In-stent restenosis and stented-territory infarction after carotid and vertebrobasilar artery stenting.

BACKGROUND: Prognosis after vertebrobasilar stenting (VBS) may differ from that after carotid artery stenting (CAS). Here, we directly compared the incidence and predictors of in-stent restenosis and stented-territory infarction after VBS and compared them with those of CAS. METHODS: We enrolled patients who underwent VBS or CAS. Clinical variables and procedure-related factors were obtained. During the 3 years of follow-up, in-stent restenosis and infarction were investigated in each group. In-stent restenosis was defined as reduction in the lumen diameter > 50% compared with that after stenting. Factors associated with the occurrence of in-stent restenosis and stented-territory infarction in VBS and CAS were compared. RESULTS: Among 417 stent insertions (93 VBS and 324 CAS), there was no statistical difference in in-stent restenosis between VBS and CAS (12.9% vs. 6.8%, P = 0.092). However, stented-territory infarction was more frequently observed in VBS than in CAS (22.6% vs. 10.8%; P = 0.006), especially a month after stent insertion. HbA1c level, clopidogrel resistance, and multiple stents in VBS and young age in CAS increased the risk of in-stent restenosis. Diabetes (3.82 [1.24-11.7]) and multiple stents (22.4 [2.4-206.4]) were associated with stented-territory infarction in VBS. However, in-stent restenosis (odds ratio: 15.1, 95% confidence interval: 3.17-72.2) was associated with stented-territory infarction in CAS. CONCLUSIONS: Stented-territory infarction occurred more frequently in VBS, especially after the periprocedural period. In-stent restenosis was associated with stented-territory infarction after CAS, but not in VBS. The mechanism of stented-territory infarction after VBS may be different from that after CAS.

Postnatal Imaging for Prediction of Outcome in Patients with Left-sided Congenital Diaphragmatic Hernia.

OBJECTIVE: To evaluate associations between postnatal imaging features and outcome of left-sided congenital diaphragmatic hernia, as defined by overall survival and a requirement for extracorporeal membrane oxygenation (ECMO). STUDY DESIGN: Newborns diagnosed prenatally with left-sided congenital diaphragmatic hernia between January 2013 and September 2021 were studied retrospectively. The esophageal deviation index was newly defined as the largest diameter from the midline to deviated gastric tube divided by the largest transverse diameter of the thoracic cavity on the radiograph. Regression analyses were performed to identify postnatal imaging features associated with overall survival and a requirement for ECMO. The predictive power (ie, area under the curve [AUC] of a time-dependent receiver operating characteristic curve) of prenatal, postnatal, and intraoperative findings for predicting survival were calculated. RESULTS: Ninety-seven patients (54 males; mean gestational age, 38.3 ± 1.9 weeks; mean birth weight, 2956.5 ± 540.0 g) were analyzed. The esophageal deviation index (adjusted hazard ratio [HR], moderate [≥0.19 to <0.24], 6.427 [P = .029]; severe [≥0.24], 33.007 [P < .001]) and right pneumothorax (adjusted HR, 8.763; P = .002) were associated with overall survival and with a requirement for ECMO. Liver herniation on postnatal ultrasound also was associated with overall survival (P < .001) and need for ECMO (P = .001). In addition, the AUC for prediction of 1-year survival from postnatal ultrasound was comparable with that of prenatally or intraoperatively detected liver herniation (0.93; 95% CI, 0.88-0.97). CONCLUSIONS: The esophageal deviation index, right pneumothorax, and liver herniation observed by postnatal imaging have prognostic value in patients with left-sided congenital diaphragmatic hernia.

High serum total cholesterol associated with good outcome in endovascular thrombectomy for acute large artery occlusion.

