Purpose: Ophthalmoplegia (OP) can have numerous etiologies and different clinical presentations. Most causes of OP can be narrowed down to specific anatomical locations based on clinical information. The aim of this study was to outline the different categories of diseases encountered in patients with OP, based on the location along the ocular motor pathways, and the most appropriate imaging modality for the given scenarios.
Methods: Representative neuroimaging examples of pathological processes causing OP are displayed, sequenced by anatomical location and disease category. Correlations between the clinical presentation and site of pathology with imaging protocol recommendations are also presented.
Results: Diseases affecting ocular movement can be divided into categories including: injuries or diseases of the cerebral hemispheres, midbrain, pons, and cerebellum, ocular motor nerve palsies, intrinsic extraocular muscle diseases and orbital diseases secondarily affecting the extraocular muscles. The cranial nerves responsible for ocular movements can be affected intrinsically or extrinsically along their nuclei, their course in the brainstem, in the cisterns, skull base, cavernous sinuses and orbits. The extraocular muscles can be affected primarily or secondarily by adjacent pathological processes in the orbit. Clinical information can help narrow down the differential diagnoses in terms of anatomical site of involvement and prompt the most appropriate neuroimaging techniques.
Conclusion: By understanding the pathophysiology of OP the neuroradiologist can discuss clinical cases with the referring clinician and determine a timely, accurate method of imaging to achieve the most precise differential diagnosis.
Keywords: Computed tomography; Cranial nerves; Magnetic resonance imaging; Oculomotor nerve palsy; Ophthalmoplegia.