Natural course of hemodynamically stable hemispheres contralateral to operated hemispheres in adult patients with ischemic moyamoya diseases.

The necessity of bilateral bypass in adult moyamoya disease (MMD) remains unclear despite its recommendation for pediatric and hemorrhagic cases. We aimed to investigate the natural course of hemodynamically stable unoperated hemispheres after bypass surgery for symptomatic and hemodynamically unstable hemispheres in adult patients with ischemic MMD. Among 288 patients, the mean age at the first operation of the unstable hemispheres was 40.8 ± 12.2 years. The mean follow-up period was 62.9 ± 46.5 months. 45 patients (15.6%) experienced stroke events in the unoperated hemisphere, consisting of hemorrhagic stroke in 8 (2.8%) and ischemic stroke in 37 (12.8%), including progressive transient ischemic attack in 25 (8.7%) and infarction in 12 (4.2%). Among them, 39 patients (13.5%) underwent bypass surgery. The annual risk of total stroke is 3.0%/patient-year, with 2.5% for ischemic stroke and 0.5% for hemorrhagic stroke. The 5- and 10-year cumulative risks of ischemic stroke were 13.4% and 18.3%, respectively, and those of hemorrhagic stroke were each 3.2%. The natural course of hemodynamically stable hemispheres contralateral to the operated ones appeared fairly good. Additional bypass surgery on the unoperated hemispheres should be considered for symptomatic and hemodynamically unstable hemispheres in adult patients with ischemic MMD during the follow-up.

Update on the Vein of Galen Aneurysmal Malformation : Disease Concept and Genetics.

Vein of Galen aneurysmal malformation is one of important pediatric arteriovenous shunt diseases, especially among neonates and infants. Here, early history of the disease identification, basic pathoanatomy with a focus on the embryonic median prosencephalic vein, classification and differential diagnoses, and recent genetic studies are reviewed.

Neovascularization in Outer Membrane of Chronic Subdural Hematoma : A Rationale for Middle Meningeal Artery Embolization.

OBJECTIVE: Chronic subdural hematomas (cSDHs) are generally known to result from traumatic tears of bridging veins. However, the causes of repeat spontaneous cSDHs are still unclear. We investigated the changes in vasculature in the human dura mater and outer membrane (OM) of cSDHs to elucidate the cause of their spontaneous repetition. METHODS: The dura mater was obtained from a normal control participant and a patient with repeat spontaneous cSDHs. The pathological samples from the patient included the dura mater and OM tightly adhered to the inner dura. The samples were analyzed with a particular focus on blood and lymphatic vessels by immunohistochemistry, 3-dimensional imaging using a transparent tissue clearing technique, and electron microscopy. RESULTS: The dural border cell (DBC) layer of the dura mater and OM were histologically indistinguishable. There were 5.9 times more blood vessels per unit volume of tissue in the DBC layer and OM in the patient than in the normal control. The DBC layer and OM contained pathological sinusoidal capillaries not observed in the normal tissue; these capillaries were connected to the middle meningeal arteries via penetrating arteries. In addition, marked lymphangiogenesis in the periosteal and meningeal layers was observed in the patient with cSDHs. CONCLUSION: Neovascularization in the OM seemed to originate from the DBC layer; this is a potential cause of repeat spontaneous cSDHs. Embolization of the meningeal arteries to interrupt the blood supply to pathological capillaries via penetrating arteries may be an effective treatment option.

Extended monitoring of re-coiled cerebral aneurysms after initial postcoiling recanalization: Safety and durability of repeat coil embolization.

PURPOSE: In the endovascular era, postcoiling recanalization of cerebral aneurysms is occurring with greater frequency. Repeat coiling is usually done to prevent rebleeding, although long-term outcomes of re-embolization have yet to be adequately investigated. The present study was undertaken to assess clinical and radiographic outcomes of re-embolization in recanalized aneurysms, focusing on procedural safety, efficacy, and durability. METHOD: In this retrospective review, we examined 308 patients with 310 recurrent aneurysms. All lesions were re-coiled, once major recanalization (after initial coil embolization) was established. Medical records and radiologic data amassed during extended follow-up were then subject to review. Cox proportional hazards regression analysis was undertaken to identify risk factors for subsequent recurrence. RESULT: During a lengthy follow-up (mean, 40.2 ± 33.0 months), major recanalization developed again in 87 aneurysms (28.1%). Multivariable Cox regression analysis linked re-recanalization to initial saccular neck width (p=.003) and autosomal dominant polycystic kidney disease (ADPKD; p<.001). Stent implantation (p=.038) and successful occlusion at second coiling (p=.012) were protective against later recanalization in this setting. The more recent the second embolization was performed, the lower the risk of further recurrence (p=.023). Procedure-related complications included asymptomatic thromboembolism (n = 9), transient ischemic neurologic deficits (n = 2), procedural bleeding (n = 1), and coil migration (n = 1), but there were no residual effects or deaths. CONCLUSION: Repeat coil embolization is a safe therapeutic option for recanalized cerebral aneurysms. Wide-necked status and ADPKD emerged as risks for subsequent recanalization, whereas successful occlusion and stent implantation seemed to reduce the likelihood of recurrence after re-embolization procedures.