BACKGROUND: The effect of cholesterol on the functional outcome after endovascular thrombectomy (EVT) is still controversial. This study aimed to investigate whether the lipid profile is associated with the EVT prognosis. METHODS: We retrospectively analyzed patients with emergent large vessel occlusion who underwent EVT. The blood lipid levels were measured in the fasting state, 1 day after admission. We divided patients into terciles of serum total cholesterol (TC) levels and compared the clinical characteristics among the groups. The factors associated with a good outcome at 3 months (modified Rankin scale 0-2) were investigated, considering the stroke mechanism and recanalization status. RESULTS: Among 274 patients, good outcomes were observed in 108 (39.4%) patients. Low initial severity (odds ratio (OR), 0.91, 95% confidence interval (CI), 0.858-0.954; p < 0.001) and high TC level (1.35, 1.034-1.758; p = 0.041) were associated with good outcomes. In patients with cardioembolism, young age (0.95, 0.915-0.991; p = 0.021), low initial severity (0.92, 0.857-0.988; p = 0.024), and high TC level (1.60, 1.019-2.499; p = 0.036) were associated with good outcomes. The lipid profile was not associated with a functional outcome in those with large artery atherosclerosis. In patients with complete recanalization, young age (0.97, 0.941-0.994; p = 0.016), low initial severity (0.91, 0.864-0.961; p = 0.001), absence of diabetes (0.45, 0.218-0.947; p = 0.035) or any hemorrhage (0.33, 0.142-0.760; p = 0.009), and high TC level (1.40, 1.031-1.879; p = 0.031) were associated with good outcomes. CONCLUSIONS: A high TC level was associated with favorable outcomes after EVT, especially in patients with cardioembolism and complete recanalization.

Feasibility of low-dose digital subtraction angiography protocols for the endovascular treatment of intracranial dural arteriovenous fistulas.

BACKGROUND: Among neurointerventional procedures, the embolization of complex shunt lesions usually requires more radiation dose. We aimed to evaluate the procedural outcome and safety in using low-dose DSA protocols for intracranial dural arteriovenous fistula (AVF) embolization treatment. METHODS: Between January 2014 and July 2018, 55 patients with dural AVFs who underwent endovascular treatment were included in the study. The low-dose group (n = 27) included from January 2016 used various low-dose DSA protocols made by modifying the thickness of the copper filter or the detector entrance dose. We compared radiation dose metrics, such as air-kerma, kerma-air product (KAP), and fluoroscopy time, as well as clinical and imaging outcomes with the conventional-dose group (n = 28) included before January 2016. RESULTS: The total KAP was 40.1% lower in the low-dose group (87.9 vs. 146.7 Gy cm2, p = 0.002). The average number of DSA runs (25.1 vs. 25.5, p = 0.86) and fluoroscopy times (77.4 vs. 69.7 min, p = 0.48) were similar between the groups. An immediate favorable occlusion rate (total or near total occlusion) was achieved in 41 (74.5%) patients. Ten patients (18.2%) underwent additional procedures due to residual (n = 6) and/or recurrent (n = 5) lesions. At a median of 10 months follow-up, 45 patients (86.5%) had achieved favorable occlusion. Treatment outcomes showed no significant between-group differences. There was one case (1.8%) of procedure-related complications in the low-dose group. All but one patient showed favorable clinical outcomes (modified Rankin score ≤ 2). CONCLUSION: The low-dose protocols were feasible by showing significant radiation dose reduction and acceptable procedural outcome.

Tailored antiplatelet agent medication in clopidogrel hyporesponsive patients before stent-assisted coiling: single-center experience.

PURPOSE: In patients requiring stent procedures, resistance or hyperresponsiveness to antiplatelet medications is often observed. This study aims to evaluate the efficacy and safety of tailoring medications in these patients. METHODS: This retrospective study included 223 patients who underwent endovascular treatment for intracranial aneurysm between October 2018 and October 2019. Patients were categorized as hyporesponsive, hyperresponsive, and normoresponsive groups according to the initial PRU response. For the hypo- or hyperresponders, we tailored medication by modifying the dose or changing the drug. PRUs before and after tailoring were compared in each group. PRU reponses in patients who underwent Cytochrome P450 2C19 (CYP2C19) genotyping were also determined. RESULTS: Of the 73 clopidogrel-resistant patients, the mean PRU values after tailoring showed a greater decrease in the group that switched to prasugrel (n = 56), from 223 to 131, than in the clopidogrel reloading group (n = 17), from 238 to 209. In 31 hyperresponders, PRU increased from 49 to 94 after the dose adjustment. CYP2C19 genotyping showed that PRU tended to increase as the number of mutated alleles increased. There were five (2.3%) ischemic events (three transient ischemic attacks and two minor strokes) in a mean follow-up of 8 months, but no hemorrhage. CONCLUSIONS: The stent-assisted coiling was successfully performed with acceptable range of ischemic events and without hemorrhage in all patients, including those who applied tailored medication. Low-dose prasugrel was effective for obtaining appropriate PRU values for initial medication as well as for clopidogrel-resistant patients. The genetic test did not provide reliable results in determining clopidogrel resistance.

