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Endoscopic Third Ventriculostomy and Pineal Biopsy from a Single Entry Point
Published on: June 28, 2024
Dorsal midbrain syndrome secondary to a pineocytoma
1Dakota Vision, Rapid City, South Dakota, USA. allmerd@aol.com
Background:
Dorsal midbrain syndrome is a triad of signs consisting of vertical gaze palsy, light-near dissociation of the pupils, and convergence retraction nystagmus. Associated findings may also be present. The most-common etiologies are pineal gland tumors and midbrain infarction. Pineal gland tumors are rare tumors that show a predilection for males. The specific tumor reported herein, a pineocytoma, shows no gender predilection and is most common in mid- to late adulthood.
Case Report:
A 38-year-old Native American man came to us with signs and symptoms consistent with dorsal midbrain syndrome. A neurological evaluation revealed the presence of a pineocytoma, which was later excised unsuccessfully. An explanation of the findings associated with dorsal midbrain syndrome is provided.
Conclusion:
Patients who demonstrate signs consistent with dorsal midbrain syndrome should be referred for a neurological evaluation--including an MRI--to rule out any midbrain lesion.
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