Blood-brain barrier disruption imaging in postoperative cerebral hyperperfusion syndrome using DCE-MRI.

Little has been reported about the association between cerebral hyperperfusion syndrome (CHS) and blood-brain barrier (BBB) disruption in human. We aimed to investigate the changes in permeability after bypass surgery in cerebrovascular steno-occlusive diseases using dynamic contrast-enhanced MRI (DCE-MRI) and to demonstrate the association between CHS and BBB disruption. This retrospective study included 36 patients (21 hemispheres in 18 CHS patients and 20 hemispheres in 18 controls) who underwent combined bypass surgery for moyamoya and atherosclerotic steno-occlusive diseases. DCE-MRI and arterial spin labeling perfusion-weighted imaging (ASL-PWI) were obtained at the baseline, postoperative state, and discharge. Perfusion and permeability parameters were calculated at the MCA territory (CBF(territorial), Ktrans(territorial), Vp(territorial)) and focal perianastomotic area (CBF(focal), Ktrans(focal), Vp(focal)) of operated hemispheres. As compared with the baseline, both CBF(territorial) and CBF(focal) increased in the postoperative period and decreased at discharge, corresponding well to symptoms in the CHS group. Vp(focal) was lower in the postoperative period and at discharge, as compared with the baseline. In the control group, no parameters significantly differed among the three points. In conclusion, Vp at the focal perianastomotic area significantly decreased in patients with CHS during the postoperative period. BBB disruption may be implicated in the development of CHS after bypass surgery.

Endovascular Treatment in Precommunicating Segment Aneurysms of Posterior Cerebral Artery.

BACKGROUND: Precommunicating (P1) segment aneurysms of the posterior cerebral artery are rare, with few studies reported to date. Herein, we address the clinical and radiologic outcomes of their endovascular treatment. METHODS: For this study, we retrieved prospectively collected data on 35 consecutive patients with 37 P1 aneurysms, analyzing the clinical ramifications and morphologic outcomes of treatment. All subjects received endovascular interventions between January 2001 and October 2021. RESULTS: There were 16 aneurysms (43.2%) of P1 segment sidewalls and 21 (56.8%) at P1/posterior communicating artery junctions. Five (13.5%) were fusiform, and 14 (37.8%) were ruptured. In 14 patients (40%), 16 aneurysms (43%) were associated with intracranial arterial occlusive disease of the anterior circulation. Selective coiling was undertaken in 34 aneurysms (91.9%), using single (n = 24) or double (n = 4) microcatheters, microcatheter protection (n = 2), or stents (n = 4); and trapping was done in 3 (8.1%). No procedure-related morbidity or mortality resulted. Excluding the trapped lesions, angiographic follow-up of 29 aneurysms obtained >6 months after embolization (mean, 12.4 month) revealed stable occlusion in 21 (72.4%), with some recanalization in the other 8 (minor: 3/29, 10.4%; major: 5/29, 17.2%). CONCLUSIONS: Aneurysms of P1 segment (vs. other locations) are strongly associated with intracranial arterial occlusive disease of the anterior circulation and thus are likely flow related. Endovascular treatment of such lesions seems safe and efficacious, despite the array of technical strategies that their distinctive anatomic configurations impose.

Clinical Outcome of Patients with Poor-Grade Aneurysmal Subarachnoid Hemorrhage with Bundled Treatments: A Propensity Score-Matched Analysis.

