Large, giant, and complex anterior communicating artery (ACoA) and A2 anterior cerebral artery (ACA) aneurysms may require a bifrontal interhemispheric approach for better exposure of the aneurysm and bilateral A2-ACA branches and the ability to perform a bypass if needed. The authors sought to investigate the operative techniques and long-term outcomes of ACoA and proximal A2-ACA aneurysms treated with the bifrontal interhemispheric approach. The authors reviewed ACoA and proximal A2-ACA aneurysms treated by microsurgical clipping with or without a bypass via the bifrontal interhemispheric approach from 2005 to 2024 as a subset of all ACoA aneurysms surgically treated at their institution. The indications for this approach were 1) a complex neck requiring exposure of bilateral A1 and A2 vessel segments, and/or 2) need for bypass. Demographic, clinical, and radiographic data were collected and reviewed. Aneurysm occlusion, bypass patency, functional outcomes (modified Rankin Scale [mRS] score), and complications were assessed at the 3-month and long-term (> 12 months) follow-up. Of 383 patients with ACoA or proximal A2-ACA aneurysms treated with microsurgery at the authors' institution, 30 patients met the inclusion criteria. The mean radiographic follow-up was 3.1 years. Sixty percent of patients (18/30) had a subarachnoid hemorrhage. Twenty-five (83.3%) aneurysms were ACoA and 5 (16.7%) were proximal A2-ACA. Bypasses were performed for 16 (53%) aneurysms. Direct side-to-side bypasses were the most common, accounting for 81% (13/16) of all bypasses. Complete aneurysm occlusion was achieved in 90% of aneurysms at the last follow-up. Immediate postoperative patency of the bypass was 100% (16/16). Long-term bypass patency was 87.5% (7/8). Postoperative stroke occurred in 2 patients (6.7%), both of whom recovered with mRS scores < 2 at the 3-month follow-up. The bifrontal interhemispheric approach offers the ability to expose large and giant ACoA aneurysms and bilateral A2 vessel aneurysms, which allows an operative corridor for possible bypass revascularization. The results of this approach were excellent, with a low rate of aneurysm recurrence and complications.

Choosing the side of approach (SoA) in the microsurgical treatment of anterior communicating artery (AComA) aneurysms remains a topic of debate. The aim of this study was to investigate the effectiveness of the open A2 plane as the decisive factor in choosing the SoA. This retrospective cohort study analyzed data from 59 patients who underwent microsurgical treatment for AComA aneurysms from 2017 to 2024 at a single institution. For 19 patients, the SoA was dictated by an accompanying pathology such as another aneurysm or intracerebral hemorrhage. For 40 patients, the open A2 plane was determined due to the location of the ipsilateral A2 by preoperative 3D CTA or DSA. Every patient was evaluated with DSA postoperatively. In superior, anterior, and inferior projecting aneurysms, the posteriorly situated A2 determined the side of the open A2 plane, and in posterior projecting aneurysms, the anteriorly situated A2 directed the approach. Right-sided or left-sided craniotomies were performed for 28 and 12 patients, respectively. The SoA was contralateral to the dominant A1 for 50% of patients, ipsilateral to the dominant A1 for 25%, and there was equal A1 flow for 25% of patients. Two patients, both with inferior orienting aneurysms, experienced early aneurysm rupture. Postoperative DSA showed total neck clipping in 37 of 40 patients. Choosing the SoA based on the open A2 plane facilitated exposure of the aneurysm neck, with high rates of aneurysm closure via a less complicated clip construction.

