Background: Staged angioplasty (SAP) for cervical carotid artery stenosis is useful in preventing cerebral hyperperfusion syndrome (CHS) following a carotid revascularization procedure. However, expansion failure due to elastic recoil (ER) occurs often. Herein, we investigated the frequency and clinical significance of ER.

Methods: Among the 49 SAP cases, the extent of ER was quantitatively defined as a minimal lumen diameter (MLD) loss of >10% between the time immediately after the angioplasty and 15 minutes later. A relationship between ER and restenosis (NASCET ≥70%) during CAS as a second-stage surgical option and severe ER (>30% indicating restenosis) and its risk factors were also evaluated.

Results: The MLD improved from 0.7±0.3 mm before performing angioplasty to 2±0.5 mm after the angioplasty. ER was recognized in 41 cases (84%), with 5 cases eventually requiring urgent CAS. On the third postoperative day, urgent CAS was required in one case due to the deterioration of hemiparesis. However, CHS did not occur in all cases. The lumen loss was significantly associated with restenosis progression in 7 cases (p=0.01). Regarding severe ER (lumen loss >30%) in 28 cases (57%), patients aged >75 years (p=0.01), eccentric stenosis (p=0.02), and vessel calcification angle >180° (p=0.04) were found to be statistically significant risk factors.

Conclusions: Restenosis due to ER tends to occur in elderly patients with eccentric calcified stenosis. In such cases, surgeons should perform CAS as early as possible.

Objective: Insurance coverage for carotid artery stent CASPER Rx began in September 2020. We have previously reported the usefulness of 3D-RA immediately after carotid artery stenting and at follow-up after implantation to evaluate the stent appearance and stent lumen.

Methods: Based on the results of the study on the optimal dilution concentration of contrast agent in the phantom study, images of 18 cases (11 immediately after stenting and 7 follow-up cases) that underwent 3D-RA between November 2021 and April 2022 were examined retrospectively.

Results: In the phantom study, the three differences in contrast medium concentration between vessel, stent, and background were obtained at 7x to 9x dilution. In clinical practice, however, the optimum contrast medium dilution concentration is higher than this because of the effect of blood flow. In the present study, three differences in vessel, stent, and background concentrations were obtained at 4x dilution.

Conclusion: The optimal contrast dilution concentration of 3D-RA for CASPER Rx was a 4-fold dilution concentration when the injection rate of the contrast medium was 3.5 mL/sec.

Objective: We report a case of mechanical thrombectomy for acute occlusion of the intracranial internal carotid artery with two unruptured cerebral aneurysms.

Case Presentation: A 74-year-old woman developed dysarthria and left hemiparesis at wake-up, last seen normal 9 hours ago. She had a score of 20 points on the National Institutes of Health Stroke Scale (NIHSS). Three-dimensional reconstruction of the cerebral angiogram revealed a right internal carotid artery occlusion with right internal carotid-posterior communicating artery aneurysm. She was treated using a direct aspiration first pass technique (ADAPT), resulting in thrombolysis in cerebral infarction (TICI) grade 3. Postoperatively, the patient was transferred to a recovery hospital one month after mechanical thrombectomy due to residual left hemiparesis.

Conclusion: Appropriate treatment strategy is necessary for revascularization of patients with cerebral aneurysm in the occluded vessel.

Objective: In this report, we present a case of a superior sagittal sinus (SSS) dural arteriovenous fistula accompanied by papillary edema and visual impairment. Although repeated intervention finally obliterated the arteriovenous shunt, visual impairment progressed and persisted.

Case Presentation: A 52-year-old man presented with rapidly progressive bilateral visual impairment. Evaluation revealed an SSS dural arteriovenous fistula with multiple shunts and SSS stenosis. We performed transarterial embolization using N-butyl-2-cyanoacrylate followed by transarterial Onyx embolization. The arteriovenous shunt was almost obstructed; however, visual function did not improve. Finally, we performed SSS packing to prevent intracranial hemorrhage, as the SSS was isolated, and we detected cortical venous reflux. Both the arteriovenous shunt and cortical venous reflux were completely resolved; however, visual acuity was still not restored.

Conclusion: Venous angioplasty with or without stenting and/or cerebrospinal fluid shunting should be considered if early obliteration of arteriovenous shunts fails to decrease intracranial pressure sufficiently in patients with an SSS dural arteriovenous fistula accompanied by papillary edema.

Objective: An organized hematoma is a benign mass lesion that easily bleeds and frequently occurs in the maxillary sinus. The first-line treatment is usually surgical removal of the hematoma. Preoperative embolization is sometimes performed to avoid intraoperative heavy bleeding. We report the case of an elderly patient with high surgical risk who underwent vascular embolization alone that resulted in a good hemostatic effect and reduction of the mass.

Case Presentation: An 87-year-old man had repeated severe epistaxis requiring blood transfusion from an organized hematoma of the left maxillary sinus. The left sphenopalatine artery was the feeding artery of the lesion, and it was embolized with n-butyl cyanoacrylate. Four months postoperatively, epistaxis stopped and a computed tomography scan showed shrinkage of the mass.

Conclusion: Embolization alone for an organized hematoma is a treatment option in patients with no symptoms other than epistaxis and high surgical risk.

Objective: Aneurysms of the common carotid artery are associated with cerebral infarction and cervical pulsatile mass. Recently, endovascular treatment has been often chosen for anatomical reasons; however, the optimal treatment method remains to be established. We report a case in which a common carotid artery aneurysm close to the aortic arch was treated by stent-assisted coil embolization with stabilization of a guiding catheter and a microcatheter.

Case Presentation: A 74-year-old female patient underwent stent-assisted coil embolization for a left common carotid artery aneurysm with a maximum diameter of 19 mm. The aneurysm was located in the proximal portion of the left common carotid artery, with a steep bifurcation angle from the aorta and proximal bending. An 8F Neuro-EBU catheter was placed at the origin of the left common carotid artery, and a 6F catheter was used for catheter stabilization. The balloon of the Carotid Guardwire PS was dilated in the external carotid artery, and a 5F Envoy catheter was placed in the aneurysm and stabilized. Then a microcatheter was inserted into the aneurysm. A self-expandable stent for the carotid artery was partially deployed, and the Semi-jailing technique was used for coil embolization.

Conclusion: Stent-assisted coil embolization was performed for a common carotid artery aneurysm close to the aortic arch. The study findings indicate the need for catheter support for the safe treatment of an aneurysm.