Evaluation of malignant and benign renal lesions using diffusion-weighted MRI with multiple b values

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Limited data exists on diffusion-weighted (DW) magnetic resonance imaging (MRI) with multiple b values for renal lesion characterization.
• Accurate differentiation of benign and malignant renal lesions is crucial for patient management.

Purpose of the Study:

• To evaluate and compare the diagnostic performance of DW-MRI with multiple b values for characterizing renal lesions.
• To assess the utility of apparent diffusion coefficient (ADC) values and signal intensity curves in differentiating renal lesions.

Main Methods:

• Prospective inclusion of 63 renal lesions (36 malignant, 27 benign) in 60 patients.
• Acquisition of single-shot echo-planar DW abdominal MRI at 1.5T using seven b values and eight ADC maps.
• Analysis of signal intensities, lesion ADCs, lesion/normal parenchyma ADC ratios, and receiver-operating characteristic analysis.

Main Results:

• Malignant lesions showed significantly lower signal intensities and ADC values compared to benign lesions (P < 0.05 and P < 0.000, respectively, excluding b50 s/mm(2)).
• DW-MRI with multiple b values effectively distinguished between benign and malignant lesions, with an ADC threshold of 1.35 × 10(-3) mm(2)/s achieving 85.2% sensitivity and 65.6% specificity.
• The lesion/normal parenchyma ADC ratio proved more effective than lesion ADC alone.

Conclusions:

• Signal intensity curves derived from multi-b-value DW images, in conjunction with ADC values, can aid in differentiating malignant and benign renal lesions.
• Multi-b-value DW-MRI offers a promising non-invasive tool for renal lesion characterization.