Use of a Laryngeal Mask Airway Decreases Radiation Exposure During Computed Tomography-Guided Percutaneous Glycerol Rhizotomy for Trigeminal Neuralgia.

BACKGROUND: We have been using computed tomography (CT) guidance for percutaneous glycerol rhizotomy (PGR) for the last 7 years. As a quality improvement exercise, we recently began using general anesthesia (GA) with the use of a laryngeal mask airway (LMA) because of our perception that the procedure went faster and that there was less radiation exposure because of less patient movement. We aim to compare PGR radiation exposure and procedural time between patients receiving local anesthetic with sedation and those receiving GA/LMA. METHODS: A single-center historical cohort study was performed using patients treated with PGR between 2017 and 2019. Ninety-two surgeries were conducted during the study period: 64 surgeries had local anesthetic with intravenous sedation, and 28 surgeries had deeper anesthetic with LMA. Data analyzed included the number of CT sequences obtained, needle placement time, and total radiation dose. RESULTS: Use of GA/LMA resulted in a 23% decrease in mean radiation dose (565.5 vs. 436.1 µGy × cm, P = 0.014), number of CT sequences required (7.4 vs. 5.7, P = 0.003), and needle placement time (12.8 vs. 9.8 minutes, P = 0.006). Additionally, 10 patients underwent multiple glycerol rhizotomies during the collection period with both anesthetic types being used at least once. Seven of 10 patients (70.0%) had a reduction in total radiation dose, number of CT sequences obtained, and needle placement time when GA/LMA was used. There were no procedure- or anesthetic-related complications in this patient cohort. CONCLUSIONS: The use of GA/LMA during PGR is associated with decreased radiation exposure without increased anesthetic complications.

Computed Tomography Guidance for Percutaneous Glycerol Rhizotomy for Trigeminal Neuralgia.

BACKGROUND: Percutaneous glycerol rhizotomy (PGR) is a well-described treatment for trigeminal neuralgia; however, the technique in using surface landmarks and fluoroscopy has not drastically changed since being first introduced. In this paper, we describe a protocol for PGR using computed tomography (CT) guidance based on an experience of over 7 yr and 200 patients. OBJECTIVE: To introduce an approach for PGR using CT guidance and, in doing so, demonstrate possible benefits over the traditional fluoroscopic technique. METHODS: Using a standard CT scanner, patients are placed supine with head in extension. Barium paste and a CT scout image are used to identify and plan a trajectory to the foramen ovale. A laser localization system built into the CT scanner helps to guide placement of the spinal needle into the foramen ovale. The needle position in the foramen is confirmed with a short-sequence CT scan. RESULTS: CT-guided PGR provides multiple benefits over standard fluoroscopy, including improved visualization of the skull base and significant reduction in radiation exposure to the surgeon and staff. Side benefits include improved procedure efficiency, definitive imaging evidence of correct needle placement, and potentially increased patient safety. We have had no significant complications in over 200 patients. CONCLUSION: CT-guided PGR is a useful technique for treating trigeminal neuralgia based on better imaging of the skull base, better efficiency of the procedure, and elimination of radiation exposure for the surgeon and staff compared to traditional fluoroscopic based techniques.