to help make predictions about the course of the disease.
When a Person Should Avoid Excisional Biopsy
Choosing where to take a biopsy, which is a small sample of tissue, can depend on where the abnormal area, or lesion, is found in your body. However, if a condition affects many parts of the body, doctors try to avoid certain areas. This is because some places may not show clear results under microscope examination, or might not look good after biopsy.
For instance, areas below the knee are riskier because they are more likely to catch an infection or not heal properly after a biopsy. The back can also be a difficult place to have a biopsy because the skin tends to stretch and change shape. Other tricky spots to have a biopsy include the middle of the face and the inner part of your arm.
To avoid potential issues with healing or looks, doctors usually prefer to take biopsy samples from the body’s trunk or limbs. Excisional biopsies, where an entire lesion is removed, often happen in these locations. Innovative techniques like Mohs micrographic surgery have also made it possible to use this type of biopsy on skin conditions more often.
Equipment used for Excisional Biopsy
To prepare for the medical procedure, your doctor will gather certain tools. These include:
* A small needle attached to a syringe, filled with a local anesthetic. This is a medication that causes numbness in the specific area where the doctor will work, so you won’t feel pain during the procedure.
* A surgical pen, which is a special pen used to mark the area on your body where the doctor will make an incision or perform the procedure.
* An antiseptic solution, which is a liquid that kills bacteria and other germs to prevent infection.
* Surgical drapes, which are sterile sheets that cover you during the procedure to keep the area clean.
* Gauze, a type of woven fabric that absorbs blood and other body fluids.
* Clean surgical gloves that the doctor will wear to keep everything sterile.
* A scalpel, a small surgical knife used to make the incision.
* Toothed pickups, that help hold and move tissues during surgery.
* Blunt-tipped scissors, used for cutting tissues without causing unnecessary damage.
* A cautery device, an instrument that uses heat to stop bleeding by sealing blood vessels.
* Needle driver which is used by the surgeon to hold the suturing needle while they are stitching up the wound.
* Absorbable and non-absorbable sutures. Sutures are the ‘threads’ used to stitch or close the wound. Absorbable sutures dissolve on their own over time, non-absorbable ones need to be removed later.
* Suture scissors, specialized scissors used for cutting sutures.
Who is needed to perform Excisional Biopsy?
An excisional biopsy is a procedure where a doctor removes a small piece of tissue from your body to examine it more closely. Usually, only one doctor is needed to perform this biopsy, depending on where on your body the tissue is taken from. But, a second person who assists the doctor might also be involved. This assistant helps the doctor by getting necessary materials, making sure the area being operated on stays clean, and cutting threads used to stitch the wound closed after the biopsy. This can make the whole process go more smoothly and efficiently.
Preparing for Excisional Biopsy
The process of planning for a surgical biopsy involves identifying and marking the area around the problem area appropriate for surgical removal. The surgeon marks two small triangles on each side of the problem area in a specific direction. This forms an elongated oval shape, intending to minimize or get rid of extra tissue at the end of the removal. This method helps to avoid creating bulgy scars when the surgical site is closed. The final scar typically appears long and linear and follows the natural lines of the skin.
Local anesthesia, which is medicine to numb a specific part of the body, is often used for skin biopsies. The anesthetic commonly used is 1-2% lidocaine, with or without a substance called epinephrine. Epinephrine helps in reducing bleeding, extending the duration of numbness, and reducing the chances of side effects caused by the anesthesia. Also, neutralizing the acid in the anesthetic with sodium bicarbonate can help to decrease the pain when the solution is injected. To lessen discomfort on the patient’s end, the doctor might pinch the area or use a small needle for the injection, and try to avoid multiple injections on the skin. The injection happens very slowly directly into the skin or under the skin. While the medicine acts almost immediately, it might take up to fifteen minutes for the substance to fully constrict the blood vessels if epinephrine is added.
After the anesthesia is administered, the patient is positioned comfortably and the doctor ensures there’s good lighting and the height is right for the surgery. The area for surgery is cleaned with an antiseptic solution and then covered with a drape. Special attention is given to areas with hair; the hair might be trimmed or secured away from the surgical area to keep the area clean.
Before the procedure, the surgeon ensures their hands are thoroughly cleaned and dried. There’s usually no need to scrub the hands as with major surgeries, but the surgeon makes sure to maintain cleanliness. Although wearing a face mask isn’t necessary, surgical gloves are worn throughout the procedure and kept clean. There’s ongoing discussion about whether the gloves need to be sterile or not, but recent studies show no significant difference in infection rates when comparing sterile and clean surgical gloves.
How is Excisional Biopsy performed
When a surgeon needs to make a cut in your skin to remove something, they often do so in a shape that looks like an oval or “ellipse”. They carefully start the cut at the pointy end of the oval, and then keep the cut smooth and straight as they follow the curve. To help keep everything steady, they’ll use their other hand to gently pull the skin taut (tight). After they’ve made the cut on one side, they’ll do the same thing on the other side.
To keep track of what they’ve cut, they might use a special kind of thread that won’t dissolve or they might make a small cut at a specific spot. They’ll use a special tool with teeth, sort of like a comb, to lift up the cut skin so they can carefully remove what’s underneath (like a mole, for example) with a knife or scissors. They’ll try to keep the cut as straight and smooth as possible.
Once they’ve made the cut, there might be some bleeding. To stop it, they can apply pressure or use tools that use heat or electricity. Sometimes, if the cut is too wet, they’ll need to blot it dry before they can use electricity to stop the bleeding. If there are bigger blood vessels involved, they might need to use special dissolvable thread to tie them off.
To help the cut edges come together better or to lessen the pull on the cut, they might also gently lift and separate the tissue around it. They need to be careful though so they don’t harm anything else in the area.
After they’ve finished with the cutting and removing, they need to close the cut. They’ll do this in two layers. The first layer, which is deep under the skin, uses a special kind of thread that will dissolve over time. These stitches help to fill in any gaps, lower the pull on the skin edges, and help the wound edges to look puffed-up or “everted”. If the wound isn’t being pulled tight, they’ll start with the first deep stitch in the middle and then add more halfway between the middle and the ends, splitting the remaining distance in half each time. If the wound is being pulled tight, they’ll put the stitches in at the ends of the wound first, and then add more closer and closer to the middle. This helps lessen the pull as they add more stitches.
The second layer of stitches is at the surface of the skin. They’ll use a special thread for this layer that won’t dissolve, so these stitches will need to be taken out after one to two weeks once the wound has had time to heal. If the skin edges of the wound fit together well and there’s little or no pull on the wound, they might use special tapes or glue instead of stitches.
Possible Complications of Excisional Biopsy
There might be some problems after surgery, including:
* Bleeding where the surgery happened
* Hematoma, which is a pocket of blood that’s clotted or partially clotted
* Infection where the surgery happened
* Damage to the nerves
To stop too much bleeding or hematoma from happening after surgery, your doctor might use techniques to stop bleeding during the surgery and apply pressure dressings and ice afterwards. The chance of getting an infection mostly depends on how well the patient takes care of the wound; cleaning it and changing the bandage every day is important. If the patient is at a high risk of infection, the doctor might provide preventative antibiotics.
What Else Should I Know About Excisional Biopsy?
Skin biopsies are important tools for correctly identifying a range of skin conditions, and they help doctors plan the right treatment for you. When your doctor needs to do a deeper examination of skin growths, inflammation, or skin lesions, they might perform an excisional biopsy. This type of biopsy involves removing the entire suspected area, not just a portion of it, for further testing.
