Optimization of laser dosimetry based on patient-specific anatomical models for the ablation of pancreatic ductal adenocarcinoma tumor DOI Creative Commons
Pouya Namakshenas, Francesco Maria Di Matteo, Leonardo Bianchi

et al.

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: July 8, 2023

Laser-induced thermotherapy has shown promising potential for the treatment of unresectable primary pancreatic ductal adenocarcinoma tumors. Nevertheless, heterogeneous tumor environment and complex thermal interaction phenomena that are established under hyperthermic conditions can lead to under/over estimation laser efficacy. Using numerical modeling, this paper presents an optimized setting Nd:YAG delivered by a bare optical fiber (300 µm in diameter) at 1064 nm working continuous mode within power range 2-10 W. For analysis, patient-specific 3D models were used, consisting tumors different portions pancreas. The time ablating completely producing toxic effects on possible residual cells beyond margins found be 5 W 550 s, 7 8 s tail, body, head tumors, respectively. Based results, during irradiation doses, injury was not evident either 15 mm lateral distances from or nearby healthy organs. present computational-based predictions also line with previous ex vivo studies, hence, they assist therapeutic outcome ablation neoplasms prior clinical trials.

Language: Английский

Estimation of porcine pancreas optical properties in the 600–1100 nm wavelength range for light-based therapies DOI Creative Commons
Pranav Lanka, Leonardo Bianchi, Andrea Farina

et al.

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Aug. 22, 2022

Abstract This work reports the optical properties of porcine pancreatic tissue in broad wavelength range 600–1100 nm. Absorption and reduced scattering coefficients ( µ a s ′) ex vivo pancreas were obtained by means Time-domain Diffuse Optical Spectroscopy. We have investigated different experimental conditions—including compression, repositioning, spatial sampling, temporal stability—the effect freezing procedure (fresh vs frozen-thawed pancreas), finally inter-sample variability. Good repeatability under conditions was (median coefficient variation less than 8% ~ 16% for ′, respectively). Freezing–thawing samples caused an irreversible threefold reduction ′ no on . The absorption spectra averaged over 0.12–0.74 cm −1 12–21 with 10% 40% respectively. calculated effective transport eff ) fresh shows that regions between 800–900 nm 1050–1100 are similar offer lowest attenuation considered (i.e., ranging from 2.4 to 2.7 ). These data, describing specific light-pancreas interactions therapeutic window first time, provide pivotal information planning light-based thermotherapies (e.g., laser ablation) instruction light models biophotonic applications involving this organ.

Language: Английский

Citations

15
Characterization of susceptibility artifacts in magnetic resonance thermometry images during laser interstitial thermal therapy: dimension analysis and temperature error estimation DOI Creative Commons
Martina De Landro, Céline Giraudeau, Juan M. Verde

et al.

Physics in Medicine and Biology, Journal Year: 2023, Volume and Issue: 68(8), P. 085022 - 085022

Published: Feb. 15, 2023

Objective.Laser interstitial thermal therapy (LITT) is a minimally invasive procedure used to treat lesion through light irradiation and consequent temperature increase. Magnetic resonance thermometry imaging (MRTI) provides multidimensional measurement of the inside target, thus enabling accurate monitoring damaged zone during procedure. In proton frequency shift-based thermometry, artifacts in images may strongly interfere with estimated maps. our work, after noticing formation dipolar-behavior artifact linkable magnetic susceptibility changes duringin vivoLITT, an investigation tissue-mimicking phantoms was implemented.Approach.The characterized: (i) by measuring area total volume error regions their evolution treatment; (ii) comparison reference provided three sensing needles. Lastly, strategy avoid devised using temperature-sensing needles implement temperature-controlled LITT.Main results.The appearance associated gas bubble unwanted treatment effects producing when 2 W laser power set. The analysis artifact's dimension demonstrated that sagittal plane dipolar-shape consistently spread following trend until reaching 8 times bigger than ablated one. Also, shape quite symmetric respect tip. An absolute showing negative Gaussian profile values up 64.4 °C estimated. Conversely, maximum 2.8 measured not-affected far from applicator Finally, regulating power, avoided, appreciable damage induced.Significance.These findings help improving MRTI-based guidance therapies.

