Angioarchitecture of Transverse-Sigmoid Sinus Dural Arteriovenous Fistulas: Evaluation of Shunted Pouches by Multiplanar Reformatted Images of Rotational Angiography

Type IIa transverse-sigmoid sinus dural arteriovenous fistulas with multiple shunted pouches. The DAVFs were associated with paraganglioma at the ipsilateral carotid bifurcation. A, Lateral view of right external carotid angiography shows DAVFs involving the transverse and sigmoid sinuses. The DAVFs are fed by the middle meningeal artery, the posterior auricular artery, and the occipital artery and drain into the right jugular vein and the contralateral transverse sinus. B, The axial reformatted images show multiple SPs (SP 1–3), which are located at the sigmoid-jugular junction (SP1), mediodorsal to the vertical portion of the sigmoid sinus (SP2), and at the transverse-sigmoid junction (SP3), respectively. The transosseous feeders from the stylomastoid branches (SMB) of the posterior auricular arteries supply the SP1; the transosseous branch (TOB) of the occipital artery and the posterior auricular artery supply the SP2. The petrosal branch (PB), the petrosquamous branch (PSB), and the posterior convexity branch (Post B) of the middle meningeal artery supply the SP3. C, Anterior oblique view of selective angiography of the middle meningeal artery during the embolization procedure shows a shunted pouch (arrows) that is located medial to the transverse-sigmoid junction. Multiple branches of the middle meningeal artery converge on the shunted pouch. A microcatheter is advanced into the shunted pouch with a transvenous approach. D, Fluoroscopic image after selective embolization shows a coil mass in the shunted pouch. Minimal shunt through the coil mass remains after selective transvenous embolization. E, Angiography during injection of diluted n-butyl 2-cyanoacrylate (33% n-BCA-lipiodol mixture) via the petrosquamous branch shows sufficient filling of the n-BCA into the residual part of the shunted pouch without migration into the main lumen of the sinus. F, Lateral view of right external carotid angiography after embolization shows marked regression of DAVFs with their disappearance at the transverse-sigmoid junction. Small residual AVFs were seen at the vertical portion of the sigmoid sinus (SP2) and the sigmoid-jugular junction (SP1). These residual shunted pouches were not treated because they seemed to be too small to catheterize and were supplied by dangerous feeders of stylomastoid branch and a petrosal branch of the middle meningeal artery. G, Frontal view of common carotid angiography at the venous phase shows that normal blood flow via the right transverse-sigmoid sinus is preserved. Arrows indicate staining of the paraganglioma at the carotid bifurcation.

Left transverse sigmoid DAVFs (type IIa) with 3 shunted venous pouches. Frontal (A) and lateral (B) views of the left external carotid angiography show DAVFs involving the left transverse-sigmoid sinuses. The DAVFs are fed by multiple branches of the external carotid artery and drain into the posterior condylar vein, the mastoid emissary vein, and the superior petrosal sinus with occlusion of the sigmoid sinus at the proximal end. Frontal view of right vertebral angiography (C) shows the DAVF fed by the posterior meningeal artery. D, Axial reformatted images of rotational angiography of the left external carotid artery show 3 shunted pouches, which are located dorsal to the vertical portion of the sigmoid sinus (SP1), at the transverse sigmoid junction (SP2), and inferior to the distal transverse sinus (SP3). The SP1, SP2, and SP3 are fed by the jugular branch (JB) and hypoglossal branch (HGB) of the ascending pharyngeal artery, the petrosquamous branch (PSB) of the middle meningeal artery, and the posterior convexity branches of the middle meningeal artery and the transosseous branches of the occipital artery, respectively. E, An axial reformatted image of rotational angiography of the right vertebral artery shows the posterior meningeal artery (PMA) also supplying the shunted pouch inferior to the distal portion of the transverse sinus (SP3). F, Selective venography of the shunted pouch (SP3) via a microcatheter (arrow) selectively introduced into the SP3 shows the separated venous pouch parallel to the transverse sinus. The shunted pouch was embolized with coils. G, Selective angiography with simultaneous injection via 2 microcatheters, one positioned at the petrosquamous branch of the middle meningeal artery and the other positioned at another shunted pouch of SP2, shows a shunted venous pouch at the transverse-sigmoid junction. The shunted pouch was also embolized with coils and glue. H, Lateral view of the right external carotid angiography after embolization shows marked regression of the DAVFs. A small part of the DAVFs remains with a shunted venous pouch (arrows) located dorsal to the sigmoid sinus (SP1), which was supplied by a hypoglossal branch (HGB) and a JB of the ascending pharyngeal artery. I, Right vertebral angiography during the venous phase shows coils placed parallel to the transverse sinus. Normal sinus flow of the transverse-sigmoid sinuses is preserved.

Left transvers sinus DAVFs (type IIa+b) with left sigmoid sinus occlusion. Frontal (A) and lateral (B and C) views of the left external carotid angiography show DAVFs diffusely involving the left transverse sinus. The DAVFs are fed by the left occipital artery and the convexity branch of the middle meningeal artery and drain retrogradely into the contralateral transverse sinus, the straight sinus, and the left temporal vein (vein of Labbé). D, Frontal view of the right external carotid artery shows DAVFs at the sinus confluence fed by multiple branches of the occipital artery. E, Axial reformatted images of rotational angiography of the left external carotid artery show shunted pouches (white arrows) that are located inferodorsally to the distal transverse sinus. The shunted pouches were fed by numerous transosseous branches of the occipital artery (TOB). F, Axial reformatted images of rotational angiography of the right external carotid artery show another shunted pouch (white arrows) that is located inferodorsally to the sinus confluence. The shunted pouches were fed by multiple TOBs. G, Selective venography via a microcatheter navigated through the occluded sigmoid sinus shows a shunted venous pouch inferior to the transverse sinus. Each shunted pouch was selectively catheterized and embolized with coils. Right (H) and left (I) external carotid angiography after selective transvenous embolization shows the disappearance of the DAVFs. J, Left internal carotid angiography during the venous phase 10 days after embolization shows coils placed inferior to the transverse sinus and preserved and reconstructed venous flow in the transverse-sigmoid sinus. Note the normalized venous flow of the vein of Labbé antegradely into the transverse sinus.

Right transverse sigmoid sinus DAVFs (type I) with a localized shunted venous pouch at the transverse-sigmoid junction. A, Right external carotid angiography shows DAVFs at the transverse-sigmoid junction. The DAVFs are fed by the right occipital artery, the posterior auricular artery, the posterior convexity branch, and the petrosal branch of the middle meningeal artery and drain antegradely into the sigmoid sinus. B, Axial reformatted images of DSA of the right external carotid artery show a shunted pouch (white arrow) that is located medial to the transverse-sigmoid junction. The shunted pouch is fed by the petrosal branch (PB) and the posterior convexity branch (Post B) of the middle meningeal artery, the posterior auricular artery (PAA), and the transosseous branches (TOB) of the occipital artery (OA). The AVFs disappeared following selective transvenous embolization (not shown).