Magnetic Resonance and Diffusion-Weighted Imaging Characteristics of Abdominal Wall Endometriosis: A Cross-Sectional Study

Aim: To characterize MRI and diffusion-weighted imaging (DWI) of histologically confirmed abdominal wall endometriosis (AWE) lesions and investigate the potential role of apparent diffusion coefficient (ADC) measurements in preoperative diagnosis.Materials and Methods: This retrospective cross-sectional study included twenty-four women aged 24–44 years with histologically confirmed AWE. MRI protocols included T1-weighted, T2-weighted, fat-suppressed contrast-enhanced sequences, and DWI (b-values: 50, 400, 800 sec/mm2). ADC values were measured for AWE lesions and the normal rectus abdominis muscle. MRI signal characteristics, enhancement patterns, and quantitative ADC values were analyzed.Results: The endometrial lesions on the abdominal wall appeared predominantly heterogeneous or slightly hyperintense on the T2-weighted images and were isointense or slightly hyperintense on the T1-weighted images. Patchy T1-hyperintense hemorrhagic foci were observed in 70.8% of cases. Quantitative analysis of diffusion-weighted imaging showed that the mean ADC value of the AWE lesions (1.19 ±0.26 × 10-³ mm²/sec) was significantly lower than that of the normal rectus abdominis muscle (1.32 ± 0.20 × 10-³ mm²/sec). The difference between the two groups reached statistical significance (p = 0.042).Conclusion: MRI in combination with DWI provides valuable morphologic and microstructural information for the evaluation of AWE. ADC measurements can serve as supportive parameters in preoperative assessment, although further comparative studies with other abdominal wall masses are warranted.