BACKGROUND: Poor-grade aneurysmal subarachnoid hemorrhage (aSAH), defined as Hunt and Hess (HH) grades IV and V, is a challenging disease because of its high mortality and poor functional outcomes. The effectiveness of bundled treatments has been demonstrated in critical diseases. Therefore, poor-grade aSAH bundled treatments have been established. This study aims to evaluate whether bundled treatments can improve long-term outcomes and mortality in patients with poor-grade aSAH. METHODS: This is a comparative study using historical control from 2008 to 2022. Bundled treatments were introduced in 2017. We compared the rate of favorable outcomes (modified Rankin Scale score 0-2) at 6 months and mortality before and after the introduction of the bundled treatments. To eliminate confounding bias, the propensity score matching method was used. RESULTS: A total of 90 consecutive patients were evaluated. Forty-three patients received bundled treatments, and 47 patients received conventional care. The proportion of patients with HH grade V was higher in the bundle treatment group (41.9% vs. 27.7%). Conversely, the proportion of patients with fixed pupils on the initial examination was higher in the conventional group (30.2% vs. 38.3%). After 1:1 propensity score matching, 31 pairs were allocated to each group. The proportion of patients with 6-month favorable functional outcomes was significantly higher in the bundled treatments group (46.4% vs. 20.7%, p = 0.04). The 6-month mortality rate was 14.3% in the bundled treatments group and 27.3% in the conventional group (p = 0.01). Bundled treatments (odd ratio 14.6 [95% confidence interval 2.1-100.0], p < 0.01) and the presence of an initial pupil reflex (odd ratio 12.0 [95% confidence interval 1.4-104.6], p = 0.02) were significantly associated with a 6-month favorable functional outcome. CONCLUSIONS: The bundled treatments improve 6-month functional outcome and mortality in patients with poor-grade aSAH.

Delayed ischemic events with low-dose prasugrel medication for stent-assisted coil embolization in intracranial aneurysm patients.

OBJECTIVE: Much emphasis has been put on the use of antiplatelet medication for the prevention of ischemic events in the treatment of cerebral aneurysms with stent assistance. In this regard, the effectiveness and safety of a low-dose prasugrel regimen during the periprocedural period was recently reported. The purpose of this study was to present the outcomes of patients on low-dose prasugrel regimens during the follow-up period after stent-assisted coil embolization (SACE) of cerebral aneurysms. METHODS: For the 396 consecutive patients undergoing SACE procedures, low-dose prasugrel therapy (5 mg of prasugrel and 100 mg of aspirin) was recommended for 3 months after the endovascular treatment. The authors performed a retrospective review of a single-center experience focusing on delayed ischemic events beyond 1 month after treatment. The mean follow-up period was 24.6 ± 11.3 months. RESULTS: In this cohort of patients on a low-dose prasugrel regimen, cerebral infarction occurred in 1 patient (0.3%, 95% CI 0%-1.8%) beyond 1 month after SACE. No intracranial hemorrhage occurred. Overall ischemic events occurred in 14 patients (3.5%, 95% CI 2.1%-5.9%), all within 6 months of the coiling procedure. All patients had transient symptoms. The events occurred within 2 months after cessation of prasugrel in 11 patients (78.6%). Prasugrel maintenance for 6 months was found to result in lower ischemic events compared with maintenance for 3 months. CONCLUSIONS: For patients undergoing SACE, a low-dose prasugrel regimen was a safe and reliable treatment option for the prevention of delayed ischemic events. Transient ischemic events often occurred within 2 months of stopping prasugrel medication.

Is Thyroid Dysfunction Associated with Unruptured Intracranial Aneurysms? A Population-Based, Nested Case-Control Study from Korea.

Background: Few risk factors for the development of intracranial aneurysms (IAs) are known. We investigated the potential role of thyroid diseases in IA development using nationwide real-world data. Methods: A nested case-control study within the National Health Insurance Service-National Sample Cohort data from 2002 to 2019 was performed. A total of 5335 patients with unruptured IA were matched by age and sex with 80,025 controls at a ratio of 1:15. We estimated the odds ratios (ORs) and corresponding confidence intervals [CIs] between thyroid diseases and unruptured IA using a multivariable conditional logistic regression model. Results: Tobacco smoking, use of antihypertensive medication, and hypothyroidism were significantly associated with an elevated risk for unruptured IA in univariate analysis. In multivariable analysis, a history of hypothyroidism was associated with unruptured IA (adjusted OR: 1.46 [CI: 1.26-1.69]). Among patients with hypothyroidism, long-term use of thyroid hormone for >5 years was associated with a reduced risk for unruptured IA (adjusted OR: 0.69 [CI: 0.48-0.99]). A history of hyperthyroidism was associated with a reduced risk for unruptured IAs (adjusted OR: 0.71 [CI: 0.54-0.93]). In secondary analyses of the data according to sex, the respective observed associations between hypothyroidism and hyperthyroidism and the risk of IAs were found to be statistically significant in females but not in males. Conclusions: Hypothyroidism is associated with an increased risk of unruptured IAs, whereas hyperthyroidism is associated with a reduced risk. Overall, the findings suggest that thyroid hormones may play a protective role in the development of unruptured IAs. Further studies are needed to clarify potential direct causality and the biologic mechanisms relating thyroid dysfunction and unruptured IA.

