Endovascular therapy versus best medical care for acute ischemic stroke with distal medium vessel occlusion: a systematic review and meta-analysis

BACKGROUND

With the refinement of catheter technology, distal medium vessel occlusions (DMVOs) are now viewed as amenable to endovascular treatment (EVT) but its efficacy and safety remains unclear in AIS patients with DMVO.

METHODS

We conducted a systematic search of PubMed, Embase databases and Cochrane Library up to December 2023 using keywords to identify studies comparing EVT versus BMT in AIS with DMVOs. The assessed clinical outcomes were excellent functional outcome, good functional outcome, 90-day mortality, symptomatic intracranial hemorrhage (sICH), and early neurological improvement (ENI) after treatment.

RESULTS

Overall, 31 studies were included. There were no significant differences in excellent functional outcome (OR: 1.21, 95% CI: 0.99-1.47), good functional outcome (OR: 1.03, 95% CI: 0.82-1.30) and 90-day mortality (OR: 1.17, 95% CI: 0.84-1.62). Additionally, EVT led to higher sICH (OR: 1.64, 95% CI: 1.09-2.47) and better ENI (OR: 1.50, 95% CI: 1.02-2.19) compared to BMT. In individuals with M2 occlusion receiving EVT showed better excellent functional outcomes (OR: 1.48, 95% CI: 1.07-2.03). Those patients with PCA occlusion showed no significant difference in functional outcomes. In individuals with ACA occlusion, EVT resulted in reduced functional independence (OR: 0.55, 95% CI: 0.31-0.98). For NIHSS < 6, BMT achieved better functional independence compared to EVT (OR: 0.71, 95% CI: 0.51-0.98) and EVT showed higher sICH (OR: 3.44, 95% CI: 1.42-8.31).

CONCLUSION

For patients with AIS and DMVO occlusion, EVT fails to improve functional prognosis while increasing sICH incidence. More randomized controlled trials are needed in the future to confirm these results.

Persistence of the hypoglossal artery: A rare case report

The persistence of the hypoglossal artery is a rare embryonic vascular variant in which a transient connection between the carotid and vertebrobasilar systems fails to regress. Typically asymptomatic and incidentally discovered on imaging, this condition can alter cerebral blood flow and increase the risk of vascular complications such as aneurysms, strokes, and arteriovenous malformations. We present the case of a 70-year-old female with no prior medical history who was admitted to the emergency department with right-sided hemiparesis. A cerebral CT angiography, performed to evaluate for acute ischemic stroke and potential thrombolysis, revealed a persistent hypoglossal artery arising from the internal carotid artery at the C1-C2 level and connecting to the basilar artery through the hypoglossal canal. This case highlights the importance of recognizing this rare anatomical variant on imaging to prevent misinterpretation and avoid complications during surgical or endovascular interventions at the skull base.

Effect of the aspect ratio and wall heterogeneities on the mechanical behaviour of the aneurysm wall: Experimental investigation on phantom arteries

The management of unruptured intracranial aneurysms (UIA) involves assessing the risk of rupture, which requires a thorough understanding of risk factors such as the geometric characteristics of the neck (neck size) or local structural heterogeneities. This study explores the impact of neck size on the rupture risk of the aneurysmal sac and examines how local heterogeneities, such as calcifications or variations in tissue composition, influence the mechanical response of the wall of a saccular aneurysm during the insertion of an innovative arterial wall deformation device (DDP). The results reveal that high aspect ratios (AR) are associated with increased hemodynamic stress, thereby raising the risk of rupture. Additionally, this study provides valuable insights into the complex relationship between tissue heterogeneity, especially calcifications, and the mechanical response of aneurysm walls to mechanical stimuli. It appears that local heterogeneities weaken the integrity of the arterial wall, thus increasing the potential for rupture. Finally, although the DDP is not intended to treat intracranial aneurysms (IA), it could prove to be a relevant tool for deepening the understanding of their rupture mechanisms.

Fast aberration correction in 3D transcranial photoacoustic computed tomography via a learning-based image reconstruction method

Transcranial photoacoustic computed tomography (PACT) holds significant potential as a neuroimaging modality. However, compensating for skull-induced aberrations in reconstructed images remains a challenge. Although optimization-based image reconstruction methods (OBRMs) can account for the relevant wave physics, they are computationally demanding and generally require accurate estimates of the skull's viscoelastic parameters. To circumvent these issues, a learning-based image reconstruction method was investigated for three-dimensional (3D) transcranial PACT. The method was systematically assessed in virtual imaging studies that involved stochastic 3D numerical head phantoms and applied to experimental data acquired by use of a physical head phantom that involved a human skull. The results demonstrated that the learning-based method yielded accurate images and exhibited robustness to errors in the assumed skull properties, while substantially reducing computational times compared to an OBRM. To the best of our knowledge, this is the first demonstration of a learned image reconstruction method for 3D transcranial PACT.

A silent malformation: Closed spinal dysraphism in a boy with urinary incontinence

Spinal dysraphisms (SDs) are characterized by a heterogeneous range of congenital spinal anomalies  that arise from derivative disturbances in neural tube development. Closed spinal dysraphism, a variant, is less common and typically has a subtle clinical presentation. Timely and correct diagnosis is essential to avert chronic complications. We describe a 12-year-old boy who presented with progressively worsening bladder and bowel incontinence since early childhood. On clinical examination, he was found to have swelling of the sacral region, gross motor impairment, and a slim physique. MRI showed hydro/syringomyelia, tethered cord, lipomeningocele, spina bifida in the sacral region, chronic cystitis and dural ectasia. These test results were consistent with the diagnosis of closed spinal dysraphism. This case highlights the need to consider urinary incontinence and sacral anomalies as manifestations of closed spinal dysraphism. Neuroimaging plays a key role in diagnosis, and especially MRI is the gold standard in detecting detailed structural abnormalities. To improve patient outcomes and quality of life, this paper emphasizes the intricacy of closed spinal dysraphism and the necessity of multidisciplinary management and early intervention.

Preoperative MR - based model for predicting prognosis in patients with intracranial extraventricular ependymoma

Objectives

To develop and validate a prediction model based on brain MRI features to predict disease-free survival (DFS) and overall survival (OS) for patients with intracranial extraventricular ependymoma (IEE).

Methods

The study included 114 patients with pathology-proven IEE, of whom 80 were randomly assigned to a training group and 34 to a validation group. Preoperative brain MRI images were assessed with the Visually AcceSAble Rembrandt Images (VASARI) feature set. Clinical variables were assessed including age, gender, KPS, pathological grade of the tumor and blood test data such as eosinophil, blood urea nitrogen and serum creatinine. Multivariate Cox proportional hazards regression analysis was performed to select the independent prognostic factors for DFS and OS. Three prediction models were built with clinical variables, MRI-VASARI features, and combined clinical and MRI-VASARI data, respectively. The predictive power of survival models was assessed using c-index and calibration curve.

Results

Clinical variables such as eosinophil, blood urea nitrogen and serum creatinine, and MRI-VASARI feature for definition of the non-enhancing margin (F13) were significantly correlated with the prognosis of DFS. Blood urea nitrogen, D-dimer, tumor location (F1), eloquent brain (F3), and T1/FLAIR ratio (F10) were independent predictors of OS. Based on these factors, prediction models were constructed. The concordance indices of the three survival models for OS were 0.732, 0.729, and 0.768, respectively. For DFS, the concordance indices were respectively 0.694, 0.576, and 0.714.

Conclusion

Predictive modelling combining both clinical and MRI-VASARI features is robust and may assist in the assessment of prognosis in patients with IEE.

Brain age prediction based on brain region volume modeling under broad network field of view

BACKGROUND AND OBJECTIVE

Brain region volume from Structural Magnetic Resonance Imaging (sMRI) can directly reflect abnormal states in brain aging. While promising for clinical brain health assessment, existing volume-based brain age prediction methods fail to explore both linear and nonlinear relationships, resulting in weak representation and suboptimal estimates.

METHODS

This paper proposes a brain age prediction method, RFBLSO, based on Random Forest (RF), Broad Learning System (BLS), and Leave-One-Out Cross Validation (LOO). Firstly, RF is used to eliminate redundant brain regions with low correlation to the target value. The objective function is constructed by integrating feature nodes, enhancement nodes, and optimal regularization parameters. Subsequently, the pseudo-inverse method is employed to solve for the output coefficients, which facilitates a more accurate representation of the linear and nonlinear relationships between volume features and brain age.

RESULTS

Across various datasets, RFBLSO demonstrates the capability to formulate brain age prediction models, achieving a Mean Absolute Error (MAE) of 4.60 years within the Healthy Group and 4.98 years within the Chinese2020 dataset. In the Clinical Group, RFBLSO achieves measurement and effective differentiation among Healthy Controls (HC), Mild Cognitive Impairment (MCI), and Alzheimer's disease (AD) (MAE for HC, MCI, and AD: 4.46 years, 8.77 years, 13.67 years; the effect size η2 of the analysis of variance for AD/MCI vs. HC is 0.23; the effect sizes of post-hoc tests are Cohen's d = 0.74 (AD vs. MCI), 1.50 (AD vs. HC), 0.77 (MCI vs. HC)). Compared to other linear or nonlinear brain age prediction methods, RFBLSO offers more accurate measurements and effectively distinguishes between Clinical Groups. This is because RFBLSO can simultaneously explore both linear and nonlinear relationships between brain region volume and brain age.

CONCLUSION

The proposed RFBLSO effectively represents both linear and nonlinear relationships between brain region volume and brain age, allowing for more accurate individual brain age estimation. This provides a feasible method for predicting the risk of neurodegenerative diseases.

