Cranial Nerve Palsy after Onyx Embolization as a Treatment for Cerebral Vascular Malformation

The Onyx liquid embolic system is a relatively safe and commonly used treatment for vascular malformations, such as arteriovenous fistulas and arteriovenous malformations. However, studies on possible complications after Onyx embolization in patients with vascular malformations are limited, and the occurrence of cranial nerve palsy is occasionally reported. Here we report the progress of two different types of cranial nerve palsy that can occur after embolization. In both cases, Onyx embolization was performed to treat vascular malformations and ipsilateral oculomotor and facial nerve palsies were observed. Both patients were treated with steroids and exhibited symptom improvement after several months. The most common types of neuropathy that can occur after Onyx embolization are facial nerve palsy and trigeminal neuralgia. Although the mechanisms underlying these neuropathies are not clear, they may involve traction injuries sustained while extracting the microcatheter, mass effects resulting from thrombi and edema, or Onyx reflux into the vasa nervorum. In most cases, the neuropathy spontaneously resolves several months following the procedure.

Onyx embolization of lateral sinus dural arteriovenous fistula under the balloon protection:a follow-up analysis / 中国脑血管病杂志

Objective To preliminarily discuss the efficacy and safety of balloon protection technique in venous sinus in the embolization of lateral sinus dural arteriovenous fistula.Methods FromDecember 2012 to August 2016,7 consecutive patients with lateral sinus dural arteriovenous fistula embolized with Onyx under the protection of venous sinus balloon were enrolled retrospectively. Their clinical data,imaging data,and follow-up results were analyzed.Results In 7 patients,the fistulas of 3 cases were located in the sigmoid sinus and the fistulas of 4 cases were located in the transverse sinus. Immediately after operation, 5 patients were embolized completely and 2 were embolized mostly. All balloon protected venous sinuses maintained patency. Seven patients were followed up clinically and the follow-up time was 6-43 months. No new neurological deficits were observed. All 7 patients received whole DSA reexamination and the follow-up time was 6-11 months. It is suggested that 5 patients were completely cured,among them,the venous sinuses were patent in 4 cases,the venous sinus was occluded in 1 case;the fistula was stable and venous sinus patency in 1 case;and 1 had newly complicated venous sinus occlusion.Conclusion At the same time of embolization of the fistulas,the dural arteriovenous fistulas were embolized under the protection of venous sinus balloon. It could maintain long-term patency of venous sinus and be conductive to maintaining the stability of the embolization effect.

Spontaneous Aggressive Conversion of Venous Drainage Pattern in Dural Arteriovenous Fistula Treated with Onyx Embolization

We report a case of dural arteriovenous fistula (DAVF) that showed spontaneous conversion of venous drainage pattern from Borden type II to type III within a four month period of follow-up. Upon admission, the patient presented with aggravated neurologic status and newly developed seizure. After admission, endovascular embolization was performed through the middle meningeal artery with Onyx®. Complete obliteration of dural arteriovenous shunt was confirmed by angiography, and the patient's clinical symptoms improved. Although most cases of DAVF show benign clinical course and conversion pattern, close follow-up is required to detect potential aggravation.

Transcranial Direct Middle Meningeal Artery Puncture for the Onyx Embolization of Dural Arteriovenous Fistula Involving the Superior Sagittal Sinus

A 66-year-old woman presented with intermittent paraparesis and generalized tonic-clonic seizure. Cerebral angiography demonstrated dural arteriovenous fistula (AVF) involving superior sagittal sinus (SSS), which was associated with SSS occlusion on the posterior one third. The dural AVF was fed by bilateral middle meningeal arteries (MMAs), superficial temporal arteries (STAs) and occipital arteries with marked retrograde cortical venous reflux. Transfemoral arterial Onyx embolization was performed through right MMA and STA, but it was not successful, which resulted in partial obliteration of dural AVF because of tortuous MMA preventing the microcatheter from reaching the fistula closely enough. Second procedure was performed through left MMA accessed by direct MMA puncture following small decortications of cranium overlying the MMA using diamond drill one week later. Microcatheter could be located far distally to the fistula through 5 F sheath placed into the MMA and complete obliteration of dural AVF was achieved using 3.9 cc of Onyx.