Background/Objectives: Unruptured aneurysms of the anterior communicating artery (AComA) are associated with a higher risk of rupture and present unique anatomical challenges. Although endovascular techniques have advanced considerably, microsurgical clipping continues to represent an essential treatment option, particularly for complex cases. We conducted a retrospective analysis to evaluate outcomes of microsurgical clipping for unruptured AComA aneurysms over an 18-year period at a high-volume tertiary neurosurgical center. Methods: A retrospective analysis was conducted on 106 patients who underwent microsurgical clipping for unruptured AComA aneurysms between 2002 and 2020. Preoperative, intraoperative, and postoperative parameters were assessed. Excluded were previously ruptured or previously surgically treated aneurysms. Logistic regression models were used to identify predictors of postoperative complications with a focus on aneurysm projection. Results: Complete angiographic occlusion was achieved in 92.2% of cases, with a retreatment rate of 0.9%, which is comparable to the recent literature. Permanent neurological deficits occurred in 5.7% of patients. Posterior aneurysm projection was significantly associated with postoperative infarction and permanent neurological deficits. Intraoperative ICG angiography was associated with a reduced risk of ischemic complications. Conclusions: Microsurgical clipping remains a safe and effective treatment for unruptured AComA aneurysms in selected patients, offering durable occlusion and low complication rates. Aneurysm projection is a key predictor of outcome, and intraoperative ICG angiography significantly enhances surgical safety. These findings support the continued role of microsurgery in the interdisciplinary management of AComA aneurysms.

Endovascular trapping of the internal carotid artery (ICA) remains adefinitive treatment for both aneurysmal and non-aneurysmal conditions when vessel-preserving strategies are not feasible. However, increasing attention has been directed toward the risk of de novo aneurysm formation following ICA sacrifice, presumably due to hemodynamic alterations within the Circle of Willis. This study aimed to evaluate the incidence and potential risk factors for de novo aneurysm development and the growth of pre-existing aneurysms after ICA trapping, particularly focusing on differences based on the underlying pathology, aneurysmal versus non-aneurysmal. Aretrospective, single-center study was conducted on patients who underwent unilateral endovascular ICA trapping between 2003 and 2023, with aminimum of one year of angiographic follow-up. Patients were categorized into the aneurysm-trapping (AT) or non-aneurysm-trapping (NT) group according to the underlying indication for ICA sacrifice. Clinical, angiographic, and procedural data were reviewed to evaluate the development of de novo aneurysms or the progression of pre-existing lesions. Among the 47 included patients (37 and 10 in the AT and NT groups, respectively), de novo aneurysm formation or significant growth of pre-existing aneurysms was observed exclusively in the AT group (10/37, 27.0%), with no such events in the NT group (0/10), showing astatistical trend that did not reach conventional significance (p = 0.064). Most newly developed aneurysms (60%) arose at the anterior communicating artery (ACoA), predominantly in patients with well-developed ACoA collateral flow. Most lesions appeared within two years after ICA trapping. Additional treatment was required in two patients due to progressive enlargement of pre-existing aneurysms. De novo aneurysm formation following ICA trapping appears to occur exclusively in patients with an underlying aneurysmal etiology, particularly at sites of hemodynamic stress such as the ACoA. Close imaging surveillance is recommended during the first two years post-trapping, especially in patients with robust collateral circulation or pre-existing aneurysms.

Background and Objectives: To evaluate factors affecting aneurysm rupture, present our surgical experience with intracranial aneurysms, specifically using the picket-fence clipping technique for giant aneurysms, and highlight the complementary roles of sodium fluorescein (Na-Fl) and indocyanine green (ICG) videoangiography in enhancing surgical precision and patient outcomes. Materials and Methods: We retrospectively analyzed 47 patients who underwent microsurgical clipping of intracranial aneurysms with intraoperative Na-Fl and ICG videoangiography between September 2015 and February 2024. We assessed relationships between patient comorbidities, family history of subarachnoid hemorrhage (SAH), smoking history, aneurysm location and size, and SAH occurrence. Concordance between intraoperative videoangiography and postoperative digital subtraction angiography (DSA) for detecting residual aneurysms was also evaluated. Results: Of the 47 patients (31 female, 16 male; mean age 51.78 ± 11.16 years), 11 (23.4%) presented with SAH. The most common aneurysm location was the middle cerebral artery (MCA) (68.1%). Hypertension and smoking history were significantly higher in the hemorrhage group (p < 0.05). Aneurysm size and anterior communicating artery (AComA) location were also significantly associated with hemorrhage (p < 0.05). Aneurysm size demonstrated significant discriminative power for hemorrhage [AUC: 0.884 (0.827-0.941)], with a cutoff of 7.1 mm yielding 90.9% sensitivity and 94.4% specificity. Five giant MCA aneurysms were treated with the picket-fence technique, with intraoperative ICG and Na-Fl confirming parent artery patency and complete aneurysm occlusion, subsequently confirmed by postoperative DSA. Small remnants were detected in 2 cases (4.26%) on postoperative DSA, both in distal ACA aneurysms, which were also detected by intraoperative videoangiography. Conclusions: Hypertension, smoking history, aneurysm size, and location were important predictors of aneurysm rupture. Intraoperative ICG and Na-Fl videoangiography provide real-time, high-resolution visualization crucial for complex intracranial aneurysm surgery, including the picket-fence technique for giant aneurysms. Their complementary use enhances surgical safety, guides intraoperative decision-making, and contributes to improved outcomes in challenging cases.