Estimated radiation dose according to the craniocaudal angle in cerebral digital subtraction angiography: Patient and phantom study.

BACKGROUND AND PURPOSE: Routine use of cranial angulation with 15-20 degrees, craniocaudal angled (CC) view, for cerebral digital subtraction angiography (DSA) helps minimize bone subtraction artifacts with less overlapping of the vessels, however, it may increase the radiation dose. We designed the phantom and patient studies to determine the effect of the angulation to the radiation dose and the feasibility of true posteroanterior angled (PA) view, in cerebral DSA. MATERIALS AND METHODS: In the phantom study, frontal DSA was simulated with variable angulations. In the patient study with thirty-one subjects, one internal carotid arteriogram was obtained with the CC view and the other, PA view in every patient. The dose-area product (DAP) and reference air-kerma (AK) were measured and compared between the angles. A qualitative analysis was performed to assess the diagnostic performance of the DSA over the angles. RESULTS: The phantom study confirmed that the greater craniocaudal angles caused higher radiation exposure. Especially, the radiation dose (AK) of the CC view was 5.4% higher than that of the PA view. In the patient study, the radiation dose of the PA view was significantly lower compared to the CC view (1.44 vs. 1.63 mGy, AK). In 4 patients, the dose particularly jumped when applying the CC view as the copper filter was automatically removed. The diagnostic ability of the DSA with the PA view tended to be higher without significance. CONCLUSIONS: In a daily routine cerebral angiography, a simple modification of the angle may help to minimize the radiation dose.

New grading system for the clinical evaluation of patients with spinal vascular lesions.

PURPOSE: Neurointerventional approaches have improved myelopathy in patients with spinal vascular lesions by providing effective management, particularly when surgical approaches are difficult. However, there have been challenges in describing and comparing recovery status during the post-treatment period. METHODS: We evaluated 43 patients with venous congestive myelopathy (VCM) using Aminoff-Logue Disability Scale for gait (AL-G) and micturition (AL-M) scores. These results were compared with our new PSMS grading system that evaluates four categories (grades 0-3): pain, sensory symptoms, motor deficit, and sphincter change. Simple linear regression was used to identify the association or trend among the scales. We also calculated an overall area under the receiver operating characteristic curve to compare the predictive ability of the PSMS system with that of the previous grading system (AL-G and AL-M). RESULTS: Compared with other grading system, the PSMS system was more sensitively correlated with patient status and the results were easy to compare with previous clinical statuses during follow-up. The PSMS system also measured pain, which is commonly associated with spinal dural arteriovenous fistula and not precisely evaluated by other grading system. CONCLUSIONS: The new PSMS grading system for patients with VCM correlated well with the previously used systems and included pain evaluation. This new grading system is an easy tool for the evaluation and comparison of outcomes before and after endovascular treatment.

Virtual stenting of intracranial aneurysms: application of hemodynamic modification analysis.

