Unruptured Cerebral Aneurysms Research Articles

P.123 Is there an association between geographical location of patients in NS and management of unruptured, incidental intracranial aneurysm?

Background: Managing unruptured cerebral aneurysms involves monitoring or repair, with complex factors influencing decision-making. Geographical distance from treatment centers is an understudied factor. This study explores a potential relationship in Nova Scotia between proximity to the sole neurosurgical center in Halifax and aneurysm management. Methods: A prospectively collected neurosurgery database was used to identify all adults seen for unruptured cerebral aneurysm between Jan 1, 2015 - Dec 31, 2020. Demographic data, aneurysm characteristics, follow-up and treatment information were collected. Univariate and multivariate analyses assessed management differences based on geography, controlling for relevant factors including aneurysm size and location. Results: Among 390 patients, 40% were in Halifax, and 60% were outside. No significant difference existed in elective repair (34% vs. 26%, p=0.143) and imaging follow-up frequency (2.26 vs. 2.22, p=0.858). In-person follow-up was higher within Halifax (1.83 vs. 1.43, p=0.008), while virtual follow-up was significant outside Halifax (1.44 vs. 1.01, p=0.003). Overall, in-person and elective repair frequencies declined with the COVID-19 peak, whereas virtual follow-up increased. Conclusions: No significant association was found between patient location and repair decisions. Patients in closer proximity had more in-person follow-ups, while those farther away had more virtual follow-ups. The COVID-19 pandemic affected follow-up frequencies universally.

Intraoperative monitoring of cerebrospinal fluid gas tension and pH before and after surgical revascularization for moyamoya disease

Background: This study aimed to directly measure cerebrospinal fluid (CSF) gas tensions and pH before and after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis for moyamoya disease. Methods: This study included 25 patients with moyamoya disease who underwent STA-MCA anastomosis combined with indirect bypass onto their 34 hemispheres. About 1 mL of CSF was collected before and after bypass procedures to measure CSF partial pressure of oxygen (PCSFO2), CSF partial pressure of carbon dioxide (PCSFCO2), and CSF pH with a blood gas analyzer. As the controls, the CSF was collected from 6 patients during surgery for an unruptured cerebral aneurysm. PCSFO2 and PCSFCO2 were expressed as the ratio to partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide (PaCO2), respectively. Results: PCSFO2/PaO2 was 0.79 ± 0.14 in moyamoya disease, being lower than 1.10 ± 0.09 in the controls (P < 0.0001). PCSFCO2/PaCO2 was 0.90 ± 0.10 in moyamoya disease, being higher than 0.84 ± 0.07 in the controls (P = 0.0261). PCSFO2/PaO2 was significantly lower in pediatric patients than in adult patients and in the hemispheres with reduced cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide than in those with normal CBF but reduced CVR. STA-MCA anastomosis significantly increased PCSFO2/PaO2 from 0.79 ± 0.14 to 0.86 ± 0.14 (P < 0.01) and reduced PCSFCO2/PaCO2 from 0.90 ± 0.10 to 0.69 ± 0.16 (P < 0.0001). There was no difference in CSF pH between moyamoya disease and the controls. Conclusion: PCSFO2/PaO2 was significantly lower in moyamoya disease than in the controls. Its magnitude was more pronounced in pediatric patients than in adult patients and depends on the severity of cerebral ischemia. STA-MCA anastomosis carries dramatic effects on CSF gas tensions in moyamoya patients. CSF may be a valuable biomarker to monitor the pathophysiology of cerebral ischemia/hypoxia in moyamoya disease.

