Neck Remnant Research Articles

Technical Approaches for Coil Embolization of Unruptured Small Anterior Choroidal Artery Aneurysms: A Focus on Anatomical Flow Preservation of the Anterior Choroidal Artery.

The anterior choroidal artery (AChA) supplies the corticospinal tract related to the motor function of the upper and lower limbs. Aneurysms arising at the AChA are not common and exhibit various patterns of involvement of the AChA. Hence, managing an AChA aneurysm poses a high risk of neurological deficits. We report technical issues related to the outcome of coil embolization for unruptured AChA aneurysms. We obtained Institutional Review Board approval for this study. In the past 2 years, 18 consecutive patients (6 males and 12 females, aged 32-68) with unruptured AChA aneurysms were treated using embolization. We present technical details, pre- and post-procedural patient statuses, angiographic outcomes, and recurrence during a mean follow-up period of 12 months (range 3-25). The patients with AChA (n=18) underwent stent-assisted coiling (n=14), coiling (n=2), or stenting only (n=2). The technical strategy for aneurysm embolization included a low-lying approach into the aneurysm, stent-strut abutting (protecting) coil framing to block inflow and avoid compromising AChA flow, and direct intra-aneurysmal angiography via a microcatheter. Angiographic results showed complete occlusion (n=11), neck remnant (n=5), and sac remnant (n=2). During the follow-up, there were 2 recurrences, and 1 of them required a re-procedure. All patients showed no change in clinical status (modified Rankin scale score=0) and did not experience any ischemic or hemorrhagic events during the follow-up period. AChA aneurysms can be managed through embolization using various techniques. Such technical concepts may enhance the safety and improve the outcomes of AChA aneurysm embolization.

8141 A Rare Case of Follicular Adenoma with Osseous Metaplasia and Mature Bone Formation- Is Surveillance Important?

Abstract Disclosure: K. Madani: None. Y. Al-Khazraji: None. D.H. Sacoto: None. G.K. Rai: None. R. Belokovskaya: None. A.A. Franco-Akel, MD: None. Osseous metaplasia and mature bone formation (MBF) are common in malignant thyroid and parathyroid tumors. It is very unusual to have MBF in a benign tumor-like follicular adenoma, as in the case we describe. We found only twelve such cases reported in the literature, and none addressed the cancer risk or need for surveillance for the development of potential malignancy. Thus, further studies are required to investigate the need for surveillance in patients not undergoing excision and in those with remnant thyroid tissue post-removal of the adenoma for recurrence. A 43-year-old female with history of hyperlipidemia and hypothyroidism had an incidental finding of midline neck mass during the evaluation of a left upper extremity lipoma. Ultrasound of the neck showed two nodules in the Left (L) thyroid lobe: a complex nodule measured 2.2 x 1.2 x 2.1 cm and a calcified nodule measuring 1.5 x 0.8 x 0.6 cm. MRI of the neck revealed a 1.9 cm heterogeneously enhancing nodule in the mid to lower pole of the L thyroid lobe. The patient had symptoms suggestive of compression, such as dysphagia, odynophagia, and hoarseness; thus, left hemothyroidectomy was performed. Tissue biopsy was notable for follicular adenoma with osseous metaplasia and mature bone formation. The patient remained clinically and biochemically euthyroid, with only mildly elevated thyrotropin level, and treatment with levothyroxine 25 mcg once daily was initiated. On post-surgical follow-up, there was a lack of data to support close monitoring modality and strategy for the remnant thyroid lobe and neck nodal compartments. We concluded with the patient to follow up in a clinical visit for a physical exam of the neck and to obtain a follow-up sonogram at an interval of six months, in addition to monitoring TSH levels to guide hypothyroidism therapy. Osseous metaplasia has not been established as a premalignant condition, but in certain tissues like the esophagus, metaplasia is a risk factor for malignant conversion, for instance, in Barrett’s esophagus leading to esophageal adenocarcinoma. Moreover, MBF in thyroid tissue has been attributed to the activity of basic fibroblast growth factor (bFGF) and bone morphogenetic protein-2 (BMP-2), which are linked with mitogenesis and tumorigenesis. Thus, the question arises if post-excision surveillance is required in patients with a history of osseous metaplasia in remnant thyroid tissue post-lobectomy or partial thyroidectomy. At this point, more epidemiological data on similar cases may help us understand the true risk of this clinical scenario, in order to develop a reasonable approach for surveillance. Presentation: 6/3/2024

Initial Experience with the New DERIVO® Mini Embolisation Device for the Treatment of Intracranial Aneurysms.

