What is a skin and muscle biopsy?
A skin biopsy is a procedure where a small piece of skin is removed for testing.
A muscle biopsy is a procedure where a doctor removes small pieces of muscle tissue from your child (generally the thigh muscle). The muscle biopsy is done using image guidance by an interventional radiologist.
Why is a skin and muscle biopsy done?
Skin and muscle biopsies are typically done to determine or confirm a diagnosis. Your child’s doctor will discuss with you the reason for your child’s biopsy.
Risks of a skin and muscle biopsy for your child
Skin and muscle biopsies are considered low risk procedures. The risks may increase depending on your child's condition, age and health.
The risks of skin and muscle biopsy include the following:
- inconclusive results
- pain
- bleeding
- infection
- injury to muscle, nerve or blood vessel
Visiting the clinic before the procedure
Your child will have a clinic visit with the interventional radiologist before the procedure. During the visit, you should expect:
- A health assessment to make sure your child is healthy and that it is safe to have general anaesthesia and to go ahead with the procedure.
- An overview of the procedure and potential risks as well as a review of the consent form with an interventional radiologist.
- Blood work.
Giving consent before a skin and muscle biopsy
Before the procedure, the interventional radiologist will go over how and why the procedure is done, as well as the potential benefits and risks. They will also discuss what will be done to reduce these risks and they will help you weigh any benefits against the risks. It is important that you understand all of the potential risks and benefits of the skin and muscle biopsy and that all of your questions are answered. If you agree to the procedure, you can give consent for the procedure by signing the consent form. A parent or legal guardian must sign the consent form for young children. The procedure will not be done unless you give your consent.
How to prepare your child for the procedure
Before any treatment, it is important to talk to your child about what will happen. When talking to your child, use words they can understand. Let your child know that medicines will be given to make them feel comfortable during the procedure.
Children feel less anxious and scared when they know what to expect. Children also feel less worried when they see their parents are calm and supportive.
If your child becomes ill within two days before the procedure
It is important that your child is healthy on the day of the procedure. If your child starts to feel unwell or has a fever within two days before the biopsy, let your doctor know. Your child's procedure may need to be rescheduled.
Food, drink and medicines before the procedure
- Your child's stomach must be empty before sedation or general anaesthetic.
- If your child has special needs during fasting, talk to your doctor to make a plan.
- Your child can take their regular morning medicine with a sip of water two hours before the procedure.
- Medicines such as acetylsalicylic acid (ASA), naproxen or ibuprofen, warfarin, or enoxaparin may increase the risk of bleeding. Do not give these to your child before the procedure unless they have been cleared by your child's doctor and the interventional radiologist.
On the day of the procedure
Arrive at the hospital two hours before the planned time of your child's procedure. Once you are checked in, your child will be dressed in a hospital gown, weighed and assessed by a nurse. You will also be able to speak to the interventional radiologist who will be doing the skin and muscle biopsy and the anaesthetist who will be giving your child medication to make them comfortable for the procedure.
During the skin and muscle biopsy you will be asked to wait in the surgical waiting room.
Your child will have medicine for pain
It is important that your child is as comfortable as possible for the procedure. They may be given local anaesthesia, sedation or general anaesthesia. For skin and muscle biopsies, most children are given a general anaesthetic and local anesthesia.
How is a skin and muscle biopsy done?
A skin biopsy and a muscle biopsy can be done at the same time. The doctor will remove a small circular piece of skin (the size of a pea) using a punch biopsy technique. Next, the interventional radiologist will use ultrasound to locate an area in the muscle that can be used for a biopsy. A hollow needle will be inserted through the skin biopsy site and into the muscle. Three or four samples that are 4 mm x 2 cm each in size will be obtained. Samples are sent to the pathology laboratory and assessed. Both biopsy samples (skin and muscle) are generally taken from the outer thigh. Dissolvable stitches are used to close the biopsy site and a small dressing is placed on top. The dressing can be removed after 24 hours.
![Illustration of a skin punch biopsy and a muscle biopsy](/globalassets/assets/skin_muscle_biopsy_en.jpg?width=356&quality=60)
After the skin and muscle biopsy
Once the skin and muscle biopsy is complete, your child will be moved to the recovery area. The interventional radiologist will come and talk to you about the details of the procedure. As soon as your child starts to wake up, a nurse will come and get you.
There will be a small dressing on the biopsy site. The dressing needs to stay on for 24 hours.
Results
Your referring doctor will receive the results of your child’s skin and muscle biopsy. You will need to make an appointment with them to discuss the results.
Going home
Most children who have a skin and muscle biopsy go home the same day. Your child will be ready to go home about four hours after the biopsy. Occasionally some children will stay overnight after a skin and muscle biopsy for observation.
For more details on how to care for your child after the skin and muscle biopsy, see Skin and muscle biopsy: Caring for your child at home after the procedure.
If you have any concerns in the first 48 hours, call the IGT clinic at (416) 813- 7654 ext. 201804 and speak to the clinic nurse during working hours or leave a non-urgent message with the IGT clinic nurse.
If you have concerns and it is after working hours, see your family doctor or go to the nearest Emergency Department or call the Hospital for Sick Children switchboard at (416) 813-7500 and ask them to page your referring doctor or the Interventional Radiology fellow on call.
For more information on fasting see Eating and drinking before surgery.
For more information on preparing your child for their procedure see Coming for surgery.