PMC8769469_01
MRI revealed a left pontine mass exhibiting a high signal intensity on T2-weighted (A) and FLAIR (C) imaging, low intensity on T1-weighted imaging (B), and enhancement demarcated by the pontine raphe on gadolinium T1-weighted imaging (D). T2-weighted and FLAIR imaging showed high signal intensity in the medial left temporal lobe. MRA showed a dilated vein of Rosenthal on the left (arrowheads) (E and F).
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F1
T1-weighted imaging (Gd-T1WI) showed a contrast-enhancing left pontine mass lesion demarcated by the pontine raphe and a dilated vein of Rosenthal on the left. T2-weighted imaging (T2WI) and FLAIR imaging showed a hyperintense region in the medial left temporal lobe that was considered brain edema (Fig. 1).
Anteroposterior (A, C, and E) and lateral (B, D, and F) views of the left external carotid artery show a dural arteriovenous fistula at the transverse-sigmoid junction with an isolated sinus. The posterior branch of the middle meningeal artery and occipital artery were feeding arteries. Retrograde venous flow to the vein of Rosenthal and vein of the great horizontal fissure was confirmed. Anteroposterior (G) and lateral (H) views of the right external carotid artery showed arterial supply from the right occipital artery.
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F2
Therefore, cerebral angiography was performed, which revealed left TS dAVF with an isolated sinus that was supplied by the left middle meningeal artery (MMA) and both occipital arteries (Fig. 2).
Embolization of the left occipital (A and B) and left middle meningeal arteries (C-E). Angiography after transarterial embolization (F) and before transvenous embolization (TVE) (G), insertion of microcatheter into the isolated sinus (H), coil embolization of the isolated sinus (arrowheads) (I), angiography after TVE (J and K), and CT showing coils occluding the isolated sinus (arrow) (L).
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F3
Transarterial embolization (TAE) was performed under general anesthesia to reduce shunt flow (Fig. 3). After 3 days, transvenous embolization (TVE) was performed under general anesthesia (Fig. 3).
MRI 3 months after treatment showed normal findings in the left pons (A-D). Cerebral angiography 6 months after treatment showed the disappearance of shunt flow (E and F).
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F4
Brain MRI after 3 months showed improvement and shunt flow had completely disappeared on cerebral angiography after 6 months (Fig. 4).