Dl-3-n-Butylphthalide enhances the survival of rat bone marrow stem cells via a reactive oxygen species mediated Erk1/2 signaling pathway

Survival of bone marrow stem cells (BMSCs) is crucial for successful bone marrow transplantation. However, the underlying molecular mechanisms remain inadequately understood. Our previous research has demonstrated that dl-3-n-butylphthalide (NBP) can protect rat BMSCs (rBMSCs) from cell death via its antioxidative properties and by activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. The findings suggest that the PI3K/Akt pathway may be one of the primary targets through which NBP exert its protective effects. In this study, we explored an additional signaling pathway to further elucidate the molecular mechanisms involved in NBP-mediated protection against oxidative stress injury in rBMSCs. Oxidative stress was induced in rBMSCs using hydrogen peroxide (H2O2), imitating the cerebral ischemia microenvironment surrounding transplanted cells in vitro. The protective effects of NBP on rBMSCs against apoptosis were observed, achieving by decreasing the level of reduce reactive oxygen species (ROS) and malondialdehyde (MDA) while simultaneously increasing the concentration of superoxide dismutase (SOD). Notably, these protective effects were partially inhibited by U0126, an extracellular signal-regulated kinase1/2 (Erk1/2) inhibitor, which enhanced the suppression of NBP's antiapoptotic effects. Our results indicated that NBP could protect rBMSCs from apoptosis through modulation of ROS/Erk pathways. Further investigations are warranted to clarify the unknown mechanisms.

Plasma lipidome and intracranial aneurysms: A univariable and multivariable Mendelian randomization study

BACKGROUND

Recent studies suggest that plasma lipids, including lipoproteins and fatty acids, may contribute to the pathogenesis of intracranial aneurysms (IAs). However, the relationship between a broader range of plasma lipids and IA risk remains unclear. This study uses the Mendelian randomization (MR) approach to explore the causal relationships between 179 plasma lipids and the risk of IAs.

METHODS

We used summary statistics from a study of 7174 individuals to examine 179 plasma lipids. Data on IAs and aneurysmal subarachnoid hemorrhage (aSAH) were drawn from a study by Bakker MK et al., which included 2070 cases of unruptured IAs, 5 140 cases of aSAH, and 71,934 controls. MR analyses were conducted using inverse variance-weighted as the primary method, with weighted median, weighted mode, and MR-Egger as additional methods. To prioritize lipid risk factors, we applied multivariable Mendelian randomization-Bayesian model averaging.

RESULTS

We identified 5 plasma lipids associated with IAs and 4 with aSAH. Phosphatidylcholine (14:0_18:2) was significantly associated with both IAs and aSAH, with odds ratios of 1.44 (95 % confidence interval [CI] 1.17-1.77, Padjusted = 0.036) for IAs and 1.53 (95 % CI 1.20-1.94, Padjusted = 0.036) for aSAH. In multivariable MR, phosphatidylcholine (14:0_18:2) and phosphatidylcholine (18:0_20:3) emerged as the strongest risk factors for IAs and aSAH, respectively.

CONCLUSION

Our study identifies specific plasma lipids, particularly phosphatidylcholine (14:0_18:2) and phosphatidylcholine (18:0_20:3), as significant risk factors for IAs and aSAH. These findings suggest that phosphatidylcholines could serve as predictive biomarkers for aneurysm risk. Further research is needed to validate these associations and clarify the underlying mechanisms.

Long-term prognostic value of Rotterdam computed tomography score in traumatic brain injury after decompressive craniectomy

OBJECTIVE

Decompressive craniectomy (DC) is a critical intervention for traumatic brain injury (TBI) patients with intracranial hypertension. However, outcomes following the procedure can display considerable variability. While the Rotterdam computed tomography (CT) score was conceived to predict TBI prognosis, its utility in gauging long-term outcomes after DC remains unexplored. This study aimed to elucidate the long-term prognostic value of the Rotterdam CT score in TBI patients undergoing DC.

METHODS

This retrospective study enrolled 176 patients who underwent DC for TBI, with a follow-up of at least 12 months. The pre-DC CT scans were scored by the Rotterdam CT classification. Glasgow Outcome Scale (GOS) at the end of follow-up served as the primary outcome measure. Unfavorable outcome was defined by a GOS score of 1-3. We adjusted for known predictors of outcomes post-TBI through a multivariable logistic regression analysis.

RESULTS

Among the 176 patients, the mean follow-up period was 70.90 ± 73.04 months. Of these, 116 patients survived their hospital stay, with a mean follow-up duration of 106.91 ± 65.42 (12-209) months. Higher Rotterdam CT scores were directly associated with higher rates of unfavorable outcomes. After multivariate regression adjustments, the predictive effect of the Rotterdam CT score on unfavorable outcomes is statistically significant (odds ratio: 1.57, 95 % confidence interval: 1.00-2.46, p = 0.048).

CONCLUSION

The Rotterdam CT score demonstrates significant long-term prognostic value following DC for TBI. By methodically evaluating injury patterns using CT scans, this score addresses the existing limitations in tools assessing clinical severity.

Carotid plaque CTA analysis in patients with initial and recurrent ischemic stroke

OBJECTIVES

Recurrent ischemic stroke leads to prolonged hospital stays, deterioration in functional outcomes, increased disability and mortality rates. The composition of plaques is closely related to the occurrence of stroke. Our aim was to explore differences in carotid plaque characteristics between patients with initial and recurrent ischemic stroke.

METHODS

A retrospective study was conducted on 208 anterior circulation stroke patients who had completed head and neck CT angiography (CTA) examinations. Patients were divided into initial cerebral infarction (ICI) group and recurrent cerebral infarction (RCI) group according to clinical and imaging data. The histological and morphological characteristics of the plaques were assessed by using VascuCAP software. The general demographic data, plaque characteristics, and serological indicators were compared between the two groups. Then, the association between plaque characteristics were investigated. To investigate the contribution of plaque characteristics for predicting the risk of stroke recurrence, we have constructed multivariate logistic regression models with plaque characteristics and blood lipid level parameters.

RESULTS

There were significant differences in total carotid plaque volume (P = 0.002) between the ICI and RCI groups. The volume and percentage of Intraplaque Hemorrhage (IPH) and calcification (CALC) in the RCI group were significantly higher than those in the ICI group (P < 0.05). There were also statistically significant differences in IPH volume (P=＜0.001)and IPH percentage (P＜0.001)between the symptomatic and asymptomatic sides in the RCI group. In the ICI group, the difference in the maximum stenosis of the carotid artery lumen was statistically significant between the 2 sides (P = 0.025). The total cholesterol (P = 0.024) and triglyceride levels (P = 0.049) was significantly larger in the ICI group than in the RCI group. Further, there is a significant negative correlation between the volumes and percentages of IPH and CALC in the ICI group (volume, r = -0.225, P = 0.021; percentage, r = -0.293, P = 0.002). In addition, IPH volume and percentage were independent predictors in the logistic model with combined features of plaque volume, plaque percentage and blood lipid level (AUC = 0.755, 95 %CI 0.690-0.820).

CONCLUSION

The volume of total carotid plaque and IPH were significantly different between the ICI group and RCI group. The IPH volume and percentage on the symptomatic side of the RCI group were higher than those on the asymptomatic side. IPH has important indicative significance in identifying patients at risk of recurrent stroke.

ABBREVIATIONS

CTA, computed tomography angiography; ICI, initial cerebral infarction; RCI, recurrent cerebral infarction; IPH, intraplaque hemorrhage; CALC, calcification; AUC, area under the curve; CI, confidence interval.

Deep learning radiomic nomogram outperforms the clinical model in distinguishing intracranial solitary fibrous tumors from angiomatous meningiomas and can predict patient prognosis

OBJECTIVES

To evaluate the value of a magnetic resonance imaging (MRI)-based deep learning radiomic nomogram (DLRN) for distinguishing intracranial solitary fibrous tumors (ISFTs) from angiomatous meningioma (AMs) and predicting overall survival (OS) for ISFT patients.

METHODS

In total, 1090 patients from Beijing Tiantan Hospital, Capital Medical University, and 131 from Lanzhou University Second Hospital were categorized as primary cohort (PC) and external validation cohort (EVC), respectively. An MRI-based DLRN was developed in PC to distinguish ISFTs from AMs. We validated the DLRN and compared it with a clinical model (CM) in EVC. In total, 149 ISFT patients were followed up. We carried out Cox regression analysis on DLRN score, clinical characteristics, and histological stratification. Besides, we evaluated the association between independent risk factors and OS in the follow-up patients using Kaplan-Meier curves.

RESULTS

The DLRN outperformed CM in distinguishing ISFTs from AMs (area under the curve [95% confidence interval (CI)]: 0.86 [0.84-0.88] for DLRN and 0.70 [0.67-0.72] for CM, p < 0.001) in EVC. Patients with high DLRN score [per 1 increase; hazard ratio (HR) 1.079, 95% CI: 1.009-1.147, p = 0.019] and subtotal resection (STR) [per 1 increase; HR 2.573, 95% CI: 1.337-4.932, p = 0.004] were associated with a shorter OS. A statistically significant difference in OS existed between the high and low DLRN score groups with a cutoff value of 12.19 (p < 0.001). There is also a difference in OS between total excision (GTR) and STR groups (p < 0.001).

CONCLUSION

The proposed DLRN outperforms the CM in distinguishing ISFTs from AMs and can predict OS for ISFT patients.

CLINICAL RELEVANCE STATEMENT

The proposed MRI-based deep learning radiomic nomogram outperforms the clinical model in distinguishing ISFTs from AMs and can predict OS of ISFT patients, which could guide the surgical strategy and predict prognosis for patients.

KEY POINTS

Distinguishing ISFTs from AMs based on conventional radiological signs is challenging. The DLRN outperformed the CM in our study. The DLRN can predict OS for ISFT patients.

Feasibility of deep learning algorithm in diagnosing lumbar central canal stenosis using abdominal CT

OBJECTIVE

To develop a deep learning algorithm for diagnosing lumbar central canal stenosis (LCCS) using abdominal CT (ACT) and lumbar spine CT (LCT).

MATERIALS AND METHODS

This retrospective study involved 109 patients undergoing LCTs and ACTs between January 2014 and July 2021. The dural sac on CT images was manually segmented and classified as normal or stenosed (dural sac cross-sectional area ≥ 100 mm2 or < 100 mm2, respectively). A deep learning model based on U-Net architecture was developed to automatically segment the dural sac and classify the central canal stenosis. The classification performance of the model was compared on a testing set (990 images from 9 patients). The accuracy, sensitivity, and specificity of automatic segmentation were quantitatively evaluated by comparing its Dice similarity coefficient (DSC) and intraclass correlation coefficient (ICC) with those of manual segmentation.