A prospective observational study on hemodynamic risk in cerebral aneurysm growth

Introduction: Hemodynamic factors are thought to play a major role in the development, growth, and rupture of cerebral aneurysms, but the hemodynamics related to enlargement remain unclear. We prospectively enrolled patients with unruptured cerebral aneurysms and performed Computational Fluid Dynamics (CFD) analysis using 3D CT images to investigate differences in hemodynamic environments between aneurysms that grew and those that did not grow over a 3-year period. Methods: This prospective observational study was approved by the National Hospital Organization Central Ethics Review Board. Hemodynamic distributions were examined using ANSYS-CFX software. Patient-specific arterial geometries and inflow velocities were obtained from 3D-CTA and carotid ultrasound Doppler examinations. The distributions of hemodynamic metrics of 17 enlarged and 70 unenlarged aneurysms was compared. In addition, the distributions of hemodynamic metrics of the neck, body, and dome of the aneurysm was also examined in 9 enlarged and 41 non-enlarged cases. A multivariate logistic analysis was performed to investigate the influence of the six hemodynamic metrics, i.e., the time-averaged wall shear stress (TAWSS), time-averaged WSS gradient (TAWSSG), oscillatory shear index (OSI), gradient oscillatory number (GON), transverse WSS (transWSS), and normalized transWSS (NtransWSS) after adjustment forknown risk factors for aneurysm growth, i.e., age, sex, hypertension, smoking history, and aneurysm location, size, and history of subarachnoid hemorrhage. Results: Regarding the distributions of hemodynamic metrics throughout the aneurysm, NtransWSS was significantly higher in the cases with growth than in the cases without growth (odds ratio 2.09, 95% CI 1.02-4.29). the distributions of hemodynamic metrics at each cerebral aneurysm growth site showed that NtransWSS at the dome was significantly higher in the growth cases than in the non-enlargement cases (odds ratio 4.14, 95% CI 1.02-16.80). Conclusion: The data suggest that multidirectional disturbance of wall shear stress is involved in cerebral aneurysm growth, and the disturbance at the dome of the aneurysm may be particularly strongly related. This study was supported by a Grant-in-Aid from the Japanese National Hospital Organization Multi-Center Clinical Research, AMED under grant no. JP15gm0810006h0301 and a JSPS KAKENHI Grant, no. 15K10323. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effects of induced arterial hypertension for vasospasm on unruptured and unsecured cerebral aneurysms (growth and rupture). A retrospective case-control study

ObjectivesUnruptured cerebral aneurysms (UCAs) often coexist with the ruptured one but are typically left unsecured during the weeks following aneurysmal subarachnoid hemorrhage (aSAH). We compared the rate of UCAs rupture or volume growth (≥5 mm3) between patients exposed to induced arterial hypertension (iHTN) for vasospasm and those not exposed (control group). Materials and MethodsFrom 2013 to 2021, we retrospectively included consecutive adult patients with aSAH who had ≥1 UCA. Custom software for digital subtraction angiography (DSA) image analysis characterized UCAs volume, going beyond merely considering UCAs long axis. ResultsWe analyzed 118 patients (180 UCAs): 45 in the iHTN group (64 UCAs) and 73 in the control group (116 UCAs). Systolic blood pressure in the iHTN group was significantly higher than in the control group for several days after aSAH. During the 107 day-monitoring period [interquartile range(IQR):92;128], no UCA rupture occurred in either group. UCA volume analysis was performed in 44 patients (60 UCAs): none of the UCAs in the iHTN group and 3 out of 42 (7%) in the control group had a >5 mm3 volume growth (p=0.55). Other morphologic parameters did not exhibit any variations that might indicate an increased risk of rupture in the iHTN group compared to the control group. ConclusioniHTN did not increase the risk of rupture or volume growth of UCAs within several weeks following aSAH. These reassuring results encourage not to refrain, because of the existence of UCAs, from iHTN as an option to prevent cerebral infarction during cerebral vasospasm.

Exploring the Causal Role of Immune Cells in Cerebral Aneurysm Through Single-Cell Transcriptomics and Mendelian Randomization Analysis.