Language: Английский

Citations

9
Model-Based Thermometry for Laser Ablation Procedure Using Kalman Filters and Sparse Temperature Measurements DOI Creative Commons

N. Schulmann,

M.A. Soltani-Sarvestani, Martina De Landro

et al.

IEEE Transactions on Biomedical Engineering, Journal Year: 2022, Volume and Issue: 69(9), P. 2839 - 2849

Published: March 1, 2022

Objective: We implement a data assimilation Bayesian framework for the reconstruction of spatiotemporal profile tissue temperature during laser irradiation. The predictions physical model simulating heat transfer in are associated with sparse measurements, using an Unscented Kalman Filter. xmlns:xlink="http://www.w3.org/1999/xlink">Methods: compare standard state-estimation filtering procedure joint-estimation (state and parameters) approach: whereas only is evaluated, filter corrects also uncertain parameters ( xmlns:xlink="http://www.w3.org/1999/xlink">i.e. , medium thermal diffusivity, beam properties). have tested method on synthetic data, measured agar-gel phantom porcine liver fiber optic sensors. xmlns:xlink="http://www.w3.org/1999/xlink">Results: allows retrieving accurate estimate distribution maximal error $< $ 1.5 notation="LaTeX">$^{\circ }$ C both 1D 2 2D data. Our approach suggesting strategy optimizing estimation based positions Under constraint two sensors, optimal obtained when one sensor placed proximity source, other non-symmetrical. xmlns:xlink="http://www.w3.org/1999/xlink">Conclusion: significantly improves predictive capability model. xmlns:xlink="http://www.w3.org/1999/xlink">Significance: This work opens new perspectives benefit frameworks therapy monitoring.

Language: Английский

Citations

13
Three-Phase-Lag Bio-Heat Transfer Model of Cardiac Ablation DOI Creative Commons
Sundeep Singh, Paola Saccomandi, Roderick Melnik

et al.

Fluids, Journal Year: 2022, Volume and Issue: 7(5), P. 180 - 180

Published: May 21, 2022

Significant research efforts have been devoted in the past decades to accurately modelling complex heat transfer phenomena within biological tissues. These modeling and analysis assisted a better understanding of intricacies associated factors that affect treatment outcomes hyperthermic therapeutic procedures. In this contribution, we report three-dimensional non-Fourier bio-heat model cardiac ablation accounts for three-phase-lags (TPL) propagation, viz., lags due flux, temperature gradient, thermal displacement gradient. Finite element-based COMSOL Multiphysics software has utilized predict distributions volumes. A comparative conducted variation considering different models. The effect variations magnitude phase systematically investigated. fidelity integrity developed evaluated by comparing results with analytical recent studies available literature. This study demonstrates importance tissue predicting more characteristics important efficient application therapies.

Language: Английский

Citations

13
Optimization of laser dosimetry based on patient-specific anatomical models for the ablation of pancreatic ductal adenocarcinoma tumor DOI Creative Commons
Pouya Namakshenas, Francesco Maria Di Matteo, Leonardo Bianchi

et al.

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: July 8, 2023

Laser-induced thermotherapy has shown promising potential for the treatment of unresectable primary pancreatic ductal adenocarcinoma tumors. Nevertheless, heterogeneous tumor environment and complex thermal interaction phenomena that are established under hyperthermic conditions can lead to under/over estimation laser efficacy. Using numerical modeling, this paper presents an optimized setting Nd:YAG delivered by a bare optical fiber (300 µm in diameter) at 1064 nm working continuous mode within power range 2-10 W. For analysis, patient-specific 3D models were used, consisting tumors different portions pancreas. The time ablating completely producing toxic effects on possible residual cells beyond margins found be 5 W 550 s, 7 8 s tail, body, head tumors, respectively. Based results, during irradiation doses, injury was not evident either 15 mm lateral distances from or nearby healthy organs. present computational-based predictions also line with previous ex vivo studies, hence, they assist therapeutic outcome ablation neoplasms prior clinical trials.

Language: Английский

Citations

7