Geometric versus Hemodynamic Indexes for Rupture-Destined Aneurysms: A Retrospective Cohort and a Repeated-Measures Study.

INTRODUCTION: A proper stratification of intracranial aneurysms is critical in identifying rupture-destined aneurysms and unruptured intracranial aneurysms. We aimed to determine the utility of geometric and hemodynamic indexes in differentiating two types of aneurysms and to examine the characteristics of natural evolutionary changes of unruptured aneurysms. METHODS: Rupture-destined aneurysm refers to an aneurysm that undergoes subsequent aneurysmal subarachnoid hemorrhage (SAH). On the other hand, an unruptured intracranial aneurysm is characterized by an aneurysm that does not experience rupture during serial time-of-flight magnetic resonance angiography (TOF-MRA). In addition to geometric indexes, signal intensity gradient (SIG), an in vivo approximated wall shear stress from TOF-MRA, was measured in aneurysms. The difference between the maximum and minimum values of SIG in an aneurysm compared to parent arterial values was designated as the delta-SIG ratio. RESULTS: This study analyzed 20 rupture-destined aneurysms in 20 patients and 45 unruptured intracranial aneurysms in 41 patients with follow-up TOF-MRA. While geometric indexes did not show differences between the two groups, the delta-SIG ratio was higher in the rupture-destined aneurysms (1.5 ± 0.6 vs. 1.1 ± 0.3, p = 0.032). The delta-SIG ratio showed a higher area under the receiver operating characteristic curve for SAH than the size ratio (0.72 [95% CI, 0.58-0.87] vs. 0.56 [95% CI, 0.41-0.72], p = 0.033). The longitudinal re-examination of TOF-MRA in the unruptured intracranial aneurysms revealed evidence of aneurysmal growth, while concurrently exhibiting hemodynamic stability. CONCLUSION: The delta-SIG ratio showed higher discriminatory results between the two groups compared to geometric indexes. Aneurysmal rupture risk should be assessed by considering both geometric and hemodynamic information. This study was registered on ClinicalTrials.gov (NCT05450939).

The Optimal Time between Embolization and Surgery for Hypervascular Spinal Metastatic Tumors : A Systematic Review and Meta-Analysis.

OBJECTIVE: Preoperative transarterial embolization (TAE) of tumor feeders in hypervascular spine metastasis is known to reduce intraoperative estimated blood loss (EBL) during surgery. The effect of TAE varies for several reasons, and one controllable factor is the timing between embolization and surgery. However, the adequate timing remains unclear. This study aimed to evaluate the timing and other factors that reduce EBL in spinal metastasis surgery through a meta-analysis. METHODS: A comprehensive database search was performed to identify direct comparative studies of EBL stratified by the timing of surgery after TAE for spinal metastasis. EBL was analyzed according to the timing of surgery and other factors. Subgroup analyses were also performed. The difference in EBL was calculated as the mean difference (MD) and 95% confidence interval (CI). RESULTS: Among seven studies, 196 and 194 patients underwent early and late surgery after TAE, respectively. The early surgery was defined as within 1-2 days after TAE, while the late surgery group received surgery later. Overall, the MD in EBL was not different according to the timing of surgery (MD, 86.3 mL; 95% CI, -95.5 to 268.1 mL; p=0.35). A subgroup analysis of the complete embolization group demonstrated that patients who underwent early surgery within 24 hours after TAE had significantly less bleeding (MD, 233.3 mL; 95% CI, 76.0 to 390.5 mL; p=0.004). In cases of partial embolization, EBL was not significantly different regardless of the time interval. CONCLUSION: Complete embolization followed by early spinal surgery within 24 hours may reduce intraoperative bleeding for the patients with hypervascular spinal metastasis.

