Aneurysms are acquired lesions related to hemodynamic stress on the arterial walls at bifurcation points and bends. Saccular or berry aneurysms are specific to the intracranial arteries because their walls lack an external elastic lamina and contain a very thin adventitia—factors that may predispose to the formation of aneurysms.
An additional feature is that they lie unsupported in the subarachnoid space. Methods Data were obtained for each of Canada’s 10 provinces for the 10 fiscal years 1982 through 1991. All hospitalizations of persons 15 years of age or older with a primary diagnosis at discharge coded 430 according to the International Classification of Diseases, 9th Revision, were included. Rates of SAH per 100 000 population were calculated for men and women for 5-year age groups, by calendar year, and by season.
Treatement is • Remove large collections of blood or relieve pressure on the brain if thehemorrhage is due to an injury • Repair the aneurysm if the hemorrhage is due to an aneurysm rupture If the person is critically ill, surgery may have to wait until the person is more stable. Ongoing Research is being done at Subarachnoid haemorrhage centres.