H M Elflein1, F Thömke, W Müller-Forell, S Pitz. 1. Department of Ophthalmology, University Medicine Centre, Johannes Gutenberg - University, Mainz, Germany. elflein@augen.klinik.uni-mainz.de
Abstract
PURPOSE: To describe clinical features and management of 4 patients suffering from unilateral superior oblique palsies due to MRI-documented trochlear nerve schwannomas. METHODS: Chart reviews of 4 patients seen at the departments of ophthalmogy and neurology at the University of Mainz. RESULTS: All four patients were male, aged 36 to 72 years at initial presentation. None suffered from neurofibromatosis. The history of double vision prior presentation was 9 months to 13 years, follow-up time was 9 to 156 months. Two patients didn't receive any intervention: one remained stable over the follow-up time of 9 months. In patient #2, fourth nerve palsy was diagnosed 13 years prior to confirmation of a trochlear schwannoma by high-resolution MRI. In the third patient disturbing diplopia and head tilt were sufficiently corrected by strabismus surgery (combined oblique muscle surgery). The fourth patient had received stereotactic radiotherapy of an 8 mm schwannoma. He remained unchanged in the orthoptic measurements for 3,5 years. None of these patients developed any additional symptoms or signs of further cranial nerve or central nervous system involvement. CONCLUSION: A trochlear nerve schwannoma is a possible cause of an isolated unilateral superior oblique palsy. MRI is a helpful tool for diagnosis and follow-up. Conservative management seems to be justified as patients can remain unchanged over years.
PURPOSE: To describe clinical features and management of 4 patients suffering from unilateral superior oblique palsies due to MRI-documented trochlear nerve schwannomas. METHODS: Chart reviews of 4 patients seen at the departments of ophthalmogy and neurology at the University of Mainz. RESULTS: All four patients were male, aged 36 to 72 years at initial presentation. None suffered from neurofibromatosis. The history of double vision prior presentation was 9 months to 13 years, follow-up time was 9 to 156 months. Two patients didn't receive any intervention: one remained stable over the follow-up time of 9 months. In patient #2, fourth nerve palsy was diagnosed 13 years prior to confirmation of a trochlear schwannoma by high-resolution MRI. In the third patient disturbing diplopia and head tilt were sufficiently corrected by strabismus surgery (combined oblique muscle surgery). The fourth patient had received stereotactic radiotherapy of an 8 mm schwannoma. He remained unchanged in the orthoptic measurements for 3,5 years. None of these patients developed any additional symptoms or signs of further cranial nerve or central nervous system involvement. CONCLUSION: A trochlear nerve schwannoma is a possible cause of an isolated unilateral superior oblique palsy. MRI is a helpful tool for diagnosis and follow-up. Conservative management seems to be justified as patients can remain unchanged over years.