Comaneci stent-angioplasty for the optimization of inadequately deployed flow diverter stents.

BACKGROUND AND PURPOSE: In endovascular procedures, inadequate deployment of a flow diverter stent is a highly concerning technical complication that can lead to acute parent vessel occlusion and ischaemic events. This study aimed to assess the off-label use of the Comaneci device in managing technical difficulties associated with flow diversion. MATERIALS AND METHODS: We conducted an analysis of all flow diverter procedures documented in our prospectively collected database. Our objective was to identify patients with inadequately deployed implants who underwent Comaneci stent-angioplasty. Both Comaneci 17 and Comaneci 21 devices were utilized to address and remediate technical complications related to stent deployment. We reviewed anatomical features, technical details, intraprocedural complications, as well as clinical and angiographic outcomes. RESULTS: Thirty-one Comaneci devices were employed to remediate 31 inadequately deployed flow diverter stents. Successful resolution of technical complications associated with flow diverter placement was achieved in all attempted cases. No clinically significant complications were attributed to the technique, and no mortality was observed during the study. CONCLUSION: Technical issues arising from flow diverter stent deployment are formidable complications. Familiarity with appropriate corrective manoeuvres is essential to achieve successful outcomes. The Comaneci device can be safely and effectively incorporated into the range of techniques used to rectify inadequately deployed stents.

Management of Mirror Middle Cerebral Artery Aneurysms: Surgical Results and Morphological Parameters.

AIM: To investigate the safety and applicability of two main methods for treating mirror intracranial aneurysms, based on correlations in their geometric characteristics. MATERIAL AND METHODS: We conducted a retrospective analysis on 125 patients who underwent 138 surgical interventions for MCA aneurysms and were treated with microsurgical clipping and endovascular embolization at the Department of Neurosurgery in the University Hospital "St. Iv. Rilski", Sofia, in 2013-2019. In six of these cases, we observed mirror MCA aneurysms. RESULTS: All six patients with "mirror" aneurysms were female. In one case, a third aneurysm was observed on the anterior communicating artery; hence, a total of 13 aneurysms were treated. The average age of the group was 48.16 years. All patients had known risk factors, such as high blood pressure and tobacco smoking. Four patients presented with aneurysmal subarachnoid hemorrhage (aSAH). All patients underwent surgical treatment in two stages-with obliteration of the intracranial aneurysm leading to subarachnoid bleeding in the first stage and planned surgical intervention within a month in the second stage to exclude unruptured aneurysms. During the one-month interval, there were no SAH incidents. However, we observed one patient with a postoperative neurological deficit and one with recanalization of the aneurysm on follow-up at 3 months, requiring re-embolization. In both cases, endovascular treatment was performed despite the unfavorable anatomical features (aspect ratio ≤1.5 and neck size ≥4 mm). The clinical outcome, in all operated patients, for "mirror" aneurysms of the MCA was reasonable (mRS: 0-2). CONCLUSION: The choice of treatment for "mirror" aneurysms should be determined on an individual basis by the clinical manifestations and morphological characteristics of intracranial aneurysms. In cases of aSAH, where "mirror" aneurysms are present, both can be treated safely via microsurgical clipping or endovascular embolization after thorough investigation and ensuring prioritization of the offending lesion.

Endovascular treatment of wide-necked intracranial aneurysms using the Nautilus Intrasaccular System: initial case series of 41 patients at a single center.