The aim of this study is to present the outcomes of cerebral aneurysm treatment with the DERIVO® mini Embolisation Device (DMD), which is compatible with microcatheters with 0.021-inch inner diameters. Consecutive patients treated with DMD were identified retrospectively. Patient and aneurysm characteristics, procedural findings, clinical outcomes and follow-up imaging results were evaluated. A total of 44 target aneurysms in 30 patients were treated with DMD. The mean age of the patients was 49.9 (range, 4-77 years). Four patients with five aneurysms presented with acute subarachnoid hemorrhage. The mean aneurysm size was 6.8 mm (range, 1.5-22 mm). In 29 (65.9%) aneurysms, adjunctive devices were used for endovascular treatment. The overall mortality rate was 3.3% and procedure-related mortality was 0%. Overall neurologic morbidity was 6.6% and none of the patients had a permanent sequela secondary to the procedure. The mean clinical follow-up period was 20.9 months (range, 3 days-46 months) and the mean DSA follow-up period was 10.9 months. A total of 37 (84.1%) aneurysms demonstrated total occlusion (Raymond-Roy [RR 1]); 3 (6.8%) aneurysms had a neck remnant or infundibular filling at the origin of the jailed side branch (RR 2), 4 (9.1%) aneurysms had residual aneurysm filling (RR 3). For those aneurysms treated with bare DMD, the total occlusion rate was 73.3% at a mean follow-up of 16.1 months. In this initial clinical single-center experience, DMD had a good safety profile and efficacy comparable with the currently used flow diverters.

Endovascular Embolization of Intracranial Aneurysms Using Target Tetra Detachable Coils: Angiographic and Clinical Results from a Single Center.

Background/Objectives: Target tetra detachable coils (TTDCs) aid in achieving effective framing during the coil embolization of small intracranial aneurysms by maintaining a tetrahedral conformation within the aneurysm sac. We aimed to report the initial experience of patients treated for intracranial aneurysms using TTDCs, with a specific focus on efficacy and safety. Methods: We retrospectively reviewed the medical records of 41 patients who underwent the coil embolization of intracranial aneurysms sized ≤10 mm with TTDCs between April and May 2023. Post-procedural angiographic and clinical results were reviewed. Results: Of the 46 aneurysms (45 unruptured and 1 ruptured), 33 (71.7%) were treated with the stent-assisted technique and 13 (28.3%) using the simple coil embolization technique. Post-procedural angiography showed complete occlusion in 41 aneurysms (89.1%), neck remnants in 1 (2.2%), and residual aneurysms in 4 (8.7%). The mean packing density was 34.7% (19.3-46.8%), with TTDC coil length comprising a mean of 88.5% of the total coil length. No major device- or procedure-related complications were observed. During the follow-up, 40 aneurysms (93.0%) demonstrated complete occlusion, while neck remnants were observed in 1 (2.3%), and residual aneurysms in 2 (4.7%). No cases of recanalization were observed. Conclusions: The TTDC is a safe and effective device for the endovascular treatment of intracranial aneurysms. Follow-up studies are required to establish long-term results.

Safety and efficacy of the Contour Neurovascular System for intracranial aneurysm treatment: a retrospective analysis of 76 patients.

The Contour Neurovascular System (CNS) is a novel intrasaccular flow-disrupting device for the treatment of intracranial aneurysms. This study presents the authors' institutional experience and midterm follow-up results with this device. Seventy-six consecutive patients (mean ± SD age 58.9 ± 12.4 years) were treated with the CNS for 76 aneurysms (63 unruptured, 10 recurrent, and 3 ruptured). Aneurysm characteristics, procedural details, and clinical/angiographic outcomes were retrospectively evaluated. The most common aneurysm locations were the basilar tip in 25 (32.9%) cases and the anterior communicating artery in 22 (28.9%). There were 18 (23.7%) sidewall aneurysms. The mean ± SD aneurysm width was 5.6 ± 2.5 mm, and 68 (89.5%) aneurysms were wide-necked. The CNS was successfully implanted in 68 (89.5%) aneurysms, with 11 cases of additional coiling and 1 case each of additional stent and balloon. There were 3 (3.9%) thromboembolic events, of which 1 (1.3%) was symptomatic (a major ischemic stroke) and resulted in morbidity. There were no hemorrhagic events or deaths. At last available follow-up (mean 12 months), 32/56 (57.1%) aneurysms were completely occluded, 16/56 (28.6%) had neck remnants, and 8/56 (14.3%) had an aneurysm remnant. Three (5.4%) aneurysms were retreated. The use of the CNS was safe and feasible but proper aneurysm selection appears to be required, which may be facilitated with increasing operator experience and further study of this device. Similar to other intrasaccular flow disrupters, midterm complete occlusion rates are moderate but may increase with longer follow-up.