Cerebral aneurysm (CA) represent a significant clinical challenge, characterized by pathological dilation of cerebral arteries. Recent evidence underscores the crucial involvement of immune cells in CA pathogenesis. This study aims to explore the complex interplay between immune cells and CA formation. We analyzed single-cell RNA sequencing data from the GSE193533 dataset, focusing on unruptured CA and their controls. Comprehensive cell-type identification and pseudotime trajectory analyses were conducted to delineate the dynamic shifts in immune cell populations. Additionally, a two-sample Mendelian Randomization (MR) approach was employed to investigate the causal influence of various immunophenotypes on CA susceptibility and the reciprocal effect of CA formation on immune phenotypes. Single-cell transcriptomic analysis revealed a progressive loss of vascular smooth muscle cells (VSMCs) and an increase in monocytes/macrophages (Mo/MΦ) and other immune cells, signifying a shift from a structural to an inflammatory milieu in CA evolution. MR analysis identified some vital immunophenotypes, such as CD64 on CD14+ CD16+ monocytes (OR: 1.236, 95% CI: 1.064 to 1.435, p=0.006), as potential risk factors for CA development, while others, like CD28- CD8br %CD8br (OR: 0.883, 95% CI: 0.789 to 0.988, p=0.030), appeared protective. Reverse MR analysis demonstrated that CA formation could modulate specific immunophenotypic expressions, highlighting a complex bidirectional interaction between CA pathology and immune response. This study underscores the pivotal role of immune cells in this process through the integration of single-cell transcriptomics with MR analysis, offering a comprehensive perspective on CA pathogenesis, potentially guiding future therapeutic strategies targeting specific immune pathways.

Endovascular treatment of wide-neck bifurcation aneurysms using pCONUS2 HPC bridging device with single antiplatelet: A Case Series.

Wide neck bifurcation aneurysms (WNBA) are technically challenging for both surgical and endovascular treatments. Endovascular treatment for WNBA often requires dual antiplatelet therapy (DAPT) post stent insertion. Novel devices such as the pCONUS2 HPC neck bridging device have an HPC coating which reduces the device thrombogenicity. This theoretically allows for use of single antiplatelet therapy (SAPT), which would be advantageous, particularly in treating ruptured aneurysms. This case series aims to evaluate the safety of SAPT regimen only post stent insertion, by presenting our center early clinical experience in using pCONUS2 HPC neck bridging device in patients that are not suitable for DAPT. We report the cases of 3 patients (2 females, 1 male; range: 64-71 years old) who underwent coil embolization for WNBA using the pCONUS2 HPC device (2 unruptured WNBA, and 1 ruptured WNBA). As all 3 patients were allergic to Aspirin, they could only be started on SAPT post endovascular therapy. All 3 patients were diagnosed with WNBA on angiographic studies. Patient 1 had an unruptured left middle cerebral artery aneurysm; Patient 2 had a ruptured basilar tip aneurysm; Patient 3 had an unruptured anterior communicating artery (ACOM) aneurysm. All 3 WNBA were treated with pCONUS2 HPC neck bridging device. There were no immediate complications. The immediate angiographic result of aneurysm treatment in Patient 1 and Patient 2 demonstrated incomplete occlusions, with delayed complete occlusion of aneurysm in Patient 1 and growth of aneurysmal neck in Patient 2 on follow-up angiograms (range: 6-9 months). No major thrombo-embolic or hemorrhagic complications in the first 2 patients. For Patient 3, the immediate angiographic result of the treated aneurysm demonstrated complete occlusion. However, the patient readmitted 11 days post procedure with cerebral infarction, scoring 5 on the modified Rankin scale on discharge. pCONUS2 HPC as a neck bridging device in treating WNBA has yet to be shown superior to traditional techniques and devices. The theoretical advantage of HPC coating reducing its thrombogenicity requiring only SAPT is yet to be proven safe in clinical practice.

