The anterior condylar arteriovenous fistula (AC-AVF) is a relatively rare AVF that affects the vasculatures adjacent to the hypoglossal canal. We aimed to discuss the etiology and definition of the AC-AVF from the viewpoint of the osseous venous anatomy. Our recent study, which used modern imaging technology (CT digital subtraction venography and cone beam CT reconstructed from 3D rotational angiography), elucidated the intraosseous venous anatomy in this region and the precise fistulous locations of AC-AVFs. Those findings suggest that the AC-AVF is a group of “osseous” AVF that involves the anterior condylar vein and jugular tubercle venous complex (JTVC), and the osseous veins connected to them. The AC-AVF develops in osseous veins adjacent to the hypoglossal canal, and it is one of the most common subtypes of osseous AVFs. The angioarchitectures and etiology of AC-AVFs discussed herein are essential to understand this clinical entity.

Objective: A direct aspiration technique using a 5MAX ACE catheter (Penumbra, Alameda, CA, USA) has been reported. However, recanalization has not been achieved in all cases with this technique alone. Additionally, Japan has a rapidly aging society, and differences in the condition of vessels, because of aging, can limit the approach of revascularization devices to the thrombus. We evaluated the accessibility of the 5MAX ACE (0.060-inch inner diameter) over the clinoid segment of the internal carotid artery (ICA).

Methods: We conducted a retrospective and cross-sectional study of 28 patients who received intraarterial treatment for acute ischemic stroke between October 2014 and October 2016. We recorded the maximum distal arrival point of the distal edge of the 5MAX ACE during the procedure before the stent retriever was retrieved.

Results: In 5 of the 28 patients, the distal edge of the 5MAX ACE catheter did not advance over the clinoid segment of the ICA. The mean age of patients for whom the 5MAX ACE catheter failed to advance over the clinoid segment of the ICA was significantly higher (non-advancement: 85 ± 3 years) than that of patients with advancement (76 ± 9 years, Mann–Whitney U-test: P = 0.04).

Conclusion: Advanced age may limit successful revascularization using only a direct aspiration technique with the 5MAX ACE without a stent or balloon anchoring technique for lesions at the terminal portion of the ICA and more distal arteries, which suggests that different devices or approaches may be needed for clot removal.

Objective: The purpose of this study is to retrospectively assess the differences between spinal dural arteriovenous fistulas (SDAVFs) and spinal epidural arteriovenous fistulas (SEAVFs).

Methods: Subjects consisted of 18 patients with SDAVFs and 7 with SEAVFs admitted to our department between January 2007 and December 2017 exhibiting intradural drainage of shunt flow. Patient background, lesion characteristics, and treatment/follow-up results were compared.

Results: Of the seven patients in the SEAVF group, six patients (86%) had been misdiagnosed with SDAVFs at the time of treatment. The rates of patients with a history of spinal surgery, lumbar vertebral lesions, involvement of a dorsal somatic branch (DSB), involvement of multiple segmental arteries, or involvement of bilateral segmental arteries were significantly higher in the SEAVF group. As for post-treatment course, there were significant difference in the recurrence rate after endovascular treatment (SDAVF group: 6%, SEAVF group: 50%, respectively, p < 0.05).

Conclusion: Endovascular treatment may not be effective for SEAVFs if they are misdiagnosed as SDAVFs, and they may recur. For optimal treatment, accurate assessment of the angioarchitecture with the latest diagnostic imaging method may be necessary.

Objective: Occasions to administer endovascular treatment to the elderly have increased, for which rapid and safe guiding catheter (GC) placement even in a lesion with severe arteriosclerosis is required. We investigated an index to easily evaluate the degree of difficulty before treatment.

Methods: In all, 83 consecutive patients who received carotid artery stenting (CAS) through the transfemoral approach at our institution between May 2010 and December 2016 were divided into those in whom GC could be placed using the JB2-type inner catheter (IC) (JB2 group) and those who required the Simmons type or Goose neck snare (SM/GS group). Vascular anatomy of the cervicothoracic region was evaluated and an index to select IC was investigated.

Results: The JB2 and SM/GS groups consisted of 68 and 15 patients, respectively. The distributions of the following five items were different between the two groups: The level of the origin of the selected artery from the lesser curvature of the aortic arch, aorta type, tortuosity of the common carotid artery, selected artery, and location of the lesion. On decision tree analysis of these factors, a flowchart was prepared in which a lower level of the origin of the selected artery than the level of the lesser curvature of the aortic arch was the first layer.

