Is a Nerve Biopsy?
A nerve biopsy is a procedure where a small sample of a nerve
is removed from your body and examined in a laboratory.
a Nerve Biopsy Is Done
Your doctor may request a nerve
biopsy if you are experiencing numbness, pain, or weakness in your extremities.
You might experience these symptoms in your fingers or toes.
A nerve biopsy can help your
doctor determine whether your symptoms are caused by:
- damage to
the covering of a nerve (called the myelin sheath)
- damage to
the small nerves
of the axon in the nerve cell (the fiber-like extensions of the cell that help
(inflammatory nerve conditions)
Numerous conditions and nerve
dysfunctions can affect your nerves. Your doctor may order a nerve biopsy if they
believe you may have one of the following conditions:
peroneal nerve dysfunction
median nerve dysfunction
- radial nerve
- tibial nerve
Are the Risks of a Nerve Biopsy?
The major risk associated with a
nerve biopsy is long-term nerve damage. But this is extremely rare since your surgeon
will be very careful when choosing which nerve to biopsy. Typically, a nerve
biopsy will be done on the wrist or the ankle.
According to New York University
Medical Center, it’s common for a small area around the biopsy to remain numb
for about six to 12 months after the procedure. In some cases, the loss of
feeling will be permanent. But because the location is small and unused, most
patients are not bothered by it.
Other risks might include minor
discomfort after the biopsy, allergic reaction to the anesthetic, and
infection. Talk to your doctor about how to minimize your risks.
to Prepare for a Nerve Biopsy
Biopsies do not require much
preparation on the part of the patient. But depending on your condition, your
doctor may ask you to:
- undergo a
physical examination and complete medical history
- stop taking
any medications that affect bleeding (including pain relievers, anticoagulants,
and certain supplements)
- have your
blood drawn for a blood test
(including liquids) for up to eight hours before the procedure
- arrange for
someone to drive you home
a Nerve Biopsy Is Performed
Your doctor may choose from three
types of nerve biopsies, depending on the area where you are having problems.
These include: sensory nerve biopsy, selective motor nerve biopsy, and
fascicular nerve biopsy.
For each type of biopsy, you will
be given a local anesthesia that numbs the affected area. You will remain awake
throughout the procedure. Your doctor will make a small surgical incision and
remove a small portion of the nerve. They will then close the incision with
The portion of nerve sampled will
be sent to a laboratory for testing.
Sensory Nerve Biopsy
For this procedure, a 1-inch patch
of a sensory nerve is removed from your ankle or shin. This could cause
temporary or permanent numbness to part of the top or side of the foot, but is
not very noticeable.
Selective Motor Nerve Biopsy
This is done when a motor nerve
(one that controls a muscle) is affected. A sample is typically taken from a
nerve in the inner thigh.
Fascicular Nerve Biopsy
During this procedure, the nerve
is exposed and separated. Each section is given a small electrical impulse to
determine which sensory nerve should be removed.
a Nerve Biopsy
After the biopsy, you’ll be free
to leave the doctor’s office and go about your day. It may take up to several
weeks for the results to come back from the laboratory.
You’ll need to care for the
surgical wound by keeping it clean and bandaged until your doctor takes out the
stitches. Make sure to follow your doctor’s instructions in caring for your
When your biopsy results are back
from the lab, your doctor will schedule a follow-up appointment to discuss the
results. Depending on the findings, you may need other tests or treatment for