Role of magnetic resonance imaging in heavy eye syndrome

PurposeThe aim of this study is to assess the importance of magnetic resonance imaging (MRI) before surgery in highly myopic patients, evaluating the capability of imaging to identify muscles displacement and orbital pulley abnormalities and their role in the pathogenesis of heavy eye syndrome (HES).MethodsWe reviewed the medical records and high-resolution orbital MRIs of highly myopic adults with HES, who underwent surgery for strabismus at the Sant'Orsola-Malpighi University Hospital of Bologna from January 2007 to June 2016. The measure of the angle of dislocation between lateral rectus and superior rectus and lateral rectus-superior rectus band (LR-SR band) were evaluated on coronal MRI imaging.ResultsA total of 54 patients with HES were evaluated by MRI. Mean axial length was 30.5±3 mm. Mean distance esotropia was 49.2±14.4 prism diopters (PD) and the mean hypotropia was 4.3±4.4 PD. All subjects exhibited severe superotemporal globe prolapse that displaced the lateral rectus inferiorly and the superior rectus muscle medially with mean angle of dislocation of 167.5±12.9° on MRI. The LR-SR band was thinned in 56 eyes, ruptured in 8 and not evaluable in 1 case.ConclusionsIn our study, we detected muscles displacement in all subjects and we discovered alteration of the LR-SR band in patients with HES, suggesting a possible role in the pathogenesis of this disease. The evaluation of preoperative orbital MRI imaging in patients with highly myopic strabismus is helpful to detect different anatomical etiology and eventually to drive the choice of appropriate surgery.