Orthoptic and video‐oculographic analyses in oculopharyngeal muscular dystrophy

Mild ophthalmoparesis can be seen in oculopharyngeal muscular dystrophy (OPMD). Methods: Orthoptic analysis included assessment of phoria/tropia, eye excursion, saccades, pursuit, stereoacuity, and Hess–Lancaster screen test. Video‐oculography included fixation, horizontal and vertical saccades, and pursuit. Results: Orthoptic abnormalities were: tropia (4 of 6); abnormal eye excursion (4 of 6, 78% involved lateral or superior rectus muscles); abnormal horizontal or vertical saccades (2 of 6); abnormal pursuit (0 of 6); abnormal stereoacuity (2 of 6); and pathological Hess–Lancaster screen (4 of 6). Video‐oculographic abnormalities were present for: fixation (1 of 6); saccade latency (1 of 6); horizontal pursuit (3 of 6); and vertical pursuit (0 of 6). For horizontal saccades, mean velocity, peak velocity, and gain were pathological in 5 of 6, 5 of 6 (61% of pathological mean and peak velocities involved abducting eye movements), and 3 of 6, respectively. For vertical saccades, mean velocity, peak velocity, and gain were pathological in 4 of 6, 4 of 6 (53% involved upward movements), and 3 of 6, respectively. Conclusion : The data indicate preferential involvement of lateral and (to a lesser degree) superior rectus muscles in OPMD. Muscle Nerve 52: 554–558, 2015