Mayumi Takamune Debora, Miranda João, Mariussi Miriana, Reif de Paula Thais, Mazaheri Yousef, Younus Eyesha, Jethwa Krishan R, Knudsen Cody C, Bizinoto Valesca, Cardoso Daniel, de Arimateia Batista Araujo-Filho José, Sparapan Marques Carlos Frederico, Higa Nomura Cesar, Horvat Natally
Hospital Sírio-Libanês, São Paulo, Brazil.
Mayo Clinic, Rochester, USA.
Abdom Radiol (NY). 2025 Jul 11. doi: 10.1007/s00261-025-05102-8.
Diffusion-weighted imaging (DWI) has become a cornerstone of high-resolution rectal MRI, providing critical functional information that complements T2-weighted imaging (T2WI) throughout the management of rectal cancer. From baseline staging to restaging after neoadjuvant therapy and longitudinal surveillance during nonoperative management or post-surgical follow-up, DWI improves tumor detection, characterizes treatment response, and facilitates early identification of tumor regrowth or recurrence. This review offers a comprehensive overview of DWI in rectal cancer, emphasizing its technical characteristics, optimal acquisition strategies, and integration with qualitative and quantitative interpretive frameworks. The manuscript also addresses interpretive pitfalls, highlights emerging techniques such as intravoxel incoherent motion (IVIM), diffusion kurtosis imaging (DKI), and small field-of-view DWI, and explores the growing role of radiomics and artificial intelligence in advancing precision imaging. DWI, when rigorously implemented and interpreted, enhances the accuracy, reproducibility, and clinical utility of rectal MRI.
扩散加权成像（DWI）已成为高分辨率直肠MRI的基石，在直肠癌的整个管理过程中提供关键的功能信息，补充了T2加权成像（T2WI）。从基线分期到新辅助治疗后的再分期，以及在非手术治疗或术后随访期间的纵向监测，DWI可改善肿瘤检测、表征治疗反应，并有助于早期识别肿瘤再生长或复发。本综述全面概述了DWI在直肠癌中的应用，强调其技术特征、最佳采集策略以及与定性和定量解释框架的整合。本文还讨论了解释陷阱，重点介绍了诸如体素内不相干运动（IVIM）、扩散峰度成像（DKI）和小视野DWI等新兴技术，并探讨了放射组学和人工智能在推进精准成像方面日益增长的作用。当严格实施和解释时，DWI可提高直肠MRI的准确性、可重复性和临床实用性。
