PMC8769384_01
Preoperative MR angiography, brain CT, DSA. MR angiography revealed CS-dAVF accompanied by an expanded left SOV (arrowheads) and left SMCV (arrow) (A). Brain CT showed a small parenchymal hematoma in the left temporal lobe (B). The left SOV was not depicted by MR angiography (C). Three-dimensional DSA of the left internal carotid artery showed a 7-mm broad-neck uAN at the left MCA M1M2 junction (arrow) (D). A right external carotid angiogram A-P view and lateral view (E, F). A left external carotid angiogram (G: A-P view, H: lateral view). A bilateral external carotid angiogram showed right CS-dAVF. CS-dAVF: cavernous sinus dural arteriovenous fistula, CT: computed tomography, DSA: digital subtraction angiography, MCA: middle cerebral artery, MR: magnetic resonance, SOV: superior orbital vein, uAN: unruptured aneurysm.
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F1
Magnetic resonance imaging (MRI) revealed CS-dAVF accompanied by an expanded left SOV and left SMCV as well as uAN of the left MCA (Fig. 1A). At 1 week after admission, computed tomography (CT) showed a small parenchymal hematoma in the left temporal lobe (Fig. 1B). The left SOV was not depicted by MRI at that time (Fig. 1C). Digital subtraction angiography (DSA) showed that the bilateral ascending pharyngeal arteries (APAs) were the main feeders (Fig. 1E-1H). There was a shunting point behind the right CS draining to the left CS through the intercavernous sinus (ICS) (Fig. 1E and 1G). Left internal carotid angiography also showed a broad-neck aneurysm (7 mm) at the MCA of the M1/M2 junction (Fig. 1D).
Intraoperative photos (cannulation of the SMCV). We performed left frontotemporal craniotomy and exposed the SMCV (A). The SMCV was sufficiently peeled from the brain surface and secured with silk thread (B). After closing the proximal and distal part of the SMCV with a temporary clip, the SMCV was punctured with a needle. The sheath was inserted into the SMCV and fixed with silk thread under a microscope (C). A 50-cm extension tube was connected to the sheath to separate the portion receiving catheter surgery from the open surgery part (D). SMCV: superficial middle cerebral vein.
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We performed left frontotemporal craniotomy and exposed the left SMCV (Fig. 2A) after opening the Sylvian fissure under general anesthesia. After clamping the proximal and distal SMCV with a temporary clip, the SMCV was punctured with a needle (Fig. 2B). The sheath (4-Fr micropuncture introducer kit; Cook, Bloomington, IN, USA) was inserted into the SMCV and advanced into the sphenoparietal sinus before ultimately being fixed with silk thread (Fig. 2C). To reduce the radiation exposure to the surgeon, a 50-cm extension tube (Safido, 50 cm, 2.1 mm; TERUMO, Tokyo, Japan) was connected to Y connector (Gateway Plus Y Adapter; Boston Scientific, Marlborough, MA, USA) and perfuse heparinized saline to separate the catheter from the surgical field (Fig. 2D).
Endovascular treatment. The microcatheter was induced to the shunting point behind the right CS through the left CS and ICS (A, B). After sinus packing by coil embolization from the right to left CS (C: A-P view, D: lateral view). Post-transcranial sinus packing left common carotid angiogram (E: A-P view, F: lateral view). CS: cavernous sinus, ICS: intercavernous sinus.
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We then shifted to endovascular treatment (Fig. 3A). The microcatheter was barely able to be induced to the shunting point located behind the right CS through the ICS via the left CS (Fig. 3B) without heparinization. The left CS was then embolized with four coils (Fig. 3C). The microcatheter was also induced to the left superior petrosal sinus (SPS), which was embolized with four coils (Fig. 3D). After confirming the disappearance of the shunt, the endovascular treatment was finished (Fig. 3E and 3F).
A right external carotid angiogram (A: A-P view, B: lateral view). A left common carotid angiogram (C: A-P view, D: lateral view). A skull-XP after coil embolization and neck clipping (E: A-P view, F: lateral view).
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Finally, the CS-dAVF and left MCA uAN were no longer visible on intraoperative DSA (Fig. 4A-4D).