RESULTS

In total, 990 CT images from nine patients (mean age ± standard deviation, 77 ± 7 years; six men) were evaluated. The algorithm achieved high segmentation performance with a DSC of 0.85 ± 0.10 and ICC of 0.82 (95% confidence interval [CI]: 0.80,0.85). The ICC between ACTs and LCTs on the deep learning algorithm was 0.89 (95%CI: 0.87,0.91). The accuracy of the algorithm in diagnosing LCCS with dichotomous classification was 84%(95%CI: 0.82,0.86). In dataset analysis, the accuracy of ACTs and LCTs was 85%(95%CI: 0.82,0.88) and 83%(95%CI: 0.79,0.86), respectively. The model showed better accuracy for ACT than LCT.

CONCLUSION

The deep learning algorithm automatically diagnosed LCCS on LCTs and ACTs. ACT had a diagnostic performance for LCCS comparable to that of LCT.

Efficacy and safety of surpass evolve flow diverters: A systematic review and meta-analysis

OBJECTIVE

To provide cumulative evidence on the safety and efficacy of the Surpass Evolve Flow Diverters (SE-FDs) in treating intracranial aneurysms.

METHODS

PubMed, Scopus, Embase, and Web of Science were searched until May, 2024. The primary efficacy endpoint was complete occlusion rate, and the safety endpoints included rate of different complications and mortality. Data is pooled and reported with 95 % confidence intervals (CIs) using random-effect models. A meta-regression analysis was performed to assess the potential effects of confounding factors on study endpoints.

RESULTS

Eleven studies with 690 patients and 757 aneurysms were included. There was moderate risk of bias in all studies. With a median follow-up of 243 days, the complete occlusion rate was 67.1 % (95 %CI: 57.3-75.5 %, I2=72 %), with no difference between ruptured and unruptured aneurysms (p = 0.97). Stent stenosis was the most frequent complication which occurred in 18.2 % (95 %CI: 10.3-30.1 %, I2=71 %) of aneurysms at a median follow-up of 306 days. The rate of thromboembolic complications was 6.6 % (95 %CI: 3.8-11 %, I2=50 %), including ischemic stroke in 1.9 % (95 %CI: 1.1-3.4 %, I2=0 %) of patients. Device-related mortality rate was 0.5 % (95 %CI: 0.2-1.5 %, I2=0 %). Meta-regression showed that diameter of aneurysm was significantly associated with complete occlusion rate (coefficient: - 0.11, p < 0.001).

CONCLUSIONS

SE-FD is effective for treating intracranial aneurysms, with moderate efficacy compared to other devices and an acceptable rate of complications. Larger aneurysm size predicts lower occlusion rates. The lack of controlled trials warrants further research to explore the efficacy and safety of SE-FDs in clinical practice.

Effect of Sequential Repetitive Transcranial Magnetic Stimulation With Bilateral Arm Training on the Brain Effective Connectivity in Chronic Stroke

This study investigated the effects of combining repetitive transcranial magnetic stimulation (rTMS) with bilateral arm training (BAT) on effective brain connectivity in chronic stroke patients using functional near-infrared spectroscopy. Fifteen post-stroke patients and fifteen healthy individuals were enrolled. Coupling function analysis was performed to evaluate the effective connectivity inflow, outflow, and the dominant information flow (DIF) during standalone BAT and combined rTMS-BAT therapy. Significant task-related alterations were observed in the ipsilesional supplementary motor area and occipital lobe (OL) of stroke patients undergoing rTMS-BAT. During BAT, stroke patients exhibited more pronounced DIF from the OL to motor areas compared to healthy controls. Furthermore, in the rTMS-BAT condition, patients demonstrated enhanced DIF from the ipsilesional OL and contralesional prefrontal cortex to ipsilesional motor areas. These findings suggested a potential synergistic effect on cortical reorganization through the sequential combination of task-related training and TMS in chronic stroke patients, offering insights into rehabilitation strategies.

SARM1 deletion inhibits astrogliosis and BBB damage through Jagged-1/Notch-1/NF-κB signaling to improve neurological function after ischemic stroke

Reactive astrogliosis is a critical process in the development of ischemic stroke. However, the precise mechanism by which reactive astrogliosis changes the pathogenesis of ischemic stroke remains elusive. Sterile alpha and TIR motif-containing 1 protein (SARM1) plays a key role in axonal degeneration and is involved in different cell death programs that regulate neuronal survival. The present study investigated the role of SARM1 in regulating reactive astrogliosis and neurological function after stroke in whole-body SARM1 knockout (SARM1-/-) mice. SARM1-/- mice showed significantly smaller infarction, slighter apoptosis, and fewer neurological function deficits 1-7 days after ischemic injury. Immunohistochemistry, western blot, and real-time PCR analyses revealed that compared with the wild-type (WT) mice, SARM1-/- mice exhibited reduced astrocytic proliferation, increased anti-inflammatory astrocytes, decreased glial scar formation in the infarct zone on day 7 after ischemic injury. SARM1 deletion also suppressed cerebral microvascular damage and blood-brain barrier (BBB) injury in ischemic brains. Mechanistically, SARM1 deletion inhibited the stroke-triggered activation of NF-κB signaling and decreased the expression of Jagged-1 and NICD in astrocytes. Overall, these findings provide the first line of evidence for a causative role of SARM1 protein in ischemia-induced reactive astrogliosis and ischemic neurovascular damage.

Optimization of shoulder synthetic MRI through post-processing and comparison with conventional MRI

PURPOSE

To evaluate the utility of synthetic MRI of the shoulder compared with conventional MRI and to optimize the parameters of morphological images through post-processing. Additionally, we aimed to assess the agreement of T2 values between multi-echo spin-echo (MESE) and multi-dynamic multi-echo (MDME) sequences.

METHODS

Twenty healthy volunteers underwent shoulder MRI. The optimal post-processing parameters for the tendon-muscle contrast were examined using synthetic MRI, and two radiologists analyzed three image sets: conventional images, synthetic images using preset parameters, and optimized images. Qualitative analysis included assessment of the visibility of anatomical structures, overall image quality, and magic angle effect, whereas the quantitative analysis included measurement of the relative signal intensity and relative contrast. The T2 values of the articular cartilage and supraspinatus muscle were measured for each sequence.

RESULTS

Images synthesized with short echo times and long repetition times showed high tendon-muscle contrast. For fat-suppressed T2-weighted images, conventional images showed the highest image quality (p < 0.001), whereas the optimized images achieved comparable visibility of the rotator cuff (p = 0.031-1.0). No significant differences were observed among image sets in proton density-weighted images and T1-weighted images (p > 0.05). The T2 values of the MDME sequence were consistent with those of the MESE sequence at the muscle (p = 0.81), but were approximately 8.3 ms longer at the cartilage (p < 0.001).

CONCLUSIONS

Synthetic MRI provided acceptable image quality using appropriate post-processing parameters. The simultaneous acquisition of multiple morphological images and quantitative maps within five minutes holds promise for shoulder examination.

Multi-delay arterial spin labeling using a variable repetition time scheme in Moyamoya disease: Comparison with single-delay arterial spin labeling

PURPOSE

To present a multi-delay arterial spin labeling (ASL) protocol that obtains the cerebral blood flow (CBF) considering the arterial transit time (ATT), and to assess the correlations with an iodine-123-N-isopropyl-p-iodoamphetamine single-photon emission computed tomography (123I-IMP SPECT) reference standard between multi-delay ASL and single-delay ASL in patients with Moyamoya disease.

METHOD

We retrospectively analyzed the images of 23 patients with Moyamoya disease (4-73 years, 5 men, 18 women), each of whom was imaged with 10-delay ASL using the variable repetition time (TR) scheme, single-delay ASL, and SPECT. Pearson correlation coefficients were calculated between the CBF values of each ASL and SPECT in the three divisions of the ATT, which we categorized as fast, normal, and slow regions. The threshold for statistical significance was set atP<0.05.

RESULTS

The CBF measured by multi-delay ASL and single-delay ASL were positively correlated with that measured by SPECT, with correlation coefficients of 0.6701 and 0.5637, respectively (P < 0.001). In the fast, normal, and slow ATT divisions, the correlation coefficients between the CBF measured by multi-delay ASL and that measured by SPECT were 0.6745, 0.7055, and 0.6746, respectively. Similarly, the correlations between the CBF measured by single-delay ASL and that measured by SPECT were 0.3811, 0.5090 and 0.6178, respectively.

CONCLUSIONS

Multi-delay ASL using the variable TR scheme showed a higher correlation with 123I-IMP SPECT than single-delay ASL for measuring the CBF. The variable TR scheme potentially improved the quantification of CBF on ASL imaging.

Enhancing prediction of parenchymal hemorrhage type 2 after endovascular treatment in acute ischemic stroke using dual-phase CTA

OBJECTIVE

To evaluate the effectiveness of dual-phase CT angiography (CTA) in predicting parenchymal hemorrhage type 2 (PH2) following endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS).

METHODS

A retrospective analysis was conducted across two centers, including 232 AIS patients who underwent EVT. Three predictive models were developed: a clinical model (Model C), a clinical model incorporating single-phase CTA data (Model CS), and a clinical model incorporating dual-phase CTA data (Model CD). The performance of these models in predicting PH2 occurrence post-EVT was assessed and compared.

RESULTS

The model incorporating dual-phase CTA data (Model CD) demonstrated superior predictive performance, with higher area under the curve (AUC) values in both training and validation datasets, compared to Models C and CS. Calibration and decision curve analyses further confirmed the enhanced accuracy and clinical utility of Model CD.

CONCLUSION

The findings indicate that dual-phase CTA provides a more accurate assessment of collateral circulation compared to single-phase CTA, thereby improving the prediction of PH2 after EVT. This enhanced predictive capability can assist clinicians in making more informed decisions regarding AIS management.

