SURG-21. SUPRACEREBELLAR TRANSTENTORIAL APPROACH FOR OCCIPITAL MENINGIOMA TO MAXIMIZE VISUAL PRESERVATION: TECHNICAL NOTE

Abstract

BACKGROUND

Surgery for resection of tentorial meningiomas that compress the primary visual cortex has a significant risk of worsening vision. This concern is especially acute in patients with a preexisting visual deficit. Approaches that involve mechanical retraction of the occipital lobe further threaten visual function. The supracerebellar transtentorial (SCTT) approach, which does not carry a risk of retraction injury, should be considered for occipital tentorial meningioma to maximize functional visual outcomes. CLINICAL PRESENTATION: A 54-year-old woman underwent two resections and radiation therapy for a right occipital oligodendroglioma as a teenager. She was left with a complete left homonymous hemianopsia. The patient now presented with progressive vision loss in her remaining right visual field. Imaging revealed a left occipital superiorly projecting tentorial meningioma. Given that preserving remaining visual function was of critical importance in this case, the SCTT approach with the patient in the prone position was chosen for resection. Traditionally favored suboccipital lateral and occipital interhemispheric supratentorial approaches risked retraction injury to visual cortex and further visual loss. A transcortical or transfalcine approach, also considered given access via the large right occipital resection cavity, would similarly require manipulation of the remaining medial rim of left occipital lobe. A Simpson grade 1 resection was achieved without disrupting the occipital lobe pia or requiring cerebellar retraction while minimizing intraoperative risk of air embolism. A diagnosis of a WHO grade II meningioma (presumably radiation induced) was made. The patients vision returned to pre-morbid baseline one week after surgery.

CONCLUSION

The SCTT approach should be considered for the surgical management of patients with occipital tentorial meningiomas when visual preservation is at risk. This approach avoids transgression of visual cortex, and minimizes the risk of venous infarction or contusions from retraction injury.