# Development and validation of a multi-parametric energy density optimization algorithm for microwave ablation of benign thyroid nodules: a retrospective cohort study

## TL;DR

This study developed a personalized algorithm to optimize energy density during microwave ablation for better treatment of benign thyroid nodules.

## Contribution

A three-step energy density algorithm was created using patient-specific factors to improve microwave ablation outcomes.

## Key findings

- 37.8% of patients achieved treatment success with a volume reduction rate (VRR) >90% at 12 months.
- The energy density prediction model showed excellent discrimination with an AUC of 0.902.
- Independent predictors of treatment success included maximum diameter, baseline volume, WBC count, CRP, and enhancement pattern.

## Abstract

This study aimed to develop and validate a personalized energy density optimization algorithm for microwave ablation of benign thyroid nodules.

This retrospective cohort study analyzed 82 patients undergoing MWA for benign thyroid nodules. Patients were divided into treatment success group (VRR >90%, n=31) and treatment insufficient group (VRR ≤90%, n=51) based on 12-month outcomes. LOESS curve fitting analysis was applied to explore the relationship between energy density and VRR at 12 months. Linear regression was used to predict optimal energy density, and logistic regression was used to estimate treatment success probability. Performance was evaluated using receiver operating characteristic (ROC) analysis (AUC), calibration assessment, and decision curve analysis. A three-step personalized energy density algorithm was established based on the regression analyses.

At post-ablation 12-months, 37.8%(n=31) achieving treatment success. LOESS curve fitting revealed a plateau effect above 4.0 J/mm3. The energy density prediction model incorporated vertical diameter, baseline volume, TSH, neutrophil count, and peak intensity (adjusted R2 = 0.47). Prediction model demonstrated excellent discrimination (AUC=0.902) with optimal cutoff probability at 0.417. Independent predictors included maximum diameter, baseline volume, WBC count, CRP, and enhancement pattern. Decision curve showed the benefit threshold was 0.8. The three-step algorithm was developed, which including baseline energy calculation, success probability estimation, and adaptive adjustment when predicted success <80%.

Personalized energy density calculation based on patient-specific factors has the potential to significantly improve MWA outcomes for benign thyroid nodules. This algorithmic approach enables precision treatment planning and optimal patient selection.