Diffusion kurtosis imaging in acute ischemic stroke: A systematic review of clinical correlations and prognostic utility

Purpose: Accurate early prediction of long-term disability in acute ischemic stroke remains challenging, necessitating sensitive imaging biomarkers. Diffusion Kurtosis Imaging (DKI) is an emerging modality with high sensitivity, potentially offering numerous diffusion-based prognostic markers for various stroke outcomes, which we aim to establish via this systematic review. Methods: Five databases were searched to obtain records of studies that were performed in hemispherical, first-ever acute ischemic stroke patients from the inception of the database until January 2025. Studies assessing the ability of DKI to predict various motor, functional, tissue, or neurological outcomes were included. The quality of each study was assessed via the Quality of Prognostic Studies (QUIPS) tool. Two independent reviewers performed two-step screening and data extraction, and the data were synthesized, qualitatively assessed, and reported. Results: Out of 215 records, 11 studies were included in the review, with 550 total samples diagnosed with acute ischemic stroke who were followed up for a period ranging from 2 to 365 days, with a mean age of 58 ± 6.3 years. Motor outcomes were assessed in 1 study, functional outcomes in 4 studies, tissue-related changes in 2 studies, and neuropsychiatric sequelae in 4 studies. All the studies were of moderate to high quality and thus had a low risk of bias. Among the DKI parameters, Mean Kurtosis was correlated with most outcome assessment tools. Conclusion: Stroke rehabilitation is a resource-intensive process necessitating optimal patient selection. DKI shows promise for predicting early microstructural changes and global functional outcomes, especially using the Mean Kurtosis (MK) parameter, though evidence for motor-specific recovery remains limited.