Orbital magnetic resonance imaging is useful in age-related distance esotropia.

PURPOSE To describe findings for orbital magnetic resonance imaging (MRI) in patients with age-related distance esotropia (ARDE). METHODS We compared 31 orbital MRI from patients with ARDE (77±7 SD years) with 2 control groups: 32 orbits from individuals aged 18-50 years (33±8 SD years) and 16 orbits from individuals aged >60 years (77±7 SD years). MRI scans were acquired using 3D fast field echo in T1 sequence without fat saturation. Exclusion criteria for all groups were neurological or thyroid disease and a relevant ophthalmological history (e.g., high myopia, diplopia from another etiology, complicated cataract surgery, etc.). Muscle displacement and characteristics of the lateral rectus-superior rectus (LR-SR) intermuscular band were analyzed. RESULTS The analysis of the muscles and angles revealed a series of statistically significant differences (p<0.07) between the groups. Subjects with ARDE had LR pulley positions 1.32±0.19mm lower than in younger controls, and the medial rectus (MR) pulley positions were 0.68±0.19mm lower than in younger. Older controls had LR and MR pulley positions 0.85±0.20mm and 0.49±0.23mm lower than in younger. ARDE subjects had LR pulley positions 0.46±0.26mm lower than in older control group. The LR-SR band was absent in 35.5% of ARDE patients and in 12.5% of older control group (p=0.168). CONCLUSIONS MRI showed that displacements of LR and LR-SR band degeneration could facilitate the diagnosis of patients with ARDE.