Saturday 1 October 2016

A focal Vermian bleed on MRI


This MRI study of brain reveals an ~ 12x13mm well defined round to ovoid nodular lesion in cerebellar vermis at the roof of fourth ventricle. Lesion is bright on T1 with high signal on T2 suggestive of blood degradation product with low signal on GRE. No marked peri lesional odema. No significant mass effect or mid line shift.

Imaging wise diagnosis suggested was Tumor nodule with bleed, however possibility of underlying vascular malformation can not be ruled out on imaging.

Operated with posterior fossa craniotomy. E/o complete excision of lesion on post operative scans. No major extra / intra axial bleed.


Specimen         : Excisional biopsy – SOL in base of skull (cerebellar vermis). 
Gross Appearance    : The specimen consists of few irregular soft pieces of dull greyish white tissue; together measuring 0.3X0.3X0.2 cm. The entire tissue is submitted for processing.    

Microscopy        : Section and additional made serial deeper section shows fragmented bits of reactive cerebellar tissue with the central portion showing ectatic vascular channel with undulating wall, devoid of smooth muscle and elastic lamellae. Also seen are couple of fragments with microhaemorrhage and scattered haemosiderophages along with prominent perivascular lymphocytic cuffing. There is no evidence of malignancy. 

Final Diagnosis  : Bleed secondary to Cavernous Angioma (Cavernoma).