Purpose:
To evaluate the diagnostic accuracy of different abbreviated magnetic resonance imaging (AMRI) protocols consisting of dynamic enhanced + T2-weighted imaging (T2W) and diffusion-weighted imaging (DWI) + T2W for the detection and charac­terization of liver metastases in a patient group with known colorectal cancer.

Material and methods:
A total of 197 hepatic lesions were retrospectively analyzed across 3 different MRI sets: AMRI-1 (dynamic enhanced + T2W), AMRI-2 (DWI + T2W), and a standard MRI protocol. The patient cohort included 100 individuals (63 males, 37 females) with a mean age of 62.6 years (SD: 11.1 years). Lesions were characterized as benign, malignant, or indeterminate based on histopathology, positron emission tomography-computed tomography (PET-CT), and follow-up imaging.

Results:
The standard MRI protocol identified 197 liver lesions (175 metastatic, 18 benign, and 4 indeterminate); 142 lesions (72.1%) were larger than 10 mm, with the majority being metastatic (140/142). Radiologist 1 identified 195 lesions using the AMRI-1 protocol (175 metastatic, 15 benign, and 5 indeterminate). The sensitivity per lesion was 89.7% (95% CI: 0.85-0.93). Radiologist 2 identified 183 lesions using the AMRI-2 protocol (169 metastatic, 6 benign, and 8 indeterminate). The sensitivity per lesion was 92.3% (95% CI: 0.88-0.95). No statistically significant difference was found in sensitivity between the AMRI-1 and AMRI-2 and standard MRI protocols (p > 0.05).

Conclusions:
The standard MRI protocol demonstrated the highest sensitivity and specificity for detecting and charac­terizing liver metastases. However, differences between the protocols were not statistically significant. Abbreviated MRI protocols, particularly the AMRI-2 protocol incorporating diffusion-weighted imaging, could serve as an effec­tive alternative for routine clinical practice.