BACKGROUND: Practical application of hemodynamic modification analysis based on computational fluid dynamics (CFD) in intracranial aneurysms is still under study. PURPOSE: To determine the clinical applicability of virtual stenting of aneurysms by comparing the simulated results with clinical outcome of real stenting. MATERIAL AND METHODS: Three-dimensional (3D) digital subtraction angiography (DSA) images were imported to a dedicated integrated prototypic CFD platform (Siemens Healthcare GmbH) which allows all necessary steps of 3D models for CFD analysis. The results of CFD simulation with virtual implantation of a stent can be visualized in the same platform for qualitative comparisons on a color-coded volume visualization window. Five small intracranial aneurysms with and without virtual stenting were analyzed and assessed on a qualitative level. Expert rating were performed for evaluating the simulated results, and comparing those to the long-term follow-up outcomes of real stenting. RESULTS: CFD simulation after virtual stenting was feasible in five differently located aneurysms and corresponded to the long-term changes of stented aneurysms by showing alteration in flow pattern. There was no significant difference (P = 0.5) between the simulated hemodynamic changes after virtual stenting and the angiographic changes after stenting in four aneurysms except one. There was good agreement regarding the assessment of the changes by two raters (kappa = 0.657). CONCLUSION: CFD analysis using patient-specific virtual stenting of the CFD platform may be used as a simple and less time-consuming test tool predicting the involution of aneurysms after stent placement by analyzing the vector visualization of the flow changes.

Facilitated Retrograde Access via the Facial Vein for Transvenous Embolization of the Cavernous Sinus Dural Arteriovenous Fistula with Isolated Ophthalmic Venous Drainage.

Management of cavernous sinus dural arteriovenous fistula (CSDAVF) continues to present significant challenges, particularly when the inferior petrosal sinus is thrombosed, collapsed, or angiographically invisible. In this study, we introduce facilitated retrograde access via the facial vein, which is employed in the transvenous embolization of CSDAVF with isolated superior ophthalmic venous drainage. We also present illustrative cases and technical points.

A Case of Severe Delayed Vasospasm after Clipping Surgery for an Unruptured Intracranial Aneurysm.

Delayed ischemic stroke associated with intractable vasospasm after clipping of unruptured intracranial aneurysms (UIAs) has been rarely reported. We report a patient with delayed ischemic stroke associated with intractable vasospasm following UIA clipping. A middle-aged female underwent surgery for unruptured middle cerebral artery bifurcation aneurysms. The patient tolerated the neurosurgical procedure well. Seven days postoperatively, the headache was unbearable; a postcraniotomy headache persisted and abruptly presented with global aphasia and right-sided hemiplegia after a nap. Emergency digital subtraction angiography showed severe luminal narrowing with segmental vasoconstriction, consistent with severe vasospasm. The patient's neurological deficit improved after chemical angioplasty. Neurosurgeons should pay close attention to this treatable/preventive entity after neurological deterioration following UIA clipping, even in patients without subarachnoid hemorrhage.

Predicting outcomes of unruptured intracranial artery dissection with clear symptoms onset using clinical and radiological features.

We investigated the clinical and radiologic predictors of unruptured symptomatic intracranial artery dissection (IAD) outcomes. Unruptured symptomatic IAD patients who underwent vessel wall magnetic resonance imaging (VW-MRI) and time-of-flight magnetic resonance angiography (TOF-MRA) within 1 month after symptom onset, followed for over 12 months were included. Baseline features predicting the clinical outcome of recurrent symptoms and radiologic outcomes of aneurysmal dilatation and occlusion were analyzed using logistic regression analysis. The Kaplan-Meier method calculated the median time to morphological stability. Patients with aneurysmal dilatation were categorized into progressive and non-progressive enlargement subgroups. Seventy-three IADs from 65 patients were included. All patients showed benign clinical course (mRS 0-1). No baseline features were predictive of recurrent symptoms. Aneurysmal dilatation was associated with increased outer diameter in baseline VW-MRI (OR, 23.15; 95% CI, 3.78-141.75, P < 0.001) and TOF-MRA (OR, 10.81; 95% CI, 2.16-53.99, P = 0.004). Occlusion was inversely associated with preserved patency in baseline VW-MRI (OR, 0.1; 95% CI, 0.01-0.74, P = 0.024) and TOF-MRA (OR, 0.14; 95% CI, 0.02-0.98; P = 0.048). The median time to morphological stability was 3.9 months (95% CI, 3.16-5.5). While baseline features did not significantly differ between aneurysmal dilatation subgroups, follow-up imaging revealed significant differences in remodeling index, normalized wall index, relative signal intensity of intramural hematoma, and presence of onion-skin appearance and intramural hematoma (all P < 0.05). Our findings suggest that while unruptured IAD presents a benign clinical outcome, follow-up imaging may be necessary to monitor the progressive enlargement of aneurysmal dilatation.