Conclusion: IC selection can be more accurately evaluated based on whether the level of the origin of the selected artery is lower than the level of the lesser curvature of the aortic arch compared with evaluation of the aorta type III.

Objective: The purpose of this study was to provide an update on recent developments in the diagnosis and treatment of arteriovenous fistulas at the craniocervical junction (CCJ AVFs).

Methods: Associated literature published between 2009 and 2018 on the PubMed database was reviewed.

Results: The systematic review identified 97 lesions in 92 cases of CCJ AVFs. These lesions were divided into three groups according to their angioarchitecture: 56 lesions of dural AVFs, 34 of intradural AVFs, and 7 of extradural AVFs. Clinical features, neuroimaging findings, treatments, and outcomes were compared among the three groups. Cases of dural AVFs were commonly associated with myelopathy and/or brainstem dysfunction due to venous congestion in the spinal cord (38%) and/or brainstem (21%). Cases of intradural AVFs had a more complex angioarchitecture than those of dural AVFs and were associated with a hemorrhagic presentation (83%). Of the 34 intradural AVFs, 25 lesions (74%) had a feeder aneurysm (n = 20) or varix (n = 5). The development of the aneurysm/varix may be attributed to hemodynamic and flow-related phenomena. The surgical obliteration of the intradural drainer and/or feeder was effective in most cases of dural and intradural AVFs. Endovascular embolization may be more effective in cases of extradural AVFs than in those of dural or intradural AVFs. No permanent neurologic complications occurred in 80 cases treated by surgery; however, brain infarction occurred in 2 (9%) of 22 cases treated by endovascular embolization. Good recovery was more frequently achieved in cases of intradural (79%) and extradural AVFs (100%) than in those of dural AVFs (61%) because cases with hemorrhagic presentation had fewer permanent neurologic deficits than those with venous congestion.

Conclusion: A differential diagnosis among dural, intradural, and extradural AVFs is important because clinical features, neuroimaging findings, and treatment outcomes markedly differ among the three groups.

Objective: We report a very rare case of dural arteriovenous fistula (DAVF) involving the inferior petroclival vein (IPCV).

Case Presentation: The patient was a 77-year-old woman. She suffered from right ophthalmalgia, pulsatile tinnitus, blepharedema, and chemosis, as well as right ptosis and diplopia (right oculomotor nerve palsy). Our imaging examinations demonstrated DAVF involving the IPCV. Since the proximal side of the right inferior petrosal sinus (IPS) was obstructed, the main venous drainage flow refluxed retrogradely from the IPS to the cavernous sinus (CS). Therefore, her clinical symptoms were similar to those of CS-DAVF. We successfully performed transvenous coil embolization (TVE) in the IPCV and IPS.

Conclusion: We experienced a very rare case of DAVF involving the IPCV. We believe that it is important in each case to understand the 3D vascular anatomy by making full use of 3D-DSA and other modalities to accurately identify the shunt point and venous drainage structure.

Objective: The flow diverter (FD) was developed as a new approach for treating aneurysms. However, FD embolization requires high technical skills and is challenging when the access to the aneurysm is difficult and when sufficient force cannot be transmitted to the catheter because of severe vascular tortuosity. For FD embolization, when a transfemoral approach is too difficult, we perform direct puncture of the common carotid artery (CCA) under direct visualization by making a small incision. Herein, we report our experience using this approach.

Case Presentation: We present a case of an 80-year-old woman with an unruptured aneurysm on the right internal carotid artery (ICA) treated by FD embolization in conjunction with coil embolization. We considered that access to the aneurysm would be challenging, with limited catheter maneuverability because of severe tortuosity of the bilateral femoral arteries and the region from the right CCA to the ICA. Thus, we decided to access the aneurysm by direct puncture of the right CCA. The aneurysm was easily accessed using this approach, and a stable procedure was completed by placing a sheath with a detachable hemostasis valve and then switching the hemostasis valve to a Y-connector on the sheath. As good catheter control was obtained despite the vascular tortuosity, the Pipeline Flex could be deployed and placed at the appropriate position.

Conclusion: Direct puncture of the CCA under direct visualization for FD embolization is useful when access to the aneurysm is challenging and when catheter maneuverability decreases because of severe tortuosity.