155 Safety and Efficacy of Endovascular Versus Microsurgical Treatment of Unruptured Wide-necked Middle Cerebral Artery Aneurysms: A Propensity-Matched Analysis of the Neurovascular Quality Initiative-Quality Outcomes Database (NVQI-QOD)

INTRODUCTION: There is clinical equipoise regarding the best treatment for unruptured wide-necked middle cerebral artery (WN-MCA) aneurysms. METHODS: The NVQI-QOD registry was queried for patients with unruptured WN-MCA aneurysms. Wide-neck was defined as aneurysm neck = 4 mm or dome:neck ratio = 2. Demographics, aneurysm characteristics, and safety data were queried. Aneurysm occlusion status and modified Rankin score (mRS) at discharge and last follow up were evaluated. Propensity score matching was utilized to match aneurysm size, number of aneurysms treated, patient age and aneurysm status (asymptomatic or symptomatic). RESULTS: Of 670 unruptured MCA aneurysms, 319 were wide-necked. Thirty operations were excluded as the aneurysm was previously treated. 289 operations in 282 patients were assessed (203 EVT, 86 MS). After propensity score matching, there were 86 operations in each group. The median aneurysm size was 5.6 mm (EVT) versus 5.3 mm (MS), p = 0.243. Patients who underwent MS were more likely to have complete occlusion at discharge (90.4% vs. 58.8%, p < 0.001). The median follow up was 404 days in the EVT group versus 157.5 days in the MS group (p = 0.241). Patients who underwent EVT were more likely to have a mRS of zero at discharge (50/59 (84.8%) versus 29/54 (53.7%), p < 0.0003) and last follow up (36/55 (65.5%) versus 13/36 (36.1%), p = 0.006). Safety data showed similar intra-operative (7% EVT vs. 3.5% MS, p = 0.496) and post-operative (4.7% EVT vs. 7% MS, p = 0.750) complication rates. CONCLUSIONS: This report describes the largest-to-date, modern cohort of propensity matched patients undergoing treatment of unruptured WN-MCA aneurysms. Patients undergoing EVT had better functional outcomes at discharge and last follow up though there was significant loss to follow up. Patients undergoing MS were more likely to have complete aneurysm occlusion. Safety data was similar in both groups.

Influence of Perioperative Three-Dimensional Computed Tomography (CT) Angiography and Surgical Clipping for Unruptured Cerebral Aneurysms on Renal Function in Patients with Chronic Kidney Disease

BackgroundSurgical clipping is a valuable treatment option for unruptured intracranial aneurysms in patients with chronic kidney disease (CKD). However, the comprehensive impact of clipping and perioperative three-dimensional computed tomography angiography (3D-CTA) on renal function remains unclear. This study aimed to evaluate the effects of perioperative 3D-CTA and surgical clipping on renal function in patients with CKD. MethodsWe retrospectively analyzed 529 patients who underwent surgical clipping and perioperative 3D-CTA. An estimated glomerular filtration rate (eGFR) < 60 was defined as CKD. Patients were stratified according to their renal function (group 1: eGFR ≥ 60, group 2: 45 ≤ eGFR < 60, group 3: 30 ≤ eGFR < 45, group 4: eGFR < 30 ml/min/1.73 m2), and eGFR was assessed preoperatively and 1 week and several months postoperatively. ResultsOf the 529 patients, 442 did not have CKD and 87 had CKD. Hypertension, hyperlipidemia and hyperuricemia were significantly more common in those with CKD. After the surgery and perioperative series of 3D-CTA, renal function deterioration was not observed in any group, whether in the acute or chronic postoperative period. Notably, eGFR significantly increased in groups 2 (66.7 ± 10.1, p<0.01) and 3 (48.9 ± 9.2, p=0.02) 1 week postoperatively, despite the CKD. ConclusionsSurgical clipping of unruptured intracranial aneurysms and perioperative 3D-CTA with normal-dose contrast media did not impair renal function in patients with CKD. These results could be valuable in determining treatment strategies for those with CKD and intracranial aneurysms.

