Objective: Selective transvenous embolization (sTVE) is an effective technique for treating dural arteriovenous fistulas (DAVFs); however, selective catheterization into the shunted pouch is often difficult due to the acute angle of the access route between the target pouch and dural sinus. We present our initial experience using a steerable microcatheter (SM) to manually control the tip angle for selective catheterization and sTVE of DAVFs.

Methods: Thirteen consecutive cases of DAVFs and 16 procedures that involved sTVE using SM between October 2016 and October 2018 were reviewed. SMs were used for selective catheterization of shunted venous pouches and/or the affected sinus and coil embolization. We evaluated the maneuverability of the SM, the success of selective catheterization into the target lesions, and the results of endovascular treatments.

Results: Endovascular procedures were performed in a single session in 10 cases and in two staged sessions in 3 cases. There was no difficulty in maneuverability of the SM. Successful selective catheterization was achieved in 26 of 27 target lesions. Immediately after embolization, angiography showed complete occlusion in 10 cases and marked reduction in 3 cases. During 40.9 months of mean follow-up, 12 cases showed complete occlusion and one case showed a small residual shunt on MRI. Procedure-related complications of spontaneous thrombosis of the affected sinus were observed in one case. There were no cases of recurrence or exacerbation during follow-up.

Conclusion: SM is useful for selective catheterization for target lesions during sTVE of DAVFs.

Objective: We aimed to evaluate the efficacy of the “improved motion-sensitized driven-equilibrium (iMSDE)”-prepared T1-weighted black blood (T1-BB) MRI for monitoring treatment effect with a flow diverter (FD) for cerebral aneurysms.

Methods: Following the exclusion of concomitant coiling and retreatment cases from 60 consecutive cases of cerebral aneurysms treated with FDs at our institution, 32 with imaging data were included in the analysis. Detectability of residual blood flow within the aneurysms was validated as follows: 1) comparison of MRI sequences (iMSDE-prepared T1-BB images, T1-weighted images [ T1WI], and time-of-flight [ TOF]-MRA) in cases of incompletely occluded aneurysms and 2) comparison of angiography and MRI sequences in the same period.

Results: 1) The probability of diagnosing intra-aneurysmal blood flow was significantly higher with iMSDE-prepared T1-BB (iMSDE-prepared T1-BB vs. T1WI, p <0.001; iMSDE-prepared T1-BB vs. TOF-MRA, p <0.001). 2) The diagnostic accuracy of residual aneurysmal blood flow was significantly higher with iMSDE-prepared T1-BB than that with T1WI (p = 0.032). Furthermore, in cases of incomplete occlusion, the probability of detecting intra-aneurysmal blood flow was significantly higher with iMSDE-prepared T1-BB (iMSDE-prepared T1-BB vs. T1WI, p <0.001; iMSDE-prepared T1-BB vs. TOF-MRA, p = 0.023).

Conclusion: Our results demonstrated that iMSDE-prepared T1-BB could help distinguish between blood flow and thrombus within the aneurysms after FD treatment, especially in the early stages of FD treatment.

Objective: Extracranial internal carotid artery aneurysms (ECAAs) are rare. We herein describe a case of overlapped stenting with two double-layer micromesh stents for a giant ECAA.

Case Presentation: A 73-year-old man presented to our hospital with an enlarged right posterior cervical mass. A right internal carotid artery (ICA) angiogram revealed a giant aneurysm of 50 × 60 mm. We chose a carotid double-layer micromesh stent for stenting. With the patient under general anesthesia, the first double-layer micromesh stent (CASPER Rx, 10 × 30 mm; Terumo, Tokyo, Japan) was deployed between the ICA distal to the aneurysm and the common carotid artery (CCA). The second stent was also deployed from a site more proximal than the first one. Ten coils were then placed from a microcatheter that had been placed in the aneurysm. A right CCA angiogram after the procedure revealed a flow-diversion effect for the aneurysm. The patient was discharged with no complications. At the 6-month follow-up angiogram, blood flow into the aneurysm had completely disappeared.

Conclusion: A flow-diversion effect using overlapped double-layer micromesh stents can result in thrombosis and healing of giant ECAAs.

Objective: CASPER Rx stent (Terumo, Tokyo, Japan) is one of the dual-layer micromesh stents for carotid artery stenosis. Although it is expected to be safe and efficacious even for vulnerable plaque, we report a case of in-stent occlusion 2 weeks after stenting with CASPER Rx stent.

Case Presentation: The patient was a 78-year-old man with a symptomatic, severely stenosed lesion of the cervical internal carotid artery (ICA). He had an unstable plaque and underwent carotid artery stenting with the CASPER Rx stent. There were no problems with the procedure or the patient’s subsequent course, and he was discharged home 1 week after the procedure. However, on postoperative day 14, the patient had a transit ischemic attack and imaging showed acute occlusion due to thrombus in the stent and in the distal part of the ICA. Mechanical thrombectomy was performed and good recanalization was achieved, but postoperative cerebral infarction was observed and the patient was transferred to other hospital with modified Rankin Scale 2.

Conclusion: We experienced a case of in-stent occlusion 2 weeks after stenting with the CASPER Rx stent.