Genome-wide association study identifies novel susceptibilities to adult moyamoya disease.

Genome-wide association study has limited to discover single-nucleotide polymorphisms (SNPs) in several ethnicities. Here, we investigated an initial GWAS to identify genetic modifiers predicting with adult moyamoya disease (MMD) in Koreans. GWAS was performed in 216 patients with MMD and 296 controls using the large-scale Asian-specific Axiom Precision Medicine Research Array. A subsequent fine-mapping analysis was conducted to assess the causal variants associated with adult MMD. A total of 489,966 out of 802,688 SNPs were subjected to quality control analysis. Twenty-one SNPs reached a genome-wide significance threshold (p = 5 × 10-8) after pruning linkage disequilibrium (r2 < 0.8) and mis-clustered SNPs. Among these variants, the 17q25.3 region including TBC1D16, CCDC40, GAA, RNF213, and ENDOV genes was broadly associated with MMD (p = 3.1 × 10-20 to 4.2 × 10-8). Mutations in RNF213 including rs8082521 (Q1133K), rs10782008 (V1195M), rs9913636 (E1272Q), rs8074015 (D1331G), and rs9674961 (S2334N) showed a genome-wide significance (1.9 × 10-8 < p < 4.3 × 10-12) and were also replicated in the East-Asian populations. In subsequent analysis, RNF213 mutations were validated in a fine-mapping outcome (log10BF > 7). Most of the loci associated with MMD including 17q25.3 regions were detected with a statistical power greater than 80%. This study identifies several novel and known variations predicting adult MMD in Koreans. These findings may good biomarkers to evaluate MMD susceptibility and its clinical outcomes.

The ivy sign as a radiological marker for follow-up of postoperative cerebral perfusion status in adult moyamoya disease.

OBJECTIVE: Little is known about the relationship between postoperative changes in cerebral perfusion and the ivy sign representing leptomeningeal collateral burden in moyamoya disease (MMD). This study aimed to investigate the usefulness of the ivy sign in evaluating cerebral perfusion status following bypass surgery in patients with adult MMD. METHODS: Two hundred thirty-three hemispheres in 192 patients with adult MMD undergoing combined bypass between 2010 and 2018 were retrospectively enrolled. The ivy sign was represented as the ivy score on FLAIR MRI in each territory of the anterior, middle, and posterior cerebral arteries. Ivy scores, as well as clinical and hemodynamic states on SPECT, were semiquantitatively compared both preoperatively and at 6 months after surgery. RESULTS: Clinical status improved at 6 months after surgery (p < 0.01). On average, ivy scores in whole and individual territories were decreased at 6 months (all p values < 0.01). Cerebral blood flow (CBF) postoperatively improved in three individual vascular territories (all p values ≤ 0.03) except for the posterior cerebral artery territory (PCAt), and cerebrovascular reserve (CVR) improved in those areas (all p values ≤ 0.04) except for the PCAt. Postoperative changes in ivy scores and CBF were inversely correlated in all territories (p ≤ 0.02), except for the PCAt. Furthermore, changes in ivy scores and CVR were only correlated in the posterior half of the middle cerebral artery territory (p = 0.01). CONCLUSIONS: The ivy sign was significantly decreased after bypass surgery, which was well correlated with postoperative hemodynamic improvement in the anterior circulation territories. The ivy sign is believed to be a useful radiological marker for postoperative follow-up of cerebral perfusion status.

A child who presented with cerebral infarction: Clipping combined with bypass surgery of a thrombosed giant aneurysm.

Background: Cerebral aneurysms are not common among children and most of them are presented with subarachnoid hemorrhage or mass effect. Here, we describe a rare case of a pediatric giant aneurysm presented with cerebral infarction. Case Description: A 38-month-old boy visited the emergency room due to left hemiparesis and left central type facial palsy. Initial magnetic resonance imaging showed acute cerebral infarction on the right basal ganglia and coronal radiata. Furthermore, a thrombosed aneurysm with a diameter of 30.57 mm at the frontal branch of the right middle cerebral artery was observed. A right pterional craniotomy with Sylvian dissection was performed. Superior and inferior divisions of the frontal branch originating from the aneurysm were identified. The superior division was cutoff from an aneurysm and clipping saving the inferior division was done. Subsequently, end-to-end anastomosis was done between a parietal branch of the superficial temporal artery and a superior division from the aneurysm. No acute complication from the operation was observed. Motor power of the left upper extremity recovered after rehabilitation, while fine motor impairment remained 6 months after the surgery. Conclusion: This case illustrates successful treatment of a pediatric giant aneurysm with extremely rare presentation of cerebral infarction, under a meticulous surgical plan and ad hoc modification.

