25-year Experience with 1600 Patients
Kanpolat Y, Savas
A, Bekar A, et al
Trigeminal neuralgia is characterized by brief bouts of severe, sharp, shock-like pain localized to the somatosensory distribution of the trigeminal nerve. Although agents, such as carbamazepine, phenytoin and clonazepam, may be effective in some cases, surgical procedures have provided additional options for patients refractory to medical therapy. Kanpolat and colleagues performed a retrospective analysis of data from 1600 patients with idiopathic trigeminal neuralgia (ITN) who underwent percutaneous controlled radiofrequency trigeminal rhizotomy (RF-TR) to determine the effectiveness of the procedure.
From 1974 to 1999, 1724 patients underwent 2310 RF-TR procedures at the Department of Neurosurgery, Ankara University, Ankara Turkey. Of the 1724 patients, 1600 were cases of ITN, and among these, 2138 percutaneous radiofrequency rhizotomy procedures were performed. The ITN group included 834 (52.1%) women and 766 (47.9%) men. The mean age was 56.83 +/- 13 years (range, 15 to 99 years). Bilateral idiopathic trigeminal neuralgia was discovered in 67 patients and 36 were treated with bilateral RF-TR. The majority of the patients (n = 421) had trigeminal neuralgia for less than 24 months, whereas 36 had trigeminal neuralgia for more than 20 years (mean, 6.5 years). The RF-TR needle was inserted toward the temporal fossa. The desired target was the preganglionic fibers of the gasserian ganglion. Thermistor electrodes were used to make lesions at temperatures of 55-70°C (131-158°F). In total, 1216 (76%) patients were successfully managed with a single treatment whereas 384 (24%) required multiple RF-TR procedures. The average follow-up time was 68.1 +/- 66.4 months (range, 12-300 months).
A total of 1561 (97.6%) patients experienced acute pain relief after the RF-TR procedure; 123 (7.7%) patients noted early pain recurrence (within less than 6 months) and 278 (17.4%) patients experienced late recurrence (after 6 or more months). In 719 (44.9%) patients followed for 5 years, 57.7% achieved complete pain control after a single RF-TR procedure; with multiple RF-TR procedures, 92% of patients experienced pain relief. At 10-year follow-up, 52.3% reported pain relief after undergoing a single RF-TR procedure compared with 41% at the 20-year follow-up. The complications included diminished corneal reflex in 91 (5.7%) patients, masseter weakness and paralysis in 66 (4.1%), dysesthesia in 16 (1%), anesthesia dolorosa in 12 (0.8%), keratitis in 10 (0.6%), and transient paralysis of cranial nerves III and VI in 12 (0.8%). Permanent cranial nerve VI palsy was noted in 2 patients, cerebrospinal fluid leakage in 2, carotid-cavernous fistula in 1, and aseptic meningitis in 1 patient. The investigators concluded that RF-TR is an effective, minimally invasive procedure that may be especially indicated in older patients with ITN confined to the second and third branches. The treatment can be repeated safely if the pain recurs.