Related Experiment Video
Updated: Mar 22, 2026

Full-Circle Cauterization of Limbal Vascular Plexus for Surgically Induced Glaucoma in Rodents
Published on: February 15, 2022
Chronic Progressive External Ophthalmoplegia in the Absence of Ptosis
Robert C Bucelli1, Michael S Lee, Collin M McClelland
1Department of Neurology (RB), Washington University School of Medicine, St. Louis, Missouri; and Departments of Ophthalmology and Visual Neurosciences (ML, CMM), Neurology (ML), and Neurosurgery (ML), University of Minnesota, Minneapolis, Minnesota.
Abstract:
Classically defined as bilateral, symmetric, and progressive ophthalmoparesis with myopathic ptosis, chronic progressive external ophthalmoplegia (CPEO) rarely has been reported in the absence of ptosis. We describe 2 patients with CPEO and without ptosis who presented with binocular diplopia related to small-angle esodeviations, poor fusional amplitudes, and slow saccades. In both cases, hematological studies and neuroimaging ruled out alternative etiologies, whereas muscle biopsy showed findings of mitochondrial myopathy.
Related Concept Videos
Accessory Structures of the Eye
Glaucoma: Overview
Open Angle Glaucoma: Treatment
Drugs such as carbonic anhydrase inhibitors, α2- and...
Angle Closure Glaucoma: Treatment
Photoreceptors and Visual Pathways
Muscles of the Eye
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and...

