The efficacy and safety of nerve loop blocking in the treatment of blepharospasm in Meige syndrome

Abstract

Objective: To evaluate the efficacy and safety of nerve loop blocking in the treatment of blepharospasm caused by Meige syndrome. Methods: It was a retrospective case series study. Patients with Meige syndrome characterized by blepharospasm or blepharospasm-oromandibular dystonia who underwent nerve loop blocking in the Ophthalmology Department of Henan No. 3 Provincial People's Hospital from April 2018 to January 2020 were included. Before and after surgery, blepharospasm was graded, and the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was used to score the symptoms of ocular and oral dystonia. The improvement rate of ocular spasm was calculated after surgery according to the scores. The postoperative complications were observed. The Wilcoxon rank test was used to compare the BFMDRS movement subscale scores before and after surgery. The independent sample Mann-Whitney U test was used to compare the improvement rates of eye spasm between male and female patients and between patients with and without combined oromandibular dystonia. Results: Among the 199 patients included, 64 (32.2%) were males, and 135 (67.8%) were females, aged 58 (51, 64) years (22-79 years). The postoperative follow-up period was 24 (21, 28) months. Preoperatively, blepharospasm was graded as grade 3 in 12 patients (6.0%) and grade 4 in 187 patients (94.0%), while the postoperative blepharospasm grades were grade 0 in 100 patients (50.3%), grade 1 in 64 patients (32.2%), grade 2 in 31 patients (15.6%), and grade 3 in 4 patients (2.0%). There was statistically significant difference in the BFMDRS scores of ocular dystonia before and after surgery [8.0 (8.0, 8.0) vs. 0.0 (0.0, 1.0); Z=-12.41, P<0.001]. The improvement rate of blepharospasm in all patients was 100% (87.5%, 100%), ranging from 43.8% to 100%, with no statistically significant difference between patients of different genders and between patients with and without combined oral dystonia (both P>0.05). Statistically significant difference existed in the scores of oral dystonia before and after surgery [2.0 (0.5, 4.5) vs. 1.0 (0.5, 2.0); Z=-4.38, P<0.001], with 25 of 65 patients (38.5%) having their oral symptoms improved. Postoperative complications included eyelid valgus (7.5%, 15/199), frontal numbness (100%, 199/199) and tearing (89.9%, 179/199). Conclusion: Nerve loop blocking is a relatively safe and effective method in the treatment of blepharospasm symptoms of Meige syndrome.