Impact of Patient Head Posture on Lens Radiation Exposure During Cerebral Angiography.

BACKGROUND AND PURPOSE: Cerebral angiography remains crucial for detailed characterization and preoperative assessments for intracranial aneurysm. Despite its diagnostic importance, cerebral angiography poses challenges due to its invasiveness, the risk of neurological complications, and radiation exposure. To investigate the impact of head posture on lens radiation exposure during cerebral angiography, this study focused on the correlation between radiation doses to the eye lens, head flexion angles, and head size. MATERIALS AND METHODS: A retrospective analysis was performed on 20 patients who underwent cerebral angiography for unruptured intracranial aneurysms between October and November 2022. Radiation doses to the lens, which were measured in a prior prospective study using photoluminescent glass dosimeters, were analyzed alongside head flexion angles, anteroposterior (AP) head diameters, and kerma-area product (KAP) to evaluate their correlation with lens radiation exposure. The lateral radiation source is located on the left side of the patients. RESULTS: The cohort consisted of 20 patients (60% female, mean age: 62.3 ± 9.9 years). The radiation dose to the left eye (the eye closer to the x-ray source) was 2.8 times higher than that to the right eye (9.18 ± 3.31 mGy vs. 3.3 ± 0.60 mGy, P < 0.001). A strong positive correlation was observed between the left eye lens dose and head flexion angle (R = 0.815, P < 0.001). While the AP head diameter significantly correlated with the flexion angle, it showed no significant correlation with lens dose. The KAP was inversely correlated with both the left lens dose (R = -0.597, P = 0.005) and the flexion angle (R = -0.689, P < 0.001). CONCLUSIONS: Our findings underscore the significant impact of head posture on lens radiation exposure during cerebral angiography. Adjusting head positioning may provide a practical approach to reduce radiation exposure to the lens. Furthermore, it is worth noting that the left lens received more radiation than the right, likely due to the X-ray source being on the left side of the patient. ABBREVIATIONS: AP = anteroposterior; KAP = kerma-area product, PLD = photoluminescent glass dosimeter.

Diagnosis of Unruptured Intracranial Aneurysms Using Proton-Density Magnetic Resonance Angiography: A Comparison With High-Resolution Time-of-Flight Magnetic Resonance Angiography.

OBJECTIVE: Differentiating intracranial aneurysms from normal variants using CT angiography (CTA) or MR angiography (MRA) poses significant challenges. This study aimed to evaluate the efficacy of proton-density MRA (PD-MRA) compared to high-resolution time-of-flight MRA (HR-MRA) in diagnosing aneurysms among patients with indeterminate findings on conventional CTA or MRA. MATERIALS AND METHODS: In this retrospective analysis, we included patients who underwent both PD-MRA and HR-MRA from August 2020 to July 2022 to assess lesions deemed indeterminate on prior conventional CTA or MRA examinations. Three experienced neuroradiologists independently reviewed the lesions using HR-MRA and PD-MRA with reconstructed voxel sizes of 0.253 mm3 or 0.23 mm3, respectively. A neurointerventionist established the gold standard with digital subtraction angiography. We compared the performance of HR-MRA, PD-MRA (0.253-mm3 voxel), and PD-MRA (0.23-mm3 voxel) in diagnosing aneurysms, both per lesion and per patient. The Fleiss kappa statistic was used to calculate inter-reader agreement. RESULTS: The study involved 109 patients (average age 57.4 ± 11.0 years; male:female ratio, 11:98) with 141 indeterminate lesions. Of these, 78 lesions (55.3%) in 69 patients were confirmed as aneurysms by the reference standard. PD-MRA (0.253-mm3 voxel) exhibited significantly higher per-lesion diagnostic performance compared to HR-MRA across all three readers: sensitivity ranged from 87.2%-91.0% versus 66.7%-70.5%; specificity from 93.7%-96.8% versus 58.7%-68.3%; and accuracy from 90.8%-92.9% versus 63.8%-69.5% (P ≤ 0.003). Furthermore, PD-MRA (0.253-mm3 voxel) demonstrated significantly superior per-patient specificity and accuracy compared to HR-MRA across all evaluators (P ≤ 0.013). The diagnostic accuracy of PD-MRA (0.23-mm3 voxel) surpassed that of HR-MRA and was comparable to PD-MRA (0.253-mm3 voxel). The kappa values for inter-reader agreements were significantly higher in PD-MRA (0.820-0.938) than in HR-MRA (0.447-0.510). CONCLUSION: PD-MRA outperformed HR-MRA in diagnostic accuracy and demonstrated almost perfect inter-reader consistency in identifying intracranial aneurysms among patients with lesions initially indeterminate on CTA or MRA.

