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Updated: May 28, 2026

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System
Published on: May 12, 2011
Accessory eye muscle in a young boy with external ophthalmoplegia
1Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany. andrej.krasny@googlemail.com
Abstract:
A seven-year-old boy presented to the neuropediatric clinic with right-sided ptosis, external ophthalmoplegia, and mental retardation. Orbital magnetic resonance imaging (MRI) revealed anomalous soft tissue within the intraconal region, which was interpreted as an atavistic retractor bulbi muscle. In patients with external ophthalmoplegia and ptosis, anatomic variations observed in MRI should be given due consideration. In fact, knowledge about rare anatomical anomalies may contribute to a more accurate diagnosis of such ocular symptoms.
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