Does increased nerve length within the treatment volume improve trigeminal neuralgia radiosurgery? A prospective double-blind, randomized study.
OBJECTIVE
To test the hypothesis that increasing the nerve length within the treatment volume for trigeminal neuralgia radiosurgery would improve pain relief.


METHODS
Eighty-seven patients with typical trigeminal neuralgia were randomized to undergo retrogasserian gamma knife radiosurgery (75 Gy maximal dose with 4-mm diameter collimators) using either one (n = 44) or two (n = 43) isocenters. The median follow-up was 26 months (range 1-36).


RESULTS
Pain relief was complete in 57 patients (45 without medication and 12 with low-dose medication), partial in 15, and minimal in another 15 patients. The actuarial rate of obtaining complete pain relief (with or without medication) was 67.7% +/- 5.1%. The pain relief was identical for one- and two-isocenter radiosurgery. Pain relapsed in 30 of 72 responding patients. Facial numbness and mild and severe paresthesias developed in 8, 5, and 1 two-isocenter patients vs. 3, 4, and 0 one-isocenter patients, respectively (p = 0.23). Improved pain relief correlated with younger age (p = 0.025) and fewer prior procedures (p = 0.039) and complications (numbness or paresthesias) correlated with the nerve length irradiated (p = 0.018).


CONCLUSIONS
Increasing the treatment volume to include a longer nerve length for trigeminal neuralgia radiosurgery does not significantly improve pain relief but may increase complications.
Flickinger
J C
JC
Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA. jflickin@msx.upmc.edu
Pollock
B E
BE
Kondziolka
D
D
Phuong
L K
LK
Foote
R L
RL
Stafford
S L
SL
Lunsford
L D
LD
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016634:Radiosurgery / Q000379:methods*; D014276:Trigeminal Nerve / Q000473:pathology / Q000601:surgery*; D014277:Trigeminal Neuralgia / Q000473:pathology / Q000601:surgery*