Evaluation of physician experience in achieving non-perfused volume ratio of high-intensity focused ultrasound ablation for uterine fibroids: a multicentre study

Abstract

Objective To evaluate the effect of different levels of physician experience on the high-intensity focused ultrasound (HIFU) ablation of uterine fibroids and to provide a reference for the use of non-perfused volume ratio (NPVR) standards during training. Methods This prospective multicentre study enrolled patients with uterine fibroids. The effect of the physician’s level of experience on the outcomes under different NPVR standards and the learning curve of six centres without HIFU experience were analysed. The impact of patient demographic and clinical characteristics were also evaluated. Results A total of 1352 patients from 20 centres were included in the study. The median NPVRs were 92.00%, 88.10% and 92.86% in the no experience group, inexperienced group and experienced group, respectively. Posterior wall fibroids, lateral wall fibroids and fundus fibroids were inversely correlated with NPVR, while experienced physicians were positively correlated with NPVR. With NPVR ≥ 70% and NPVR ≥ 80% standards, physicians in the no experience group completed the learning curve on the 11th and 16th procedure, respectively. Physicians under a standard of an NPVR ≥ 90% did not complete the learning curve. Conclusions NPVR ≥ 80% is a standard that is worth using for HIFU treatment of uterine fibroids.

Prediction of non-perfusion volume ratio for uterine fibroids treated with ultrasound-guided high-intensity focused ultrasound based on MRI radiomics combined with clinical parameters

“…Third, we did not try to use other NPVR values as prediction dividing lines for treatment success, only NPVR ≥ 80% was used in this study. Because measures to achieve 80% NPVR is technically feasible and have been proven to be highly associated with a clinical treatment success [ 3 , 4 , 38 ]. Finally, while patients at both institutions were treated with the same HIFU system, a potential biased limitation is that the treatment was performed by different doctors, which could influenced dosage delivery or the termination of treatment.…”

“…As an ablation technique, the efficacy of HIFU is closely related to the immediate postoperative non-perfused volume ratio (NPVR). A higher NPVR heralds a significant improvement in the patient’s symptoms, and an NPVR of over 80% is considered as an indicator of therapeutic success in recent studies [ 3 , 4 ]. However, not all patients can benefit from this treatment because of several limitations, such as high cellularity and high vascularity in the fibroids, which will hinder the deposition of ultrasonic energy and make ablation outcomes unsatisfactory.…”

Development and validation of a radiomics model based on T2-weighted imaging for predicting the efficacy of high intensity focused ultrasound ablation in uterine fibroids

“…The NPV ratio (NPVR), defined as the NPV divided by the fibroid volume, was then calculated. We defined the higher ablation rate group was NPVR ≥80% [higher NPVR (h_NPVR)], and the lower ablation group was NPVR <80% [lower NPVR (l_NPVR)] ( Figure 2 ) ( 21 , 22 ).…”