Small Ruptured Anterior Communicating Artery Aneurysms in the Endovascular Right-of-First-Refusal Era: Intraprocedural Rupture Risk and Retreatment at Follow-Up.

Introduction Agenesis of the internal carotid artery (ICA) constitutes a rare congenital anomaly, with a reported incidence of less than 0.01% in the general population. The condition was first described during a postmortem examination by Tode in 1787; it is characterized by the complete absence of the ICA, a feature that distinguishes it from aplasia, which involves a lack of development with vestiges of non‐patent vessels, and hypoplasia, defined as incomplete development with a reduced vascular lumen.Individuals with ICA agenesis demonstrate a significantly elevated incidence of cerebral aneurysms, ranging from 25% to 67%, in comparison to the 2%–4% observed in the general population. Subarachnoid hemorrhage (SAH) represents the most common clinical presentation, typically occurring as a consequence of the rupture of an associated intracranial aneurysm. The formation of these aneurysms is postulated to arise from either congenital factors or hemodynamic alterations resulting from abnormal blood flow patterns within collateral pathways. Material and Method A 63‐year‐old male presented to the emergency department with a sudden onset of severe headache and a Glasgow Coma Scale (GCS) score of 14/15. Computed tomography (CT) imaging of the brain revealed subarachnoid hemorrhage (SAH), predominantly within the left sylvian fissure, graded as Fisher grade 3 [Figure 1A] . Subsequent CT angiography (CTA) confirmed agenesis of the left internal carotid artery (ICA) and revealed a triple A2 configuration and a posterior communicating artery (PCA) aneurysm originating from thalamoperforating branches. Of note, imaging revealed a connecting artery between the anterior communicating artery (AComA) complex and the left posterior cerebral artery (PCA), indicative of a left anterior cerebral artery (ACA) to left PCA connection [Figure 1B, 1C] . The absence of the left carotid foramen further differentiated the agenesis from ICA hypoplasia or thrombosis.Given the patient's presentation with a ruptured PCA aneurysm, endovascular coil embolization was performed. The patient's post‐operative hospital course was uneventful, with complete resolution of symptoms. Follow‐up brain CTA at 6 months post‐intervention demonstrated no aneurysm recurrence or residual abnormalities. Result The term agenesis is used when the ICA is absent, complete failure of arterial development without the carotid canal at the skull base, whereas aplasia is a lack of development with presence of vestiges of non‐patent vessels and also of the carotid canal; and hypoplasia is an incomplete development of the ICA artery with a reduced but patent vascular lumen accompanied by a smaller but normally structured carotid canal. Conclusion Unilateral ICA agenesis is a rare condition with a high association with intracranial aneurysms. An understanding of collateral pathways, aneurysm location, and appropriate treatment strategies is essential for managing these complex cases. Figure 1. (A) Computed tomography (CT) imaging of the brain revealed subarachnoid hemorrhage (SAH), predominantly within the left sylvian fissure. (B &amp; C) CT angiography (CTA) with 3D reconstruction confirmed agenesis of the left internal carotid artery (ICA) and revealed a triple A2 configuration a connecting artery between the anterior communicating artery (AComA) complex and the left posterior cerebral artery (PCA).