Population-Attributable Risk Fractions for Antiplatelets and Anticoagulants in Spontaneous Intracranial Hemorrhages.

INTRODUCTION: Concerns about spontaneous intracranial hemorrhages (sICHs) have increased over time with the increasing use of antithrombotic agents. Hence, we aimed to analyze the risk and risk fractions for antithrombotics in sICHs in South Korea. METHODS: From the National Health Insurance Service-National Sample Cohort including 1,108,369 citizens, 4,385 cases, aged 20 years or more and newly diagnosed as sICHs between 2003 and 2015, were included in this study. A total of 65,775 sICH-free controls were randomly selected at a ratio of 1:15 from individuals with the same birth year and sex according to a nested case-control study design. RESULTS: Although the incidence rate of sICHs started to decrease from 2007 onward, the use of antiplatelets, anticoagulants, and statins continued to increase. Antiplatelets (adjusted odds ratio [OR] 3.59, 95% confidence interval [CI] 3.18-4.05), anticoagulants (adjusted OR 7.46, 95% CI 4.92-11.32), and statins (adjusted OR 1.98, 95% CI 1.79-2.18) were significant risk factors for sICHs even after adjusting for hypertension, alcohol intake, and cigarette smoking. From 2003-2008 to 2009-2015, the population-attributable fractions changed from 28.0% to 31.3% for hypertension, from 2.0% to 3.2% for antiplatelets, and from 0.5% to 0.9% for anticoagulants. CONCLUSION: Antithrombotic agents are significant risk factors for sICHs, and their contribution is increasing over time in Korea. These findings are expected to draw the attention of clinicians to precautions to be taken when prescribing antithrombotic agents.

Stent-Assisted Coil Embolization Versus Flow-Diverting Stent in Unruptured Vertebral Artery Dissecting Aneurysms: Efficacy and Safety Comparison.

BACKGROUND: Reconstructive strategies for unruptured vertebral artery dissecting aneurysms (VADAs) have increasingly relied on newly developed endovascular devices. However, their clinical performance metrics are seldom reported. OBJECTIVE: To compare stent-assisted coil embolization (SACE) and flow-diverting stent (FDS) deployment as treatments for unruptured VADAs, focusing on efficacy and safety. METHODS: A total of 72 VADAs were submitted to SACE (n = 48) or FDS (n = 24) between April 2009 and September 2021. We reviewed medical records and radiological data to assess efficacy and safety outcomes by method, building an inverse probability of treatment-weighted (IPTW) logistic regression model and conducting survival analyses. RESULTS: Ultimately, 24 aneurysms (33.3%) showed signs of recanalization (major, 14; minor, 10) at 6-month follow-up. Initially determined 6-month rates of overall (SACE, 31.2%; FDS, 41.7%) and major (SACE, 20.8%; FDS, 16.7%) recanalization did not differ significantly by modality; but in the IPTW logistic regression model, adjusted for aneurysm morphology, major recanalization at 6 months was lower for the FDS (vs SACE) subset (odds ratio = 0.196; P = .027). Likewise, the cumulative rate of major recanalization was more favorable for the FDS (vs SACE) subset (hazard ratio = 0.291; P = .048) in IPTW Cox proportional hazards model adjusted for aneurysm morphology. Modality-based assessments of procedural and delayed complications were similar. CONCLUSION: Both reconstructive VADA interventions are safe and effective by adjusting treatment modality depending on the angioanatomic configuration. However, follow-up data after treatment proved more favorable for FDS deployment than for SACE in limiting major recanalization. Case-controlled studies of more sizeable cohorts are needed for corroboration.

Geometric influence of anterior cerebral artery rotation on the formation of anterior communicating artery aneurysm.