Endovascular treatment of aneurysm remnants with the Contour Neurovascular System after previous treatment.

The Contour Neurovascular System (CNS) is a novel intrasaccular flow disrupting device with a semi-3D cup-like shape for the treatment of intracranial aneurysms. This study investigates the potential and limitations of the CNS for embolization of aneurysm remnants after previous treatment. Ten cases of aneurysm recurrence treatment with the CNS were analyzed from a single-center database. Technical success, procedural aspects, complications, and angiographic results were evaluated. The aneurysms (median width: 5.3 mm, median neck width: 3.8 mm) were located in the anterior communicating artery (4), basilar tip (3), internal carotid artery (1), middle cerebral artery (1), and superior cerebellar artery (1). The aneurysms were initially treated endovascularly (9) and by clipping (1). Retreatment failed in one case where the smallest available CNS proved to be too small and had to be removed. Adjunctive coiling was performed in two large remnants of partially thrombosed basilar tip aneurysms. There were no procedural complications or morbidity. At a median follow-up of nine months, 4/8 (50%) aneurysms were completely occluded, 2/8 (25%) had neck remnants, and 2/8 (25%) had aneurysm remnants. The two aneurysm remnants were retreated with coiling and stent-assisted coiling, respectively. CNS treatment of aneurysm remnants may be feasible, especially for shallow, wide-necked aneurysm geometries. Further studies are needed to identify aneurysm subsets that benefit from CNS retreatment and to define mid- and long-term occlusion rates.

Single Neuroform Atlas stent: a reliable approach for treating complex wide-neck bifurcated aneurysms.

Treating wide-neck bifurcated cerebral aneurysms (WNBAs) using various techniques and new devices has shown favorable outcomes. However, endovascular coiling can be technically challenging when the aneurysm neck is incorporated into the parent vessel. Furthermore, although recent research has reported favorable outcomes of Neuroform Atlas stent (NAS)-assisted coiling, broad inclusion criteria have hampered precise evaluations of their effectiveness and safety for treating complex WNBAs. Therefore, this study evaluated whether the use of a single NAS is a safe and effective approach for treating complex WNBAs. We treated 76 complex WNBAs (unruptured, n = 49; ruptured, n = 27) using single NAS-assisted coil embolization and retrospectively analyzed the clinical and angiographic outcomes. In a cohort of 68 patients (mean age, 58.3 ± 11.6 years; males n = 20, 29.4%; females, n = 48, 70.6%), 76 stents were successfully delivered to the target aneurysms, yielding a technical success rate of 98.6%. Complete occlusion was evident in 59 (77.6%) of 76 aneurysms, with neck remnants found in 16 (21.1%) and partial occlusion in 1 (1.3%). Treatment-related morbidities comprised one branch occlusion and one parenchymal hemorrhage. However, no new neurological symptoms of unruptured aneurysms were evident at discharge. The outcomes of 20 of the 27 ruptured aneurysms were favorable (Glasgow Outcome Scale scores of 4 or 5) at the final follow-up assessment (mean 12.2 [6-29] months), except for one initial subarachnoid hemorrhage. Post-treatment angiography revealed complete occlusion in 89.1%, neck remnants in 7.8%, and incomplete occlusion in 3.1% of the aneurysms. Approximately 88.2% of the patients were assessed at least once by follow-up diagnostic or magnetic resonance angiography (mean, 12.5 ± 4.3 [range, 6-29] months), with five (7.8%) minor and two (3.1%) major recurrences. A single NAS is safe and effective for treating WNBAs incorporated into parent vessels.

Lateral Supraorbital Approach for Microsurgical Clipping of Recurrent Ruptured Fetal Posterior Communicating Artery Aneurysm Initially Treated With Woven Endobridge Embolization and Flow Diversion: 2-Dimensional Operative Video

