The familial incidence of intracranial aneurysms.

The occurrence of familial cerebral aneurysms lends support to the importance of congenital factors in their pathogenesis. The information on the subject is, however, still meagre, there being less than 20 reports in literature. Earlier literature mentions the occurrence of cerebrovascular accidents in members of the same family with polycystic kidneys (Dunger, 1904). Tonnis and Lange-Cosack (1953) reported angiomas in several members of one family. O'Brien (1942) reported a case with a middle cerebral artery aneurysm whose twin brother might have died from an 'acute cerebrovascular episode' eight years previously. Sudden death in identical twins from such diseases was described by Jokl and Wolffe (1954), but at necropsy evidence was lacking in their report. In the same year, Chambers, Harper, and Simpson (1954) reported proven ruptured aneurysms in father and son, on the middle cerebral artery and the anterior communicating artery respectively. In Bruce's revision of Wilson's Neurology (Wilson, 1955), similar mention is made of 'evidence of their dysplastic origin is afforded by occasional appearance in more than one member of a family', without further details. Walton (1956)described six instances of familial subarachnoid haemorrhage, but no specific details were given. Ross (1959) described a woman with left parieto-occipital angioma and left middle cerebral artery aneurysm whose mother had died of a recurrent subarachnoid haemorrhage after ligation of the carotid artery for a posterior communicating artery aneurysm. Ullrich and Sugar (1960) reported similar disorders in a man with a middle cerebral artery aneurysm whose brother had died after surgery for an anterior communicating artery aneurysm, two brothers who had middle cerebral artery aneurysms on opposite sides of head, a man with multiple (four) aneurysms whose brother had died of a 'cerebkal haemorrhage' (no necropsy) and the brother's son had also died after subarachnoid haemorrhage due to an aneurysm at the junction of the anterior cerebral and the anterior communicating arteries, and a brother-sister pair with internal carotid artery