Introduction/Purpose Anterior communicating artery (ACoA) aneurysms are associated with higher risk of rupture. Flow diverters (FDs) are the first‐line treatment for intracranial aneurysms located on the carotid artery. However, the safety and efficacy of ACoA aneurysms is less established. This systematic review and meta‐analysis aimed to evaluate the safety and effectiveness of FD for ACoA aneurysms. Materials/Methods We conducted a systematic search from inception until June 2025. The primary effectiveness outcome was complete occlusion rate (COR) at last follow‐up defined by Raymond‐Roy and/or O’Kelly‐Marotta scales. Primary safety outcomes were mortality, ischemic and hemorrhagic complications and good functional. Pool estimates were calculated using a random‐effect model. Subgroup analysis was performed based on year of publication. Results Sixteen studies involving 355 patients with 363 ACoA aneurysms met our inclusion criteria. The most common implanted FD was pipeline embolization device, followed by pipeline flex, and silk vista baby. Our pooled overall analysis of COR was 83.9% (95% CI: 78.99‐87.83; P = 0.652; I 2 = 0%). Mortality rate was 0.85% (95% CI: 0.27‐2.59; P = 0.994; I 2 = 0%). Our pooled overall analysis of ischemic and hemorrhagic events were 10.71% (95% CI: 5.31‐20.42; P = 0.008; I 2 = 58%) and 2.02% (95% CI: 0.91‐4.42; P = 0.97; I 2 = 0%), respectively. The overall rate of good functional outcomes was 98.21 % (95% CI: 95.32‐99.33; P = 0.998; I 2 = 0%). Subgroup analysis revealed that newer studies had a COR of 85.35% (95% CI: 79.72‐89.63); P = 0.752; I 2 = 0%) compared to older studies (overall pooled rate was 79.71% [95% CI:68.6‐87.6; P = 0.348; I 2 = 10.1%]). Conclusion Our findings suggests that FDs provide an additional treatment option for ACoA aneurysms, it achieves an adequate complete occlusion at last follow‐up with improvement in complete occlusion rate in latest publications. Additionally, they had a low mortality event, and most patients are functionally independent at follow‐up. However, the used of FDs was associated with higher ischemic complications. Therefore, we still need for larger, prospective trials to draw more definitive conclusion of their used for these aneurysms. image

Introduction Endovascular coil embolization has been effective for cerebral aneurysms since its inception; however, compared with surgical clipping, recanalization remains a concern after coiling. Significant recanalization often necessitates retreatment by re‐coiling or clipping. Established predictors include large/giant size, wide neck, ruptured status, and partial thrombosis. Migration or compaction of coils into intraluminal thrombus can further promote delayed recanalization. Purpose To present a case of recanalization of a partially thrombosed giant ACOM aneurysm after coiling. Methods Patient was encountered during routine clinical practice. Results A 64‐year‐old right‐handed man, heavy smoker and alcohol user with hypertension, presented with new‐onset generalized tonic‐clonic seizure. Brain MRI/MRA demonstrated a giant (3.5 × 2.4 × 3.0 cm) Anterior communicating (ACOM) artery aneurysm with substantial neck filling (17 × 8 × 6 mm) and partial thrombosis. The patient underwent stent‐assisted coil embolization of the aneurysm. At 6‐month follow‐up, diagnostic angiography revealed neck recanalization attributed to flow‐related coil migration into the partially thrombosed sac. He subsequently underwent additional embolization with a Pipeline Flex flow‐diverting stent. Conclusion Patients should be followed by a neurointerventional specialist after coiling to enable early detection of complications. Recanalization should be anticipated in giant, wide‐necked, ruptured, or partially thrombosed aneurysms. Complex intra‐aneurysmal flow and coil migration into mural thrombus can drive recurrence; in such settings, definitive flow diversion may be required at recurrence or considered in initial planning. image