Effects of sleep on the glymphatic functioning and multimodal human brain network affecting memory in older adults

Understanding how sleep affects the glymphatic system and human brain networks is crucial for elucidating the neurophysiological mechanism underpinning aging-related memory declines. We analyzed a multimodal dataset collected through magnetic resonance imaging (MRI) and polysomnographic recording from 72 older adults. A proxy of the glymphatic functioning was obtained from the Diffusion Tensor Image Analysis along the Perivascular Space (DTI-ALPS) index. Structural and functional brain networks were constructed based on MRI data, and coupling between the two networks (SC-FC coupling) was also calculated. Correlation analyses revealed that DTI-ALPS was negatively correlated with sleep quality measures [e.g., Pittsburgh Sleep Quality Index (PSQI) and apnea-hypopnea index]. Regarding human brain networks, DTI-ALPS was associated with the strength of both functional connectivity (FC) and structural connectivity (SC) involving regions such as the middle temporal gyrus and parahippocampal gyrus, as well as with the SC-FC coupling of rich-club connections. Furthermore, we found that DTI-ALPS positively mediated the association between sleep quality and rich-club SC-FC coupling. The rich-club SC-FC coupling further mediated the association between DTI-ALPS and memory function in good sleepers but not in poor sleepers. The results suggest a disrupted glymphatic-brain relationship in poor sleepers, which underlies memory decline. Our findings add important evidence that sleep quality affects cognitive health through the underlying neural relationships and the interplay between the glymphatic system and multimodal brain networks.

The temporal-insula type of temporal plus epilepsy patients with different postoperative seizure outcomes have different cerebral blood flow patterns

PURPOSE

This study retrospectively analyzed preoperative arterial spin labeling (ASL) perfusion MRI data of patients with the temporal-insula type of temporal plus epilepsy (TI-TPE). We aimed to investigate the differences in presurgical cerebral blood flow (CBF) changes in TI-TPE patients with different surgical outcomes.

METHOD

A total of 48 TI-TPE patients confirmed by SEEG were meticulously reviewed for this study. Patients were divided into the seizure-free (SF) group (Engel IA) and the non-seizure-free (NSF) group (Engel IB to IV) according to the Engel seizure classification. The 3D-ASL data of all patients before surgery were analyzed using statistical parametric mapping (SPM) and graph theory analysis. These findings were then compared to healthy controls (HC) based on whole-brain voxel-level analysis and covariance network analysis.

RESULT

At the voxel-level, both SF and NSF groups showed significantly decreased CBF in the ipsilateral transverse temporal gyrus and insula (TTG/insula), contralateral middle cingulate gyrus, precuneus (MCG/precuneus), and increased CBF in the ipsilateral superior temporal gyrus and the superior temporal pole (STG/STP). Wherein the SF group showed more lower CBF in the contralateral MCG/precuneus, with unique increased CBF in the contralateral STG/insula and decreased CBF in the contralateral calcarine as well. In terms of network attributes, the NSF group showed a significantly higher clustering coefficient (Cp), global efficiency (Eglob), local efficiency (Eloc), shorter shortest path length (Lp), and more extensive abnormal nodes compared to the SF and HC groups. While the SF group has higher synchronicity than the HC group.

CONCLUSION

Both SF and NSF groups had abnormal CBF changes at the voxel and network levels with different patterns. The SF group showed more obvious regional CBF changes, while the NSF group showed more extended network disruption, which might underlie different seizure outcomes after local surgical resection.

Residual inflammatory risk is associated with leukoaraiosis in patients with ischemic stroke

OBJECTIVE

Emerging evidence has highlighted the clinical significance of residual inflammation risk (RIR) in cardiovascular and cerebrovascular diseases, with studies demonstrating its association with disease recurrence and poor prognosis. This study aimed to investigate the relationship between RIR and leukoaraiosis (LA) severity in patients with ischemic stroke.

METHODS

In this observational cohort study, we classified patients into four groups based on low-density lipoprotein cholesterol (LDL-C) and high-sensitivity C-reactive protein (hsCRP) levels: RIR (LDL-C < 2.6 mmol/L and hsCRP ≥ 2 mg/L), residual cholesterol risk (RCR) (LDL-C ≥ 2.6 mmol/L and hsCRP < 2 mg/L), both risk or residual cholesterol and inflammatory risk (RCIR) (LDL-C ≥ 2.6 mmol/L and hsCRP ≥ 2 mg/L) and neither risk (LDL-C < 2.6 mmol/L and hsCRP < 2 mg/L). LA presence and severity were assessed using magnetic resonance imaging (MRI) and graded according to the Fazekas scale. Ordinal logistic regression analyses were performed to evaluate the association between RIR and LA severity.

RESULTS

Among 643 enrolled patients, 413 (64.2 %) exhibited LA. The distribution of patients across RIR, RCR, RCIR, and neither risk groups was 28.9 %, 19.8 %, 20.4 %, and 30.9 %, respectively. Comparative analysis revealed that LA patients exhibited significantly higher age (P < 0.001), elevated BMI (P < 0.001), increased hypertension prevalence (P = 0.004), greater RIR proportion (P < 0.001), and higher smoking rates (P = 0.007) compared to non-LA counterparts. Ordinal logistic regression analysis demonstrated that RIR (OR 1.447, 95 % CI 1.044-1.851, P < 0.001) was independently associated with the severity of LA after adjusting for multiple confounding variables. Subgroup analysis stratified by BMI further revealed that RIR (OR 2.994, 95 % CI 2.259-3.730, P < 0.001) was significantly correlated with LA severity in patients with a BMI ≥ 25.0.

CONCLUSIONS

These findings suggest that RIR may serve as an independent risk factor for LA in patients with ischemic stroke, particularly among those with a BMI ≥25.0.

Novel classification of brain vascular tortuosity measures: A systematic review

Given the absence of a standardized measure for evaluating tortuosity in cerebrovascular images, our investigation focuses on the methods used to estimate vascular tortuosity over the past decade. The main purpose is to create a useful, easily accessible guide to tortuosity estimation methods for brain researchers and clinicians. We conducted a systematic literature review in PUBMED and Scopus from 2013 to 2023 for tortuosity index (TI) analysis of human cerebrovascular images providing either quantitative or qualitative tortuosity measures. A total of 111 articles reporting TI measures were identified, in which 16 different TI were used to analyze 29 different diseases in Magnetic Resonance Angiography (MRA), Computed Tomography Angiography (CTA), Digital Subtraction Angiography (DSA), Ultrasound images (US), and other Magnetic Resonance Imaging (MRI) sequences. A novel categorization of tortuosity indices is suggested, based on the nature of the metrics. This classification comprises four categories: morphological-based, ratio distance-based, trigonometrical-based, and curvature-based methods. A TI Metric guide is proposed to facilitate the selection of the optimal TI for each use case. Our results show that Distance Metric (DM) is the most used, simple, and versatile method of capturing tortuous patterns, making it a preferred choice among researchers studying different disease contexts. Conversely, healthcare practitioners often prefer the Weibel and Fields tortuosity metric due to its categorical output, which offers a simplified and readily interpretable classification that complements clinical decision-making processes effectively.

The current state of forensic imaging - post mortem imaging

Over the last few decades, forensic imaging has become an essential part of current forensic practice. The aim of this 4-part review is to provide a comprehensive overview of forensic imaging over the first 25 years of this century. After a brief historic review, this first part details the advantages and limitations of post-mortem imaging for the indications most frequently encountered in daily practice.

Neuropathologic Features and Underlying Medical Disease States of Spontaneous Subdural Hematomas in Adults: A Hospital Autopsy Case Series From a Single Tertiary Center

CONTEXT.—

Spontaneous (nontraumatic) subdural hematomas (SDHs) have been reported yet have not been well studied.

OBJECTIVE.—

To identify the neuropathologic features of acute spontaneous SDHs (ASSDHs) and their associated medical conditions.

DESIGN.—

A retrospective study of 235 autopsy cases of SDH was conducted. Review of demographics, underlying medical conditions, and coagulation profile as well as gross and histopathologic examination of the brain and other organs were performed.

RESULTS.—

Among the 32 cases of ASSDH, 5 cases (15.6%) had severe hemorrhage and 4 (12.5%) demonstrated brain herniation. Twenty-two cases (68.8%) had concurrent but nonconnecting subarachnoid hemorrhage or intraparenchymal hemorrhage. The most common underlying medical condition was thrombocytopenia (n = 21; 65.6%), followed by immunosuppression (n = 15; 46.9), bloodstream infections or sepsis (n = 12; 37.5%), hypertension (n = 13; 40.6%), and coronary artery disease (n = 12; 37.5%). Many patients with thrombocytopenia or immunosuppression had underlying malignancies, with leukemia being the most common type (n = 11; 34.4%). The use of circulatory devices or hemodialysis was noted in a significant portion of ASSDH cases. In terms of coagulation factors, most of our ASSDH patients had normal prothrombin time and activated partial thromboplastin time, but abnormal platelet count and D-dimer levels.

CONCLUSIONS.—

ASSDHs can be severe and are often associated with subarachnoid hemorrhage and/or intraparenchymal hemorrhage. The causes of ASSDH are limited to certain underlying medical conditions that ultimately lead to bleeding tendency. Autopsies are helpful in determining the etiology. Given their association with abnormal platelet count, correcting platelet deficiencies is a potential preventive measure for ASSDHs.

Neurophysiological correlates of subjective cognitive decline in perimenopausal and postmenopausal midlife women at risk for Alzheimer's disease

OBJECTIVE

This study aimed to investigate neurophysiological correlates of subjective cognitive decline (SCD) among midlife women at risk for Alzheimer's disease (AD).

METHODS

We examined 156 cognitively normal perimenopausal and postmenopausal women aged 40 to 65 years, with an AD family history and/or apolipoprotein E epsilon 4 genotype, who were not on menopause hormone therapy. Participants underwent neuropsychological testing, health and menopausal symptom questionnaires, and brain volumetric magnetic resonance imaging, arterial spin labeling-magnetic resonance (MR) measuring cerebral blood flow, and 31 phosphorus magnetic resonance spectroscopy ( 31 P-MRS) measuring mitochondria high-energy phosphates (adenosine triphosphate [ATP], phosphocreatine [PCr], inorganic phosphate [Pi]). We used multivariable regressions to compare outcomes between participants with and without SCD and to identify the main correlates of SCD status.

