Neurosurgery Coding Alert

An anatomy lesson will point you in the right direction every time. How do you tell the difference between 61790 (Creation of lesion by stereotactic method, percutaneous, by neurolytic agent [e.g., alcohol, thermal, electrical, radiofrequency]; gasserian ganglion) and 61791 (... trigeminal medullary tract)? That's the question a Neurosurgery Coding Alert reader posed when she wrote, "What is the differencebetween the gasserian ganglion and trigeminal medullary tract, and how do you determine which code to use?" The answer lies in knowing your anatomy so you can assign codes accordingly. 1. Know Your Nerve Anatomy Understanding the nerve branches and how they relate to each other is your first step in distinguishing between 61790 and 61791. Here's what you need to know: • The trigeminal nerve provides sensation to the face. It's the fifth (and largest) cranial nerve, also called the fifth nerve or simply V. • The trigeminal nerve nucleus is [...]