Early venous filling in cranial angiography.

Abstract

Early venous filling in cerebral angiography is usually indicative of a primary or secondary neoplasm of the brain. Arteriovenous malformations, accounting for 4 per cent of all brain lesions (1) are a less common cause. With the advent of routine serial angiography, unusual causes of rapid venous filling have been seen. During the past several years we have observed 47 cases of arteriovenous shunting (early venous filling) not due to a primary or secondary intracerebral neoplasm or an arteriovenous malformation (Table I). Our experience with these disease processes is the subject of this report. Early venous filling is said to be present when there is progression from the arterial filling phase to the venous phase without an obvious or apparent intervening arterial emptying or capillary phase. Local or diffuse decrease in circulation time with an orderly progression of the arterial-venous phase also represents early venous filling. Only in this latter situation have we not used the term arteriovenous shunting interchangeably with early venous filling. Except in one case (meningitis) in which there was diffuse arteriovenous shunting, early venous filling was restricted to the local area of pathology. In this communication each general cause of this vascular phenomenon is discussed individually. I. Arteriovenous Fistula Of the 18 arteriovenous fistulas seen, 12 were carotid artery-cavernous sinus (Fig. 1), 4 carotid artery-jugular vein (Fig. 2), one superficial temporal artery-vein, and one vertebral artery-vein. All cases were post-traumatic. Arteriovenous fistula implies communication between the arterial and venous systems without an intervening arteriolar-capillary network. The first two recognized cases of arteriovenous fistulas were reported by W. Hunter in 1762 as post-phlebotomy complications of the arm (2). Most intracranial arteriovenous fistulas are post-traumatic in nature. The common site of involvement is the carotid artery-cavernous sinus level secondary to fracture at the base of the skull. In Locke's series of 544 cases of carotid cavernous fistula, 76.8 per cent were traumatic and 23.29 per cent were spontaneous (3). Spontaneous fistulas may arise from carotid cavernous aneurysms that rupture into the cavernous sinus. The exact site of origin of these aneurysms is variable as there are many branches of the cavernous carotid artery. A detailed anatomy of these vessels may be found in the papers by Parkinson (4, 5). Bilateral carotid-cavernous fistulas, although extremely rare, have been reported (6). Extracranial arteriovenous fistulas involving the carotid artery and jugular vein are usually secondary to trauma during manipulation for carotid artery puncture or secondary to a penetrating wound. Intentional carotid-jugular fistulas have been established in the past in an attempt to revascularize the brain via a retrograde route (7).