Diagnostic of intravoxel incoherent motion diffusion-weighted imaging histogram parameters in distinguis-hing between benign and malignant thyroid nodules
Objective:The purpose of this study was to investigate the diagnostic efficacy of his-togram parameters extracted from intravoxel incoherent motion(IVIM)DWI in distinguishing be-tween benign and malignant thyroid nodules.Methods:The clinical data of 51 patients with thyroid nodule disease confirmed by surgery and pathology from March 2017 to September 2022 were retro-spectively included,including 24 cases of benign nodules and 27 cases of malignant nodules,all con-firmed by surgical pathology.Preoperative multi-b-value small field-of-view diffusion-weighted imaging was performed to generate maps of the true diffusion coefficient(D),the pseudo-diffusion coefficient(D*),and the perfusion fraction(f),as well as the apparent diffusion coefficient(ADC)map with b value of 990s/mm2.The entire lesion volume of the region of interest(VOI)was manually delineated.Using a custom-made MATLAB program,the 5-,15-,85-,and 95-percentile(named as P5,P15,P85 and P95),mean,interquartile range,skewness,root-mean-square deviation,and coefficient of variation were calculated for the D-,D*-,and f-maps within the VOI,as well as the mean ADC value within the VOI.The intergroup differences of IVIM histogram parameters,average ADC values and basic clinical information were compared using t-test or Mann-Whitney U-test,and then the statistically significant variables with P＜0.05 were selected out for establishing a combined model using logistic regression method.The diagnostic efficacy of the combined model in distinguishing between benign and malignant thyroid nodules was then evaluated using receiver operating characteristic(ROC)curve analysis.Re-sults:There were significant intergroup differences in gender,the values of mean ADC,P5,P15,P85 and P95,skewness,and root-mean-square deviation of the nodules on the D-map,and P5,P15,mean,skewness,and coefficient of variation on the D*-map(all P＜0.05).Three optimal histogram parame-ters were finally selected(P＜0.005),including skewness,P15 value and root-mean-square deviation on the D-map.The AUC of the combined radiomics model constructed by mean ADC value,gender combined with skewness,P15 value,and root-mean-square deviation on the D-map was 0.94(95％CI:0.84～0.99),with a sensitivity of 88.46％and a specificity of 90.91％.The AUC of the conventional combined model constructed by mean ADC value and gender was 0.86(95％CI:0.74～0.94),with a sensitivity of 77.78％and a specificity of 87.50％.Conclusion:Compared with the prediction model con-structed by average ADC value and gender,the combined model constructed with IVIM-DWI histo-gram parameters,ADC value and gender can improve the diagnostic efficacy for benign and malignant thyroid nodules.
Thyroid nodulesIntravoxel incoherent motionDiffusion-weighted imagingHis-togramDiagnostic model
万方数据
维普
