Virus Diseases in Man Animal and Plant

in 15 per cent of these cases. The internal carotid artery was the site of the aneurysm in 35.4 per cent of the patients, while the remainder were almost equally divided between (1) the anterior cerebral and anterior communicating arteries, (2) the middle cerebral, and (3) the basilar and vertebral arteries. The aneurysms are classified into three categories; mycotic, 6; arteriosclerotic, 22; and the remainder, congenital. The aneurysms had ruptured in 64 cases; in 44 no bleeding had occurred. Over 50 per cent of the patients with a ruptured aneurysm died within 48 hours. More than one hemorrhage was recorded in 40 per cent of the cases. One chapter is devoted to a detailed description of the embryology and anatomy of the circle of Willis. Aids in diagnosis and localization are discussed fully. The author states that an absolute prerequisite to any form of treatment of an intracranial aneurysm involving the internal carotid or its branches is knowledge of the potential collateral circulation. He states, "If temporary occlusion of the internal carotid in the neck cannot be tolerated for ten minutes, an attack upon any type of aneurysm would be hazardous and probably fatal." The "trapping" of a carotid aneurysm is accomplished by ligature (fascial band) in the neck and clipping the neck of the aneurysmal sac intracranially. This double procedure was done for 10 aneurysms located in the carotid canal and 16 aneurysms on the intracranial portion of the carotid with 18 "cured." Partial or total occlusion of the internal carotid artery in the neck was done in 61 cases, and clipping intracranially was done in 27 cases. Immediate and late circulatory disturbances occurred in 6; there were 4 deaths. The author ascribes these excellent results to the utilization of the Matas test and partial ligation of the carotid when this is indicated. Circulatory disturbances after carotid ligation are explained on the basis of inadequate collateral circulation or a propagating thrombus or an embolus. In the opinion of the author, thrombus formation may result from damage to the intima and he suggests that a double fascial band be interposed between the wall of the carotid and the ligature. The importance of guarding against injuries to the posterior communicating artery in handling an intracranial carotid aneurysm is stressed. BERNARD S. BRODY.