Abstract
To systematically evaluate the utility of different magnetic resonance imaging (MRI) features, including quantitative diffusion-weighted imaging, in differentiating benign from malignant pediatric orbital masses. The use of MRI in 40 pediatric patients with orbital masses was retrospectively reviewed. Multiple subjective and objective MRI parameters, including lesion mean apparent diffusion coefficient (ADC) values and lesion-to-thalamus ADC ratio were recorded. Bivariate analysis was done to identify parameters that were significantly different between benign and malignant subgroups. Receiver operating curves were used to establish optimal cut-off values for lesion mean ADC and lesion-to-thalamus ADC ratio for predicting benign versus malignant lesions. Lesion mean ADC, lesion-to-thalamus ADC ratio and extent of contrast enhancement showed statistically significant differences between the two subgroups. For distinguishing benign from malignant lesions, a lesion mean ADC cut-off value of 1.14 × 10-3 mm2/s provided a sensitivity of 84% and specificity of 100%, while an ADC ratio of 1.4 provided a sensitivity of 81% and specificity of 89%. Quantitative diffusion-weighted imaging can be a useful adjunct in characterizing pediatric orbital masses by MRI, and thus help in clinical decision making.
