Trigeminal Nerve-Blood Vessel Relationship as Revealed by High-resolution Magnetic Resonance Imaging and Its Effect on Pain Relief after Gamma Knife Radiosurgery for Trigeminal Neuralgia.
OBJECTIVE
Blood vessel (BV) compression of the trigeminal nerve (Cranial Nerve [CN] V) is a common cause of trigeminal neuralgia (TN). High-resolution magnetic resonance imaging scans obtained during gamma knife radiosurgery (GKRS) in patients with TN may be used to analyze the BV-CN V relationship. Follow-up data from a large series of patients treated with GKRS for TN were used to provide information regarding the BV-CN V relationship and pain relief.


METHODS
T1-weighted, axial 1-mm-thick volume acquisition magnetic resonance imaging scans were obtained through the area of CN V at its exit from the brainstem after injection of 15 ml of gadolinium. The BV-CN V relationship on the symptomatic side that was treated with GKRS was categorized into the following groups: Group 1 (no close relationship), Group 2 (BV close to CN V but not touching it), and Groups 3 and higher (BV-CN V contact).


RESULTS
A total of 181 symptomatic nerves were studied in 179 patients with TN who were treated with GKRS. In BV-CN V Groups 1, 2, and 3 and higher, respectively, were 43 sides (24%), 31 sides (17%), and 107 sides (59%). In 100 sides where there was no surgical procedure before GKRS, 50% or greater pain relief was more likely in those with BV-CN V contact (51 [88%] of 58 sides) than in those without BV-CN V (29 [69%] of 42 sides) (P = 0.024). BV-CN V contact was observed more often in men (55 [69%] of 80 sides) than in women (52 [52%] of 101 sides) (P = 0.023) and more often in patients who had unilateral TN (104 [62%] of 169 patients) rather than bilateral TN (2 [20%] of 10 patients) (P = 0.016).


CONCLUSIONS
In patients who have not undergone previous surgery for TN, BV-CN V contact revealed by high-resolution magnetic resonance imaging may indicate a particularly favorable response to GKRS.
Brisman
Ronald
R
Department of Neurological Surgery, College of Physicians and Surgeons, Columbia University, New York Presbyterian Hospital, Columbia Presbyterian Medical Center, New York, New York 10032-2699, USA. rb36@columbia.edu
Khandji
Alexander G
AG
Mooij
Robertus B M
RB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001808:Blood Vessels / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000175:diagnosis; D010146:Pain / Q000503:physiopathology*; D010166:Palliative Care; D016634:Radiosurgery / Q000009:adverse effects; D012727:Sex Characteristics; D016019:Survival Analysis; D016896:Treatment Outcome; D014276:Trigeminal Nerve / Q000473:pathology*; D014277:Trigeminal Neuralgia / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*