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.

We report 2 cases with subarachnoid hemorrhage (SAH) secondary to ruptured bloodblister aneurysms (BBAs) originating from the anterior wall of the internal carotid artery (ICA). Case 1: A 56-year-old man was transferred to our hospital with disturbed consciousness following a severe headache. Computed tomography (CT) showed diffuse subarachnoid hemorrhage, and cerebral angiography demonstrated a BBA originating from the anterior wall of the left ICA. We performed left ICA trapping with a high-flow bypass. His postoperative course was uneventful, and he was discharged without any neurological deficits. Case 2: A 49-year-old man was transferred to our hospital with disturbed consciousness. Although CT showed diffuse SAH, using cerebral angiography, we could not identify any aneurysms. CT repeated 16 days after admission revealed a BBA originating from his right ICA. We decided to perform direct neck clipping because we could identify the neck of the aneurysm. Direct neck clipping of the aneurysm was performed without any complications. The patient was discharged without neurological deficits. Although the treatment of BBAs is usually difficult, an individualized strategy should be considered in patients presenting with BBAs.