Stereotactic radiation is an effective, long-term treatment for trigeminal neuralgia, a painful condition that often accompanies multiple sclerosis, according to a study that will be presented Oct. 31 at the Annual Meeting of the American Society for Radiation Oncology (ASTRO).
Trigeminal neuralgia is an extremely painful condition caused by the dysfunction of the trigeminal nerve, which is responsible for sensation in the face. Gamma Knife (Elekta) stereotactic radiosurgery uses focused radiation beams to target well-defined areas and is typically applied to brain tumors, but previous studies have demonstrated short-term relief in treating trigeminal neuralgia with the technique.
The researchers indicated that Gamma Knife radiosurgery offers the advantage of high accuracy in delivering radiation to nerve roots, while sparing surrounding tissue and therefore reducing side effects.
The study assessed long-term treatment effects of radiosurgery on 13 patients (14 nerves) with a mean follow-up time of 36 months. The researchers measured Barrow Neurological Institute (BNI) scores before and after radiosurgery, with 93 percent of patients presenting with BNI IV scores before treatment.
More than 57 percent of patients experienced relief and lower BNI scores after the radiotherapy. The median onset of pain relief occurred at one week. Post-radiosurgery BNI scores measured 57 percent at BNI I; 7 percent at BNI III; and 36 percent at BNI IV.
The median relief for patients who responded positively to Gamma Knife radiosurgery was 36 months, while six patients were able to discontinue their trigeminal neuralgia medications. No major complications from the radiotherapy were observed, although two patients reported transient or moderate facial numbness.
"Our study shows that radiosurgery using Gamma Knife is a proven alternative to surgery or anti-epileptic drugs," stated lead author Tejan Diwanji of the University of Maryland School of Medicine in Baltimore.