PMC4533415_01
Case 1 A: The patient's initial magnetic resonance imaging T2-weighted image demonstrated a small hyperintensity abnormal lesion in the right frontal lobe (closed arrow). B: Lateral view of right carotid injection (venous phase) showing sinus occlusion in the middle of the superior sagittal sinus (open arrow). C, D: The same injection at 2 weeks after local fibrinolysis using urokinase demonstrating remaining occlusion of the superior sagittal sinus. However, no dural arteriovenous fistula was present at this point. Note that a cortical venous occlusion is indicated by the closed arrows (D).
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F1
His magnetic resonance (MR) imaging revealed an abnormal area of hyperintensity in the right frontal lobe (Fig. 1A). After confirmation of an superior sagittal sinus (SSS) thrombosis in the patient's emergent angiogram (Fig. 1B), a microcatheter was advanced to the SSS via his femoral vein for local intravenous fibrinolysis. The 2-week follow-up angiogram showed residual SSS occlusion but no AVF at this point (Fig. 1C, D).
Case 1 Ten-month follow-up right carotid injection, anterior view (A), right oblique view (B), and lateral view (C, D) showing dural arteriovenous fistula (arrows) supplied by the middle meningeal artery (white dotted arrowhead), superior temporal artery and anterior cerebral artery (white arrowhead) with drainage to the Rolandic vein connecting to the superficial Sylvian vein (black arrowhead). Dotted arrows show faint contrast of thrombosed cortical veins (D). Note that the posterior parietal artery never participated in the shunt at this point.
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F2
However, the patient's 10-month follow-up angiogram revealed an asymptomatic dural AVF in the right side, arising from the middle meningeal artery, superficial temporal artery, and anterior cerebral artery, with drainage to the Rolandic vein and two other branches that were observed on the initial angiogram as being thrombosed (Fig. 2).
Case 1 Two-year follow-up angiogram after the superior sagittal sinus thrombosis (A-G): right internal carotid injection showing that, in addition to the fistula of the parietal cortex, another fistula emerged from the ipsilateral Sylvian fissure, arising from the M3-4 portion of the posterior parietal artery with drainage to the previously thrombosed cortical vein shown in Figs. 1D and 2D. Irregularity of the vessel was consistent with the residual thrombosis in the lumen of this vein (dotted arrows). This draining vein finally connected with the Rolandic vein (black arrowhead). The initial shunt from the anterior cerebral artery was barely recognized (A-C). However, the shunt of the initial arteriovenous (AV) fistula was considerably reduced, as the external carotid artery no longer contributed to this fistula (D). E-G: Anterior oblique view series of right internal carotid injection confirmed this new pial AV fistula arising from the middle cerebral artery. The fistulous point was indicated (long arrows) with drainage to the previously thrombosed cortical vein (dotted arrows) connecting to the Sylvian vein (black arrowheads).
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Furthermore, 2 years after the SSS thrombosis, angio-gram revealed a pial AVF in the right Sylvian fissure, supplied by the posterior parietal artery with drainage to the cortical vein leading to the Rolandic vein (Fig. 3).
Case 1 Twelve years later, the patient was transferred to the local hospital when he had severe headache and motor dysfunction in his left arm and leg. His computed tomography scan demonstrated intracerebral hemorrhage in the right frontal lobe (A). The lateral view of the right carotid injection confirmed the lesion (B: black arrowhead), in which the de novo draining vein arising from the corner of the main draining vein was found (B, C: black arrows). The patient underwent surgery to eliminate the fistula at the acute stage. Postoperative angiogram confirmed no presence of the fistula (D).
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He was brought to the hospital by ambulance, and his CT scan demonstrated intracerebral hemorrhage in the right frontal lobe (Fig. 4A). An angiogram confirmed the development of a pial AVF and disappearance of the initial dural AVF (Fig. 4B, C).
Angiographical scheme of Case 1. A: Anterior half of superior sagittal sinus and part of the cortical vein are thrombosed at the time of onset. B: Ten months after onset, a de novo dural AVF arose from the dural and pial arteries with drainage to the cortical vein. C: Two years after onset, another pial AVF occurred, while the initial dural AVF became a low-flow shunt. D: When the patient ultimately bled in the frontal lobe 12 years after the onset, the shunt flow of the pial AVF increased with the de novo draining vein arising from the main draining vein, while the dural AVF disappeared. AVF: arteriovenous fistula.
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Figure 5 summarizes the chronological course of the angiographical findings.
PMC4533415_02
Case 2: Preoperative left external carotid injection, anterior view (A, B) and lateral view (C, D) demonstrating dural arteriovenous (AV) fistula arising from the middle meningeal artery (white arrowhead) and superficial temporal artery with drainage to the possibly thrombosed Rolandic vein (black arrowhead) connecting with the superficial Sylvian vein. In addition, the second dural AV fistula (long black arrow) involving the sigmoid sinus with anterograde drainage coexsisted, as shown by the superselective occipital artery injection (E). A sinus thrombosis involving the superior sagittal sinus and the sigmoid sinus was found (B).
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Angiography on admission demonstrated two dural AVFs (Fig. 6).
Case 2 A, B: No arteriovenous (AV) fistula was found at the time of the preoperative left internal carotid injection. Note the corkscrew appearance of the cortical veins due to the superior sagittal sinus thrombosis at the venous phase (B). Angiogram after embolization and craniotomy (C-F). Anterior view of the left carotid artery injection revealing a de novo pial AV fistula supplied by the central artery (white arrows) (C). Lateral view of the left carotid injection showing that the new fistula with drainage (white arrows) was apparently distinct from the previous fistula, in a comparison with the location and shape of the draining cortical vein (D, E). The external carotid artery system was not attributed to this new fistula (F).
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A 1-month follow-up angiogram showed that the previous fistula in the parietal cortex had been completely obliterated (Fig. 7A, B). However, a de novo pial AVF, which was not identified before the surgery, was found (Fig. 7C-F).
Scheme of Case 2. A: Posterior half of superior sagittal sinus and cortical vein are thrombosed. Dural AVF supplied by external carotid arteries is present. B: Initial dural AVF is obliterated by transarterial embolization and surgical excision; however, de novo pial AVF emerges adjacent to the initial lesion. AVF: arteriovenous fistula.
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Figure 8 summarizes the chronological course of the patient's angiographical findings.