Fetal posterior communicating artery (PComA) is a variant of the cerebral vasculature. 1 Woven endobridge (WEB) embolization carries a good safety profile as treatment for ruptured wide neck PComA aneurysms, without the need for antiplatelet therapy. However, the reported occlusion rates are not optimal. 2 Flow diversion is suboptimal in treating aneurysms originating from fetal PComA. 3 Here we present a case of a 78-year-old female patient with a history of ruptured right fetal PComA aneurysm with wide base. It was initially treated with WEB embolization at an outside hospital. After WEB implantation, the initial follow-up of cerebral angiogram (6 months later) demonstrated a neck recurrence measuring 6 × 3 mm. Approximately 1 year after the initial treatment, pipeline embolization was performed and patient was placed on antiplatelet therapy since. Follow-up images demonstrated a 6 mm × 4 mm persistent neck remnant. Her care was transferred to our institution. Cerebral angiogram obtained 36 months post-WEB implantation showed growth of the neck remnant measuring 9 × 8.5 mm. The WEB device was found to be folded in the aneurysmal fundus. Given this was a growing recurrent previously ruptured fetal PComA aneurysm with a pipeline stent in the internal carotid artery the decision was made to retreat with microsurgical clipping; carotid access at the neck was required for proximal control. We achieved complete aneurysm obliteration through a minimal invasive approach. The patient gave informed consent for surgery and video recording. Institutional Review Board approval was deemed unnecessary.

Evaluation of the shrinkage process of a neck remnant after stent-coil treatment of a cerebral aneurysm using silent magnetic resonance angiography and computational fluid dynamics analysis: illustrative case.

Silent magnetic resonance angiography (MRA) mitigates metal artifacts, facilitating clear visualization of neck remnants after stent and coil embolization of cerebral aneurysms. This study aims to scrutinize hemodynamics at the neck remnant by employing silent MRA and computational fluid dynamics. The authors longitudinally tracked images of a partially thrombosed anterior communicating artery aneurysm's neck remnant, which had been treated with stent-assisted coil embolization, using silent MRA over a decade. Computational fluid dynamics delineated the neck remnant's reduction process, evaluating hemodynamic parameters such as flow rate, wall shear stress magnitude and vector, and streamlines. The neck remnant exhibited diminishing surface area, volume, neck size, dome depth, and aspect ratio. Its reduction correlated with a decline in the flow rate ratio of the remnant dome to the inflow parent artery. Analysis delineated regions within the contracting neck remnant characterized by consistently low average wall shear stress magnitude and variation, accompanied by notable variations in wall shear stress vector directionality. Evaluation of neck remnants after stent-coil embolization is possible through silent MRA and computational fluid dynamics. Predicting the neck remnant reduction may be achievable through hemodynamic parameter analysis.

Woven endo bridge device for recurrent intracranial aneurysms: A systematic review and meta-analysis.

Recurrent intracranial aneurysms present a significant clinical challenge, demanding innovative and effective treatment approaches. The Woven EndoBridge (WEB) device has emerged as a promising endovascular solution for managing these intricate cases. This study aims to assess the safety and efficacy of the WEB device in treating recurrent intracranial aneurysms. We conducted a comprehensive search across multiple databases, including PubMed, Scopus, Embase, and Web of Science, from inception to June 5, 2023. Eligible studies focused on evaluating WEB device performance and included a minimum of five patients with recurrent intracranial aneurysms. The complete and adequate occlusion rates, neck remnant rates, and periprocedural complication rates were pooled using SATA V.17. Our analysis included five studies collectively enrolling 73 participants. Participant ages ranged from 52.9 to 65 years, with 64.4% being female. Aneurysms were wide-necked and predominantly located in the middle cerebral artery, basilar artery, and anterior cerebral artery. Previous treatments encompassed coiling, clipping, and the use of WEB devices. Our study found an overall adequate occlusion rate of 0.80 (95% CI 0.71-0.89), a complete occlusion rate of 0.39 (95% CI 0.28-0.50), and a neck remnant rate of 0.38 (95% CI 0.27-0.48). Periprocedural complications were reported at a rate of 0%, although heterogeneity was observed in this data. Notably, evidence of publication bias was identified in the reporting of periprocedural complication rates. Our findings suggest that the WEB device is associated with favorable outcomes for treating recurrent wide-neck intracranial aneurysms.

Capabilities of Dynamic Magnetic Resonance Angiography in Patients With Cerebral Aneurysms in the Postoperative Period

