Objective: There is limited evidence for mechanical thrombectomy in patients with basilar artery occlusion. Despite recanalization, there are several reports on poor outcomes. Therefore, we retrospectively evaluated the outcomes and examined the predictors of mechanical thrombectomy in patients with basilar artery occlusion.

Methods: We recruited 22 consecutive patients who had received mechanical thrombectomy for basilar artery occlusion with a direct aspiration first-pass technique at our hospital between January 2016 and April 2020. The subjects were divided into good (modified Rankin Scale [mRS] ≤2) and poor outcome groups (mRS ≥3) and compared with one another. We conducted ROC analysis to identify the cut-off value that revealed a statistically significant difference in the univariate analysis.

Results: Of the 22 patients, the average age ± standard deviation (SD), median pretreatment NIHSS (interquartile range [IQR]), and median pretreatment posterior circulation acute stroke progression early CT score (pc-ASPECTS) (IQR) were 76 ± 10 years, 21 (8–31), and 8 (5–9), respectively. The predictors that showed statistically significant differences in the univariate analysis were age, pretreatment NIHSS score, and pretreatment pc-ASPECTS. Based on the ROC analysis, age (area under the curve [AUC] of 0.782, cutoff <74, and P = 0.028), pretreatment pc-ASPECTS (AUC of 0.850, cutoff ≥7, and P = 0.006), and pretreatment NIHSS (AUC of 0.803, cutoff <19, and P = 0.018) were significant prognostic factors.

Conclusion: In this study, aged <74 years, pc-ASPECTS ≥7, and NIHSS <19 were significant prognostic factors in endovascular treatment for basilar artery occlusion with a direct aspiration first-pass technique.

Objective: To evaluate the efficacy and safety of interventional radiology (IVR) for aneurysmal subarachnoid hemorrhage (SAH) later than 3 days after onset.

Methods: A total of 71 patients between 2012 and 2017 who underwent endovascular coiling were divided into two groups according to the timing of treatment: Group E (treated within 3 days after onset) and group D (treated between 4 and 14 days after onset), and the outcomes between two groups were compared. A case-matched study was conducted to minimize the selection bias lying in this cohort.

Results: There were 56 (78.9%) and 15 (21.1%) patients in groups E and D, respectively. In group D, all patients arrived at the hospital later than 3 days after onset. The rates of patients with WFNS grade 1, 2, 3 and the presence of vasospasm upon the access route to the targeted aneurysm at the time of IVR were significantly higher in group D than in group E (93.3% vs 60.7%; p = 0.027, 33.3% vs 3.6%; p = 0.0037, respectively). There were no significant differences in the rate of intraprocedural complications, symptomatic vasospasm, delayed cerebral infarction due to vasospasm, retreatment, or modified Rankin Scale (mRS) at discharge. After propensity score matching, there were no significant differences in the outcomes between two groups.

Conclusion: Prompt coiling for patients with ruptured aneurysms who arrived later than 3 days after onset can be safely performed, even if they had vasospasm upon the access route.

Objective: To report our experience on a rare case of a ruptured aneurysm at the supracallosal portion (A4–A5) of the bihemispheric anterior cerebral artery (ACA), an ACA anomaly, and present that endovascular surgery was a good treatment even for peripheral cerebral aneurysm.

Case Presentation: A 53-year-old woman experienced a sudden onset of severe headache and vomiting. Plain CT scan revealed subarachnoid hemorrhage and hematoma in the supracallosal area. Cerebral angiography showed that the left pericallosal artery supplied blood to the bilateral parietal lobes through the bihemispheric artery. A saccular aneurysm was found at the supracallosal portion of the left bihemispheric ACA. Coil embolization of the cerebral aneurysm was performed completely.

Conclusion: Several reports have demonstrated an aneurysm with bihemispheric ACA, all treated by neck clipping. In this case, endovascular treatment for intracranial peripheral cerebral aneurysms becomes possible, and treatment indications are said to expand.

Objective: We report a case of a ruptured aneurysm at the posterior inferior temporal artery (PITA) of the posterior cerebral artery (PCA) treated by intra-aneurysmal coil embolization.

Case Presentation: A 93-year-old man presented with disturbance of consciousness. Angiography revealed a 3-mm aneurysm in the distal PITA of the left PCA. He was diagnosed with subarachnoid hemorrhage and intracerebral hemorrhage due to a ruptured aneurysm. This aneurysm was occluded by intra-aneurysmal coil embolization with preservation of the PITA.

Conclusion: Distal PITA aneurysm of the PCA is rare. Complete occlusion and preservation of the parent artery were achieved by intra-aneurysmal coil embolization, which may be an effective therapeutic option for such aneurysms.

Objective: We report a case of ruptured posterior cerebral artery (PCA) dissecting aneurysm treated with stent-assisted coil embolization in the acute phase of ruptured aneurysm.

