To do Elastography or not to do? Comparative study between shear wave Elastography versus Doppler in the Evaluation of O-RADS 3 and 4 Ovarian Lesions

Purpose Ovarian lesions are common diseases nowadays that should be diagnosed accurately. The Ovarian-Adnexal Reporting and Data System (O-RADS) classification helps to a great extent in categorizing the type of ovarian lesions, whether benign, malignant, or even borderline, that fasten the decision of the treatment plan. The role of Doppler is vital to inform the perfusion of the tissue, thus can predict whether the tumor is benign or malignant. The elasticity of the tissues by shear wave elastography supports the evaluation of ovarian lesions and plays a role as a relatively recent method for diagnosis. This study was done to compare the diagnostic efficacy of Doppler and ultrasonography versus shear wave elastography (SWE) for O-RADS 3 and 4 ovarian lesions. Methods Forty-eight female patients were radiologically diagnosed with ovarian lesions, and all of them were included in the final statistical analysis. A pelvic-abdominal ultrasound was performed. Doppler and shear wave elastography techniques were applied for all patients then the findings were correlated to histopathology. Results As regards the color Doppler, there were 5 true positive results (10.4%), 32 true negative results (66.7%), 7 false positive results (14.6%), and 4 false negative results (8.3%). Its sensitivity of 55.5%, specificity of 82% and diagnostic accuracy 66%. Regarding the qualitative evaluation of SWE, there was 1 true positive result (2.1%), 32 true negative results (66.7%), 7 false positive results (14.6%), and 8 false negative results (16.7%). Its sensitivity was 11.1%, specificity of 82% and the diagnostic accuracy was 67.8%; however, regarding its quantitative evaluation by measuring the kPa value, the sensitivity of the technique raised to be 66.7% with a significant P value < 0.001. Conclusion Color Doppler is an effective diagnostic technique that shows a satisfactory level of agreement with pathology findings when it applies to distinguishing benign from malignant tumors, with (p-value = 0.019) fair agreement (k = 0.33). Regarding the SWE, the quantitative evaluation by measuring the KPA value, which could be used to distinguish between benign and malignant lesions at a cutoff level of > 31 with 66.7% sensitivity, 76.9% specificity, 40% PPV, and 90.9% NPV with a significant P value < 0.001, is much more precise than the qualitative evaluation by elastogram.