Arteriovenous malformation associated with cyst in a child: Case report and review of literature
An 8-year-old boy presented with history of generalized tonic clonic seizures for the last 2 years. There was no history of sudden onset headache or neurological deficits, suggestive of bleed. On examination, there were no focal neurological deficits. An MRI was performed, which showed a nidus, seen as flow voids, in the medial parietal lobe on the right side with a large cystic area abutting it posteriorly. This was hyperintense on T2-weighted images and inverted completely on FLAIR images [Figure and ]. There was no evidence of hemorrhage on SWI (susceptibility-weighted images). A digital subtraction angiogram was subsequently performed, which showed the nidus was receiving arterial feeders from the pericallosal branches of the right anterior cerebral artery and draining into the superior sagittal sinus via cortical veins [Figure and ].\nVarious treatment options were discussed, and the patient was offered surgical excision of the AVM as the first choice. He underwent a parietal craniotomy and excision of the AVM. The AVM nidus and the draining vein was seen on the surface, and below that, there was a large cyst containing about 30 mL of clear fluid. The appearance of the fluid was like that of CSF. The AVM was completely excised, and the cyst was drained. Histological examination of the nidus showed abnormal arterial and venous channels, and the cyst wall had numerous thin-walled vascular channels containing hemosiderin in the fibrous tissue.\nA post-operative angiogram was done on post-operative day two, which showed complete excision of the nidus [Figure and ]. His post-operative stay in the hospital was uneventful, and was discharged on the third post-operative day. At 6-month follow-up, patient is neurologically normal, and is seizure-free on a single anti-epileptic drug.