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
