Application of cellular microstructural diffusion MRI (cell size imaging) in rectal lesions: a preliminary study.

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Rectal lesions require accurate preoperative evaluation for effective treatment planning.
• Histological typing and prognostic factor assessment are crucial for rectal cancer management.

Purpose of the Study:

• To assess the value of cellular microstructural mapping via IMPULSED MRI in evaluating rectal lesions.
• To differentiate histological types and prognostic factors of rectal lesions using advanced MRI techniques.

Main Methods:

• Sixty-six patients with rectal lesions underwent MRI, including conventional DWI and IMPULSED sequences (OGSE, PGSE).
• Key parameters measured: mean cell diameter (dmean), intracellular fraction (vin), extracellular diffusivity (dex), cellularity, and apparent diffusion coefficient (ADC).
• Receiver operating characteristic (ROC) curve analysis was used to determine diagnostic power.

Main Results:

• Malignant lesions exhibited higher vin and cellularity, and lower dex and ADC values compared to benign lesions.
• Rectal common adenocarcinoma (AC) showed significantly higher vin and cellularity, and lower dex and ADC values than mucinous adenocarcinoma (MC).
• The IMPULSED method demonstrated high diagnostic power (AUCs ranging from 0.726 to 0.991) for differentiating lesion types and predicting tumor budding.

Conclusions:

• Cellular microstructural mapping by IMPULSED MRI is a valuable tool for preoperative rectal lesion evaluation.
• This technique aids in differentiating malignant from benign lesions, distinguishing AC from MC, and predicting tumor budding status.
• IMPULSED MRI offers significant potential for enhancing diagnostic accuracy in rectal lesion assessment.