Paresis of the Oculomotor Nerve due to Neurovascular Conflict with Superior Cerebellar Artery

Abstract

Background Neurovascular conflict between the oculomotor nerve and a posterior circulation cerebral artery is a relatively frequent radiologic finding; however, it manifests minimally clinically (by slower photoreaction on the ipsilateral side). Sustained paresis of the oculomotor nerve that arose directly due to neurovascular conflict between the superior cerebral artery (SCA) and the oculomotor nerve, and resolved after microvascular decompression, is extremely rare and has not yet been published.

Methods A 34-year-old female patient presented with an advancing ptosis and downward gaze on one side. Differential diagnostics ruled out all other causes of the oculomotor paresis. Magnetic resonance imaging showed significant compression of the oculomotor nerve by an aberrant SCA on the ipsilateral side. Neurovascular decompression performed microsurgically resulted in near complete resolution of the symptoms.

Results This case report aims to present a case of a rare clinical condition caused by a generally common anatomical variation. This variation proved to be the only cause of the patient's symptoms, which resolved after microsurgical restoration of the neuroanatomy.

Conclusions Oculomotor nerve paresis caused directly by neurovascular conflict is an extremely rare diagnosis. Microvascular decompression should be considered in these cases, if other causes have been excluded.

Keywords

anatomical anomaly - neurovascular conflict - oculomotor nerve paresis - microvascular decompression

Informed Consent and Patient Details

Informed consent was obtained in accordance with the local authority.

Authors' Contribution

Mat.K. and M.S. were involved in writing the original draft and developing the methodology. All the authors were involved in writing, review, and editing of the manuscript and formal analysis. Visualization was done by Mat.K. and A.Š. Data curation was done by Mat.K. and Mar.K. Conceptualization was done by Mat.K., A.Š., and Mar.K. Supervision of the study was done by M.S. All the authors have read and agreed to the published version of the manuscript.

Publikationsverlauf

Eingereicht: 17. Juni 2024

Angenommen: 17. September 2024

Accepted Manuscript online:
19. September 2024

Artikel online veröffentlicht:
21. November 2024

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