Bilateral sixth nerve palsies from carotid cavernous fistulas with transient worsening following transvenous embolisation

A 59-year-old man presented with a 2-week history of binocular horizontal diplopia worse when looking to the left. He was diagnosed with a left sixth nerve palsy (6 NP) and had new bilateral findings at a 2-week follow-up with new dilated episcleral blood vessels. Bilateral carotid-cavernous fistulas (CCFs) were suspected and confirmed with CT angiography and catheter angiography. He underwent successful coil and Onyx embolisation of the left cavernous sinus and immediately noticed worsening of the double vision when looking left due to a worse left 6 NP. Three weeks later, he underwent similar treatment of the right CCF and immediately noticed worsening of the double vision when looking to the right and was found to have a worse right 6 NP. His double vision resolved 6 months later. CCFs are rare causes of bilateral 6 NPs and although there is a good prognosis, symptoms may worsen after treatment.

The variant with the absence of the superior petrosal venous and sinus: A potential pitfall of transvenous balloon-assisted embolisation of Borden type II transverse-sigmoid dural arteriovenous fistula

We describe a patient with Borden type II transverse-sigmoid dural arteriovenous fistula. On the venous phase of the left vertebral artery injection, there was no superior petrosal veins and sinus on the side of lesion. After transvenous balloon-assisted Onyx embolisation, the patient developed extensive venous infarction from venous occlusion. This report calls attention to a highly unusual variant in which the superior petrosal veins and sinus are absent, and the cerebellar veins will be drained by tributaries of the bridging veins in this circumstance. In such circumstances, occlusion of the bridging vein on the tentorial cerebellar surface may lead to complications during transverse-sigmoid dural arteriovenous fistula embolisation.

Asystole during onyx embolisation of a dural AV fistula: The trigeminocardiac reflex

There are fewer than 20 published case reports of bradycardia or asystole during intracranial embolisation procedures. These are well described in open neurosurgical procedures, particularly involving the skull base. We present a case of a 59-year-old male patient who presented for elective embolisation of a dural arteriovenous fistula. During the injection of Onyx, the patient experience sudden asystole, which recurred after a second Onyx injection. Following successful treatment, a third injection proceeded without incident.

Republished: Development of syndrome of inappropriate antidiuretic hormone secretion (SIADH) after Onyx embolisation of a cavernous carotid fistula

Patients with cavernous carotid fistulas (CCFs) can present with pituitary hypoperfusion and hypopituitarism; however, there are no previous reports of pituitary or hormonal abnormalities developing after CCF embolisation in an asymptomatic patient. We describe a patient with no hormonal abnormalities who developed syndrome of inappropriate antidiuretic hormone (SIADH) secretion after CCF embolisation. The patient had bilateral indirect CCFs, which were completely embolised via a transvenous approach, and was neurologically stable postoperatively and discharged. In the subsequent 2 weeks the patient was readmitted twice for acute hyponatraemia and a tonic-clonic seizure. Laboratory studies revealed severe SIADH. Clinical status and sodium levels improved after treatment. One year later the patient was weaned off all medications and remained neurologically stable. SIADH may be a delayed phenomenon after CCF embolisation. Given the proximity of embolised vessels to the pituitary's vascular supply, CCF treatment may result in flow disturbance, ischaemia and hormonal abnormalities.