# Hyperthermia Treatment Monitoring via Deep Learning Enhanced Microwave Imaging: A Numerical Assessment

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## Abstract

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## Simple Summary

## Abstract

## 1. Introduction

## 2. Material and Methods

#### 2.1. Electromagnetic Properties of Tissue

#### 2.2. The Microwave Imaging Problem

#### 2.3. Deep Learning Microwave Imaging Framework for HT Temperature Monitoring

#### 2.3.1. Microwave Imaging Processing

#### 2.3.2. Deep Learning Architecture for Classification

#### 2.4. Assessment of the DL-MWI Framework for Temperature Monitoring in Neck Tumor Hyperthermia

#### 2.4.1. Anatomical Model

#### 2.4.2. MWI Simulations

#### 2.4.3. MWI Imaging Results

#### 2.4.4. CNN Implementation: Categorical Labels

#### 2.4.5. CNN Implementation: Training

#### 2.4.6. Performance Assessment Metrics

## 3. Results

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Typical MWI setup configuration. A number of transmitting ${T}_{x}^{\left[v\right]}$ and receiving ${R}_{x}^{\left[m\right]}$ antennas surround the imaging domain $\mathsf{\Omega}$.

**Figure 2.**The basic ingredients of the proposed DL-MWI framework for temperature monitoring during HT treatments.

**Figure 4.**DL-MWI framework for monitoring temperature in neck tumor HT. Two separate CNNs simultaneously check the temperature status of the treated tumor and the spinal cord. In the figure, ${\mathsf{\Omega}}_{1}$ denotes the tumor region and ${\mathsf{\Omega}}_{2}$ is the spinal cord to be preserved.

**Figure 5.**The phantom adopted for the numerical study. Tissue segmentation (

**left**) and electromagnetic properties (

**right**).

**Figure 7.**Categorical cross-entropy optimization of the considered CNNs versus the number of epochs.

Class | DSC | MCC |
---|---|---|

Unheated | 0.953 | 0.928 |

Therapeutic | 0.932 | 0.887 |

Hot | 0.912 | 0.878 |

Class | DSC | MCC |
---|---|---|

Unheated | 0.920 | 0.855 |

Hot | 0.907 | 0.855 |

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**MDPI and ACS Style**

Yago Ruiz, Á.; Cavagnaro, M.; Crocco, L.
Hyperthermia Treatment Monitoring via Deep Learning Enhanced Microwave Imaging: A Numerical Assessment. *Cancers* **2023**, *15*, 1717.
https://doi.org/10.3390/cancers15061717

**AMA Style**

Yago Ruiz Á, Cavagnaro M, Crocco L.
Hyperthermia Treatment Monitoring via Deep Learning Enhanced Microwave Imaging: A Numerical Assessment. *Cancers*. 2023; 15(6):1717.
https://doi.org/10.3390/cancers15061717

**Chicago/Turabian Style**

Yago Ruiz, Álvaro, Marta Cavagnaro, and Lorenzo Crocco.
2023. "Hyperthermia Treatment Monitoring via Deep Learning Enhanced Microwave Imaging: A Numerical Assessment" *Cancers* 15, no. 6: 1717.
https://doi.org/10.3390/cancers15061717