Prediction of obliteration of unruptured cerebral aneurysm by residual aneurysm volume after flow diverter stent treatment

Introduction There is no methodology to predict aneurysm occlusion using residual volume after flow diverter stent treatment. We retrospectively examined whether residual aneurysm volume at 6 months postoperatively can predict the degree of aneurysm obliteration at 1 year after flow diverter stent treatment. Materials and Methods This single institution study included 101 consecutive patients who underwent flow diverter stent treatment for unruptured cerebral aneurysm. Based on pre-treatment aneurysm volume, the percentage residual volume was calculated 6 months postoperatively. The volume of the aneurysm was determined using the volume calculation function of the cerebral angiography equipment. 1 year postoperatively, patients were classified into two groups: the good obliteration group (GG; O'KellyMarotta [OKM] grading scale: C and D) and the poor obliteration group (PG; OKM: A and B). Statistical analysis was performed to determine if there was a difference in residual aneurysm volume percentage at 6 months postoperatively between the two groups. Results A total of 20 patients were studied: 6 in the GG and 14 in the PG. Mean residual aneurysm volume at 6 months postoperatively in the GG was 33.1% (±34.7), while that in the PG was 80.6% (±24.8) (P=0.018). A residual aneurysm volume of ≥35.2% at 6 months postoperatively was significantly associated with poor aneurysm obliteration at 1 year postoperatively (AUC=0.88, P=0.008). Conclusions Residual aneurysm volume percentage at 6 months after flow diverter stent treatment might be able to predict the likelihood of aneurysm occlusion at 1 year postoperatively

Ultrasonography monitoring with Superb Microvascular Imaging during cerebrovascular surgery

IntroductionUltrasonography (US) is used as a real-time dynamic imaging modality during neurosurgery. A novel Doppler US technique, Superb Microvascular Imaging (SMI), can be used to visualize low-velocity flow of small vessels at high resolution with high frame rates. We visualized vessel flow using this US SMI technique and contrast agent during cerebrovascular surgery. MethodsForty-three patients with an unruptured cerebral aneurysm (control), ischemic and hemorrhagic moyamoya disease, carotid artery stenosis, hemangioblastoma, severe stenosis of the middle cerebral artery, venous angioma, and intracerebral hemorrhage (ICH) underwent neurosurgery with US SMI monitoring using a contrast agent. The diameter, length, and number of penetrating vessels were analyzed in patients with an unruptured cerebral aneurysm (control), moyamoya disease, and ICH. ResultsDiameter and length of cerebral penetrating vessels were significantly increased in patients with moyamoya disease and ICH compared to control patients. The number of penetrating vessels was increased in moyamoya disease patients compared to control and ICH patients. In hemorrhagic moyamoya disease, flow in the penetrating vessels originated from a deep periventricular point and extended to the cerebral surface. Pulsatile cerebral aneurysms during clipping surgery and carotid artery stenosis during carotid endarterectomy were easily identified by SMI. Drastically increased vessel flow in patients with a hemangioblastoma or a venous angioma was observed. ConclusionUsing the US SMI technique and contrast agent, we obtained useful flow information of the vascular disease structure and intracerebral deep small vessels during cerebrovascular surgery. Further quantitative analysis will be informative and helpful for cerebrovascular surgery.

Abstract TMP4: Computational Fluid Dynamics Analysis Offers Novel Preoperative Insights for Unruptured Cerebral Aneurysms - Predicting Aneurysm Wall Thinning and Thickening -

Objective: The preoperative identification of thin-walled regions (TIWRs) and thick-walled regions (TKWRs) in cerebral aneurysms can contribute to enhancing surgical safety. Our recent computational fluid dynamics (CFD) analysis of cerebral aneurysms has demonstrated that the wall shear stress vector cycle variation (WSSVV) and the oscillatory shear index (OSI) can potentially predict TIWRs and TKWRs. This study aims to validate the accuracy of using WSSVV and the OSI to identify these areas and to report on their effectiveness in actual surgeries. Methods: Our cohort comprised 42 patients who underwent cerebral aneurysm clipping surgery at our hospital from January 2019 to September 2022. CFD analysis was performed using Hemoscope. We defined suspected TIWRs as blue regions and suspected TKWRs as red regions on both color maps. We evaluated the positive predictive value (PPV) by comparing these preoperative suspected areas with actual thin and thick areas determined intraoperatively under surgical microscopic observation. Results: Of the 42 patients, 15 were male and 27 were female. The average age was 63 years, and the average aneurysm size was 5.9 mm. The location of the aneurysms was the middle cerebral artery in 18 cases, the internal carotid artery in 15 cases, the anterior communicating artery in 8 cases, and the basilar artery in 1 case. WSSVV yielded a PPV of 83% for TIWRs and a PPV of 78% for TKWRs. In comparison, the OSI demonstrated a PPV of 77% for TIWRs and 76% for TKWRs. Spearman's rank correlation analysis revealed a strong correlation between WSSVV and the OSI; the correlation coefficient was 0.883 (p-value &lt; 0.001). Conclusions: CFD analysis of unruptured cerebral aneurysms could be used to predict TIWRs and TKWRs using both WSSVV and the OSI with an accuracy of approximately 80%. The preoperative evaluation of the wall condition using CFD analysis appears to be highly reliable and is likely to contribute to the safety of cerebral aneurysm surgery.