OBJECTIVE: Several particular morphological factors that contribute to the hemodynamics of the anterior communicating artery (ACoA) have been documented, but no study has investigated the role of the degree of anterior cerebral artery (ACA) rotation on the presence of ACoA aneurysms (ACoAAs). METHODS: A retrospective study of an institutional aneurysm database was performed; patients with ruptured or nonruptured ACoAAs were selected. Two sex- and age-matched control groups were identified: control Group A (nonaneurysms) and control Group B (middle cerebral artery aneurysms). Measurements of ACA rotation degree were obtained by using a three-dimensional imaging tool. RESULTS: From 2015 to 2020, 315 patients were identified: 105 in the ACoAA group, 105 in control Group A, and 105 in control Group B. The average age at the time of presentation was 64 years, and 52.4% were female. The ACA rotation degree of the ACoAA group was significantly higher than that of control Group A (p <0.01). The A1 ratio and the A1A2 ratio of the ACoAA group were greater than those of control Group A (p <0.01 and p <0.01, respectively). The ACA rotation degree correlated insignificantly with aneurysm size in ACoAA patients (p=0.78). The ACA rotation degree in the ACoAA group was also insignificantly different from that in control B (p=0.11). CONCLUSIONS: The degree of ACA rotation was greater in the ACoAA group than in the nonaneurysm group, and it may serve as an imaging marker for ACoAA.

Endovascular Treatment of Intracranial Aneurysms Using a Microcatheter Protection.

PURPOSE: Stent protective or balloon remodeling techniques have enabled coil embolization of complexly configured aneurysms. Still, the utility of such methods may be limited in some small-caliber and/or inherently tortuous lesions. The present study was conducted to examine the efficacy of microcatheter protection (MCP) when applied in these circumstances. METHODS: This retrospective review included 432 patients with 452 intracranial aneurysms subjected to MCP between April 2001 and January 2021. All available medical records and radiologic data were analyzed, focusing on strategic, safety, and efficacy aspects of the procedures. RESULTS: In a majority (255/452, 56.4%) of cases, MCP was applied throughout entire coiling procedures, as opposed to coil framing (137/452, 30.3%) or filling/finishing (60/452, 13.3%) only. Lesions of the middle cerebral artery (54.9%) predominated, followed by anterior (12.4%) and posterior (11.1%) communicating artery aneurysms. Stent protection was also used occasionally (46/452, 10.2%). Procedural morbidity was low (3/432, 0.7%), limited to symptomatic thromboembolism and procedural leakage, and there were no deaths. Occlusion was successfully achieved by MCP in 424 aneurysms (93.8%). During the follow-up period (mean, 43.4 ± 30.4 months), satisfactory occlusion was documented in 406 of 440 (92.3%) aneurysms. CONCLUSION: MCP is feasible and safe for coil embolization of intracranial aneurysms, in conjunction with multicatheter, balloon, or stenting techniques. MCP may have merit in small-sized or tortuous lesions not amenable to balloon or stent usage, often eliminating the need for stenting altogether.

Role of surgery in management of intracranial dural arteriovenous fistulas.

Intracranial dural arteriovenous fistulas (DAVF) are abnormal connections between intracranial arterial and venous systems within the dural layers. Intracranial DAVFs are rare but can occur wherever dural components exist. The pathogenesis of DAVFs is controversial. Venous hypertension is considered as a main cause of clinical symptoms which are subclassified into asymptomatic, benign and aggressive manifestations. To date, several classification schemes have been proposed to stratify the natural course and risks of DAVFs. Currently, endovascular therapy is the main treatment modality. Moreover, the use of radiosurgery and radiotherapy has been limited. Open surgery is also selectively performed as a main treatment modality for specific types of DAVFs and an adjunctive modality for the endovascular approach. Herein, we present a review of the general perspectives of intracranial DAVFs with an emphasis on the role of surgery.

Trapping and A4-A4 end-to-side anastomosis for the treatment of a ruptured A3 fusiform aneurysm: Potential risk of in-situ bypass.

The treatment of complicated anterior cerebral artery aneurysms remains challenging. Here, the authors describe a case of ruptured complicated A3 aneurysm, which was treated with trapping and in-situ bypass. A 47-year-old man presented to the emergency department with severe headache and vomiting. Computed tomography illustrated acute intracerebral hemorrhage in the right frontal lobe. Digital subtraction angiography (DSA) confirmed a ruptured fusiform A3 aneurysm with lobulation and a daughter sac. Trapping of the ruptured fusiform A3 aneurysm and distal end-toside A4 anastomosis was performed. DSA on postoperative day 7 showed mild vasospasm to the afferent artery. However, 2 months later, DSA demonstrated that the antegrade flow through the anastomosis site had recovered. Thus, surgeons should be aware of the possibility of postsurgical vasospasm of anastomosed arteries, especially in cases of ruptured aneurysms.