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Application of endoscopy for a midbrain tumor.

OBJECTIVE AND IMPORTANCE
It has been difficult to obtain a biopsy of a midbrain lesion. In addition, proper cerebrospinal fluid diversion should be secured because progressing tumor in the midbrain causes obstructive hydrocephalus. We report on the superiority of flexible neuroendoscopy to treat progressing midbrain tumor.


CLINICAL PRESENTATION
A 64-year-old man presented with an occasional double vision. A magnetic resonance imaging scan disclosed an enhancing lesion in the midbrain.


INTERVENTION
We performed a neuroendoscopic biopsy of the tumor and third ventriculostomy. Neuroendoscopy confirmed a bulging of the posterior commissure, which caused stenosis of the entrance of the aqueduct. Histological examination of the specimen obtained disclosed a diffuse astrocytoma. No permanent postoperative complications occurred although the patient felt slight double vision for 2 days after the operation. Conventional radiation therapy was supplemented.


CONCLUSION
Flexible neuroendoscopic biopsy with third ventriculostomy was a less-invasive and safer alternative for the progressing midbrain tumor bulging into the ventricles.