TY - JOUR
T1 - Rapid Eye Movements in Myasthenia Gravis
T2 - II. Electro-oculographic Analysis
AU - Yee, Robert D.
AU - Cogan, David G.
AU - Zee, David S.
AU - Baloh, Robert W.
AU - Honrubia, Vicente
PY - 1976/9
Y1 - 1976/9
N2 - Voluntary saccades were studied by electro-oculography in ten patients with myasthenia gravis (MG) and in eight patients with other types of ophthalmoplegia. Despite limited range of eye movements, maximum velocities of 20° and 40° saccades in patients with MG were not significantly different from those in normal individuals, whereas maximum velocities in patients with other types of ophthalmoplegia were significantly decreased. In some myasthenic patients, small amplitude saccades were hypermetric and had high velocities, appearing clinically as “quiver” movements characteristic of MG. In MG the preservation of saccades with high initial velocities, even in the presence of severe ophthalmoplegia, suggests that muscle fibers generating rapid movements during saccades (twitch fibers) can be relatively spared when muscle fibers responsible for maintenance of excentric gaze (tonic fibers) are severely affected.
AB - Voluntary saccades were studied by electro-oculography in ten patients with myasthenia gravis (MG) and in eight patients with other types of ophthalmoplegia. Despite limited range of eye movements, maximum velocities of 20° and 40° saccades in patients with MG were not significantly different from those in normal individuals, whereas maximum velocities in patients with other types of ophthalmoplegia were significantly decreased. In some myasthenic patients, small amplitude saccades were hypermetric and had high velocities, appearing clinically as “quiver” movements characteristic of MG. In MG the preservation of saccades with high initial velocities, even in the presence of severe ophthalmoplegia, suggests that muscle fibers generating rapid movements during saccades (twitch fibers) can be relatively spared when muscle fibers responsible for maintenance of excentric gaze (tonic fibers) are severely affected.
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U2 - 10.1001/archopht.1976.03910040299001
DO - 10.1001/archopht.1976.03910040299001
M3 - Article
C2 - 962656
AN - SCOPUS:0016997412
SN - 0003-9950
VL - 94
SP - 1465
EP - 1472
JO - Archives of ophthalmology
JF - Archives of ophthalmology
IS - 9
ER -