ANASTOMOSIS BETWEEN THE ANTERIOR CHOROIDAL ARTERY AND THE POSTERIOR CEREBRAL ARTERY DEMONSTRATED BY ARTERIOGRAPHY.

Abstract

Leptomeningeal anastomoses between the major cerebral arteries have been previously described in anatomical studies (1–4). The possible significance of these anastomoses has become an object of particular interest, as radiographic studies of the cerebral vessels have become increasingly frequent in cases of apoplectic insults (5–11). Anastomoses between the anterior choroidal and the posterior choroidal artery, and even directly between the anterior choroidal artery and the posterior cerebral artery, have been mentioned by different authors in anatomical studies (2, 3, 12–15). Krayenbühl and Yaṣargil in their angiographic study of the cerebral collateral circulation (11) described a “circulus arteriosus intracerebralis,” i.e., anastomosis between the anterior and the “posterior” choroidal arteries. A vertebral arteriogram from a case of occlusion of the internal carotid artery illustrates their study, and they describe filling of the pericallosal artery and some insula arteries (“über die Kollateralen von A. cerebralis posterior, A. chorioidea posterior”). Unfortunately, it is not quite obvious from the text, nor from the reproduction of the arteriogram, how the contrast has reached the insula arteries: whether through peripheral leptomeningeal anastomoses between the posterior and the middle cerebral arteries or through the above-mentioned “circulus arteriosus intracerebralis,” or by both routes. Reviewing the radiological literature we failed to find any other case of radiographic demonstration, except postmortem (15), of these anastomoses, so well known to the anatomists. In the course of a study of occlusion of the middle cerebral artery, which will be published later, we have found one case where the function of the anastomoses between the anterior choroidal artery and the posterior cerebral artery could be observed on the arteriogram. Our patient was a 57-year-old female, who within the last three months had had three attacks of right-sided hemiparesis and aphasia, each time followed by full remission. She was admitted to the Kommune-hospitalet Copenhagen Oct. 31, 1958, after a new stroke with symptoms as previously. The blood pressure on the day of admission was 230/130, hemoglobin 105 per cent. Lumbar puncture (Nov. 11) showed clear, colorless spinal fluid with 49 mg. per cent protein, 32/3 leukocytes and no erythrocytes. The day after admission the patient was observed to have difficulty in swallowing; apart from that, however, no symptoms which pointed toward the brain stem were observed. Arteriography (Nov. 13) by way of the left common carotid artery revealed a total occlusion of the left middle cerebral artery a few millimeters from the division of the internal carotid artery.