Perfusion response to treatment outcome: CEUS links oxytocin to HIFU efficacy prediction for uterine fibroids.
Oxytocin can induce significant perfusion changes in uterine fibroids, which may help predict the efficacy of HIFU treatment.
Where it sits
this study against the rest of the oxytocin corpusSummary and findings
This study evaluated oxytocin-induced perfusion changes in uterine fibroids in 55 patients using contrast-enhanced ultrasound (CEUS) and assessed their predictive value for high-intensity focused ultrasound (HIFU) ablation efficacy. Patients received an intravenous oxytocin infusion at a dose of 0.10 U/ml over 10 minutes. The findings indicated significant differences in perfusion parameters between groups based on ablation efficacy.
Abstract
Objectives To evaluate oxytocin-induced perfusion changes in uterine fibroids using contrast-enhanced ultrasound(CEUS) and determine their predictive value for high-intensity focused ultrasound (HIFU) ablation efficacy. Methods Fifty-five patients (mean age 42.15 ± 5.34 years). with 78 uterine fibroids underwent oxytocin-enhanced HIFU therapy. CEUS was performed before and after intravenous oxytocin infusion (0.10 U/ml over 10 min). Perfusion changes were assessed using two parameters:(1) Arterial-phase Perfusion Delay Time difference (APDTΔt), defined as the time difference in enhancement onset of fibroids before and after oxytocin exposure; (2) Visual Perfusion Grading (VPG), based on relative contrast perfuse reduction of fibroids at the end of the arterial phase(Grade1:≤30%;Grade2:30-70%;Grade3:≥70%). Post-treatment contrast-enhanced pelvic MRI was used to calculate fibroid volume and non-perfused volume(NPV),from which ablation ratio was derived. Fibroids were dichotomized by ablation efficacy (≥70%vs < 70%), and correlation analyses and ROC curves were used to evaluate predictive performance. Results Fibroids in the <70% ablation group showed a mean APDT(Δt) of 8.32 ± 5.61s and 52.2%(12/23) VPG as Grade1. In the ≥70% group, APDT(Δt) was significantly longer (16.76 ± 12.12 s), and 54.5%(30/55) VPG were Grade3. Both APDT(Δt) and VPG differed significantly between groups (p < 0.05), Showing strong correlations with ablation ratio (r = 0.577 and r = 0.585; both p < 0.001). Thresholds of APDT(Δt) >3.5 s and VPG >1.5 yielded sensitivities of 83.6% and 87.3%, specificity of 65.2% and 52.3%, with AUCs of 0.791 and 0.725, respectively. Conclusion CEUS can effectively detect oxytocin-mediated perfusion changes in uterine fibroids. These changes are strongly associated with HIFU ablation outcomes, and in particular, Arterial-phase Perfusion Delay Time demonstrates robust predictive value for treatment efficacy.
Background
This paper addresses the relationship between oxytocin-induced perfusion changes in uterine fibroids and the efficacy of high-intensity focused ultrasound (HIFU) ablation. Prior research has indicated that perfusion changes may correlate with treatment outcomes, but specific predictive parameters have not been well established. Understanding these relationships is crucial for improving treatment strategies for uterine fibroids.
Methods
This study involved 55 patients with a mean age of 42.15 ± 5.34 years, all of whom had 78 uterine fibroids. Patients received an intravenous infusion of oxytocin at a dose of 0.10 U/ml over 10 minutes before undergoing HIFU therapy. The primary outcomes measured were Arterial-phase Perfusion Delay Time difference (APDTΔt) and Visual Perfusion Grading (VPG), assessed before and after oxytocin infusion.
Results
The primary endpoint showed that the mean APDT(Δt) was 8.32 ± 5.61s in the <70% ablation group, while it was significantly longer at 16.76 ± 12.12 s in the ≥70% group (p<0.05). The VPG results indicated that 52.2% of the <70% group were graded as Grade1, while 54.5% of the ≥70% group were graded as Grade3. Correlation analyses revealed strong correlations with ablation ratio (r=0.577 and r=0.585, both p<0.001).
Interpretation
The findings suggest that oxytocin-induced perfusion changes can predict HIFU ablation efficacy, with APDT(Δt) showing a robust predictive value. However, while the statistical significance is clear, the clinical relevance of these findings may be limited by the small sample size and reliance on surrogate endpoints. Further studies are needed to validate these results in larger populations and assess long-term outcomes.
Key findings
- Fibroids in the <70% ablation group showed a mean APDT(Δt) of 8.32 ± 5.61s.
- In the ≥70% group, APDT(Δt) was significantly longer at 16.76 ± 12.12 s.
- 52.2% (12/23) of the <70% group had VPG as Grade1.
- 54.5% (30/55) of the ≥70% group had VPG as Grade3.
- Thresholds of APDT(Δt) >3.5 s yielded a sensitivity of 83.6% and specificity of 65.2%.
- Thresholds of VPG >1.5 yielded a sensitivity of 87.3% and specificity of 52.3%.
Limitations
- small sample size of 55 patients
- reliance on surrogate endpoints for efficacy prediction
- no long-term follow-up reported
- single-site study may limit generalizability