In Vitro Head-to-Head Comparison of Flow Reduction between Fibered and Non-Fibered Pushable Coils.

PURPOSE: To compare the embolization effects of a non-fibered pushable coil with a conventional fibered pushable coil in an in vitro bench-top experiment. MATERIALS AND METHODS: A simplified vascular phantom with 4 channels (1 for the non-fibered coil, 1 for the fibered coil, and 2 for continuous circuit flow) was used. A single coil of the longest length was inserted to evaluate the effect of single-coil embolization, and 3 consecutive coils were inserted to assess the effect of multiple-coil embolization. Post-embolization angiography was performed to obtain flow variables (time to peak [TTP], relative peak intensity [rPI], and angiographic flow reduction score [AFRS]) from time density curves. The packing densities of the two coil types were calculated, and the AFRS of each channel was determined by dividing the TTP by the rPI. RESULTS: When inserting a single coil, the conventional fibered coil demonstrated better flow reduction, as indicated by a higher AFRS (25.6 vs. 17.4, P=0.034). However, the non-fibered coil exhibited a significantly higher packing density (12.9 vs. 2.4, P=0.001). Similar trends were observed with multiple coils. CONCLUSION: The conventional fibered pushable coil showed better flow reduction efficiency, while the non-fibered pushable coil had a higher packing density, likely due to the flexibility of the coil loops. A better understanding of the distinct characteristics of different pushable coils can enhance the outcomes of various vascular embolization.

Effect of Intravenous Thrombolysis Prior to Mechanical Thrombectomy According to the Location of M1 Occlusion.

BACKGROUND AND PURPOSE: The additive effects of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remain unclear. We aimed to investigate the efficacy and safety of IVT prior to MT depending on the location of M1 occlusion. METHODS: We reviewed the cases of patients who underwent MT for emergent large-vessel occlusion of the M1 segment. Baseline characteristics as well as clinical and periprocedural variables were compared according to the location of M1 occlusion (i.e., proximal and distal M1 occlusion). The main outcome was the achievement of functional independence (modified Rankin Scale score, 0-2) at 3 months after stroke. The main outcomes were compared between the proximal and distal groups based on the use of IVT before MT. RESULTS: Among 271 patients (proximal occlusion, 44.6%; distal occlusion, 55.4%), 33.9% (41/121) with proximal occlusion and 24.7% (37/150) with distal occlusion underwent IVT prior to MT. Largeartery atherosclerosis was more common in patients with proximal M1 occlusion; cardioembolism was more common in those with distal M1 occlusion. In patients with proximal M1 occlusion, there was no association between IVT before MT and functional independence. In contrast, there was a significant association between the use of IVT prior to MT (odds ratio=5.30, 95% confidence interval=1.56-18.05, P=0.007) and functional independence in patients with distal M1 occlusion. CONCLUSION: IVT before MT was associated with improved functional outcomes in patients with M1 occlusion, especially in those with distal M1 occlusion but not in those with proximal M1 occlusion.

Association Between the Timing of Atrial Fibrillation Detection and Functional Outcome Following Mechanical Thrombectomy.

