INTRACRANIAL COMPLICATIONS 363 attempting to eat. The stupor deepens to coma, which continues till death. PROGNOSIS. The prognosis of abscess of the brain is still grave. The statistics of various authorities differ, but it may be said that the early recognition and neurosurgical treatment of otogenic intracranial infection combined with antibiotic therapy have reduced the mortality to the region of 10 per cent or less. In adults recovery may be followed several months later by epilep- tiform attacks. Even after the apparently successful evacuation of an abscess, death may occur from spread of the infection. Those cases are least hopeful Fig. 188. Exposure of dura of middle cranial fossa on left side preliminary to drainage of temporal lobe abscess. in which more than one abscess is present, or which are complicated by sinus thrombosis or meningitis. TREATMENT. When the site of the abscess has been localized it is drained through a burr hole in the squamous temporal in cases of temporal lobe abscess, and midway between the mastoid and the external occipital pro- tuberance hi cerebellar abscess. When the abscess is located and pus aspirated 30 000-50 000 units of pure crystalline penicillin mixed with 2 ml of thin barium emulsion should be injected and the wound closed. Progress can be checked by radiographs every few days. Should the abscess increase in size or remain stationary it may be excised by the neurosurgeon, but should it shrivel excision is not required. A cure is claimed when the cerebrospinal fluid and air encephalogram are normal. The otologist should co-operate closely with the neurosurgeon in the treatment of brain abscess, and mastoid surgery (Fig. 188) may be necessary to remove the source of the infection, and to deal with any extradural abscess or an accompanying sinus throm- bosis. Such mastoid surgery should be performed early in the disease and the wound left unsutured, to be closed after the brain abscess shows improvement.