Discontinuation of antiplatelet therapy after stent-assisted coil embolisation of cerebral aneurysm: a nationwide cohort study

IntroductionStent-assisted coil embolisation (SACE) for the treatment of unruptured cerebral aneurysms has been increasingly used. Long-term advantages of antiplatelet therapy (APT) post-SACE treatment are still not well understood. We investigated...

Intermediate catheter use is associated with complete occlusion and dense packing in coil embolization of unruptured cerebral aneurysms: a propensity score matched study

BackgroundAn intermediate catheter (IMC) can improve the maneuverability and stability of the microcatheter.ObjectiveTo investigate the efficacy and safety of using an IMC in triaxial systems for coil embolization of unruptured...

Isolated ipsilateral abducens nerve palsy and contralateral homonymous hemianopsia associated with unruptured posterior cerebral artery aneurysm: A rare neurological finding.

Cranial nerve palsies can be presenting signs of intracranial aneurysms. There is a classic pairing between an aneurysmal vessel and adjacent nerves leading to cranial neuropathy. Isolated abducens nerve palsy can be a localizing sign of an unruptured vertebrobasilar circulation aneurysm. Aneurysms involving Anterior Inferior Cerebellar Artery (AICA) and Posterior Inferior Cerebellar Artery (PICA) have been reported to be associated with abducens nerve palsy. The symptoms in unruptured aneurysms are due to the mass effect on adjacent neurovascular structures. Most of the abducens nerve palsy resolves following microsurgical clipping. Here, we present a rare case of an unruptured Posterior Cerebral Artery (PCA) aneurysm presenting with abducens nerve palsy and diplopia associated with contralateral hemianopsia which markedly improved following endovascular coil embolization.

Treated unruptured cerebral aneurysm in elderly patients: a single center study

IntroductionThe increase in life expectancy raises the question of the treatment of unruptured intracranial aneurysms in extremely old patients (>80 years). We present results in terms of occlusion and complications in both symptomatic and asymptomatic aneurysm. MethodsAll patients aged >80 years admitted to the Foundation Adolphe de Rothschild between January 1, 2005 and March, 2023 were included. Aneurysms were grouped as compressive and non-compressive. Procedural complications were grouped as symptomatic (i.e., leading to any temporary or permanent neurological deficit) and severe (defined by modified Rankin Scale (mRS) ≥3 at follow-up). ResultsForty-two aneurysms were treated in the study period. Coiling (with or without remodeling) was the treatment of choice in 30 patients. Eighteen patients had compressive aneurysm. Six complications occurred (14.2%), all ischemic. The majority of complications occurred in symptomatic aneurysms, in 4 patients (66.6%). One of the patients treated by flow-diverter had severe complications (mRs ≥3) with hemiplegia. ConclusionIn extremely specific cases, treatment of unruptured aneurysm in people older than 80 years may be considered. Compressive aneurysm is associated with a high risk of complications. Treatments can be endovascular. Further prospective studies are required to confirm this hypothesis.

