Histogram analysis of apparent diffusion coefficient for preoperative prediction of mid-term efficacy of high-intensity focused ultrasound in the treatment of uterine fibroids.

PURPOSE: This study was designed to investigate the preoperative prediction of the mid-term efficacy of high-intensity focused ultrasound (HIFU) in the treatment of uterine fibroids by apparent diffusion coefficient (ADC) histogram analysis.

METHODS

Eighty-six patients with a total of 101 uterine fibroids were retrospectively collected consecutively. The region of interest (ROI) was outlined layer by layer on diffusion-weighted imaging (DWI) images with b = 1000 s/mm2 to obtain ADC histogram parameters, including the mean, maximum, minimum, 10th, 25th, 50th, 75th and 90th percentiles as well as skewness, kurtosis, and entropy. The volume reduction rate (VRR) of fibroids at 6 months postoperatively was calculated as an indicator of the mid-term effect, and according to the VRR, the cohort was divided into a markedly effective group (VRR ≥ 50%) and a nonmarkedly effective group (VRR < 50%). Differences in ADC histogram parameters between the markedly effective and nonmarkedly effective groups were analyzed by applying univariate and multivariate binary logistic regression to screen out statistically significant indicators, and the predictive efficacy of the relevant ADC histogram parameters was assessed by receiver operating characteristic (ROC) curves.

RESULTS

The markedly effective group included 42 fibroids, and the noneffective group included 59 fibroids. The results of the univariate analysis showed that ADCmean, ADCmax, ADC10th, ADC25th, skewness, kurtosis, and entropy were significantly different between the two groups. The results of the multivariate analysis showed that ADC10th and skewness were statistically significant indicators, the area under the ROC curve (AUC) was 0.678 and 0.739, respectively, and the combined AUC of the two was 0.790. Major study limitations include: this is a single-center retrospective study, the investigator manually segmented the lesions, and no further analysis of postoperative pathology regarding the findings of the study.

CONCLUSION

ADC histogram analysis helps to preoperatively predict the mid-term efficacy of HIFU in the treatment of uterine fibroids. ADC10th and skewness are independent predictors of the mid-term efficacy of HIFU, and the combined efficacy of the two is superior to that of a single indicator.