BackgroundIntracranial vessel perforation is a rare but life-threatening complication during endovascular neurointerventions. Despite several described bail-out strategies, there is no consensus on the most effective approach for rapid hemorrhage control. This study aimed to systematically compare common endovascular rescue techniques in a standardized experimental setting.MethodsPatient-specific, 3D-printed vascular models of the anterior circulation were used to simulate standardized vessel perforations at two anatomical sites and three perforation sizes. The impact of the anterior communicating artery (AComA) crossflow was assessed. Proximal balloon guiding catheter inflation, local compliant balloon inflation, temporary coil deployment, and distal intermediate catheter insertion were evaluated against a non-intervention control. The primary outcome was the time it took for 50 ml of fluid extravasation to accumulate.ResultsAs expected, extravasation time inversely correlated with perforation size (ρ = -0.95, p < 0.001). Local balloon inflation at the rupture site most effectively halted leakage. Proximal balloon occlusion was only effective in the absence of an AComA crossflow (p = 0.02). Temporary coil deployment modestly slowed bleeding, especially for small-to-moderate perforations. Distal intermediate catheter placement had no significant effect.ConclusionManaging iatrogenic intracranial vessel perforation is time-critical, as even a brief bleeding time can be fatal. The most effective hemostasis method is compliant balloon inflation at the rupture site. If unavailable, temporary parent artery coiling can reduce bleeding while maintaining perfusion, but it is less effective for larger perforations. Proximal balloon occlusion is only effective in the absence of collateral crossflow.

The anterior communicating artery (AComA) is a common location for intracranial aneurysms and is known for its complex anatomic variability. Understanding its morphology is essential for accurate diagnosis and safe neurosurgical or endovascular procedures. This systematic review aims to compile current research on the surgical anatomy of the AComA and its relationship with pathologic conditions, mainly aneurysms. A total of 20 studies, including anatomic, imaging, surgical, and case reports, were analyzed. Key anatomic variants, such as hypoplasia or aplasia of the A1 segment, fenestration anomalies of the AComA, and the presence of a median artery of the corpus callosum, are often linked to aneurysm formation and rupture risk. Hemodynamic factors, including asymmetry of the A1 segments and a decreased A1-A2 junction angle, significantly increase the odds of aneurysm development. Surgically, features such as the configuration of the A2 segment (eg, closed or open A2 plane) and aneurysm projection direction influence clipping outcomes and complication rates. Preoperative digital subtraction angiography (DSA) has proven superior in identifying complex malformations that may be missed on computed tomography angiography (CTA) or magnetic resonance angiography (MRA). Classification systems provide a structured interpretation of AComA variants with clinical relevance. This review highlights the crucial role of anatomic knowledge in surgical planning and individualized risk assessment for patients with AComA aneurysms.

This study presents the strength parameters of the major intracranial arteries: basilar artery (BA), anterior cerebral arteries (ACA), both left (LACA) and right (RACA), and middle cerebral arteries (MCA), both left (LMCA) and right (RMCA) and the anterior communicating artery (ACoA) obtained by performing single rupture tensile tests on fresh human biological specimens. The measured parameters included maximum Young's modulus, , ultimate strength, , rupture strength, , and rupture strain, , allowing the determination of mean values for each artery type. They were also the basis for a multiple comparison analysis showing that ACA and ACoA significantly differ from BA and MCA. The study also showed that the measured strength parameters are directly dependent on the thickness of the arterial wall, and this effect is about 4-5 times greater for the ACA group and 1.5-3 times greater for ACoA than in the BA + MCA group. Finally, a limit value of maximum relative longitudinal strain of 7% was proposed at low risk of rupture during neurovascular procedures. Obtained parameters and findings have potential applications in optimizing neurointerventional devices, tissue engineering of arterial phantoms or tissue scaffolds, and computational simulations in cerebral hemodynamics.