Introduction: The leading cause of hemorrhagic stroke is a ruptured cerebral aneurysm (CA), accounting for 70%-85% of nontraumatic subarachnoid hemorrhages. The primary goals of CA treatment are to prevent a rupture, thrombosis, or symptoms of mass effect. The main treatment options for intracranial aneurysms are open clipping, flow-diverter device implantation, resection and stenting of aneurysms. Treated aneurysms should be monitored to assess the stability of the occlusion because more than 20% of surgically treated aneurysms are known to recur. Magnetic resonance angiography (MRA) has recently become increasingly attractive for the follow-up of surgically treated CAs because it is noninvasive, does not require hospitalization, and reduces complications associated with the frequent use of cerebral angiography.Objective: To evaluate capabilities of dynamic MRA in postoperative monitoring of patients with CAs.Materials and methods: The study was conducted at the premises of the Scientific Research Institute – Ochapovsky Regional Clinical Hospital No. 1 (Krasnodar, Russian Federation). In a hospital setting, 38 patients with CAs were examined in the late postoperative period. All the patients underwent magnetic resonance imaging, 3-dimensional time-of-flight (3D-TOF) MRA, and dynamic MRA followed by cerebral angiography. Imaging findings (MRA, dynamic MRA, and cerebral angiography) were evaluated by radiologists, x-ray surgeons, and neurosurgeons. They assessed treated aneurysms according to the Raymond-Roy occlusion classification: complete obliteration (class 1), residual neck (class 2), and residual aneurysm (class 3). Untreated aneurysms in patients with multiple CAs and de novo aneurysms were also assessed, and we looked for other vascular malformations.Results: The study was conducted in the late postoperative period from 6 to 18 months. A total of 38 patients participated in the study; of them 27 were women (age, 32-77 years) and 11 were men (age, 32-65 years). Dynamic MRA detected neck remnants of 4 clipped aneurysms and 2 embolized ones, which was confirmed by cerebral angiography. According to the dynamic MRA results, in case of clipped aneurysms neck remnants were found in the anterior communicating artery (n = 2), internal carotid artery (n = 1), and anterior choroidal artery (n = 1). In case of embolized aneurysms, neck remnants were revealed in the internal carotid artery (n = 1) and basilar artery (n = 1). Dynamic MRA also detected 5 additional aneurysms: 2 internal carotid artery aneurysms, 1 basilar artery aneurysm, 1 anterior cerebral artery aneurysm, and 1 anterior communicating artery aneurysm. These findings coincided with those of cerebral angiography. Based on the results of our study, the sensitivity and specificity of dynamic MRA in detecting CA neck remnants and untreated aneurysms were 100%.Discussion: Dynamic MRA findings are fully consistent with those of cerebral angiography in terms of determining an aneurysm occlusion status during postoperative follow-up. As for evaluation of de novo intracranial aneurysms, dynamic MRA is also superior to noncontrast 3D-TOF MRA in assessment of aneurysm shape and neck detection. Therefore, dynamic MRA can clearly visualize the structure of cerebral vessels mainly due to the effect of blood flow and static tissue contrast, and the principle is mainly the effect of multiphase scanning and accumulation of contrast agent.Conclusions: Dynamic MRA has a number of advantages over cerebral angiography, such as noninvasiveness, high-resolution images of the cerebral arteries, absence of radiation exposure, use of iodinated contrast agent, and absence of artifacts from metal clips or embolic material.

Comparison of PED/PED Flex and PED Shield in the treatment of unruptured intracerebral aneurysms.

The object of this study was to compare the efficacy and safety profile of the Pipeline embolization device (PED)/Pipeline Flex embolization device (PED Flex) with that of the Pipeline Flex embolization device with Shield Technology (PED Shield). After introducing the first-generation PED and the second-generation PED Flex with its updated delivery system, the PED Shield was launched with a synthetic layer of phosphorylcholine surface modification to reduce thrombogenicity. This is a retrospective review of unruptured aneurysms treated with PED/PED Flex versus PED Shield between 2017 and 2022 at the authors' institution. Patients with ruptured aneurysms, adjunctive treatment, failed flow diverter deployment, and prior treatment of the target aneurysm were excluded. Baseline characteristics were collected for all patients, including age, sex, past medical history (hypertension, hyperlipidemia, diabetes mellitus), smoking status, aneurysm location, and aneurysm dimensions (neck, width, height) and morphology (saccular, nonsaccular). The primary outcome was procedural and periprocedural complication rates. The study cohort comprised 200 patients with 200 aneurysms, including 150 aneurysms treated with the PED/PED Flex and 50 treated with the PED Shield. With respect to intraprocedural and periprocedural complications, length of stay, length of follow-up, and functional outcome at discharge, there was no significant difference between the two cohorts. At the midterm follow-up, the rate of in-stent stenosis (PED/PED Flex: 14.2% vs PED Shield: 14.6%, p = 0.927), aneurysm occlusion (complete occlusion: 79.5% vs 80.5%, respectively; neck remnant: 4.7% vs 12.2%; dome remnant: 15.7% vs 7.3%; p = 0.119), and the need for retreatment (5.3% vs 0%, p = 0.097) were comparable between the two cohorts. This study suggests that, as compared to first- and second-generation PED and PED Flex, the third-generation PED Shield offers similar rates of complications, aneurysm occlusion, and in-stent stenosis at the midterm follow-up.

