Neurosurgery Coding Alert

Question: During a hemicraniectomy, 61542, the neurosurgeon implanted the bone flap in the abdominal wall to keep it viable for cranial reconstruction at a later time. How should this be coded? Should modifier -22 be appended to the hemicraniectomy code?

Iowa Subscriber

Answer: There is no specific code for the implantation of a bone flap in the abdominal wall. You are more likely to get paid for this by billing 64999 (unlisted procedure, nervous system) with a separate charge rather than adding modifier -22 (unusual procedural services) to 61542 (craniotomy with elevation of bone flap; for total hemispherectomy). If modifier -22 is used, youre limited to an additional percentage (typically 20 percent) of the original amount which may not cover the extra work performed. Also, the choice of 64999 is supported in this case because the implantation was a separate component of the overall procedure. The -22 would have been appropriate if reimbursement were being sought because the neurosurgeon faced a degree of difficulty above and beyond what is normally encountered.