RESULTS

The SCD group (n = 53) exhibited worse verbal memory and executive function test performance (multivariable adjusted P  = 0.029) compared to controls (n = 103). On brain imaging, the SCD group showed higher PCr/ATP in precuneus, posterior cingulate, and parietal regions compared to controls (multivariable adjusted P  < 0.05) and no overall differences in Pi/ATP, PCr/Pi, volume, or cerebral blood flow measures. Results were controlled for age, race, smoking status, hysterectomy status, presence of vasomotor symptoms, menopause symptom severity score, past menopause hormone therapy usage, history of depression, AD family history, and apolipoprotein E epsilon 4 status. The factors more strongly associated with SCD status were inferior parietal PCr/ATP, menopause symptom severity, and presence of vasomotor symptoms.

CONCLUSIONS

Among perimenopausal and postmenopausal midlife women, SCD was associated with altered brain mitochondria bioenergetics in some brain regions similarly affected by AD, warranting further investigation.

Analysis of risk factors for long COVID after mild COVID-19 during the Omicron wave in Japan

BACKGROUND

Post-COVID-19 syndrome, referred to as "long COVID," is characterized by persistent symptoms that develop during or after SRAS-CoV-2 infection lasting for ≥12 weeks, which cannot be explained by factors other than COVID-19. Previous studies before the Omicron pandemic have identified female sex, older age (≥50 years), severity of illness, obesity, diabetes, and smoking as risk factors for long COVID. However, data on long COVID following the emergence of the Omicron variants are limited.

METHODS

An online survey was conducted among outpatients diagnosed with mild COVID-19 at 14 participating institutions in Japan between July 30, 2022, and December 31, 2023.

RESULTS

Of the included 246 cases, 76 (35.5%) experienced at least one long COVID symptom 12 weeks after onset. Logistic regression analysis revealed that age ≥40 years was significantly associated with an increased risk of respiratory (odds ratio [OR]: 3.80, 95% confidence interval [CI]: 1.67-8.65) and neurologic symptoms (OR: 4.53, 95% CI: 1.84-11.13). Conversely, antiviral drug use was associated with a decreased risk of respiratory symptoms (OR: 0.31, 95% CI: 0.11-0.93).

CONCLUSION

Caution is warranted when treating patients over 40 years of age with mild COVID-19 due to their higher susceptibility to developing long COVID. Antiviral drugs may be beneficial in managing respiratory symptoms and mitigating disease severity.

Predictors of favorable long-term outcomes in first-line surgery for microprolactinomas

PURPOSE

Opting for first-line surgery in carefully selected patients with microprolactinomas provides the advantage of avoiding long-term dopamine agonist (DA) medication and potential associated side effects. However, the lack of comprehensive long-term data poses a challenge in identifying those patients who would benefit the most from upfront surgery. To improve guidance in the selection process for microprolactinoma patients in clinical practice, we aimed to establish simple clinical and biochemical parameters predicting non-dependence on DAs.

METHODOLOGY

Retrospective analysis of a prospectively maintained database, focusing on patients with microprolactinomas who underwent upfront surgery. We assessed clinical and biochemical risk factors for the patients' reliance on DAs at their latest follow-up using regression analysis. We next proceeded to conduct Receiver Operating Characteristic (ROC) analysis to determine the optimal threshold cutoff prolactin (PRL) level for practical application in clinical settings that best differentiates between surgical long-term remission status and long-term dependence on DAs.

RESULTS

A microadenoma was observed in 46 patients, of whom 12 (26%) exhibited long-term dependence on DAs at a median follow-up of 78 months. Baseline PRL values were significantly higher in patients with long-term DA dependence compared to those without (p = 0.05). High baseline PRL values (HR 23.9, 95% CI 1.0-593.7, p = 0.05), but not the presence of headache or male gender, were identified as independent predictors of long-term dependence on DAs. PRL thresholds for discriminating long-term DA dependence were estimated to be 290 µg/L (AUROC = 0.73, 95% CI 0.55-0.92, p = 0.03; sensitivity = 90%, specificity = 80%).

CONCLUSIONS

In patients with microprolactinomas, first-line surgery presents a favorable prospect for reducing reliance on DAs. However, for those with high PRL levels ≥ 290 µg/L at diagnosis, first-line surgery is not recommended, as the majority of them require adjuvant DA therapy in the long term.

Sleep characteristics and brain structure: A systematic review with meta-analysis

BACKGROUND

As the global population ages, the prevalence of associated conditions, including neurodegeneration and dementia, will increase. Thus, reducing risk factors is crucial to prevention. Sleep contributes to brain homeostasis and repair, which, if impaired, could lead to neurodegeneration. However, the relationship between sleep characteristics, disorders, and brain morphology is poorly understood in healthy adults. Therefore, we aimed to systematically analyse the literature and clarify how sleep characteristics are associated with brain structures.

METHODS

We systematically searched PUBMED, MEDLINE, ProQuest, Web of Science, and Scopus for empirical studies of healthy adults examining the associations between sleep characteristics or disorders and brain structure, adjusting for age, gender, and head size. We conducted a meta-analysis with random effects models for volumetric studies and a seed-based spatial analysis for voxel-based morphometry (VBM) studies.

RESULTS

One hundred and five articles (60 volumetric, 45 VBM) with 106 studies reporting 108,364 participants were included. Most studies (73.1%) found sleep characteristics and disorders to be associated with predominantly lower brain volumes (cross-sectional: 51.9% of all cross-sectional; longitudinal: 45.5% of longitudinal). In VBM studies, REM sleep behaviour disorder was linked to lower grey matter volume in the right frontal gyrus (z-score = -3.617, 68 voxels, p-value = <0 0.001).

CONCLUSION

Sleep characteristics - poor quality, short or long sleep - and sleep disorders are predominantly associated with lower brain volumes, suggesting that inadequate sleep (short, long or poor quality) might contribute to neurodegeneration. This insight highlights the importance of monitoring, managing, and enforcing sleep health to prevent or mitigate potential neurodegenerative processes.

Pearls and Pitfalls of T1-Weighted Neuroimaging: A Primer for the Clinical Radiologist

All T1-weighted images are built upon one of two fundamental pulse sequences, spin-echo and gradient echo, each of which has distinct signal characteristics and clinical applications. Moreover, within each broadly defined category of T1-weighting, acquisition parameters can be modified to affect image quality, contrast, and scan duration; each tailored sequence has unique advantages, drawbacks, clinical indications, and potential artifacts. In this review, we describe key features that distinguish different types of T1-weighted sequences and discuss the utility of each sequence for specific clinical settings, including neuro-oncology, vasculopathy, and pediatric neuroradiology. In addition, we provide case examples from our institution that illustrate common artifacts and pitfalls associated with image interpretation. The findings described herein provide a framework to individualize the imaging protocol based on patient presentation and clinical indication.

Diagnostic accuracy of imaging modalities for detection of spinal metastases: a systematic review and meta-analysis

PURPOSE

Detecting spinal metastases is highly relevant in patients with oncological disorders as it can affect the staging and treatment of their disease. We aimed to evaluate the diagnostic performance of computed tomography (CT), magnetic resonance imaging (MRI), FDG positron emission tomography (PET)/CT, bone scintigraphy (BS), and single-photon emission computed tomography (SPECT) for spinal metastases detection.

METHODS

Medline, EMBASE, and Web of Science were systematically searched until March 2024 for diagnostic accuracy studies on spinal metastases detection (PROSPERO-registration: CRD42024540139). Data extraction and quality assessment using the QUADAS-2 tool were performed by two independent reviewers. Using bivariate random effects modeling, pooled sensitivities, specificities, and diagnostic odds ratios (DOR) were calculated, and hierarchical summary operating curves were constructed.

RESULTS

Twenty-five studies (49 datasets), encompassing 3102 patients were included. Per-patient pooled sensitivities of CT, MRI, PET/CT, BS and SPECT were 70%, 93%, 82%, 75%, and 84%, respectively. Pooled specificities were 74%, 85%, 75%, 92%, and 81%, respectively. Per-lesion pooled sensitivities of CT, MRI, PET/CT, BS and SPECT were 76%, 91%, 92%, 77%, and 92%, respectively. Pooled specificities were 91%, 94%, 85%, 52%, and 86%, respectively. MRI had the highest DOR in per patient and lesion analyses.

CONCLUSION

MRI had highest diagnostic accuracy for spinal metastases detection on patient and lesion level, suggesting a broader use in addition to the routine staging CT, at least in patients at high risk and where the detection of a spinal metastasis could alter therapy decisions. Herein, results should be considered with the limitations of each modality.

Feasibility of Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in a Rabbit Model of Peritoneal Metastases: PIPALIM Project

BACKGROUND

Animal models are essential for testing new pressurized intraperitoneal aerosol chemotherapy (PIPAC) protocols; however, no immunocompetent animal model of peritoneal surface malignancies (PSMs) treated with PIPAC has been established. This study evaluated the feasibility, safety, and oncological efficacy of PIPAC in a rabbit PSM model.

METHODS

The study was conducted in two phases: (1) Feasibility Assessment: Three healthy rabbits underwent three consecutive PIPAC procedures (saline) at weekly intervals. The rabbits' well-being, morbidity, mortality, and histological changes were monitored. (2) Treatment Phase: Rabbits with PSM were treated with PIPAC using oxaliplatin, cisplatin-doxorubicin, or saline. Parameters such as animal well-being, ascites volume, morbidity, Peritoneal Cancer Index (PCI), histological response (Peritoneal Regression Grading Score [PRGS]), tumor cell proliferation/apoptosis, and circulating tumor DNA (ctDNA) levels were assessed.

RESULTS

PIPAC was feasible and safe, with no increased morbidity or mortality. PIPAC demonstrated antitumor efficacy with lower PCI (control 21.6 vs. oxaliplatin 9.2 vs. cisplatin-doxorubicin 10.2; p < 0.001), improved histological response (PRGS: control 3.38 vs. oxaliplatin 1.95 vs. cisplatin-doxorubicin 1.85; p = 0.01), and reduced tumor cell proliferation (control 5.3% vs. oxaliplatin 0.82% vs. cisplatin-doxorubicin 0.62%; p < 0.0001). ctDNA levels showed promise for monitoring treatment response, warranting further investigation.

CONCLUSION

This study confirms the feasibility and effectiveness of PIPAC with oxaliplatin or cisplatin-doxorubicin in rabbits with PSM. The model provides a foundation for future research on PIPAC protocols and related treatments.