To describe a case of two arterial rings of the anterior cerebral artery (ACA)-the anterior communicating artery (ACoA) complex diagnosed by magnetic resonance angiography (MRA). A 72-year-old woman with a brain tumor underwent cranial magnetic resonance imaging (MRI) and MRA using a 3-Tesla scanner. MRA was performed using a standard 3-dimensional time-of-flight technique. MRI showed a small convexity meningioma at the right parietal region. MRA showed no pathological lesion. The A1 segment of the left ACA was absent, and bilateral A2 segments were supplied by right ACA. There were two arterial rings at the ACA-ACoA junction, bilaterally. The arterial rings showed triangle configuration, suggesting duplicate origin of the A2 rather than A2 origin fenestration or partial duplication of the ACoA. There was also fetal-type right posterior cerebral artery. ACA-ACoA complex is reported to be the most frequent site of cerebral arterial fenestration. However, duplicated ACoA, partially duplicated ACoA and other arterial rings of the ACA-ACoA complex were confused and reported as a ACoA fenestration. ACoA true fenestration is rarely reported by MRA. The present case had bilateral ACA-ACoA junction triangular rings, suggesting bilateral duplicate origin of the A2 segment of the ACAs. No similar case has been reported previously in relevant English-language literature. Careful observation of MRA is important for the detection of rare arterial variations. Partial volume-rendering images of MRA is useful for identifying complicated small arterial variations.

Abstract There is little information available on clinical presentations, treatment options, and long-term neurovascular consequences of anterior communicating artery (ACoA) aneurysms in children. Although intracranial aneurysms are more common in adults, pediatric cases pose diagnostic and therapeutic challenges due to differences in vascular structure, etiology, and treatment approaches. This study presents a comprehensive review of the literature on ACoA aneurysms in children, highlighting their epidemiology, pathophysiology, clinical manifestations, and treatment modalities, including microsurgical clipping which the patients benefited from. According to our findings, more research is required to contribute to the expanding body of information about pediatric cerebral aneurysms and offering evidence-based management recommendations.

Anatomical variations of the circle of Willis (CoW) are closely associated with the occurrence of intracranial aneurysms (IAs). However, the impact of anatomical variations on the rupture risk of IAs remains unclear. The purpose of this study was to explore the effect of artery absence on the internal flow and rupture risk of IAs. A one-dimensional (1D) solver was combined with a 3-dimensional (3D) fluid-structure interaction (FSI) model to effectively quantify the hemodynamic characteristics inside IA under artery absence. The 1D results showed that the absence of anterior cerebral artery A1 segment (ACA-A1) or posterior cerebral artery P1 segment (PCA-P1) will trigger a compensatory blood flow effect, leading to significant blood flow variations of the anterior communicating artery (ACoA) and internal carotid artery (ICA). By FSI calculation, in the absence of ACA-A1, the maximum wall shear stress (WSS) within the ACoA aneurysm increased by 103% or more compared to the complete CoW due to blood inflow jet. In addition, WSS increased by 45% and 12% in the contralateral ICA and posterior communicating artery (PCoA) aneurysm respectively, whereas it decreased by 33% and 35% in the ipsilateral ICA and PCoA aneurysm, respectively. The absence of PCA-P1 had a less significant impact on the global blood flow of the CoW compared to the absence of ACA-A1, but it still led to an increase in WSS within the ipsilateral ICA and PCoA aneurysms (25% and 22%, respectively). The absence of ACA-A1 or PCA-P1 may serve as an IA rupture risk factor. If ACA-A1 or PCA-P1 absence is identified clinically alongside an aneurysm, proactive treatment strategies are advised.

To describe a case of three rare cerebral arterial variations: (1) accessory posterior cerebral artery (PCA), (2) duplicate origin of the middle cerebral artery (MCA), and (3) accessory anterior cerebral artery (ACA) diagnosed by magnetic resonance angiography (MRA). An 80-year-old man with complete right hemiplegia underwent cranial magnetic resonance imaging (MRI) and MRA using a 3-Tesla scanner. MRA was performed using a standard three-dimensional time-of-flight technique. MRI revealed acute infarction of the left frontal lobe. MRA showed occlusion of the anterior branch of the left MCA. Subsequently, transarterial thrombectomy was performed. Six days later, follow-up MRA was performed, and a well-recanalized left MCA was confirmed. In addition, accessory right PCA supplying the parieto-occipital branch of the PCA, duplicate origin of the right MCA, and accessory ACA arising from X-shaped ACA, which is an absent variation of the anterior communicating artery (ACoA), were confirmed. An accessory PCA, which typically supplies the temporal branch of the PCA, usually arises from the ACoA. We diagnosed the first case of a combination of three rare cerebral arterial variations. Careful observation using MRA is important for the detection of rare arterial variations. Volume-rendering MRA images are useful for identifying superimposed arteries.