BACKGROUND: Endovascular treatment of intracranial wide-necked and bifurcation aneurysms (WNBA) is technically challenging. The Nautilus Intrasaccular System is designed to provide a mechanical barrier at the aneurysm neck to support coil embolization. We report the results of a single-center series of patients treated for intracranial aneurysms with the Nautilus. METHODS: Clinical and radiological data were retrospectively collected for all patients treated with the Nautilus for an unruptured or ruptured intracranial aneurysm at our center between March 2021 and March 2022. Clinical outcomes (modified Rankin Scale (mRS) scores), Raymond-Roy angiographic occlusion, recanalization, and complications were measured immediately post-procedure and at 3-6-month follow-up. RESULTS: A total of 41 patients of mean age 56.7 years (range 37-83 years) were treated with the Nautilus, with 41 saccular aneurysms (18 (43.9%) unruptured and 23 (56.1%) ruptured). The majority of aneurysms (39/41 (95.1%)) were located in the anterior circulation. We experienced no technical complications. One patient had an asymptomatic post-procedural minor stroke related to the procedure. Immediate Class I occlusion was achieved in 30 (73.1%) patients. The rate of all-cause mortality was 7.3% (3/41). One patient was lost to follow-up. At follow-up, 94.5% (35/37) of patients achieved Class I occlusion and 94.5% (35/37) had an mRS score of 0. There were no procedural-related deaths or permanent morbidities at discharge or follow-up. CONCLUSION: This study demonstrates good safety and effectiveness using the Nautilus Intrasaccular System to treat both ruptured and unruptured intracranial aneurysms. Larger studies are needed to confirm these findings.

Progressive volume reduction and long-term aneurysmal collapse following flow diversion treatment of giant and symptomatic cerebral aneurysms.

Background: The primary goal of conventional endovascular and microvascular approaches is the clinical and radiological resolution of the symptomatic aneurysm-induced mass effect. This study assessed the volume changes and mass effect reduction due to sac shrinkage after treatment with flow diverter stents (FD) for unruptured cerebral aneurysms. Methods: We analyzed retrospectively 36 symptomatic aneurysms that were larger or equal to 25 mm in diameter in patients treated at our center from January 2016 to April 2022. Radiological and clinical outcomes were analyzed, including aneurysmal volume changes and resolution of aneurysm-related symptoms. Results: At 6 months, 25 aneurysms decreased in size, 2 remained unchanged, and 9 aneurysms demonstrated a post-treatment dimensional increase. At 12 months, 30 aneurysms showed a progressive radiological volume reduction. Either no change or negligible shrinkage was observed in the remaining six aneurysms. At 24 months, 32 aneurysms showed aneurysmal shrinkage by a mean 47% volume loss with respect to baseline. At the last follow-up, all 13 patients who had presented with third cranial nerve palsy showed improvements. Complete reversal of the pretreatment edematous changes was confirmed in all cases. The overall post-treatment complication rate was 8.3%, as 3 patients experienced non-fatal delayed rupture of their aneurysm. There was no mortality in this study. Conclusion: Flow diversion could effectively induce progressive aneurysmal shrinkage and resolution of the mass effect associated with giant symptomatic cerebral aneurysms.

Flow Diversion for the Management of Ruptured Intracranial Arterial Infudibular Dilatation: Proof of Principle and Therapeutic Protocol.

Thought to be benign anatomical variants, cerebral infundibular dilatations (ID) are most commonly encountered at the junction of the internal carotid artery (ICA) and the posterior communicating artery (PcomA). The true nature of this entity remains controversial, as some literature reports suggest they should be considered preaneurysmal lesions and a potential source of devastating subarachnoid hemorrhage. This report describes cases of presumably ruptured IDs and their therapeutic endovascular management. We retrospectively reviewed and analyzed patients with isolated subarachnoid hemorrhage (SAH) where the only potential cause was ruptured cerebral IDs, treated or not, between January 2012 and June 2021. Morphological and radiological features, treatment and procedural considerations, clinical and angiographic outcomes were also reviewed. Natural history of the ID is poorly understood, and its relation to SAH remains controversial. Ruptured cerebral IDs can be the suspected cause of bleeding if no other vascular lesion is present during multimodal examinations. Endovascular flow diversion stenting is safe and effective for the proper treatment of ruptured IDs. Pending further validations with longitudinal data are needed to legitimate the natural course of these mysterious lesions.

Comaneci-Assisted Coiling as a Treatment Option for Acutely Ruptured Wide Neck Cerebral Aneurysm: Case Series of 118 Patients.

