See under This word simply means that the membranes which line the inside of the skull and spinal canal have become inflamed. An outbreak of meningitis in the community will cause alarm because the cause is likely to be a virulent micro-organism that can cause serious illness or even death. Following surgery upon the brain, however, inflammation of the lining membranes can result from irritation by even small amounts blood products or muscle protein, which are inevitably “spilt” during surgery. The term chemical meningitis, or aseptic meningitis, is used to refer to this condition. It is self-limiting and not usually life- threatening but it needs to be distinguished from the more serious bacterial meningitis, which can also occasionally complicate intracranial surgery..