Variations of the cerebral arterial circle are frequently observed due to the progressively increasing utilization of diagnostic imaging techniques. Among these variations, the persistence of embryonic vessels, such as the persistent trigeminal artery (PTA), is rare yet holds significant clinical relevance. This presentation details a distinctive case of the PTA coexisting with a partial duplication of the anterior communicating artery (AComA), as identified through magnetic resonance angiography (MRA) in a 41-year-old female patient. The PTA was documented as a vessel linking the basilar artery to the cavernous segment of the left internal carotid artery. The AComA exhibited two branches emanating from the left anterior cerebral artery (LACA), which fused to form a single vessel that anastomosed with the right anterior cerebral artery (RACA). The coexistence of the PTA and AComA variant accentuates the imperative for clinicians to consider such rare anatomical configurations, mainly when performing procedures in proximity to the gasserian ganglion, cavernous sinus, or anterior circulation. The application of three-dimensional imaging remains vital for ensuring precise diagnosis and effective treatment planning.

The anterior communicating artery (AComA) is a key collateral pathway in the Circle of Willis. This study investigated the effects of bilateral inflows and vascular geometry on hemodynamics using computational fluid dynamics (CFD) simulations derived from magnetic resonance angiography (MRA) data in four subjects. Flow rates were measured using phase-contrast MRA (1.5T Siemens) at major anterior circulation segments. CFD models incorporated rigid walls, pulsatile flow, and MRA-derived inlet waveform curves under laminar, incompressible assumptions. Simulated internal carotid artery velocities correlated strongly (>90%) with measurements. While inlet phase lags had limited impact on time-averaged wll shear stress (TAWSS), significant TAWSS differences (>90%) were observed in a subject with marked anterior cerebral artery (ACA) asymmetry (92% diameter ratio). Bilateral ACA inflows are critical for accurate TAWSS estimation, especially in symmetric anatomies. These findings support incorporting patient-specific bilateral inflows in CFD models for improved AComA hemodynamic evaluation and treatment planning.

Comparative Analysis of Morphological and Hemodynamic Parameters in Stable Anterior Communicating and Middle Cerebral Artery Aneurysms.

Patient outcomes in medicine vary significantly when stratified by socioeconomic status (SES). In the cerebrovascular area specifically, rates of treatment of intracranial aneurysms (IAs) and overall outcomes after subarachnoid hemorrhage vary significantly by SES. Less is known about the effect of SES on the selection of seemingly equivocal treatment modalities (microsurgery vs endovascular embolization) for IAs. In this study, the authors examined the impact of SES as measured by the Area Deprivation Index (ADI) on selection of the treatment modality for anterior communicating artery (ACoA) aneurysms, which are readily amenable for either microsurgical or endovascular treatment. A retrospective study was conducted on 136 consecutively treated patients with ACoA aneurysms, unruptured and ruptured, between August 2016 and February 2023 at a large, urban, academic hospital led by dual-trained neurosurgeons. A retrospective review of patient demographics, comorbidities, aneurysm size, morphology, and treatment selection was performed. Univariable and multivariable logistic regression analysis of treatment selection was conducted in the unruptured context, an elective setting, where socioeconomic factors play a strong role in patient-provider shared decision-making, versus the ruptured context, an emergency setting, where the need for expedient intervention diminishes the weight of socioeconomic considerations. Multivariable logistic regression showed that being a patient in the top 50th ADI percentiles was strongly associated with undergoing microsurgical treatment of an ACoA aneurysm in the unruptured context (OR 10.88, 95% CI 1.37-86.59; p = 0.02). Conversely, in the context of ruptured ACoA aneurysms, ADI was not associated with treatment selection (OR 0.16, 95% CI 0.02-1.27; p = 0.08). ADI significantly impacts treatment selection in the management of unruptured ACoA aneurysms. This study highlights that there might be indirect socioeconomic barriers biasing patients from lower SES backgrounds away from endovascular treatment of unruptured ACoA aneurysms compared with their higher SES counterparts.