Herpes Simplex Reactivation After Surgical Treatment of Trigeminal Neuralgia: A Retrospective Cohort Study

Background: Herpes simplex virus (HSV) reactivation after surgery for trigeminal neuralgia has long been recognized. Only a few studies to date have focused on this complication, and its actual incidence remains unknown. The aim of this study was to investigate the incidence of postoperative herpes labialis (HL) in a cohort of patients treated with either percutaneous balloon compression or microvascular decompression to identify potentially significant differences between different treatments. Methods: A total of 92 patients who were operated on for TN with microvascular decompression (group A) or percutaneous balloon compression (group B) in the period 2010-2017 were retrospectively evaluated. The 2 subgroups of patients were compared according to history of previous HL and incidence of postoperative HL. Results: The final cohort comprised 56 male and 36 female patients. Average age was 58.50 years; 30 male patients belonged to group A and 26 male patients belonged to group B. Lifetime incidence of episodes of HL before surgery in 18/58 patients in group A (31.0%) and 12/34 patients in group B (35.3%), with no statistically significant difference among subgroups. Postoperatively, 1/56 patients in group A (1.7%) experienced HL compared 5/34 patients in group B (14.7%), with a strongly statistically significant difference between the 2 subgroups. Conclusions: In our clinical experience, herpes simplex virus reactivation after surgery for trigeminal neuralgia is not so rare and is still not completely understood. Postoperative herpes simplex virus reactivation could be due to a direct mechanical injury on gasserian ganglion neurons, which is more common after percutaneous balloon compression.