편측 상사근마비에서 자기공명영상으로 측정한 상사근 단면적과 임상양상과의 연관성

Abstract

Purpose To investigate the correlation of superior oblique (SO) atrophy of magnetic resonance imaging (MRI) with clinical features including surgical success in unilateral SO palsy. Methods This study was a retrospective review of the records of 38 patients who had undergone inferior oblique (IO) myectomy due to SO palsy between January 2017 and March 2019 at our hospital. The patients with more than a 40% decrease of cross-section areas using preoperative orbital MRI were categorized into the atrophic group (16 patients). We compared surgical outcomes between the atrophic and non-atrophic groups. Results Preoperative IO over-action and vertical deviation showed no significant difference, but the excyclotorsion in paralytic eyes were more frequent in the atrophic group and the surgical success (62.5% vs. 95.5%), and the degree in improvement of vertical deviation (7.17 ± 5.19 prism diopters [PD] vs. 11.05 ± 5.59 PD) was significantly lower in the atrophic group. The degree of SO atrophy showed a weak correlation with the degree of improvement of hypertropia or diopter differences of bilateral head tilting. Conclusions SO atrophy, detected using preoperative MRI of unilateral SO palsy patients did not show a definite correlation with clinical features except for excyclotorsion in paralytic eyes but did show a clinically significant correlation with surgical outcomes. Preoperative MRI can therefore be used for predicting surgical outcomes of IO myectomy in unilateral SO palsy patients.