Rupture Risk Factors and Strategies for Unruptured Distal Anterior Cerebral Artery Aneurysms

Distal anterior cerebral artery (dACA) aneurysms are rare. Ruptured dACA aneurysms typically present with subarachnoid hemorrhage in conjunction with intracerebral hematoma and cause neurological deterioration. This study aimed to determine their risk of rupture and examine associated factors. We retrospectively analyzed patients with dACA aneurysms to compare patient and aneurysm characteristics between ruptured and unruptured aneurysms. Clinical outcome was used the modified Rankin scale. Univariate analyses were performed to identify rupture risk factors. One hundred three patients with dACA aneurysms were examined (51 ruptured and 52 unruptured). The median aspect ratio of ruptured and unruptured aneurysms was 1.69 and 1.22, respectively (P<0.01). The median maximum diameter of ruptured and unruptured aneurysms was 5.2 and 3.1mm, respectively (P<0.01). The median size ratio of ruptured and unruptured aneurysms was 3.32 and 2.17, respectively (P<0.01). Maximum diameter was <5mm in 45.2% of ruptured dACA aneurysms. dACA aneurysm, showing size ratio >2.4 and aspect ratio >1.4, had ruptured in 71.4% and 78.6%, respectively. We suggested that these are the threshold of size ratio and aspect ratio for rupture of dACA aneurysms. A total percentatge of 78.1% of aneurysms with aspect ratio >1.4 and size ratio >2.4 had ruptured. Distal anterior cerebral artery (dACA) aneurysms may rupture, even when small. We found a significant difference between ruptured and unruptured aneurysms with respect to maximum diameter, aspect ratio, and size ratio. Treatment for small aneurysms should be considered based on size ratio and aspect ratio, not just size.

Predicting Morphological Changes to Vessel Walls Adjacent to Unruptured Cerebral Aneurysms Using Computational Fluid Dynamics.

Objective This study compared intraoperative findings with preoperative computed tomography angiography (CTA) and computational fluid dynamics (CFD) analysis of perianeurysmal findings for the indication of possible vessel wall thinning. Materials and Methods Participants comprised 38 patients with unruptured middle cerebral artery aneurysms treated by surgical clipping at our hospital between May 2020 and April 2021. We defined parent artery radiation sign (PARS) as the presence of each of the following three findings in CFD analysis based on preoperative CTA: (1) impingement of the stream line on the outer parent vessel wall of the aneurysm; (2) radiation of wall shear stress vectors outwards from the same site; and (3) increased wall pressure compared with the surrounding area. CFD analysis showing PARS was compared with intraoperative findings. Results In all nine cases with PARS, no morphological abnormalities were found in the same area on CTA. However, intraoperative findings showed thinning of the parent artery wall in one of the nine cases and formation of a very small mass in three cases, differing from CTA findings. All nine patients underwent additional clipping and/or wrapping and coating at the site of PARS. Conclusion Detecting thinning of the vessel wall or the presence of a microaneurysm may be difficult in endovascular therapy, which is based on the visualization of the vessel lumen. CFD analysis suggests the necessity of confirming findings for the vessel wall around an aneurysm by direct manipulation, as the presence of PARS may indicate partial thinning of the vessel wall or formation of a microaneurysm.

Safety and efficacy of endovascular versus microsurgical treatment of unruptured wide-necked middle cerebral artery aneurysms: a propensity score-matched analysis of the NeuroVascular Quality Initiative Quality Outcomes Database Cerebral Aneurysm Registry.

