Treatment of low flow, indirect cavernous sinus dural arteriovenous fistulas with external manual carotid compression - the UK experience.

External manual carotid compression (EMCC) is a treatment option for indirect cavernous sinus dural arteriovenous fistulas (CS-DAVF). The exact mechanism of how this works is unclear but compression of the carotid and jugular produces thrombus in the cavernous sinus (CS). Although compression of the superior ophthalmic vein (SOV) has been described as a treatment option this technique is not always amenable. We studied the clinical features, imaging studies, complications and resolution of CS-DAVF in a series seven patients. Between 2011 and 2017 we treated 7 patients (4 female, 3 male, age range: 60-86 years) with EMCC for an indirect, low-flow CS-DAVF (Barrow B-D). Patients compressed the cervical carotid artery on the side of the CS-DAVF using the contralateral hand for 5-10 seconds 5-10 times per day. Using gradually increasing pressure they compressed the carotid artery and jugular vein until the pulse was no longer palpable. 6 patients had complete resolution of their CS-DAVF within a range of 5-24 months of symptom onset (median 8 months). 5 of our patients had complete resolution of their clinical symptoms at final follow-up. One patient had a failed endovascular procedure, and subsequently underwent surgery to cannulate the SOV for a transvenous endovascular approach to the fistula but in the meantime she had performed EMCC, which is thought to have resolved the fistula. One patient remains under follow-up and is performing EMCC. EMCC is a safe and low risk technique for low-flow indirect CS-DAVF and should be considered as a first line treatment for patients unable to have endovascular treatment. Although compression of the SOV has been described this can often be difficult to perform in the context of periorbital oedema. EMCC should always be performed using the contralateral hand, because this will ensure that the compressing hand falls away should cerebral ischaemia develop.