The diagnosis of cerebral angioma.

The cerebral angioma is an arterio-venous communication of congenital origin and in its structure does not differ essentially from similar malformations elsewhere. Their occasional presence in the brain was already known to pathologists nearly Ioo years ago and the first presumptive clinical diagnosis was made in I898. This was in a patient who had a left spastic hemiparesis and a loud bruit, audible over the whole head. Thereafter an increasing number of cases was found, in the early years of this century usually as a surprise finding at autopsy and later, with the development of neurosurgery, at operation for suspected cerebral tumour. Throughout these years the clinical picture was gradually taking shape. It is, however, with the development of arteriography and especially with the perfection of the percutaneous method within the last few years that the most recent and the most considerable advance in our knowledge of the clinical behaviour of these malformations has been made. Collapsed at autopsy and only partly exposed at operation, their structure has only been fully visualised and their true incidence appreciated by arteriography. Thus it now seems likely that all are composed both of arteries and veins, although in greatly varying proportion, and are arterio-venous malformations. They are of all sizes, the smallest being so small as possibly to escape notice by any other method of inspection. The incidence is about i per cent. of all neurosurgical and neurological admissions, males and females being about equally affected. Although ultimately a radiological diagnosis, the clinical picture may at times be so well-defined as to allow of a confident diagnosis at the bed-side. In most cases, however, the diagnosis will be put forward on clinical grounds as a possibility, immediate or remote, and occasionally an angioma will be discovered by arteriography when quite unsuspected. It is the purpose of this paper to draw attention to clinical features of the cerebral angioma which might suggest the diagnosis and thereby also suggest arteriography as the radiological investigation of choice. Symptoms Although supposedly of congenital origin, the cerebral angioma does not immediately manifest itself and only about o per cent. of patients harbouring one will have a relevant symptom in the first decade of life. More than half will have a presenting symptom in the next two decades and 70 per cent. will have had one before the age of 30. The remaining 30 per cent. present with decreasing frequency during the next 20o years and presentation is extremely rare but not unknown over the age of 50. The ways in which angiomas commonly present are by causing haemorrhage, epilepsy, headache or hemiparesis and their further course may be characterized, if sufficiently prolonged, by a combination of two or more of these symptoms.