Utility of manual venous compression during transvenous Onyx injection for a scalp arteriovenous fistula: illustrative case

Abstract

BACKGROUND When performing transvenous liquid embolization for scalp arteriovenous fistulas, multiple networks of venous drainage could limit effective retrograde penetration of embolic agents into feeding arteries, resulting in incomplete obliteration. A salvage technique to achieve effective Onyx penetration with manual venous compression during transvenous embolization is demonstrated. OBSERVATIONS A 43-year-old man presented with a progressively enlarging mass on his left temporal scalp that was first noticed approximately 20 years earlier. External carotid artery injection showed two scalp arteriovenous fistulas (AVFs). The patient received endovascular embolization. After successful transarterial obliteration of one AVF, transvenous Onyx embolization was performed for another AVF located in the subcutaneous layer. To avoid unnecessary Onyx migration into multiple venous networks, several coils were put in a venous pouch as a scaffold for the Onyx, and feeding arteries were temporarily occluded. Despite these adjunctive techniques, the Onyx migrated into multiple veins and even toward the orbit without complete fistula obliteration. Thereafter, Onyx was injected under manual compression of venous outlets from the pouch, resulting in complete obliteration. LESSONS Manual compression of venous outlets can be used as a salvage procedure during transvenous Onyx embolization for a scalp AVF. A surgeon’s radiation exposure can be reduced by step-by-step adjunctive procedures.

Direct Puncture of the Superficial Temporal Artery in Embolization of a Scalp Arteriovenous Fistula: A Case Report

“…They can develop from the subcutaneous layer and create a communication intracranially or to any neighboring venous network, even involving the orbital or auricular vasculature. 1,2 Most recently, Clarençon et al and other groups [1][2][3][4][5] have described direct scalp puncture of the superficial temporal artery feeding an intracranial fistulous shunt point. The direct puncture by Clarençon et al 3 was performed after multiple access failures from more traditional sites.…”

“…These lesions can occur spontaneously, post radiation, or following any sort of trauma – whether it be from surgical trauma to the tissue or blunt force. They can develop from the subcutaneous layer and create a communication intracranially or to any neighboring venous network, even involving the orbital or auricular vasculature [ 1 , 2 ]. Most recently, Clarençon et al and other groups [ 1 - 5 ] have described direct scalp puncture of the superficial temporal artery feeding an intracranial fistulous shunt point.…”

“…Puncture of the extracranial artery itself has been described [1][2][3][4][5] to circumvent proximal tortuous anatomy of scalp AVF that may be impossible to navigate with a microcatheter and microwire. Herein we describe the successful embolization of a large scalp AVF with direct puncture of the lesion itself.…”