Considerations on the origin of subarachnoid hemorrhages.

The Authors emphasize the importance of C.T. in the study of subarachnoid hemorrhages. By means of this new radiological investigation they are able to exclude a vascular or tumoral etiology in those patients who had no aneurysms detectable by cerebral angiography, and suggest the problem of the so-called spontaneous subarachnoid hemorrhages. They discuss the degenerative nature of the endocranial aneurysms. Several interesting case-reports stress the importance of the primitive lesions of the arterial wall vessel in the degenerative origin of endocranial aneurysms.