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Previous research estimated a prevalence of 3.4% Cerebral Visual Impairment (CVI)-related visual problems within primary school children, potentially compromising students’ performance. This study aimed to clarify how CVI-related visual difficulties relate to academic performance in standardized achievement tests. As part of the Luxembourg school monitoring programme, 1129 first graders (mean age of 7 years) participated in three competence tests (mathematics, early literacy and listening comprehension) and in student and parent questionnaires (background information). The same children took part in a CVI-related visual difficulties screening (Evaluation of Visuo-Attentional abilities battery, optometric and orthoptic measures). The sample was divided post-screening into 38 children with potential CVI-related visual difficulties (18 females, 20 males, mean age 7y, range 6–8y) and 890 typically developing (TD) children (445 females, 430 males, 15 missing, mean age 7y, range 5–10y). Compared to the TD sample children with CVI-related visual difficulties significantly underperformed in early literacy and mathematics, but not in listening comprehension, even when controlling for background characteristics known to influence performance (gender, socio-economic status, migration background, parental education, home language, age). The results confirm the association of CVI-related visual difficulties with learning processes already at primary school level and emphasize the need to implement a systematic screening for CVI-related visual difficulties, as early as possible within the school path, to ensure adequate measures are employed to aid students at risk. [ABSTRACT FROM AUTHOR]

Adequate perfusion is critical for maintaining normal brain function and aberrations thereof are hallmarks of many diseases. Pseudo‐Continuous Arterial Spin Labeling (pCASL) MRI enables noninvasive quantitative perfusion mapping without contrast agent injection and with a higher signal‐to‐noise ratio (SNR) than alternative methods. Despite its great potential, pCASL remains challenging, unstable, and relatively low‐resolution in rodents – especially in mice – thereby limiting the investigation of perfusion properties in many transgenic or other relevant rodent models of disease. Here, we address this gap by developing a novel experimental setup for high‐resolution pCASL imaging in mice and combining it with the enhanced SNR of cryogenic probes. We show that our new experimental setup allows for optimal positioning of the carotids within the cryogenic coil, rendering labeling reproducible. With the proposed methodology, we managed to increase the spatial resolution of pCASL perfusion images by a factor of 15 in mice; a factor of 6 in rats is gained compared to the state of the art just by virtue of the cryogenic coil. We also show that the improved pCASL perfusion imaging allows much better delineation of specific brain areas, both in healthy animals as well as in rat and mouse models of stroke. Our results bode well for future high‐definition pCASL perfusion imaging in rodents. [ABSTRACT FROM AUTHOR]

Purpose: Arterial spin labeling (ASL) is a widely used contrast‐free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM‐OSIPI ASL‐MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. Methods: Eight teams analyzed the challenge data, which included a high‐resolution T1‐weighted anatomical image and 10 pseudo‐continuous ASL datasets simulated using a digital reference object to generate ground‐truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra‐class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. Results: Absolute errors in CBF estimates compared to ground‐truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground‐truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. Conclusions: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top‐performing approaches as a step toward ASL standardization. [ABSTRACT FROM AUTHOR]