BACKGROUND: Atrial fibrillation detected after stroke (AFDAS) refers to the identification of newly diagnosed atrial fibrillation (AF) following an ischemic stroke in patients without known AF (KAF). The objective of this study was to compare the functional outcomes of patients diagnosed with AFDAS and those with KAF who underwent mechanical thrombectomy. METHODS AND RESULTS: We conducted a retrospective analysis of patients who underwent mechanical thrombectomy and with either new AF diagnosed during hospitalization or KAF. We compared the baseline characteristics, clinical, and procedure-related variables between those with AFDAS and KAF. The primary outcome was the achievement of functional independence, defined as a modified Rankin Scale score of 0 to 2, at 3 months after stroke. Of the 252 patients, 101 (40.1%) were classified into the AFDAS group. The KAF group exhibited a higher rate of stroke history compared with the AFDAS group (32.5% versus 13.9%; P=0.001). Tandem occlusion was more common in the KAF group (13.2% versus 5.9%), while M2 occlusion was more common in the AFDAS group (11.3% versus 20.8%). The proportion of patients who achieved functional independence was higher in the AFDAS group (37.7% versus 52.5%; P=0.029). Multivariable analysis showed that AFDAS was associated with a favorable functional outcome (odds ratio, 2.67 [95% CI, 1.39-5.14]; P=0.003). CONCLUSIONS: AFDAS demonstrated a positive association with functional independence in patients with stroke who underwent mechanical thrombectomy and were finally diagnosed to have AF during hospitalization. The observed disparities in occlusion site, intractable thrombus, and history of previous stroke may have contributed to these findings.

Distal normal vessel diameter might be associated with silent brain infarcts after stenting for symptomatic carotid stenosis.

BACKGROUND: Carotid artery stenting (CAS) has been the standard treatment for carotid stenosis because it is less invasive; however, the risk of periprocedural thromboembolism is high. We investigated the predictors for silent brain infarcts (SBIs), focusing on embolic protection in CAS. METHODS: This study was single-center retrospective study, and we obtained baseline demographics and clinical, laboratory, and periprocedural variables of patients who underwent CAS. Also, methods used for embolic protection (no EPD, distal EPD, or proximal balloon guiding catheter) during CAS were obtained. Distal normal vessel diameter was defined as the diameter of cervical internal carotid artery where the artery wall becomes parallel. Diffusion-weighted imaging was performed before and after procedure to detect SBIs. The primary outcome was stented territory SBIs, and the secondary outcomes were any territories SBIs and stented territory SBIs in cases with EPD. RESULTS: A total of 196 CAS procedures with mean age 69.1 ± 9.9 years were included. After CAS, stented territory SBIs occurred in 53 (27.0 %) cases and any territories SBIs in 60 (30.6 %) cases. Univariable analyses revealed that distal normal vessel diameter (odds ratio = 1.71, 95 % confidence interval = 1.20-2.43, P = 0.003) was associated with the occurrence of stented territory SBIs after CAS. After adjusting for potential variables, larger distal normal vessel diameter (1.61 [1.10-2.36], P = 0.014) increased the occurrence of SBIs after CAS. Consistent results were obtained when the outcome was any territories SBIs or stented territory SBIs in cases with EPD. CONCLUSIONS: Distal normal vessel diameter was a predictor for the occurrence of SBI after CAS. The passable pore size of EPDs may vary depending on vessel diameter, and may impact the occurrence of SBIs.

Ruptured Medullary Hemangioblastoma Mimicking a Craniocervical Junction Dural Arteriovenous Fistula with a Pseudoaneurysm.

Hemangioblastomas (HBMs) are rare vascular tumors commonly located in the posterior fossa of adults. A mid-50s patient presented with sudden unconsciousness. Computed tomography scans revealed acute hemorrhages around the posterior fossa, predominantly in the subarachnoid space. Digital subtraction angiography (DSA) revealed an 8-mm round lesion filled with contrast agent, fed by the C1 segmental artery of the left vertebral artery (VA), showing early venous drainage to the spinal cord and brainstem. Emergent embolization was attempted under suspicion of a ruptured dural arteriovenous fistula, resulting in parent artery occlusion due to feeder selection failure. Follow-up DSA after a month depicted a persistent aneurysm via collaterals from both VAs. Consequently, the decision was made to proceed with surgical intervention, leading to the resection of the lesion, confirming its diagnosis as a HBM through histological examination. This case underscores the potential for misdiagnosis when HBMs with an intratumoral shunt mimic vascular shunt lesions.