Lateral Compression Manipulation: A Simple Approach for Sizing Taller-Than-Wide Intracranial Aneurysms with the Woven EndoBridge Device.

The Woven EndoBridge (WEB) system has established itself as a safe and effective option for managing wide-neck bifurcation aneurysms. Addressing aneurysms with a greater height than width using conventional WEB-sizing methods has proved ineffective due to the inherent configuration of the devices. To overcome this limitation, we propose an intuitive approach that involves swapping the width and height dimensions of the aneurysm to determine the appropriate WEB size. A retrospective analysis was conducted on patients undergoing WEB embolization at a single neuroscience center from March 2013 to February 2023. Twenty-five eligible aneurysms were identified, with the height dimension exceeding the width by an average of 2.33 mm (ranging from 1.4 to 4.5 mm). Of these, 20 cases adhered to the recommended sizing technique, resulting in a 100% success rate of adequate occlusion (14/20 complete occlusion, 6/20 proximal recess filling). In contrast, the outcomes for the remaining 5 cases that did not follow the proposed sizing method were less favorable (P < .05). Among these, 4 cases treated with undersized WEBs showed neck remnants during follow-up, and 1 patient who received an oversized WEB required device replacement during the same procedure. The simple sizing method we proposed for treating taller-than-wide aneurysms has demonstrated promising results, allowing the WEB system to address twice the original size range of treatable aneurysms. Further research with a larger sample size is recommended.

Repeat Flow Diversion for Retreatment of Incompletely Occluded Large Complex Symptomatic Cerebral Aneurysms: A Retrospective Case Series.

Data regarding radiographic occlusion rates after repeat flow diversion after initial placement of a flow diverter (FD) in large intracranial aneurysms are limited. We report clinical and angiographic outcomes on 7 patients who required retreatment with overlapping FDs after initial flow diversion for large intracranial aneurysms. We performed a retrospective review of a prospectively maintained database of cerebrovascular procedures performed at our institution from 2017 to 2021. We identified patients who underwent retreatment with overlapping FDs for large (>10 mm) cerebral aneurysms after initial flow diversion. At last angiographic follow-up, occlusion grade was evaluated using the O'Kelly-Marotta (OKM) grading scale. Seven patients (median age 57 years) with cerebral aneurysms requiring retreatment were identified. The most common aneurysm location was the ophthalmic internal carotid artery (n = 3) and basilar trunk (n = 3). There were 4 fusiform and 3 saccular aneurysms. The median aneurysm width was 18 mm; the median neck size for saccular aneurysms was 7 mm; and the median dome-to-neck ratio was 2.8. The median time to retreatment was 9 months, usually due to symptomatic mass effect. After retreatment, the median clinical follow-up was 36 months, MRI/magnetic resonance angiography follow-up was 15 months, and digital subtraction angiography follow-up was 14 months. Aneurysm occlusion at last angiographic follow-up was graded as OKM A (total filling, n = 1), B (subtotal filling, n = 2), C (early neck remnant, n = 3), and D (no filling, n = 0). All patients with symptomatic improvement were OKM C, whereas patients with worsened symptom burden were OKM A or B. Two patients required further open surgical management for definitive management of the aneurysm remnant. Although most patients demonstrated a decrease in aneurysm remnant size, many had high-grade persistent filling (OKM grades A or B) in this subset of mostly large fusiform aneurysms. Larger studies with longer follow-up are warranted to optimize treatment strategies for atypical aneurysm remnants after repeat flow diversion.

Safety and efficacy of the Woven Endo-Bridge-17 device for intracranial aneurysm treatment: A systematic review and meta-analysis.

The Woven Endo-Bridge (WEB) device revolutionized the treatment of wide-necked bifurcation aneurysms by intrasaccular flow diversion. The latest advancement is the WEB-17 system, offering greater flexibility with fewer wires, enabling treatment of smaller distal aneurysms using smaller microcatheters than the WEB-21 system. We conducted a systematic review following preferred reporting items for systematic reviews and meta-analyses guidelines, analyzing data from seven retrospective cohort studies involving 483 aneurysms treated with the WEB-17 device. Statistical analysis computed pooled prevalence rates and 95% confidence intervals using appropriate models for each outcome and R software version 4.3.1 (R Foundation for Statistical Computing, Vienna, Austria). Technical success was achieved in 475 out of 483 aneurysms treated with the WEB-17 device, with a success rate of 98.34% (95% confidence interval (CI) = 96.72-99.17). Among the successful cases, 4.97% (95% CI = 1.60-14.39) required adjunctive devices. Adequate occlusion, defined as complete occlusion or neck remnants, was observed in 94.41% (95% CI = 88.17-97.46) of cases. Periprocedural complications were infrequent, with thromboembolic complications occurring in 4.93% (95% CI = 3.29-7.30) of cases, hemorrhagic complications in 1.28% (95% CI = 0.58-2.83), and postprocedural neurologic complications in 0.99% (95% CI = 0.31-3.14). Procedure-related morbidity was observed in 1.71% (95% CI = 0.86-3.39) of cases, and there was one procedure-related mortality reported at 0.21% (95% CI = .03-1.50). Mortality unrelated to the procedure occurred in 1% (95% CI = 0.23-4.15). Our findings suggest that the WEB-17 device is associated with a high rate of technical success, favorable angiographic outcomes, and a low rate of periprocedural complications. Further research, including prospective trials, is needed to confirm these findings and establish its safety and efficacy definitively.