A systematic review of application of frequency-domain optical coherence tomography in cerebral large artery atherosclerosis

AIMS

Frequency-domain optical coherence tomography (FD-OCT) is an emerging intravascular imaging modality that offers exceptional spatial resolution in interventional neuroradiology. We aimed to systematically review clinical studies on the applications of FD-OCT in cerebral large artery atherosclerosis (LAA).

METHODS

A systematic literature review of PubMed, Embase, and Cochrane Library was conducted to identify eligible studies published before 1 March, 2025. Eligible studies included all clinical articles written in English that reported the applications of FD-OCT in patients diagnosed with LAA.

RESULTS

A total of 50 studies with 1134 patients were included. FD-OCT was considered to be a feasible intravascular imaging modality as successful imaging could be achieved in 87.0% of patients with a 1.2% periprocedural complication rate. Unsuccessful FD-OCT imaging was attributed primarily to its current limitations, particularly inadequate blood clearance and failure to navigate the tortuous cerebrovascular anatomy or stenosis. The majority of the included studies (35/50) employed FD-OCT to evaluate extracranial atherosclerotic stenosis. FD-OCT could better stratify subsequent stroke risk by adequately identifying features of plaque vulnerability such as thin-cap fibroatheroma, neovascularization, and cholesterol crystal. Through accurately assessing stent-vessel interaction, FD-OCT has the potential to guide the selection of tailored interventions during carotid artery stenting. Recent research (10/50) has shown its potential utility for intracranial atherosclerotic stenosis, including culprit lesion differentiation, peri-intervention evaluation, and mechanistic insight into pathophysiology of stenosis and in-stent restenosis. As for acute ischemic stroke, FD-OCT following thrombectomy can potentially guide the selection of tailored adjunctive treatments to optimize clinical outcomes by assessing the intrinsic properties of the culprit lesion.

CONCLUSIONS

FD-OCT has emerged as a valuable intravascular imaging tool for evaluating the intrinsic properties of culprit lesions and stent-vessel interactions, showing substantial potential in the diagnosis, evaluation, and treatment of cerebral LAA.

CT perfusion enhances accuracy of intracranial occlusion detection in acute stroke: effect of specialty and experience level

PURPOSE

Detection of intracranial arterial occlusions on CT angiography (CTA) can be challenging. We studied the value of CT perfusion (CTP) for arterial occlusion detection in the anterior circulation amongst radiologists and neurologists, both experienced and less experienced.

METHODS

Seven raters reviewed CTAs of 335 acute stroke patients with and without occlusions. We evaluated occlusion detection with and without CTP. We categorized the occlusions by location. Two experienced raters exposed to all baseline and follow-up imaging defined a consensus gold standard. We calculated sensitivity, specificity and accuracy for occlusion detection with and without CTP and compared the area under the curve (AUC). We also compared the performance of radiologists versus neurologists and of experienced and less experienced raters.

RESULTS

We included 260 patients with ≥1 occlusion and 75 without occlusions. The accuracy of occlusion detection was greater with CTP assistance compared to CTA only (AUC 0.93 vs 0.91, p= 0.03 for proximal and AUC 0.88 vs 0.81, p<0.001 for distal). Distal occlusion detection accuracy improved with CTP in neurologists and in radiologists, whereas improved proximal occlusion detection accuracy was only present in neurologists. Adding CTP improved distal occlusion detection in experienced and less experienced raters. Proximal occlusion detection accuracy improved with CTP in experienced raters, and trended towards improvement in less experienced raters.

CONCLUSION

Assistance of CTP maps may improve the accuracy of intracranial occlusion detection on CTA. In this study, the benefit was most profound for distal occlusions, regardless of experience level or specialty background of the rater.

Chronic Sinusitis With Nasal Polyps and Olfactory Dysfunction: Comparing Olfactory Training and Glucocorticoid Treatment

OBJECTIVE

Few studies have compared the effectiveness of olfactory training (OT) and glucocorticoids (GC) in the phenotype of chronic sinusitis with nasal polyps (CRSwNP) with olfactory dysfunction (OD). To evaluate the effects of GC and OT on OD in patients with eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) and non-eosinophilic chronic rhinosinusitis with nasal polyps (NonECRSwNP).

METHODS

After 2 weeks of endoscopic sinus surgery, patients with a composite threshold discrimination identification score (TDIS) of less than 30.5 were randomly assigned to receive GC (n = 38), OT (n = 36), or both (n = 34). Retrospective phenotypic stratification of CRSwNP patients was performed based on whether eosinophils in the tissue exceeded 10% (ECRSwNP and NonECRSwNP). Follow-up assessments were conducted at 1, 3, and 6 months postintervention. Evaluations included TDIS, the 22-item Sino-Nasal outcome test (SNOT-22), Lund-Kennedy endoscopic scores (LKES), and the frequency of olfactory fluctuations (OF).

RESULTS

SNOT-22 and LKES improved significantly over time. At 1 month, TDIS change was higher in the GCwOT group than in the GC or OT groups. By 6 months, GCwOT remained superior to GC but not to OT. Follow-up showed no difference between GC and OT. In ECRSwNP patients, GCwOT showed greater TDIS changes at 3 and 6 months versus GC, with lower OF incidence (p < 0.0125). In NonECRSwNP, GCwOT outperformed OT only at 1 month.

CONCLUSION

GC combined with OT can reduce OF in patients with ECRSwNP and consistently enhance olfactory function.

LEVEL OF EVIDENCE: 2

TRIAL REGISTRATION

ChiCTR2100049551.

A systematic review of the Contour Neurovascular System for the treatment of intracranial aneurysms

BackgroundThis systematic review aims to reflect the current state of the literature on use and efficacy of the Contour Neurovascular System (CNS), an endovascular implant specifically developed for the treatment of intracranial wide-neck aneurysms.MethodsWe included manuscripts from a PubMed search with the terms "contour AND aneurysm." Manuscripts that did not refer to the CNS were excluded via screening.The number of interventions from included studies was calculated and, where possible, occlusion rates of aneurysms, used CNS sizes, and complications were recorded.ResultsWe found a total number of 23 studies with 625 patients and 661 aneurysms treated with CNS (122 ruptured). The number of studies with low bias and sufficient randomization is very small. Only two prospective studies with 43 patients could be identified. The mean aneurysm size was 6.4 mm (height), 5.5 mm (dome size), and 3.9 mm (neck size). Most used CNS sizes were "7" and "9." A complete occlusion result was achieved in 61% of patients in the long-term controls; in 28%, an adequate occlusion with a small neck rest was reported.ConclusionsThe preliminary results of the CNS are promising. However, these findings need to be proven in larger, prospective studies.

Clinical presentation of cytomegalovirus meningoencephalitis: a retrospective study of 12 adult patients with a variety of immunocompromised conditions

BACKGROUND

Human Cytomegalovirus (HCMV) is a crucial pathogen in immunocompromised individuals, causing infections such as pneumonitis, colitis, and retinitis. However, research on HCMV infections of the central nervous system (CNS) is limited.

OBJECTIVE

This retrospective cohort study aimed to investigate the clinical manifestations, underlying conditions, laboratory findings, imaging findings, treatments, and outcomes of adult patients diagnosed with HCMV meningitis or encephalitis at a single medical center in East Asia over a 6-year period.

METHODS

The study included patients who had positive results in quantitative polymerase chain reaction (PCR) tests of their cerebrospinal fluid (CSF) for HCMV at any time between January 2017 and December 2022. Clinical characteristics, laboratory findings, imaging findings, treatment approaches, and outcomes were reviewed and analyzed from electronic medical records.

RESULTS

The cohort comprised 12 patients with a median age of 61 years (range, 43-84 years). Stupor and generalized seizures were the most common neurological presentations. Brain imaging findings in half of the patients revealed nonspecific abnormalities, such as atrophy. CSF protein levels were elevated, with a median of 74.5 mg/dL. CSF pleocytosis was observed in three patients (25%) and was predominantly lymphocytic. The in-hospital mortality rate was 75% (9 out of 12 patients).

CONCLUSIONS

Although rare, HCMV CNS infections are associated with a high mortality rate. CSF pleocytosis is uncommon in such cases, potentially contributing to clinical misdiagnosis or underestimation. HCMV meningoencephalitis should be considered in immunocompromised patients who present with unexplained seizures or altered consciousness.

Evaluation of infrapatellar fat pad elasticity in knee osteoarthritis using IVIM-DWI-based virtual MR elastography: repeatability and reproducibility analysis

BACKGROUND

Fibrosis of the infrapatellar fat pad (IPFP) leads to changes in its stiffness, which may impact knee osteoarthritis. However, few studies have utilized virtual MR elastography to assess the variations of the IPFP. This study aimed to evaluate the value of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI)-based virtual MR elastography (vMRE) in the IPFP by assessing the test-retest repeatability, as well as intra- and inter-observer reproducibility.

METHODS

A total of 71 subjects underwent IVIM-DWI examinations, which were conducted twice with an interval of 30-60 min using an 18-channel knee coil at 3T. Shifted apparent diffusion coefficient (sADC) was calculated from two different sets of b-values (b = 200/800 sec/mm2 and 200/1500 sec/mm2) and then converted to IVIM-DWI MRI-based virtual shear modulus (μdiff_800 and μdiff_1500). Two readers independently delineated regions of interest (ROI) within the IPFP on the vMRE stiffness map to obtain the mean and standard deviation (SD) values of μdiff. Short-term test-retest repeatability, as well as intra- and inter-observer agreement were assessed using the intra-class correlation coefficient (ICC), the coefficient of variation (CoV), and Bland-Altman limits of agreement (LoA).

RESULTS

The mean and SD values of μdiff_1500, along with the mean value of μdiff_800 exhibited excellent intra- and inter-observer reproducibility agreement (ICC ≥ 0.90 and CoV ≤ 10%, P˂ 0.001). The intra- and inter-observer ICCs for the mean values of μdiff_800 were 0.917 and 0.901, respectively, while the ICCs for the SD values of μdiff_800 were 0.870 and 0.863, with CoV exceeding 10% (P˂ 0.001). The test-retest repeatability of the average value of μdiff_1500 was excellent (ICC = 0.902; CoV = 6.8%) compared to μdiff_800 (ICC = 0.877; CoV = 15.3%). Test-retest repeatability of SD for μdiff_1500 was good (ICC = 0.803; CoV = 11.5%) in comparison to SD for μdiff_800 (ICC = 0.796; CoV = 13.5%).