The influence of contralateral circulation on computational fluid dynamics of intracranial arteries: simulated versus measured flow velocities.

BACKGROUND: This study aimed to retrospectively evaluate the influence of contralateral anterior circulation on computational fluid dynamics (CFD) of intracranial arteries, by comparing the CFD values of flow velocities in unilateral anterior circulation with the measured values from phase-contrast magnetic resonance angiography (PC-MRA). METHODS: We analyzed 21 unilateral anterior circulation models without proximal stenosis from 15 patients who performed both time-of-flight MRA (TOF-MRA) and PC-MRA. CFD was performed with the inflow boundary condition of a pulsatile flow of the internal carotid artery (ICA) obtained from PC-MRA. The outflow boundary condition was given as atmospheric pressure. Simulated flow velocities of the middle cerebral artery (MCA) and anterior cerebral artery (ACA) from CFD were compared with the measured values from PC-MRA. RESULTS: The velocities of MCA were shown to be more accurately simulated on CFD than those of ACA (Spearman correlation coefficient 0.773 and 0.282, respectively). In four models with severe stenosis or occlusion of the contralateral ICA, the CFD values of ACA velocities were significantly lower (< 50%) than those measured with PC-MRA. ACA velocities were relatively accurately simulated in the models including similar diameters of both ACAs. CONCLUSION: It may be necessary to consider the flow condition of the contralateral anterior circulation in CFD of intracranial arteries, especially in the ACA. RELEVANCE STATEMENT: Incorporating the flow conditions of the contralateral circulation is of clinical importance for an accurate prediction of a rupture risk in Acom aneurysms as the bidirectional flow and accurate velocity of both ACAs can significantly impact the CFD results. KEY POINTS: • CFD simulations using unilateral vascular models were relatively accurate for MCA. • Contralateral ICA steno-occlusion resulted in an underestimation of CFD velocity in ACA. • Contralateral flow may need to be considered in CFD simulations of ACA.

Flow Diverter Treatment Using a Flow Re-Direction Endoluminal Device for Unruptured Intracranial Vertebral Artery Dissecting Aneurysm: Single-Center Case Series and Technical Considerations.

PURPOSE: This study aimed to evaluate the effectiveness, safety, and technical considerations of flow diverter (FD) treatment using a Flow Re-direction Endoluminal Device (FRED) for unruptured intracranial vertebral artery dissecting aneurysms (VADAs). MATERIALS AND METHODS: We conducted a retrospective study of 23 patients with unruptured intracranial VADAs who underwent FD treatment using a FRED between June 2017 and August 2021. Symptoms, imaging findings, treatment strategies, and angiographic and clinical outcomes were evaluated. Dissections were categorized according to the dominance of the VA in which they occurred: dominant VA, co-dominant VA, and non-dominant VA. RESULTS: All patients successfully underwent FD treatment with either a FRED (n=11) or FRED Jr. (n=12). Complete occlusion rates were 78.3% at 6-month follow-up magnetic resonance angiography and 91.3% at 12-month. There were no instances of complications, recurrence, or retreatment during a median follow-up of 20 months. Dissections occurred in the dominant VA in 3 cases (13.0%), the co-dominant VA in 13 cases (56.5%), and the non-dominant VA in 7 cases (30.4%). Intimal flap and true lumen stenosis were observed in 39.1% and 30.4% of cases, respectively. Four cases required a bilateral VA approach due to technical difficulties, all in the non-dominant VA. CONCLUSION: Flow diversion treatment using a FRED for unruptured intracranial VADAs proved feasible and safe, yielding satisfactory occlusion rates. Technical challenges were more likely in lesions involving non-dominant VAs in the acute or subacute stage, mainly due to associated intraluminal lesions compromising the arterial lumen.