APIS: A paired CT-MRI dataset for ischemic stroke segmentation challenge
Santiago Gómez, Daniel Mantilla, Gustavo Garzón, Edgar Rangel, Andrés Ortiz, Franklin Sierra-Jerez, Fabio Martínez
TL;DR
The paper introduces APIS, the first public paired NCCT–ADC dataset for ischemic stroke segmentation and a related ISBI 2023 challenge to evaluate CT-based lesion delineation with diffusion MRI guidance. It demonstrates radiologist agreement on ADC lesions and shows markedly better segmentation performance when ADC is available, compared with NCCT alone. The results underscore the value of cross-modality information and motivate future work on expanding paired data, robust registration, and synthetic modality generation to improve generalization. Overall, APIS provides a foundation for multimodal stroke segmentation research and benchmarking of image-to-image translation and integration approaches.
Abstract
Stroke is the second leading cause of mortality worldwide. Immediate attention and diagnosis play a crucial role regarding patient prognosis. The key to diagnosis consists in localizing and delineating brain lesions. Standard stroke examination protocols include the initial evaluation from a non-contrast CT scan to discriminate between hemorrhage and ischemia. However, non-contrast CTs may lack sensitivity in detecting subtle ischemic changes in the acute phase. As a result, complementary diffusion-weighted MRI studies are captured to provide valuable insights, allowing to recover and quantify stroke lesions. This work introduced APIS, the first paired public dataset with NCCT and ADC studies of acute ischemic stroke patients. APIS was presented as a challenge at the 20th IEEE International Symposium on Biomedical Imaging 2023, where researchers were invited to propose new computational strategies that leverage paired data and deal with lesion segmentation over CT sequences. Despite all the teams employing specialized deep learning tools, the results suggest that the ischemic stroke segmentation task from NCCT remains challenging. The annotated dataset remains accessible to the public upon registration, inviting the scientific community to deal with stroke characterization from NCCT but guided with paired DWI information.