CONCLUSIONS

IVIM-DWI-based vMRE demonstrated significant potential as a reliable tool for measuring tissue elasticity in the IPFP, exhibiting higher repeatability for μdiff_1500 than for μdiff_800.

Quantitative study on whole brain volume in patients with obstructive sleep apnea based on synthetic magnetic resonance imaging

OBJECTIVE

To apply SyMRI to quantify whole brain volume changes in patients with varying degrees of obstructive sleep apnea (OSA).

METHODS

A total of 49 untreated adult patients diagnosed with OSA via polysomnography (PSG) at our hospital were included in this study. Among these patients, 21 were categorized into the mild-to-moderate OSA group, and 28 into the severe OSA group. Additionally, 31 healthy adults were recruited as the healthy control (HC) group. SyMRI post-processing software was used to obtain whole brain volume segmentation values.

RESULTS

In terms of the STOP-BANG questionnaire, the score of the severe OSA group was significantly higher than that of the mild-to-moderate OSA group (P < 0.05). Compared with the HC group, the mild-to-moderate OSA group and the severe OSA group exhibited a reduction in N3-stage sleep (both P < 0.05). Post-hoc multiple comparisons showed that compared with the HC group, the severe OSA group had increased GMV, BPV, and ICV, while the mild-to-moderate OSA group showed an increase in CSFV (P < 0.05). Additionally, compared with the HC group, the mild-to-moderate OSA group exhibited a decrease and the severe OSA group showed an increase in MYV (P < 0.05). Multiple comparisons of normalized volume fractions revealed that GMF, WMF, CSFF, MYF and BPVF were significantly different between the HC group and OSA groups (all P < 0.05).

CONCLUSION

The brain volume parameters generated from SyMRI can quantify the degree of brain injury in patients with OSA.

CLINICAL TRIAL NUMBER

Not applicable.

Index cases of intracranial aneurysms in autosomal dominant polycystic kidney disease: longitudinal experience from a single renal transplantation centre

BACKGROUND

The prevalence of intracranial aneurysms (ICAs) is higher in patients with autosomal dominant polycystic kidney disease (ADPKD) than in the general population. This extrarenal manifestation carries significant mortality and morbidity risks. Our study aims to estimate the prevalence of, and to characterize patients with ICA(s) among the ADPKD cohort of South Australia's statewide transplantation centre.

METHODS

A retrospective review of prospectively collected data was conducted for all patients who underwent nephrectomy/ies between 1 January 1995 and 31 December 2021. Incidences of neuroimaging and radiologically diagnosed ICAs, and the presence of risk factors including family history are compared between ADPKD patients and those with an alternate primary nephrological diagnosis (control). Descriptive statistics and a narrative review of cases are presented.

RESULTS

Seven patients had ICAs (14.3% ADPKD patients, 23.3% those with neuroimaging). Six did not meet current criteria for ICA screening, and five had no known family history of ICA. Three patients suffered aneurysmal rupture (mean age of 36). Two of these cases involved smaller ICAs. Cases demonstrated detectable vascular changes on early neuroimaging, hypoplastic anatomical variants, aneurysmal growth, de novo ICA formation, and association with other vascular abnormalities.

CONCLUSION

Early detection of ICAs and pre-aneurysmal changes should be prioritized in ADPKD. Although limited by the small study cohort, our findings are consistent with previous literature suggesting ICA ruptures occur earlier in ADPKD and in smaller aneurysms. Further investigation is required into how these ICAs behave. Nonetheless, it is vital that centres coordinate a multidisciplinary, patient-centred approach to ICA screening, surveillance, and management for ADPKD patients.

A computational ontology framework for the synthesis of multi-level pathology reports from brain MRI scans

BackgroundConvolutional neural network (CNN) based volumetry of MRI data can help differentiate Alzheimer's disease (AD) and the behavioral variant of frontotemporal dementia (bvFTD) as causes of cognitive decline and dementia. However, existing CNN-based MRI volumetry tools lack a structured hierarchical representation of brain anatomy, which would allow for aggregating regional pathological information and automated computational inference.ObjectiveDevelop a computational ontology pipeline for quantifying hierarchical pathological abnormalities and visualize summary charts for brain atrophy findings, aiding differential diagnosis.MethodsUsing FastSurfer, we segmented brain regions and measured volume and cortical thickness from MRI scans pooled across multiple cohorts (N = 3433; ADNI, AIBL, DELCODE, DESCRIBE, EDSD, and NIFD), including healthy controls, prodromal and clinical AD cases, and bvFTD cases. Employing the Web Ontology Language (OWL), we built a semantic model encoding hierarchical anatomical information. Additionally, we created summary visualizations based on sunburst plots for visual inspection of the information stored in the ontology.ResultsOur computational framework dynamically estimated and aggregated regional pathological deviations across different levels of neuroanatomy abstraction. The disease similarity index derived from the volumetric and cortical thickness deviations achieved an AUC of 0.88 for separating AD and bvFTD, which was also reflected by distinct atrophy profile visualizations.ConclusionsThe proposed automated pipeline facilitates visual comparison of atrophy profiles across various disease types and stages. It provides a generalizable computational framework for summarizing pathologic findings, potentially enhancing the physicians' ability to evaluate brain pathologies robustly and interpretably.

Current Landscape of Short-T2 Imaging Techniques in the Musculoskeletal System: The Past, Present and Future

Conventional MRI is limited in imaging tissues with short T2 relaxation times, such as bone, ligaments, and cartilage, due to their rapid signal decay. This limitation has spurred the development of specialized MRI techniques designed specifically for short-T2 tissue imaging. Traditional pulse sequences, including three-dimensional gradient echo (3D-GRE), susceptibility-weighted imaging (SWI), and Fast Field Echo Resembling a CT using Restricted Echo-Spacing (FRACTURE), initially addressed some of these challenges but often lacked sufficient resolution or contrast differentiation. Recent advancements, such as ultrashort echo time (UTE), zero echo time (ZTE), 3D-Bone, and synthetic computed tomography (sCT), have significantly enhanced the diagnostic capabilities of MRI by providing high-quality, CT-like visualization without exposure to ionizing radiation. These innovations have substantially improved MRI's ability to depict bone morphology, assess joint pathology, identify subtle fractures, and characterize bone tumors with higher accuracy. Beyond musculoskeletal applications, these techniques have demonstrated emerging clinical utility in additional domains, including pulmonary and dental imaging. This review article evaluates conventional pulse sequences alongside emerging MRI innovations, highlighting their clinical applications, current limitations, and technical considerations. Continued optimization of these techniques promises broader clinical adoption, potentially reducing dependence on invasive and radiation-intensive imaging modalities. Evidence Level: N/A Technical Efficacy: Stage 3.

Clinic-radiological classification of herpesviral encephalitis in humans (systematic review)

The development of a comprehensive classification for herpesvirus encephalitis remains an urgent task. Distinct clinic-radiological forms of herpesvirus cerebral lesions have been characterized, including findings from histopathological studies. Differences among these forms have been demonstrated concerning key clinical and paraclinical parameters. The presented classification identifies several distinct forms of herpesvirus encephalitis: temporal, brainstem, limbic, diencephalic encephalitis, rhombencephalitis, leukoencephalitis, ventriculoencephalitis, diffuse glial micronodular encephalitis, subcortical and cortical encephalitis, cerebellitis, neonatal encephalitis. Additionally, the concepts of combined, coexisting and multimodal lesions are introduced to describe complex forms of herpesvirus neuroinfections. The use of the term "specific spectrum of herpesvirus cerebral lesions" is supported. Both the phenomena of specificity and universality are considered. Fundamental differences between the forms of herpesvirus encephalitis are highlighted with respect to their prevalence within the population, etiological factors, clinical manifestations, typical complications, recovery completeness, mortality rates, immune status. The distinctive diagnostic and therapeutic approaches required for each form of herpesvirus encephalitis are emphasized. The integration of this classification into clinical practice has the potential to optimize medical care for patients with herpesvirus encephalitis, enabling not only etiologically-oriented but also form-specific approaches to treatment.

A Prospective Study on Hemodynamics of Combined Bypass Surgery in the Treatment of Moyamoya Disease

OBJECTIVE

The study investigates the clinical effectiveness and prognosis of selecting recipient vessels for moyamoya disease (MMD) treatment during combined bypass surgery, focusing on hemodynamic criteria.

METHODS

Ninety-six MMD patients were randomly assigned to 3 groups (A, B, C) of 32 each, undergoing combined bypass surgery. Group A selected the vessel with the fastest fluorescing in the surgical field, group B the slowest, and group C used traditional methods. The authors monitored intraoperative recipient vessel pressure, cerebral blood flow (CBF), and modified Rankin scale (mRS) scores pre-surgery and post-surgery, and compared clinical symptom improvement, stroke recurrence, CBF, and mRS during a 6-month follow-up.

RESULTS

Postoperatively, groups A and B had significantly higher recipient vessel pressures than group C, with group B showing the highest (P<0.05). CBF increased significantly in all groups at 7 days post-surgery and at 6 months, with groups A and B outperforming C, and group B showing the highest increase at 7 days (P<0.05). mRS scores decreased significantly, with groups A and B showing lower scores than C at 6 months (P<0.05). However, group B had a higher incidence of clinical symptoms post-surgery compared with A and C (P<0.05).

CONCLUSION

The study demonstrates that hemodynamic-based recipient vessel selection significantly improves clinical outcomes in MMD patients undergoing combined bypass surgery. Although group B showed the best hemodynamic results, it also had a higher incidence of immediate postoperative symptoms, suggesting a need for a balanced approach to optimize both short-term and long-term patient outcomes.

Meta-analysis of arterial spin labeling MRI to identify residual cerebral arteriovenous malformations after treatment

BACKGROUND

To use of statistical methods to assess the diagnostic value of arterial spin labeling (ASL) imaging for follow-up of treated arteriovenous malformations.

METHODS

We screened references from four databases, namely, the Cochrane Library, PubMed, Web of Science and Embase, that met the requirements. The methodology quality of the included studies was evaluated using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) tool. Data pertaining to diagnostic performance were extracted, and the pooled sensitivity and specificity were calculated using a bivariate mixed-effects model.