Woven EndoBridge Device for Unruptured Wide-Neck Bifurcation Aneurysm: A Multicenter 5-Year Follow-up.

This multicenter study aimed to assess the safety and efficacy of the Woven EndoBridge (WEB) device for treating unruptured wide-neck intracranial bifurcation aneurysms (WIBAs) with short-, mid-, and long-term follow-ups (FUPs). Consecutive patients with unruptured WIBAs treated with WEB between December 2014 and January 2018 were included. Patient, aneurysm, and device characteristics were collected and analyzed retrospectively. Morbidity and mortality rates were determined by collecting intraprocedural, periprocedural, and delayed complications. Aneurysm occlusion was assessed at 1, 3, and 5 years using a 3-grade scale: complete occlusion, neck remnant, and residual aneurysm. Complete occlusion and neck remnant were considered as adequate occlusion. Patients who received re-treatment were also evaluated. The study included 104 consecutive patients (55.8% female, mean age 58.6 ± 11.8 years). Aneurysm maximum size, neck, and dome-to-neck mean were, respectively, 6.9 ± 2.1 mm, 4.5 ± 1.2 mm, and 1.4 ± 0.3 mm. One-year FUP was collected for 95 patients, and 3- and 5-year FUPs were collected for 83 patients. Adequate occlusion was observed at 1-year FUP in 90.5% (86/95), 91.6% (76/83) was observed at 3-year FUP, and 92.8% (77/83) at 5-year FUP. None of the aneurysms bled after treatment. During FUP, 6/83 patients (7.2%) were re-treated for residual aneurysm. Morbidity and mortality rates closely related to aneurysm occlusion were 0% (0/104). The WEB device was safe and effective for treating unruptured WIBAs, both in short-term and long-term FUPs.

Endovascular treatment of multiple intracranial aneurysms.

Multiple intracranial aneurysms are difficult to treat. In order to investigate the effect and safety of endovascular treatment for multiple intracranial aneurysms, 54 consecutive patients with 116 multiple intracranial aneurysms treated with endovascular embolization were retrospectively enrolled. Angiography was performed immediately after embolization and at each follow-up. All clinical data were analyzed. Of the 116 aneurysms, 56 (48.3%) were embolized with coiling alone, 19 (16.4%) with stent-assisted coiling, 31 (26.7%) with stenting alone, and 10 (8.6%) with flow diverters plus coiling. After embolization, 31 (27.6%) aneurysms with stenting alone had no apparent change in size, and in the remaining 84 aneurysms, complete occlusion was achieved in 50 aneurysms (59.5%), near-complete occlusion in 26 (31.0%), and incomplete occlusion in 8 (9.5%). Thrombus formation at the aneurysm neck occurred in 3 patients (5.6%), coil protrusion in 2 (3.7%), and intraprocedural rupture in 1 (1.9%), resulting in a total complication rate of 11.1%. Follow-up angiography was performed in 44 (81.5%) patients 6 to 90 months (mean 49) later. Among 50 completely occluded aneurysms, 38 (76%) aneurysms remained completely occluded, and 4 (8%) aneurysms recurred. Among 26 aneurysms with initial near-complete occlusion, 12 (46.2%) aneurysms with neck remnant had progressive thrombosis to complete occlusion, 2 (7.7%) had no change compared with immediate occlusion, and 5 (19.2%) regrew. In conclusion, endovascular embolization with intracranial stenting and coiling is safe and effective and may play an increasingly important role in the management of multiple intracranial aneurysms.

