Efficacy of internal neurolysis for older patients suffering from trigeminal neuralgia without neurovascular compression

Background: The efficacy of internal neurolysis (IN) for older patients with trigeminal neuralgia (TN) without neurovascular compression remains unclear. We evaluated the clinical outcomes of IN in older patients with TN without neurovascular compression, comparing them with those of their younger counterparts. Methods: We retrospectively reviewed 22 patients with TN who underwent IN without neurovascular compression. They were divided into older (≥70 years, n = 11) and younger (<70 years, n = 11) groups. Clinical variables included pain type (typical vs. atypical), recurrence status, and intraoperative neurophysiological findings. Surgical outcomes were assessed using the Barrow Neurological Institute (BNI) pain scale, with favorable outcomes defined as BNI I–II. Results: The older group had a higher proportion of typical TN cases (9/11 [81.8%]), whereas atypical facial pain was more frequent in the younger group (6/11 [54.5%]). Favorable outcomes were achieved in 19/22 patients overall (86.4%) (9/11 [81.8%] older and 10/11 [90.9%] younger patients). When stratified by pain type, older patients with typical TN achieved favorable outcomes in 8/9 cases (88.9%), whereas older patients with atypical pain showed favorable outcomes in 1/2 cases (50.0%). In the younger group, favorable outcomes were observed in those with typical TN (5/5 [100%]) and in 5/6 patients with atypical facial pain (83.3%). Poor outcomes (BNI III) occurred in three patients (13.6%) (two older and one younger patient). Transient facial numbness was observed in three patients, including two younger patients (18.2%) and one older patient (9.1%), all of which resolved during the follow-up. Intraoperative neurophysiological monitoring demonstrated shortening of latency and/or increased amplitude in most of the patients who experienced favorable outcomes. Conclusions: IN achieved favorable pain control in 86.4% of those with TN without neurovascular compression. Older patients experienced outcomes comparable to those of younger ones, particularly for typical TN. IN likely represents an effective surgical option for this patient group, even in the absence of a responsible vessel.