BACKGROUND: Wide-necked cerebral aneurysms in the setting of acute subarachnoid hemorrhage (SAH) remain difficult to treat with endovascular methods despite recent progress in the neuroendovascular field. OBJECTIVE: To evaluate the effectiveness and safety of the Comaneci device (Rapid Medical, Israel) in endovascular coil embolization of acutely ruptured, wide-necked sidewall, or bifurcation cerebral aneurysms. METHODS: We retrospectively reviewed 45 anterior communicating artery, 24 internal carotid artery, 21 middle cerebral artery bifurcation, 15 anterior cerebral artery, and 13 posterior circulation aneurysms, which were treated using Comaneci-assisted coil embolization from August 2017 to January 2019. We evaluated procedural complications, clinical outcomes, and mid-term angiographic follow-up. Immediate and 90 d-clinical outcome and radiological follow-up were obtained in all patients. RESULTS: Comaneci-assisted coil embolization was performed in 118 acutely ruptured aneurysms. The technique was carried out successfully in all cases. Simultaneous application of 2 separated Comaneci devices was performed in 8/118 cases (6.77%). Periprocedural thromboembolic complications related to the device were seen in 7/118 cases (5.93%) and severe vasospasm of the parent artery after manipulation of the Comaneci device occurred in 5/118 cases (4.2%). The procedural-related morbidity rate was 2.54%, and there was no procedural related mortality. Among the available survivors, angiographic follow-ups were obtained at 3 and 6 mo, and complete aneurysmal obliteration was confirmed in 81/112 (72.3%) and 75/112 (66.9%) cases, respectively. Mid-term follow-up reviewed total recanalization rate of 14.28%. CONCLUSION: Comaneci-assisted embolization of wide-necked intracranial aneurysms in patients presenting with acute SAH is associated with high procedural safety and adequate occlusion rates. Furthermore, dual antiplatelet therapy can be safely avoided in this patient group.

Initial experience with the new ethylene vinyl alcohol copolymer based liquid embolic agent Menox in the endovascular treatment of cerebral arteriovenous malformations.

BACKGROUND AND PURPOSE: Liquid embolic agents (LEAs) are the determinant tool for successful embolization of cranial arteriovenous shunts. There are few currently available LEAs. The aim of the study was to summarize our initial experience with a recently introduced non-adhesive ethylene vinyl alcohol (EVOH) copolymer based LEA (Menox 18) in the endovascular treatment of cerebral arteriovenous malformations. METHODS: From April 2018 to November 2018, 24 patients harboring cerebral arteriovenous malformations underwent endovascular embolization with Menox 18. Clinical features, angiographic results, procedural details, complications, and follow-up details were prospectively collected and retrospectively analyzed. RESULTS: Curative embolization in one endovascular session was achieved in 14/24 (58.3%) of the treated patients. Partial embolization was achieved in 10 patients (42.6%) in whom staged treatment with radiosurgery or microsurgical resection was planned. No mortality was recorded in our series. Clinical complications after embolization occurred in 1/24 (4.66%) patients. No technical complications were noted CONCLUSIONS: Our pilot study suggests that the Menox embolization system offers similar technical and clinical results in comparison with the other currently available LEAs. Further studies with larger cohorts and long term follow-up data are needed to fully evaluate its efficacy.

Initial experience with precipitating hydrophobic injectable liquid in cerebral arteriovenous malformations.

BACKGROUND: Precipitating hydrophobic injectable liquid is a newly introduced liquid embolic agent for endovascular embolization with some technical advantages over other liquid embolic agents. We present our initial experience with precipitating hydrophobic injectable liquid in the endovascular treatment of cerebral arteriovenous malformations. METHODS: From October 2015 to January 2018, 27 patients harboring cerebral arteriovenous malformations underwent endovascular embolization with precipitating hydrophobic injectable liquid 25. Clinical features, angiographic results, procedural details, complications, and follow-up details were retrospectively analyzed. RESULTS: Twenty-seven patients with cerebral arteriovenous malformations were included. Total obliteration in one endovascular session was confirmed for 14/27 (52%) patients. Partial embolization was attained in 13 patients (48%) in whom staged treatment with following radiosurgery or surgery was planned. No mortality was recorded in this series. Complications during or after the embolization occurred in six of 27 (22.2%) patients. CONCLUSION: In our initial experience, precipitating hydrophobic injectable liquid has acceptable clinical outcome comparable to other liquid embolic agents. Although this is the largest reported study in arteriovenous malformation treatment with precipitating hydrophobic injectable liquid, further studies are needed to validate its safety and efficacy.