[Analysis of 138 cases of superior oblique muscle paralysis]

Congenital or early infantile paralysis of the superior oblique muscle is primarily caused by congenital anomaly of the ocular muscles or by birth trauma, while the acquired is mostly caused by trauma, influenza, or acute infection. The diagnosis is done by Lancaster's test, the synoptophore, and the cover test in combination with prisms. For incooperative children, Park's three step test may be used. The angle of strabismus can be measured with the cover test and prisms, or by the synoptophore. For treatment, the patients were divided into (1) the group of prism correction, (2) the group of inferior oblique attenuation in the same eye, (3) the group of inferior rectus attenuation in the other eye, (4) the group of inferior oblique attenuation in the same eye combined with inferior rectus attenuation in the other eye, and (5) the group of superior oblique paralysis complicated with horizontal heterotropia. The immediate and longterm curative effect had been satisfactory. It is important to differentiate congenital cases from the acquired, the primary torticollis from that of ophthalmic origin, and the paralysis of superior oblique in one eye from the paralysis of the superior rectus in the other eye.