Hopefully this will help-its from the CPT assistant
Nervous System, Surgery, 64702-64727 (Q&A)
Body: Coding Consultation
Question
Code 64727 describes internal neurolysis. The parenthetical note following this code states that neuroplasty includes external neurolysis. What is the difference between internal and external neurolysis?
AMA Comment
As stated in the usage guidelines for codes 64702-64726, neuroplasty is the decompression or freeing of intact nerve from scar tissue, including external neurolysis and/or transposition. External neurolysis is used to evaluate the nerve to determine if segmental nerve resection and suture are indicated and to enhance regeneration when resection and/or suture are not performed. External neurolysis includes division of perineural adhesions and/or excision of perineural scar tissue.
Some procedures may require internal neurolysis, which involves the microscopic excision of scar tissue from between nerve fascicles to enhance nerve regeneration after nerve injury or suture/repair. Code 64727, Internal neurolysis, requiring use of operating microscope (List separately in addition to code for neuroplasty), should be reported in addition to external neuroplasty when scar tissue is microscopically excised from between the nerve fasicles.