Specific Absorption Rate Optimization in Microwave Cancer Hyperthermia via Local Power Synthesis Algorithm.
Simple Summary: This study investigates the application of the Alternating Projections Algorithm (APA) for specific absorption rate (SAR)-based optimization in microwave hyperthermia treatment planning. This method leverages a two-level power mask to iteratively shape the electric field distribution...
| Publicado en: | Cancers Vol. 17; no. 17; pp. 2813 - 2832 |
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| Autores principales: | , , , , |
| Formato: | algorithm equations & formulas pictorial research tables/charts Journal Article |
| Publicado: |
MDPI
Sep2025
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=187985492&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 187985492 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 20726694 B74B jtl: Cancers issn: 20726694 maglogo: N pubinfo: dt: Sep2025 vid: 17 iid: 17 pid: 97109 pub: MDPI artinfo: ui: 187985492 187985492 187985492 10.3390/cancers17172813 187985492 ppf: 2813 ppct: 19 formats: tig: atl: Specific Absorption Rate Optimization in Microwave Cancer Hyperthermia via Local Power Synthesis Algorithm. aug: au: Firuzalizadeh, Maryam Gaffoglio, Rossella Giordanengo, Giorgio Righero, Marco Vecchi, Giuseppe affil: Department of Electronics and Telecommunications, Politecnico di Torino, 10129 Turin, Italy sug: subj: Algorithms Microwaves Therapeutic Use Hyperthermia, Induced Neoplasms Therapy Particle Swarm Optimization Absorption Head Anatomy and Histology Neck Anatomy and Histology Models, Anatomic Funding Source Human Temperature Phantoms, Imaging Electromagnetics Descriptive Statistics Heat Tissue Software Electric Impedance ab: Simple Summary: This study investigates the application of the Alternating Projections Algorithm (APA) for specific absorption rate (SAR)-based optimization in microwave hyperthermia treatment planning. This method leverages a two-level power mask to iteratively shape the electric field distribution, focusing energy deposition in the tumor region while limiting exposure in healthy tissues. To enhance the effectiveness of this approach, an adaptive mask threshold selection strategy is introduced, based on quantitative metrics that evaluate energy spillover. The performance of APA is assessed using two numerical models of the head and neck (H&N) region: a simplified cylindrical model and a realistic anatomical phantom. Comparative analysis are conducted against the widely used particle swarm optimization (PSO) technique. Results demonstrate that APA achieves comparable tumor coverage while offering superior hotspot suppression, positioning it as a promising deterministic alternative to meta-heuristic SAR optimization strategies. Objective: Microwave hyperthermia is a clinically validated adjunctive therapy in oncology, employing antenna applicators to selectively raise tumor tissue temperature to 40–44 °C. For deep-seated tumors, especially those in anatomically complex areas like the head and neck (H&N) region, phased array antennas are typically employed. Determining optimal antenna feeding coefficients is crucial to maximize the specific absorption rate (SAR) within the tumor and minimize hotspots in healthy tissues. Conventionally, this optimization relies on meta-heuristic global algorithms such as particle swarm optimization (PSO). Methods: In this study, we consider a deterministic alternative to PSO in microwave hyperthermia SAR-based optimization, which is based on the Alternating Projections Algorithm (APA). This method iteratively projects the electric field distribution onto a set of constraints to shape the power deposition within a predefined mask, enforcing SAR focusing within the tumor while actively suppressing deposition in healthy tissues. To address the challenge of selecting appropriate power levels, we introduce an adaptive power threshold search mechanism using a properly defined quality parameter, which quantifies the excess of deposited power in healthy tissues. Results: The proposed method is validated on both a simplified numerical testbed and a realistic anatomical phantom. Results demonstrate that the proposed method achieves heating quality comparable to PSO in terms of tumor targeting, while significantly improving hotspot suppression. Conclusions: The proposed APA framework offers a fast and effective deterministic alternative to meta-heuristic methods, enabling SAR-based optimization in microwave hyperthermia with improved tumor targeting and enhanced suppression of hotspots in healthy tissue. pubtype: Academic Journal doctype: algorithm equations & formulas pictorial research tables/charts Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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