Brain changes in ruptured intracranial aneurysm.

Since the papers of Beadles (1907), Fearnsides (1916), and Symonds (1924), there have been numerous publications on the clinical manifestations, prognosis, and treatment of spontaneous subarachnoid haemorrhage. The pathology of the brain has received less attention. Many accounts have been taken from routine necropsy reports and few have included detailed examinations of the brain. Intracerebral bleeding has received most attention, largely since the paper of Richardson and Hyland (1941), but recently ischaemic lesions have been more widely recognized (Robertson, 1949; Wilson, Riggs, and Rupp, 1954; Bebin and Currier, 1957). Robertson (1949) described five instances of ischaemia, and it is noteworthy that three were seen in the 10 cases he observed himself, whereas only two were recorded in more than 80 routine post-mortem reports he reviewed. The greatest incidence of infarction is reported by Wilson et al. (1954), who noted focal ischaemic lesions in 45% of their necropsy material. No account, to my knowledge, however, gives details of the distribution, size, and importance of ischaemic lesions and their relation to other findings in the brain. This paper reports the brain findings in a series of 32 consecutive cases of fatal ruptured intracranial aneurysms. Two further instances have been excluded because surgical intervention made assessment of the pre-operative findings impossible. The ischaemic lesions found are described in detail, as are the instances of localized subarachnoid collections of blood (subarachnoid haematomata) which may well be important in the production of ischaemic lesions and intracerebral haemorrhage. Mention is also made of granular cell degeneration of the cerebellum which is uncommon and probably a terminal event.