Unruptured, wide-necked middle cerebral artery (WN-MCA) aneurysms have traditionally been considered ideal candidates for microsurgery (MS), although endovascular treatment (EVT) has dramatically increased in popularity with the advent of novel devices such as intrasaccular flow disruptors. The purpose of this study was to evaluate the safety and efficacy of MS versus EVT for unruptured WN-MCA aneurysms. The NeuroVascular Quality Initiative Quality Outcomes Database (NVQI-QOD) Cerebral Aneurysm Registry, a multiinstitutional, prospectively collected procedural database, was queried for cases of unruptured WN-MCA aneurysms treated with MS or EVT between 2015 and 2022. A wide neck was defined as an aneurysm neck ≥ 4 mm or a dome/neck ratio ≤ 2. Demographics and aneurysm characteristics were queried. Propensity score matching (PSM) was utilized to match aneurysm size, number of aneurysms treated, patient age, and aneurysm status. Safety outcomes were evaluated including intraoperative and postoperative complication rates. Aneurysm occlusion status and clinical outcomes using the modified Rankin Scale (mRS) score at discharge and the last follow-up were also assessed. Of 671 unruptured MCA aneurysms, 319 were wide necked. Thirty cases were excluded, as the aneurysm had been previously treated. Two hundred eighty-nine operations (203 EVT, 86 MS) in 282 patients satisfied inclusion criteria. After PSM, there were 86 operations in each group for analysis. The mean aneurysm width was 5.0 (EVT) versus 4.9 mm (MS; p = 0.285). Safety data showed similar intraoperative (7.0% EVT vs 3.5% MS, p = 0.496) and postoperative (4.7% vs 7%, p = 0.746) complication rates. The MS patients were more likely to have complete aneurysm occlusion at discharge (90.4% vs 58.8%, p < 0.001). In a limited subset of patients (52.9%) for whom outcome data were available, the EVT patients were more likely to have an mRS score 0 at discharge (50/59 [84.7%] vs 29/54 [53.7%], p < 0.0003] and at the last follow-up (36/55 [65.5%] vs 13/36 [36.1%], p = 0.006). This study describes a large, modern cohort of propensity score-matched patients who underwent treatment of unruptured WN-MCA aneurysms. Safety data on intraoperative and postoperative complication rates were similar in both treatment groups. MS was more likely to result in complete aneurysm occlusion at discharge. In a subset of patients with available outcome data, EVT was associated with better functional outcomes at discharge and the last follow-up. Given the lack of complete follow-up data and rates of retreatment, these results should be interpreted cautiously.

Prediction of Thrombosis After Coil Embolization of Unruptured Cerebral Aneurysm by Computational Fluid Dynamics Using Porous Media Modeling

Prediction of Thrombosis After Coil Embolization of Unruptured Cerebral Aneurysm by Computational Fluid Dynamics Using Porous Media Modeling

Frailty is a Predictor of Increased Readmissions and Increased Postoperative Complications After Elective Treatment of Unruptured Aneurysms

IntroductionFrailty is a state of decreased physiologic reserve associated with adverse treatment outcomes across surgical specialties. We sought to determine whether frailty affected patient outcomes after elective treatment (open microsurgical clipping or endovascular therapy [EVT]) of unruptured cerebral aneurysms (UCA). MethodsThe National Readmissions Database (NRD) was queried from 2010-2014 to identify patients who had known UCA and underwent elective clipping or EVT. Frailty was assessed using the Johns Hopkins Adjusted Clinical Groups frailty indicator tool. Multivariable exact logistic regression analyses were conducted to assess the associations between frailty and primary outcome variables of 30- and 90-day readmissions, complications, length of stay (LOS) and patient disposition. ResultsOut of 18,483 patients who underwent elective treatment for UCA, 358 (1.9%) met the criteria for frailty. After adjusting for patient and hospital-based factors, frailty (30-day: OR 1.55 95% CI 1.11-2.17, p=0.01; 90-day: OR 1.47 95% CI 1.05-2.06, p=0.02) and clipping (vs. EVT) (30-day: OR 2.12 95% CI 1.85-2.43, p<0.000; 90-day: OR 1.80 95% CI 1.59-2.03, p<0.0001) were associated with increased readmission rates. Furthermore, frailty was associated with increased complications (surgical: OR 2.91 95% Cl 2.27-3.72, p<0.0001; neurological: OR 3.04 95% Cl 2.43-3.81, p<0.0001; major: OR 2.75 95% Cl 1.96-3.84, p<0.0001), increased LOS (IRR 3.08 95% Cl 2.59-3.66, p<0.0001) and nonroutine disposition (OR 3.94 95% Cl 2.91-5.34, p<0.0001). ConclusionsFrailty was associated with increased likelihood of 30- and 90-day readmission after elective treatment for UCA. Frailty was notably associated with several postoperative complications, greater LOS, and non-routine disposition in the treatment of UCA.