Case Presentation: A 60-year-old woman presented with sudden onset of severe headache followed by unconsciousness. CT showed severe subarachnoid hemorrhage. Digital subtraction angiography showed a dissecting aneurysm at the P2 segment of the right PCA. Stent-assisted coil embolization was performed for the ruptured dissecting aneurysm. Since thrombus was observed in the stent, ozagrel was administered intravenously, and the thrombus gradually disappeared during the follow-up period. She was discharged without neurological deficit.

Conclusion: Parent artery occlusion is widely performed for acute ruptured PCA dissecting aneurysm, but reconstruction with stent-assisted coiling is considered to be an effective therapeutic strategy.

Objective: Superior petrosal sinus dural arteriovenous fistula (SPS-DAVF) is a rare subtype of intracranial DAVF that sometimes leads to hemorrhagic symptoms following deep venous drainage. Here we report the case of SPS-DAVF with retrograde venous reflux to the cerebellar vein. Preoperative contrast-enhanced MRI was a decisive factor in a safe and effective treatment.

Case Presentation: A 37-year-old woman was referred to our hospital with abnormal MRI findings, which was performed when she had a mild headache during her check-up. DSA revealed left-sided SPS-DAVF, which was diagnosed as Cognard type IIb. Both CTA and DSA could not detect the whole SPS but only the shunt pouch. Using contrast-enhanced MRI, we were able to visualize the presence of the SPS and its continuity within the shunt pouch. 3D-T1 turbo spin echo (SPACE) showed a low-intensity area in the SPS, which was not seen in the 3D-T1 fast field echo (FFE). During the procedure, there was a point where it was difficult to advance the microcatheter, which coincided with the low-intensity area. We achieved effective transvenous embolization from the occluded venous access by devising a surgical technique.

Conclusion: In addition to the contrast-enhanced 3D-T1 FFE, 3D-T1 SPACE might provide beneficial information for endovascular therapy in the evaluation of venous sinuses, which could not be detected by standard examinations.

Objective: The vessel compression at the root entry zone (REZ) of trigeminal nerve is a common cause of trigeminal neuralgia (TN). We report a rare case of TN caused by dural arteriovenous fistula (DAVF) of the transverse-sigmoid sinus without vessel compression at REZ.

Case Presentation: A 45-year-old woman presented with right side tinnitus and was diagnosed as a DAVF of the right transverse-sigmoid sinus (Borden Type I). After that, the facial pain in the right maxillary nerve area appeared and was getting worse. DSA revealed an enlargement of the artery of foramen rotundum (AFR) as one of the feeding arteries. MRI revealed no evidence of vascular compression at REZ. The patient was treated with transarterial embolization (TAE) with Onyx via the branches of the middle meningeal artery (MMA) and occipital artery (OA). The AFR decreased in size and the facial pain was improved. However, the DAVF and the facial pain were recurred. Finally, the DAVF was completely embolized with transvenous embolization (TVE). During 1-year follow-up period, the patient remained free of pain without recurrence.

Conclusion: The compression of the maxillary nerve by the AFR might result in TN, because the pain diminished after shrinkage of the AFR by the endovascular treatment.

Objective: We report a case of hemorrhagic complication after mechanical thrombectomy (MT) for internal carotid artery (ICA) occlusion with twig-like middle cerebral artery (MCA).

Case Presentation: A 75-year-old man was admitted to our hospital with ICA occlusion. Recanalization was achieved by a direct aspiration first pass technique (ADAPT). The peripheral MCA was twig-like, but operators thought that a thrombus remained in the MCA first segment. The procedure was continued and suspended with perforation of the microguidewire.

Conclusion: When performing MT for large vessel occlusion (LVO) with twig-like MCA, it is difficult to proceed a device to the periphery and there is a risk of hemorrhage.

Objective: Currently, there are no established approaches for removal of devices, such as stents, which sometimes become difficult to recover during endovascular treatment. We report a new method to successfully remove a stent that has become snagged during thrombus removal.

Case Presentation: An 82-year-old female who had undergone a mitral valve annuloplasty developed sudden aphasia, right hemiplegia, and right unilateral spatial neglect on postoperative day 10. Cranial MRI indicated occlusion of the horizontal segment of the left middle cerebral artery. During mechanical thrombectomy, a vasospasm snagged the stent, and re-sheathing attempts failed repeatedly. We wedged the microcatheter into the spasm site and slowly injected a solution containing 1 cc of nicardipine, 2 cc of contrast medium, and 2 cc of heparin in normal saline intra-arterially. After several minutes, we retracted the Trevo wire slightly and easily removed the stent. The thrombus adhered to the retrieved stent. Post-retrieval imaging showed that the branch was completely recanalized.

Conclusion: In cases wherein a microwire or stent retriever becomes difficult to remove, we propose switching to a microcatheter with a sufficient diameter to allow vasodilator injection. If the microcatheter is difficult to remove, our method can be utilized by severing the hub, inserting a larger-bore catheter, and injecting vasodilators. Adding contrast medium to the intra-arterial injectate allows visualization of whether the solution has reached the spasm site. Furthermore, by injecting the solution through the wedged catheter, pooling of the solution at the spasm site can be confirmed.