Radiomics-Based Prediction of Collateral Status from CT Angiography of Patients Following a Large Vessel Occlusion Stroke.

BACKGROUND: A major driver of individual variation in long-term outcomes following a large vessel occlusion (LVO) stroke is the degree of collateral arterial circulation. We aimed to develop and evaluate machine-learning models that quantify LVO collateral status using admission computed tomography angiography (CTA) radiomics. METHODS: We extracted 1116 radiomic features from the anterior circulation territories from admission CTAs of 600 patients experiencing an acute LVO stroke. We trained and validated multiple machine-learning models for the prediction of collateral status based on consensus from two neuroradiologists as ground truth. Models were first trained to predict (1) good vs. intermediate or poor, or (2) good vs. intermediate or poor collateral status. Then, model predictions were combined to determine a three-tier collateral score (good, intermediate, or poor). We used the receiver operating characteristics area under the curve (AUC) to evaluate prediction accuracy. RESULTS: We included 499 patients in training and 101 in an independent test cohort. The best-performing models achieved an averaged cross-validation AUC of 0.80 ± 0.05 for poor vs. intermediate/good collateral and 0.69 ± 0.05 for good vs. intermediate/poor, and AUC = 0.77 (0.67-0.87) and AUC = 0.78 (0.70-0.90) in the independent test cohort, respectively. The collateral scores predicted by the radiomics model were correlated with (rho = 0.45, p = 0.002) and were independent predictors of 3-month clinical outcome (p = 0.018) in the independent test cohort. CONCLUSIONS: Automated tools for the assessment of collateral status from admission CTA-such as the radiomics models described here-can generate clinically relevant and reproducible collateral scores to facilitate a timely treatment triage in patients experiencing an acute LVO stroke.

OAB supraspinal control network, transition with age, and effect of treatment: A systematic review.

OBJECTIVE: In light of a better understanding of supraspinal control of nonneurogenic overactive bladder (OAB), the prevalence of which increases with age, functional imaging has gained significant momentum. The objective of this study was to perform a systematic review on the transition of supraspinal control of OAB with age, the effect of therapeutic modalities, and a coordinate-based meta-analysis of all neuroimaging evidence on supraspinal OAB control in response to bladder filling. METHODOLOGY: We performed a systematic literature search of all relevant libraries in November 2021. The coordinates of brain activity were extracted from eligible neuroimaging studies to perform an activation likelihood estimation (ALE) meta-analysis. RESULTS: A total of 16 studies out of 241 were selected for our systematic review. Coordinates were extracted from five experiments involving 70 patients. ALE meta-analysis showed activation of the insula, supplementary motor area, dorsolateral prefrontal cortex, anterior cingulate gyrus, and temporal gyrus with a transition of activation patterns with age, using a threshold of uncorrected p < 0.001. Among young patients, neuroplasticity allows the activation of accessory circuits to maintain continence, as in the cerebellum and temporoparietal lobes. Anticholinergics, pelvic floor muscle training, sacral neuromodulation, and hypnotherapy are correlated with supraspinal changes attributed to adaptability and possibly a substratum of an intrinsic supraspinal component. The latter is better demonstrated by a resting-state functional connectivity analysis, a promising tool to phenotype OAB with recent successful models of predicting severity and response to behavioral treatments. CONCLUSION: Future neuroimaging studies are necessary to better define an OAB neurosignature to allocate patients to successful treatments.

Similar admission NIHSS may represent larger tissue-at-risk in patients with right-sided versus left-sided large vessel occlusion.

BACKGROUND: We investigated the effects of the side of large vessel occlusion (LVO) on post-thrombectomy infarct volume and clinical outcome with regard to admission National Institutes of Health Stroke Scale (NIHSS) score. METHODS: We retrospectively identified patients with anterior LVO who received endovascular thrombectomy and follow-up MRI. Applying voxel-wise general linear models and multivariate analysis, we assessed the effects of occlusion side, admission NIHSS, and post-thrombectomy reperfusion (modified Thrombolysis in Cerebral Infarction, mTICI) on final infarct distribution and volume as well as discharge modified Rankin Scale (mRS) score. RESULTS: We included 469 patients, 254 with left-sided and 215 with right-sided LVO. Admission NIHSS was higher in those with left-sided LVO (median (IQR) 16 (10-22)) than in those with right-sided LVO (14 (8-16), p>0.001). In voxel-wise analysis, worse post-thrombectomy reperfusion, lower admission NIHSS score, and poor discharge outcome were associated with right-hemispheric infarct lesions. In multivariate analysis, right-sided LVO was an independent predictor of larger final infarct volume (p=0.003). There was a significant three-way interaction between admission stroke severity (based on NIHSS), LVO side, and mTICI with regard to final infarct volume (p=0.041). Specifically, in patients with moderate stroke (NIHSS 6-15), incomplete reperfusion (mTICI 0-2b) was associated with larger final infarct volume (p<0.001) and worse discharge outcome (p=0.02) in right-sided compared with left-sided LVO. CONCLUSIONS: When adjusted for admission NIHSS, worse post-thrombectomy reperfusion is associated with larger infarct volume and worse discharge outcome in right-sided versus left-sided LVO. This may represent larger tissue-at-risk in patients with right-sided LVO when applying admission NIHSS as a clinical biomarker for penumbra.

Imaging of endoscopic cystogastrostomy in pancreatic walled-off necrosis: what the radiologist needs to know.

Acute pancreatitis is a frequent entity encountered by radiologists. In 2012, the Atlanta criteria were revised to help radiologists use a common nomenclature when describing acute pancreatitis and its complications. One delayed complication of acute necrotizing pancreatitis in walled-off necrosis, a collection seen at least 4 weeks after an episode of acute pancreatic necrosis and/or acute peripancreatic necrosis. Multiple treatments have been adapted in the setting of walled-off necrosis, including endoscopic cystogastrostomy. The focus of this article is to familiarize the radiologist with the imaging appearance of this procedure as well as, review the outcomes and potential complications of endoscopic cystogastrostomy.

Inferior vena cava thrombus secondary to blunt abdominal trauma.

A 15-year-old female presented to the emergency department of a level 1 trauma centreafter being involved in a high-speed motor vehicle accident. The patient underwent a contrast-enhanced CT scan of the abdomen and pelvis obtained with a 60-70 s delay as part of the institution's polytrauma protocol. The CT scan demonstrated multiple hepatic lacerations and a filling defect in the suprahepatic inferior vena cava adjacent to the cavoatrial junction. Inferior vena cava thrombus secondary to blunt abdominal trauma is extremely rare, and to our knowledge, this is the first reported case of acute thrombus diagnosed by CT at the time of initial injury. There is limited literature on management of this entity. Possible treatments range from conservative approaches to anticoagulation and placement of IVC filters.