Intraparenchimal mesencephalic cyst: an unusual location.

Objective: Intraparenchimal mesencephalic cyst which occurs in lateral part of the mesencephalon is very unusual. In addition to describe this case, the authors also review other brainstem cysts described in literature and briefly discus concept of their origin.

Methods: We report a patients with cyst in right part of the mesencephalon of a 10-years old girl presenting symptoms of increased intracranial pressure and local compression. We discuss the clinical presentation, radiological investignation, pathological features and surgical treatment options for this lesion.

Discussion: First surgical intervention was fenestration cysts, second ventricular-peritoneal shunt and third stereotactic navigation cysto-cysternostomo mesencephalic cyst with ponotocerebelar subarachnoidal space. Biochemical examination showed fluid in cyst and patohistological examination showed fibrilar connective tissue without epithelial cell of the wall cysts.

Conclusion: Eight years later she is in good condition. Surgical resection or total extirpation cyst like that is not recommended.