Therapath Neuropathology

Muscle biopsy procedure

Biopsy kits

Muscle biopsy kits include the following components:

  • Foam insulating container and shipping box
  • Pre-paid shipping label and requisition form
  • Wood support (for EM specimen)
  • Coolant pack (store in a freezer no colder than -20° C)
  • Transport bag holding:
    • Vial 1: Empty vial for fresh, unfixed tissue
    • Vial 2: 10% neutral buffered formalin
    • Vial 3: 3% glutaraldehyde in Sorensen’s buffer

Upon receipt, refrigerate (4-8° C) the vial of glutaraldehyde fixative (yellow cap) and store the remainder of the vials at room temperature (22-25° C). The glutaraldehyde vial may be removed from the cold and kept at room temperature for the duration of the biopsy procedure. After addition of biopsy specimens, the entire box containing all vials should be prepared for shipment and kept cool with the provided coolant packs.

Sample Collection

Adults: Excise a 1 cm x 1 cm x 2.5-3.0 cm longitudinal length of muscle. Do not stretch the muscle and handle gently only by the ends.

Young Children: Similarly excise and handle a 0.5 cm x 0.5 cm x 2.0-2.5 cm length of muscle.

Sample Preparation

Divide the biopsy, place into vials as follows, and cap all vials tightly.

A) Segment 1 (for enzyme histochemistry and immunohistochemistry)
1 cm cube (adult) or 0.5 cm cube (young children):
Remove the single 2” × 2″ gauze pad from its pouch in the sterile accessory kit and slightly dampen it with normal saline (not provided). Manually squeeze out excess saline until the gauze is just moist (not wet). Unfold the gauze to the original size, place the muscle segment near one edge and roll the gauze around the muscle to wrap it. Make a shallow fold at both ends to completely enclose the tissue. Carefully insert the wrapped biopsy vertically into the empty vial 1 (green label) without squeezing or pressure on the tissue specimen.*

*Do not use more than the one 2” × 2” gauze pad to wrap the biopsy, or make too many overlapping folds, or use a biopsy segment that is wider than 1 cm cube as the resulting extra thickness may cause excessive compression of the tissue during insertion into the vial opening.

b) Segment 2 (for routine histology)
1 cm cube (adult) or 0.5 cm cube (young children):
Place this segment into vial 2 (white cap) containing 10% neutral buffered formalin.

c) Segment 3 (for EM)
No larger than 0.3 cm x 0.3 cm x 0.5 cm:
Lay this segment onto the dry wood support provided. No further anchoring is necessary. Insert the support into vial 3 (yellow cap) containing 3% glutaraldehyde, making sure that the muscle is immersed in the fixative.

Preparation for Shipment

  1. Complete the adhesive patient ID labels with patient name and biopsy site. Affix an ID label to each vial and orient the ID labels vertically in the empty space on the vials behind the existing vial label.
  2. Place the tightly capped vials firmly into the vial box. Seal the box of vials and white absorbent pad in the provided biohazard 95kPA air-transport plastic bag, pressing as much air out of the bag as possible before sealing. Bag expansion from excess air may prevent the coolant packs from fitting into the foam box.
  3. Place the sealed 95kPa bag of vials into the center of the foam box, retrieve the 2 coolant packs from the freezer and place one on each side of the vials. Close the foam box lid firmly and seal with the tape band provided.
  4. Enclose the completed requisition form in the plastic bag, place on top of the foam container, and seal the bag and container inside the outer shipping box. Keep the box upright and seal it in the pre-labeled, pre-paid FedEx or UPS UN3373 return pouch.
  5. Call FedEx (800-463-3339) or UPS (800-823-7459) before 2 pm on the day of biopsy to schedule a pickup.