Abstract 167: Surgical treatment for unruptured Anterior communicating artery aneurysm

Introduction We report the results of endovascular surgery as the first‐line treatment for unruptured anterior communicating artery aneurysms. Methods Fifty‐seven patients (F:M, 30:27; mean age, 65.5 years) underwent surgery for unruptured anterior communicating artery aneurysms in our hospital between January 2018 and January 2023. Results The mean aneurysm dome size was 5.29 mm (2–22 mm), and the mean aneurysm neck size was 3.2 mm (1.5–7 mm). Coil embolization was performed for fifty‐four patients using various adjunctive techniques (simple, 7; double catheter, 15; balloon neck remodeling, 7; stent‐assisted, 26 (LVIS Jr., 12; ATLAS, 14). Neck clipping was performed in 3 cases. The surgical results revealed complete coil embolization in 27, neck remnant in 26, and dome filling in 1 patient(s). The reason for 3 patients treated with neck clipping are patient's preference in one, associated with severe Middle cerebral artery stenosis needed TSA MCA anastomosis on one, and difficulty of embolization in one patient. Postoperative thrombotic complications were observed in 1 patient. The modified Rankin scale scores were 0 in 32 (96.5%) patients, 3 in 1 (1.7%) patients, and 6 in 1 (1.7%) patient. Follow‐up was performed in 55 patients, averaging 29.5 months (3–45 months). However, one patient underwent re‐aneurysm embolization for major recanalization of the aneurysm dome, and none of them suffered from rupture of the treated aneurysm. Conclusion Endovascular surgery may be the first choice of treatment for unruptured anterior communicating artery aneurysms.

Safety and efficacy of the fourth-generation Acandis Acclino flex plus stent for the treatment of complex intracranial aneurysms.

The low-profile Acandis Acclino flex plus (AFP) is a fourth-generation laser-cut microstent with a flexible structure designed for the treatment of a wide variety of aneurysms. We report our single-center experience with this device in the treatment of complex aneurysms. Twenty-eight patients were treated with the Acclino flex plus for 28 aneurysms. Aneurysm characteristics, technical success, complications, clinical outcome, and angiographic results were retrospectively analyzed. The cohort included 8 unruptured untreated aneurysms, 9 unruptured recurrent aneurysms, and 12 ruptured aneurysms with aneurysm diameters ranging from 3 to 23 mm. The anterior communicating artery was the most common location (52%). Stent deployment was successful in 28 cases (97%) with an average of 1.3 stents per aneurysm. The overall procedural complication rate was 17%, including 2 (6.8%) major clinical events (one ischaemic stroke and one aneurysm perforation) and one (3.4%) minor clinical event (one seizure). Angiographic results of 23 aneurysms at a mean of 6 months were complete occlusion in 74%, neck remnants in 13% and aneurysm remnants in 13%. Three patients were retreated. Given the complexity of the aneurysms, the use of the Acclino flex plus was feasible and associated with a favourable safety and efficacy profile. Further studies are needed to evaluate Acclino flex plus in other aneurysm subsets and to define its role in endovascular aneurysm treatment.

Embolization of unruptured wide-necked aneurysms at the MCA bifurcation using the Neuroform atlas stent-assisted coiling: a two-center retrospective study.

The management of middle cerebral artery (MCA) aneurysms remains a controversial topic, and MCA aneurysms have traditionally been treated primarily by surgical clipping. The Neuroform Atlas Stent™ (NAS, available from Stryker Neurovascular, Fremont, California) represents the latest generation of intracranial stents with improved stent delivery system capabilities. This study aims to investigate the safety, feasibility and efficacy exhibited by NAS in treating unruptured aneurysms at the MCA bifurcation. This was a two-center retrospective study involving 42 patients with unruptured wide-necked aneurysms (WNAs) of the MCA treated with the NAS from October 2020 to July 2022. The stent was used to treat 42 cases of unruptured WNA at the MCA bifurcation. Endovascular treatment techniques had a 100% success rate. Immediate postoperative angiography found complete aneurysm occlusion in 34 patients (80.9%) (mRRC 1), neck remnant in 7 patients (16.7%) (mRRC 2), and residual aneurysm in 1 patient (2.4%) (mRRC 3). The thromboembolic complication rate was 2.4% (1/42). The follow-up period was 8.7 months on average (3-16 months). The last angiographic follow-up results revealed complete aneurysm occlusion in 39 patients (92.9%) (mRRC 1), neck remnant in 3 (7.1%) patients (mRRC 2), no aneurysm recanalization or recurrence, and no cases of stent intimal hyperplasia. During the latest clinical follow-up, all patients had an mRS score of 0. Our study demonstrates that the NAS can be applied to treat unruptured WNAs at the MCA bifurcation with favorable safety, feasibility, and efficacy.