Percutaneous Procedures Microvascular
Percutaneous procedures have, in general terms, a 60 to 80 percent rate of providing long-term relief. In many cases, if pain recurs, these procedures can repeated. There are three types of percutaneous procedures, each of which involves inserting a needle through the cheek into or next to the nerve as it passes through the base of the skull. The three techniques vary according to how the nerve is treated once the needle is in position. These procedures are usually performed on an outpatient basis, oftentimes requiring only intravenous sedation rather than general anesthesia. Facial numbness, usually in the part of the face affected by the pain, is common after these procedures, but most patients report the numbness is much more tolerable than the pain. Percutaneous procedures include:
Glycerol Injection (percutaneous glycerol rhizotomy or PGR)
This procedure is performed by inserting a needle through your cheek, through the base of the skull and into an opening in the skull where a small sac of spinal fluid surrounds the trigeminal nerve ganglion (where the trigeminal nerve divides into three branches). Once radiographic images have confirmed the location, your doctor injects a small amount of sterile glycerol which damages the nerve and blocks pain signals.
In this procedure, your doctor inserts a needle through your cheek, through the base of the skull and positions the needle tip adjacent to the trigeminal nerve. A thin flexible tube called a catheter with a balloon on the end is then slipped through the needle. When the balloon is inflated for a brief period of time, it provides enough pressure to damage the nerve and block pain signals.
Thermal (radiofrequency or RF) Rhizotomy
In this procedure, once the needle in positioned within the nerve inside the skull, a special device is used to generate heat at the tip of the needle. This burns the inside of the nerve, reducing its sensitivity and blocking pain signals.