Peripheral nerve biopsies are undertaken to investigate neuropathy and vasculitis using a range of diagnostic techniques. Electron microscopy is generally required on a portion of the tissue.1-3
Record the patient identifying information and any clinical information supplied together with the specimen description as designated on the container. See overview page for more detail on identification principles.
Clinical information for any nerve biopsy should include the following (a standard proforma for the clinician will assist in ensuring relevant information is collected):
- Information about the biopsy site and laterality
- Age at biopsy (essential)
- Details of onset, distribution and progression of the disorder
- Involvement of other organs
- Results of nerve conduction studies and electromyography or MRI of brain, spinal cord and adjacent nerve roots or muscle (if performed)
- Drug history
- Occupational exposure/s
- Past and current personal and family medical history
- Plasma creatinine kinase (CK) level (essential)
- Plasma and CSF lactate levels, other biochemical investigations and results of brain, spinal cord and adjacent nerve roots or muscle MRI (if performed).
- Non-routine fixation (not formalin), describe.
- Special studies required, describe.
- Ensure samples are taken prior to fixation.
- The recommended length of the biopsied nerve segment is at least 40mm but 50-60mm is considered optimal. Removal of a shorter segment with be less useful diagnostically but will leave an identical sensory deficit.
- Submission of nerve segments in formalin (10%) and glutaraldehyde (2.5-6%) within 5 minutes is recommended. Freezing an unfixed segment is optional.
See general information for more detail on specimen handling procedures.
Inspect the specimen and dictate a macroscopic description.
Orientate and identify the anatomical features of the specimen.
Record additional orientation or designation provided by operating clinician:
- Method of designation (e.g. suture, incision)
- Featured denoted
Photograph the intact specimen if required.
Describe the following features of the specimen:
Record as stated by the clinican
- Nerve biopsy
- Other, describe
Anatomical components included (more than one may apply) and specimen dimensions (mm)
Describe and measure the anatomical components present.
- Nerve in two dimensions, length x width
- Other, describe
- Disrupted/fragmented/opened, describe
Dissect into segments for light and electron microscopy. Another segment may be retained for frozen sections, molecular biology or biochemical analysis if required.1-3
A suggested protocol:
Subdivide the specimen and submit sections of the nerve for processing:
Electron microscopy –transfer to 2.5% buffered glutaraldehyde with a weight attached
At least 15 mm for teased nerve fibre preparations
A transverse section for electron microscopy
Routine light microscopy –transfer to neutral buffered formalin
1 to 4 transverse sections
Frozen storage/sections if required -a transverse section for snap freezing (optional)
Submit remainder of specimen (not required for electron microscopy) in its entirety for processing.1-3 Lens paper, biopsy pads or similar are required to prevent loss of tissue during processing.
Record details of each cassette.
An illustrated block key similar to the one provided may be useful.
Block allocation key
No. of pieces
Dr Barbara Koszyca and Kathy Cash for their contribution in reviewing and editing this protocol.
Dawson TP, Neal JW, Llewellyn L and Thomas C. Neuropathology Techniques. Hodder Arnold, London, 2003.
Lester SC. Manual of Surgical Pathology, Saunders Elsevier, Philadelphia, 2010.