[Intravenous radioisotope angiography in carotid-cavernous fistula]

The use of intravenous radio-isotope angiography in 3 cases of unilateral carotid-cavernous sinus fistula is described. The lesion gives a characteristic image pattern distinguishable from that of arteriovenous malformation in this region. An abnormal registration of intense radioactivity is seen in the early phases, accurately localised to the cavernous sinus, with a distinctive sigmoid-shaped configuration. Rapid disappearance by a paradoxical apparent increase in blood flow to the ipsilateral hemicranium. This is attributed to the massively arterialised venous drainage. This technique of demonstrating the cerebral circulation dynamically is considered a valuable diagnostic supplement to the static scintiscan and to conventional roentgen arteriography in this lesion.