Hee Kyung Yang1, Jae Hyoung Kim2, Jeong-Min Hwang1. 1. Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea (Republic of). 2. Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea (Republic of).
Abstract
PURPOSE: To elucidate the imaging findings of congenital oculomotor nerve palsy by evaluating the oculomotor nerve and extraocular muscles on magnetic resonance (MR) imaging in a relatively large series of 14 patients with congenital oculomotor nerve palsy. METHODS: Ophthalmologic examination of 14 consecutive patients diagnosed with congenital oculomotor nerve palsy, and MR imaging of the orbit and oculomotor nerves were performed. RESULTS: Of the 14 patients with congenital oculomotor nerve palsy, 13 patients (93%) were unilateral and 12 patients (86%) had incomplete palsy. On MR imaging, 5 patients (36%) had hypoplasia or aplasia of the oculomotor nerve with variable degrees of extraocular muscle atrophy on the affected side. Of the 14 patients, nine (64%) had normal-sized oculomotor nerves with or without muscle atrophy. The most frequently involved muscles were the inferior rectus (64%) and medial rectus (50%), followed by the superior rectus (29%) and inferior oblique muscles (14%). None of the 14 patients showed an abnormal abducens nerve. CONCLUSION: Congenital oculomotor nerve palsy was mostly incomplete and hypoplasia or aplasia of the oculomotor nerve was apparent in one third of patients showing variable degrees of extraocular muscle atrophy, mostly of the medial rectus and inferior rectus muscles.
PURPOSE: To elucidate the imaging findings of congenital oculomotor nerve palsy by evaluating the oculomotor nerve and extraocular muscles on magnetic resonance (MR) imaging in a relatively large series of 14 patients with congenital oculomotor nerve palsy. METHODS: Ophthalmologic examination of 14 consecutive patients diagnosed with congenital oculomotor nerve palsy, and MR imaging of the orbit and oculomotor nerves were performed. RESULTS: Of the 14 patients with congenital oculomotor nerve palsy, 13 patients (93%) were unilateral and 12 patients (86%) had incomplete palsy. On MR imaging, 5 patients (36%) had hypoplasia or aplasia of the oculomotor nerve with variable degrees of extraocular muscle atrophy on the affected side. Of the 14 patients, nine (64%) had normal-sized oculomotor nerves with or without muscle atrophy. The most frequently involved muscles were the inferior rectus (64%) and medial rectus (50%), followed by the superior rectus (29%) and inferior oblique muscles (14%). None of the 14 patients showed an abnormal abducens nerve. CONCLUSION:Congenital oculomotor nerve palsy was mostly incomplete and hypoplasia or aplasia of the oculomotor nerve was apparent in one third of patients showing variable degrees of extraocular muscle atrophy, mostly of the medial rectus and inferior rectus muscles.