RESULTS

We included six studies with a total of 132 patients with arteriovenous malformation (AVM). The merged sensitivity and specificity of ASL for the diagnosis of brain AVMs with incomplete occlusion after treatment were 0.94[0.86-0.98] and 0.99 [0.59-1.00], respectively. According to the SROC curve summary, the AUC was found to be 0.98 [0.96-0.99]. No significant publication bias was observed.

CONCLUSION

While ASL does not currently match the diagnostic precision of DSA, it is instrumental in post-treatment surveillance of AVM patients. With the development of ASL technology in the future, this technique holds promise as a minimally invasive diagnostic strategy for AVMs with fewer side effects.

REGISTRATION NUMBER OF PROSPERO

CRD42023422087.

CLINICAL TRIAL NUMBER

Not applicable.

Feasibility of U-Net model for cerebral arteries segmentation with low-dose computed tomography angiographic images with pre-processing methods

Subtraction computed tomography angiography (sCTA) can effectively separate enhanced cerebral arteries from similar signal intensity and proximity (i.e., vertebrae and skull). However, sCTA is not considered mainstream because of the high radiation dose generated by the two-scan protocol. We aimed to solve the overexposure problem by training a U-Net-based CA segmentation model using a low-dose computed tomographic angiography (CTA) image-based dataset with various pre-processing methods to achieve a performance similar to that of sCTA. We optimized a non-local means (NLM) algorithm using the coefficient of variation and contrast-to-noise ratio. In addition, datasets were constructed by predicting the CA mask using a semiautomatic thresholding technique based on region growing method. Then, CTA images of 35 (2052 slices), 4 (248 slices), and 5 patients (594 slices) were used, respectively, for the train, validation, and test sets. To evaluate the performance of the U-Net-based CA segmentation model quantitatively according to the constructed dataset, the average precision (AP), intersection over union (IoU), and F1-score were calculated. For the dataset to which both the optimized NLM algorithm and semiautomatic thresholding technique were applied, the segmentation model showed the most improved performance. In particular, the quantitative evaluation of the low-dose CTA image with the NLM algorithm and the semiautomatic thresholding-based U-Net model calculated AP, IoU, and F1-scores of approximately 0.880, 0.955, and 0.809, respectively, which were most similar to the CA segmentation performance of the sCTA technique. The proposed U-Net model provided CA segmentation results without additional radiation exposure. In addition, the selection and optimization of an appropriate pre-processing methods were identified as essential for achieving higher segmentation performance for the U-Net model.

Quantitative Ischemic Lesions of Portable Low-Field Strength MRI Using Deep Learning-Based Super-Resolution

BACKGROUND

Deep learning-based synthetic super-resolution magnetic resonance imaging (SynthMRI) may improve the quantitative lesion performance of portable low-field strength magnetic resonance imaging (LF-MRI). The aim of this study is to evaluate whether SynthMRI improves the diagnostic performance of LF-MRI in assessing ischemic lesions.

METHODS

We retrospectively included 178 stroke patients and 104 healthy controls with both LF-MRI and high-field strength magnetic resonance imaging (HF-MRI) examinations. Using HF-MRI as the ground truth, the deep learning-based super-resolution framework (SCUNet) was pretrained using large-scale open-source data sets to generate SynthMRI images from LF-MRI images. Participants were split into a training set (64.2%) to fine-tune the pretrained SCUNet, and a testing set (35.8%) to evaluate the performance of SynthMRI. Sensitivity and specificity of LF-MRI and SynthMRI were assessed. Agreement with HF-MRI for Alberta Stroke Program Early Computed Tomography Score in the anterior and posterior circulation (diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score and diffusion-weighted imaging-posterior circulation Alberta Stroke Program Early Computed Tomography Score) was evaluated using intraclass correlation coefficients (ICCs). Agreement with HF-MRI for lesion volume and mean apparent diffusion coefficient (ADC) within lesions was assessed using both ICCs and Pearson correlation coefficients.

RESULTS

SynthMRI demonstrated significantly higher sensitivity and specificity than LF-MRI (89.0% [83.3%-94.6%] versus 77.1% [69.5%-84.7%]; P<0.001 and 91.3% [84.7%-98.0%] versus 71.0% [60.3%-81.7%]; P<0.001, respectively). The ICCs of diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score between SynthMRI and HF-MRI were also better than that between LF-MRI and HF-MRI (0.952 [0.920-0.972] versus 0.797 [0.678-0.876], P<0.001). For lesion volume and mean apparent diffusion coefficient within lesions, SynthMRI showed significantly higher agreement (P<0.001) with HF-MRI (ICC>0.85, r>0.78) than LF-MRI (ICC>0.45, r>0.35). Furthermore, for lesions during various poststroke phases, SynthMRI exhibited significantly higher agreement with HF-MRI than LF-MRI during the early hyperacute and subacute phases.

CONCLUSIONS

SynthMRI demonstrates high agreement with HF-MRI in detecting and quantifying ischemic lesions and is better than LF-MRI, particularly for lesions during the early hyperacute and subacute phases.

A Systematic Review and Meta-Analysis on the Safety of Antiplatelet Discontinuation Following Stent-Assisted Coil Embolization for Cerebral Aneurysms

BACKGROUND

Stent-assisted coil embolization (SACE) is a common endovascular technique for managing intracranial aneurysms. The permanent presence of a stent inside the cerebral artery necessitates the postoperative use of antiplatelets. However, a consensus about how long to continue on it remains debated. This systematic review aims to discuss and quantify the risk of ischemic complications after antiplatelet discontinuation following SACE.

METHODS

PubMed, Cochrane Library, Scopus, and Web of Science (WOS) were systematically searched for studies assessing the outcomes after antiplatelet discontinuation following SACE for cerebral aneurysms. The primary outcome was the odds of ischemic complications after antiplatelet discontinuation. Using a random-effects model, the pooled event rate, along with a 95% confidence interval (CI), was calculated. The Comprehensive Meta-Analysis software (CMA) software was used for the analysis. The Newcastle-Ottawa Scale (NOS) was used for the quality assessment.

RESULTS

A total of five observational cohort studies were included in this systematic review. The studies recruited cases from 2009 and 2020, predominantly in Korea and Japan. Data from 18,425 cases obtained from four studies were analyzed. The duration of antiplatelet therapy varied widely across the included studies. Additionally, most studies reported a median follow-up of 24 months or more after antiplatelet discontinuation. We extracted and analyzed the odds of thromboembolic complications occurring within 6 to 24 months after the discontinuation of antiplatelets. The pooled rate of thromboembolism after antiplatelet discontinuation in this meta-analysis was 0.01 (95% CI: 0.006 to 0.018).

CONCLUSION

This review demonstrates that the risk of thromboembolic complications after discontinuing antiplatelet therapy post-SACE is low. However, no strong consensus exists on the ideal duration for maintaining dual- or single-antiplatelet therapy. Further prospective studies with longer follow-ups are warranted to clarify the optimal durations needed to balance thromboembolic risk with hemorrhagic complications.

Distal protection of endovascular recanalization for symptomatic non-acute occlusion of vertebrobasilar artery

PURPOSE

The research aimed to investigate the safety and efficacy of distal protection of endovascular recanalization for symptomatic non-acute occlusion of the intracranial vertebrobasilar artery.

METHODS

8 consecutive patients with symptomatic non-acute VBA from April 2023 to April 2024 who underwent endovascular recanalization were retrospectively analyzed.

RESULTS

8 patients (median age 56 years; mean pretreatment National Institutes of Health Stroke Scale (NIHSS) score 6; 87.5% male) presenting with recurrent transient ischemic attacks(TIAs) (n = 1) or strokes (n = 23) were treated from April 2023 to April 2024. Median time from symptoms onset to treatment was 21 days(range: 10-43). Median time from occlusion confirmed to treatment was 13 days(range:8-26). Among the 8 patients, 8 (100%) achieved successful recanalization. The rate of periprocedural complications was 25%(2/8). Periprocedural complication included one asymptomatic intracranial hemorrhage(asICH) and thrombus translocation. The median follow-up time was 9 months (range: 6-12), with no stroke or TIA. At 90 days, there were one death (unrelated to the procedure) and 75% patients with an available modified Rankin Scale (mRS) score achieved a good outcome (mRS score of 0-2).

CONCLUSION

The distal protection of stent retriever for endovascular recanalization for symptomatic non-acute occlusion of VBA is technically safe and may decrease procedure-related complications.

Impaired glymphatic function in autoimmune glial fibrillary acidic protein astrocytopathy: a prospective analysis

BACKGROUND

To evaluate the glymphatic dysfunction and its association with disease severity in autoimmune glial fibrillary acidic protein astrocytopathy (A-GFAP-A) patients, and to determine its clinical predictors.

METHODS

A total of 20 A-GFAP-A patients and 20 healthy controls (HC) were included. All participants underwent magnetic resonance imaging, and glymphatic function was assessed using the diffusion tensor imaging along the perivascular space (DTI-ALPS) index. Modified Rankin Scale (mRS) scores were recorded at baseline and 4 weeks post-immunotherapy. Multiple linear regression analysis was conducted to identify independent predictors of short-term prognosis.

RESULTS

The baseline DTI-ALPS index was significantly lower in A-GFAP-A patients compared to HC (mean ± SD: 1.50 ± 0.06 vs. 1.62 ± 0.04 [CI -0.16, -0.08], p = 0.003), after adjusting for confounding factors. Four weeks after immunotherapy, the DTI-ALPS index significantly increased (mean ± SD: 1.52 ± 0.14 vs. 1.59 ± 0.17 [CI 0.01, 0.14], p = 0.037). A significant negative correlation was observed between the residuals of the baseline DTI-ALPS index and the baseline mRS scores (r = -0.50 [CI -0.77, -0.07], p = 0.025). The baseline DTI-ALPS index was identified as an independent predictor of short-term prognosis (coefficient = -3.43 [CI -6.68, -0.04], p = 0.048).

CONCLUSIONS

This study indicates that A-GFAP-A patients exhibit significant glymphatic dysfunction, as detected by the DTI-ALPS index, which is related to the severity of the disease. The DTI-ALPS index may serve as a biomarker for monitoring disease progression and as a predictor of short-term prognosis in A-GFAP-A patients.