Diffusion-weighted magnetic resonance imaging to differentiate malignant from benign gallbladder disorders

Area of Science:

• Medical Imaging
• Radiology
• Oncology

Background:

• Gallbladder disorders present a diagnostic challenge, with differentiation between malignant and benign conditions crucial for patient management.
• Conventional magnetic resonance (MR) imaging morphology has limitations in accurately distinguishing gallbladder malignancies.

Purpose of the Study:

• To evaluate the diagnostic utility of apparent diffusion coefficient (ADC) and lesion to spinal cord ratio (LSR) derived from diffusion-weighted MR imaging (DWI).
• To compare the performance of ADC and LSR with morphological assessment alone in differentiating malignant from benign gallbladder disorders.

Main Methods:

• A retrospective review of 91 patients (13 with malignancy, 78 benign) with gallbladder disorders.
• Calculation of ADC values from DWI and measurement of LSR by comparing gallbladder wall signal intensity to spinal cord signal intensity.
• Assessment of morphological features including massive formation, disrupted mucosal line, and absence of a two-layered pattern.

Main Results:

• ADC and LSR showed areas under the curve of 0.861 and 0.906, respectively, in receiver operating characteristic analysis.
• Morphological assessment alone achieved 76.9% sensitivity, 84.0% specificity, and 83.0% accuracy.
• Combining morphological findings with ADC (< 1.2 × 10(-3)mm(2)/s) or LSR (> 0.48) significantly improved diagnostic performance to 73.0% sensitivity, 96.2% specificity, and 92.9% accuracy.

Conclusions:

• Apparent diffusion coefficient (ADC) and lesion to spinal cord ratio (LSR) in diffusion-weighted MR imaging enhance the diagnostic accuracy for gallbladder disorders.
• The integration of DWI-derived metrics with conventional MR morphology offers superior performance in differentiating malignant from benign gallbladder conditions.