Outcomes after microvascular decompression for patients with trigeminal neuralgia and suspected multiple sclerosis

Microvascular decompression (MVD) is an established surgical therapy for patients with idiopathic trigeminal neuralgia (TN). The role of MVD in patients with definite or suspected multiple sclerosis (MS) remains controversial.

During the period 2000-2012, 10 patients with medically refractory TN and ipsilateral brainstem T2 hyperintensity underwent MVD. In 5 patients, additional clinical features suspicious for MS were present, including prior optic neuritis (n = 2), multiple disseminated lesions (n = 3), and elevated immunoglobulin G index (n = 2). One patient had failed prior percutaneous surgery; 1 patient had Burchiel type 2 TN. Follow-up (median, 14 months) was censored at the time of additional surgery (n = 6) or last clinic visit (n = 4).

Neurovascular compression was confirmed at surgery from the superior cerebellar artery (SCA) plus adjacent vein (n = 4), vein alone (n = 3), SCA alone (n = 2), and SCA plus anterior inferior cerebellar artery (n = 1). Initially after MVD, 8 patients (80%) were pain-free and subsequently tapered off medications for their facial pain. Pain recurred in 6 patients at a median of 4 months (range, 1-23 months). Actuarial rates of being pain-free off medications were 50% at 3 months and 15% at 2 years. In 6 patients, additional treatments were performed, including glycerol rhizotomy (n = 4), radiosurgery (n = 2), balloon compression (n = 2), and repeat MVD (n = 1). At last contact, 5 of the 6 patients who were retreated were pain-free.

Facial pain outcomes after MVD in patients with suspected MS-related TN are poor compared with outcomes for patients with idiopathic TN. This study provides further support that many patients with MS-related TN have pain that is centrally mediated, reducing the effectiveness of procedures performed on the trigeminal root, ganglion, or divisions.