Neuroradiology (1991) 33:6546 Neuro-- radiology 9 Springer-Verlag 1991 Case reports Spontaneous closure of an intracranial middle cerebral arteriovenous fistula C. Santosh 1 , E. Teasdale 1, and A. Molyneux ~ 1 Department of Neuroradiology, Institute of Neurological Sciences, Southern General Hospital, Glasgow, UK z Department of Neuroradiology, Radcliffe Infirmary, Oxford, UK Received: 17 May 1990 Summary. This case report concerns the spontaneous clo- sure of a middle cerebral arteriovenous fistula, lesions which are normally treated by surgery or interventional therapy. We have been unable to find any previous report of spontaneous closure of a similar fistula. Key words: Spontaneous closure - Middle cerebral arte- riovenous fistula The most common form of intracranial arteriovenous fis- tula (AVF) with giant venous varix is in relation to the vein of Galen. In this group there are many sub types. AVFs at other sites are rare. Patients with giant intracranial varices can present with signs and symptoms of raised intracranial pressure, seizures from cortical irritation, intracranial haemorrhage or cardiac decompensation depending upon the site and size of the lesion [1]. This case report concerns a middle cerebral AVF which underwent spontaneous clo- sure. Case report A 45-year-old female with a long history of epilepsy well controlled on Tegretol, Mysoline and Ethosuximide, gave a three year history of bifrontal headache and right sided earache and described a noise like a "rushing train" in re- lation to the right ear which had been present for nine months. In the two months prior to admission she was in- creasingly unsteady on her feet and tended to fall to the right. An audiogram showed low frequency hearing loss on the right. CT scan carried out without and with in- travenous contrast demonstrated a large irregular mass with curvilinear calcification and associated low attenua- tion in the right temporal region. Regions of enhancement were seen within some of the calcified areas. Angiography showed an intracranial fistula between the temporal branch of the middle cerebral artery and a large sylvian vein draining into the transverse sinus (Fig. 2). Not all the areas of calcification in relation to the varicosity showed evidence of venous filling on the angio- gram (Fig. 1). It was decided that the best way to treat this was by detachable balloon occlusion, for which she was readmitted 10 days later. On this occasion she gave a his- tory that approximately three days earfier she had de- veloped sudden onset of severe pain in the right temporal region associated with a cessation of the tinnitus. Auscul- tation failed to reveal any bruit. Repeat angiogram dem- onstrated spontaneous closure of the fistula, with normal filling of the branches of the middle cerebral artery (Fig. 3). Discussion Vinuela et al. [2] discussed the entity of non-Galenic AVF with giant varices. He reported eight cases, seven of which underwent interventional or surgical therapy, the remain- ing patient was treated conservatively. A few cases of spontaneous thrombosis of vein of Galen aneurysms have been reported [3, 4] and throm- bosis and closure of carotico-cavernous fistulae have also been described during cerebral angiography, provoked by various mechanisms such as embolism by fibrin platelet clots, fall in blood pressure and/or the injection of contrast [5]. In this case, the initial CT scan showed partial throm- bosis of the venous varix which was confirmed on the first angiogram. Closure of the fistula occurred after the initial angiogram and so it seems likely that the angiogram has- tened the natural process of spontaneous thrombosis within this fistula. Should the fistula recur appropriate management will need to be reviewed.