Fig. 4
From: Crossed brainstem syndrome revealing bleeding brainstem cavernous malformation: an illustrative case
Important surgical sequences. a Hockey stick fashion opening of the dura mater, discovering the cerebellar notch medially, and the left superior and inferior semilunar lobules. b The floor of the fourth ventricle appears after passing through the inferior medullary velum, and displays crucial anatomical landmarks such as the striae medullares (SM), the infrafacial triangle (IFT) just above and the hypoglossal triangle (HT) underneath. The exophytic hematoma appears clearly on the left side at the level of the striae medullares. The cerebellar developmental venous anomaly (DVA) appears in blue under a thin layer of nervous tissue. c Evacuation of the pontine hematoma (H) at the level of the infrafacial triangle (IFT), just above the striae medullares (SM) The midline is marked with a dotted line. d En-bloc excision of the cavernous malformation (CAV) using a tumor’s clamp. e Resection cavity