Posterior-fossa haemorrhage after supratentorial surgery - Report of threecases and review of the literature

We present clinical details of three patients with posterior fossa haemorrh age after supratentorial surgery and discuss possible pathomechanisms of th is rare complication. All patients were males of advanced age. Two patients presented with a history of hypertension. In all patients the occurence of haemorrhage was associated with loss/removal of large amounts of cerebrosp inal fluid (CSF) either intra-operatively (one patient undergoing aneurysm surgery) or postoperatively (all three patients: drainage of subdural hygro mas or chronic subdural haematomas in two, external Ventricular drainage in one patient). Treatment consisted in haematoma evacuation and/ or external ventricular drainage. Two patients died, one patient recovered completely. Although haematomas distant from a craniotomy site are a well known entity, a review of the literature identified only 25 published cases of posterior fossa haemorrhage after supratentorial procedures in the CT era. Most ofte n disturbances of coagulation, positioning of the patient and episodes of h ypertension have been associated with this complication. Only one author de scribed the occurence of a haemorrhage after drainage of a supratentorial h ygroma. We suggest that the loss of large amounts of CSF intra-operatively and postoperatively may lead to parenchymal shifts or a critical increase o f transmural venous pressure with subsequent vascular disruption and haemor rhage.