Contralateral Extradural Haematoma after Insertion of a Programmable-Valve Ventriculoperitoneal Shunt

A 13-year-old boy was investigated by the paediatric neurology department for unexplained episodic screaming and behavioural difficulties at school. He was observed to be withdrawn and to walk with a stooped posture. His height and weight were on the 25th centile and his head circumference was on the 75th centile. An electroencephalogram showed activity consistent with temporal lobe epilepsy and a diagnosis of complex partial seizures was made. Magnetic resonance imaging of his brain at that time showed moderate dilatation of the third and lateral ventricles, a narrow aqueduct and a small fourth ventricle. No focal abnormality was seen and the provisional diagnosis was congenital aqueduct stenosis. There was no evidence of raised intracranial pressure (ICP) so no invasive ICP monitoring was done. He was treated with carbamazepine and after 2 years he was intellectually intact and all seizure activity had ceased. His anticonvulsants were stopped and he was discharged from follow-up. He was symptom-free for 5 years until he was 20, when he was seen in the neurosurgical department after a grand mal seizure. His Glasgow coma score (GCS) was 12 and an urgent computed tomography (CT) scan of his head showed dilatation of the lateral and third ventricles, suggesting acute hydrocephalus (Figure 1). He underwent emergency insertion of a right frontal ventriculoperitoneal (VP) shunt with a programmable valve set at 100mm H20 pressure and an anti-siphon device distal to the valve3. Three hours later he had a further grand mal seizure on the ward and his GCS dropped to 4. Repeat CT showed a massive left-sided extradural haemorrhage with midline shift to the right and a right-sided subdural cerebrospinal fluid (CSF) collection (Figure 2). At emergency left fronto-temporoparietal craniotomy a large left-sided extradural collection was drained and the dura was tented to the skull to prevent reaccumulation. The valve was reprogrammed to an opening pressure of 180 mm H20. Postoperatively he had a right hemiparesis but obeyed commands with his left arm. There was moderate weakness of the right 7th cranial nerve and mild weakness of the right 9th, 1 0th and 1 1 th nerves. He was transferred to the neurosurgical critical care unit and was eventually extubated after nine days. His speech and swallow improved considerably over the subsequent week and he regained power of 3/5 in the right lower limb. He was admitted to the rehabilitation unit where he had two further episodes of Department of Surgery, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK