LAUSR

BACKGROUND Cerebral venous complications related to neurosurgical interventions are only rarely reported in the literature. Internal cerebral veins (ICVs) are vulnerable to injury during neurosurgical approaches to the pineal and thalamic regions. The occurrence of unilateral postoperative ICV thrombosis in children is extremely rare, with only two such cases reported thus far. CASE DESCRIPTION A 15-year-old child presented to the emergency department with headache, persistent vomiting and pronounced lethargy for three days. Magnetic resonance imaging (MRI) of the brain was performed and showed a large solid-cystic mass at the pineal region, resulting in upstream hydrocephalus. Serum beta-HCG was elevated and a diagnosis of germ cell tumour was made. Patient was commenced on neo-adjuvant chemotherapy with partial response on repeat imaging after three courses of chemotherapy. Decision was made to proceed with surgical resection of the residual tumour. MRI brain performed on post-operative day one showed multiple foci of restricted diffusion in the right cerebral deep white matter, giving rise to a "string of pearls" appearance. There is also absence of enhancement of the right internal cerebral vein (ICV), suspicious for deep cerebral venous thrombosis. This was confirmed on subsequent CT venogram. CONCLUSIONS Our reported case adds to the limited literature on postoperative ICV thrombosis in children and describes a unique imaging phenotype of venous watershed infarcts. Neurosurgeons and neuroradiologists should be aware of this unique imaging phenotype and have a high index of suspicion for deep cerebral venous thrombosis, especially in patients with prior neurosurgical intervention in the pineal or thalamic regions.