Pub Date : 2025-12-30DOI: 10.1016/j.pacs.2025.100794
Yixiao Lin , Lukai Wang , Ian S. Hagemann , Lindsay M. Kuroki , Brooke E. Sanders , Andrea R. Hagemann , Cary Siegel , Matthew A. Powell , Quing Zhu
Diagnosing ovarian lesions is challenging because of their heterogeneous clinical presentations. Some benign ovarian conditions, such as endometriosis, can have features that mimic cancer. We use optical-resolution photoacoustic microscopy (OR-PAM) to study the differences in ovarian vasculature between cancer and various benign conditions. In this study, we converted OR-PAM vascular data into vascular graphs augmented with physical vascular properties. From 94 ovarian specimens, a custom vascular graph network (VGN) was developed to classify each graph as either normal ovary, one of three benign pathologies, or cancer. We demonstrated for the first time that, by leveraging the intrinsic similarity between vascular networks and graph constructs, VGN provides stable predictions from sampling surface areas as small as 3 mm× 0.12 mm. In diagnosing cancer, VGN achieved 79.5 % accuracy and an area under the receiver operating characteristic curve (AUC) of 0.877. Overall, VGN achieved a five-class classification accuracy of 73.4 %.
{"title":"Vascular graph network for ovarian lesion classification using optical-resolution photoacoustic microscopy","authors":"Yixiao Lin , Lukai Wang , Ian S. Hagemann , Lindsay M. Kuroki , Brooke E. Sanders , Andrea R. Hagemann , Cary Siegel , Matthew A. Powell , Quing Zhu","doi":"10.1016/j.pacs.2025.100794","DOIUrl":"10.1016/j.pacs.2025.100794","url":null,"abstract":"<div><div>Diagnosing ovarian lesions is challenging because of their heterogeneous clinical presentations. Some benign ovarian conditions, such as endometriosis, can have features that mimic cancer. We use optical-resolution photoacoustic microscopy (OR-PAM) to study the differences in ovarian vasculature between cancer and various benign conditions. In this study, we converted OR-PAM vascular data into vascular graphs augmented with physical vascular properties. From 94 ovarian specimens, a custom vascular graph network (VGN) was developed to classify each graph as either normal ovary, one of three benign pathologies, or cancer. We demonstrated for the first time that, by leveraging the intrinsic similarity between vascular networks and graph constructs, VGN provides stable predictions from sampling surface areas as small as 3 mm× 0.12 mm. In diagnosing cancer, VGN achieved 79.5 % accuracy and an area under the receiver operating characteristic curve (AUC) of 0.877. Overall, VGN achieved a five-class classification accuracy of 73.4 %.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100794"},"PeriodicalIF":6.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145939620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-29DOI: 10.1016/j.pacs.2025.100792
Refik Mert Cam , Seonyeong Park , Umberto Villa , Mark A. Anastasio
Quantitative photoacoustic computed tomography (qPACT) is a promising imaging modality for estimating physiological parameters such as blood oxygen saturation. However, developing robust qPACT reconstruction methods remains challenging due to computational demands, modeling difficulties, and experimental uncertainties. Learning-based methods have been proposed to address these issues but remain largely unvalidated. Virtual imaging (VI) studies are essential for validating such methods early in development, before proceeding to less-controlled phantom or in vivo studies. Effective VI studies must employ ensembles of stochastically generated numerical phantoms that accurately reflect relevant anatomy and physiology. Yet, most prior VI studies for qPACT relied on overly simplified phantoms. In this work, a realistic VI testbed is employed for the first time to assess a representative 3D learning-based qPACT reconstruction method for breast imaging. The method is evaluated across subject variability and physical factors such as measurement noise and acoustic aberrations, offering insights into its strengths and limitations.
{"title":"Application of a virtual imaging framework for investigating a deep learning-based reconstruction method for 3D quantitative photoacoustic computed tomography","authors":"Refik Mert Cam , Seonyeong Park , Umberto Villa , Mark A. Anastasio","doi":"10.1016/j.pacs.2025.100792","DOIUrl":"10.1016/j.pacs.2025.100792","url":null,"abstract":"<div><div>Quantitative photoacoustic computed tomography (qPACT) is a promising imaging modality for estimating physiological parameters such as blood oxygen saturation. However, developing robust qPACT reconstruction methods remains challenging due to computational demands, modeling difficulties, and experimental uncertainties. Learning-based methods have been proposed to address these issues but remain largely unvalidated. Virtual imaging (VI) studies are essential for validating such methods early in development, before proceeding to less-controlled phantom or in vivo studies. Effective VI studies must employ ensembles of stochastically generated numerical phantoms that accurately reflect relevant anatomy and physiology. Yet, most prior VI studies for qPACT relied on overly simplified phantoms. In this work, a realistic VI testbed is employed for the first time to assess a representative 3D learning-based qPACT reconstruction method for breast imaging. The method is evaluated across subject variability and physical factors such as measurement noise and acoustic aberrations, offering insights into its strengths and limitations.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"48 ","pages":"Article 100792"},"PeriodicalIF":6.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Subcutaneous adipose tissue (SAT) hemodynamics is an indicator of cardiometabolic health. Herein, we demonstrate a non-invasive approach for imaging SAT hemodynamics in humans using multispectral optoacoustic tomography (MSOT). We evaluated different SAT depots in individuals with low (< 24 kg/m²) and high (≥ 24 kg/m²) BMI, with each group consisting of 8 participants, during oral glucose challenges. Our results indicate a significant decrease in glucose-induced hyperemic responses within SAT for individuals with higher BMI, at 60 min postprandially. MSOT also revealed that abdominal SAT exhibited a more active hemodynamic status compared to femoral SAT in both groups when compared to baseline measurements. MSOT readouts were further validated against longitudinal blood tests of triglycerides, glucose, lactate, and cholesterol. We introduce MSOT as a new method for studying SAT hemodynamics across multiple depots in a single test, providing invaluable insights into SAT physiology related to BMI fluctuations and general cardiometabolic health.
{"title":"Mapping glucose-induced hemodynamics in white fat depots with label-free optoacoustics","authors":"Nikolina-Alexia Fasoula , Nikoletta Katsouli , Michael Kallmayer , Vasilis Ntziachristos , Angelos Karlas","doi":"10.1016/j.pacs.2025.100793","DOIUrl":"10.1016/j.pacs.2025.100793","url":null,"abstract":"<div><div>Subcutaneous adipose tissue (SAT) hemodynamics is an indicator of cardiometabolic health. Herein, we demonstrate a non-invasive approach for imaging SAT hemodynamics in humans using multispectral optoacoustic tomography (MSOT). We evaluated different SAT depots in individuals with low (< 24 kg/m²) and high (≥ 24 kg/m²) BMI, with each group consisting of 8 participants, during oral glucose challenges. Our results indicate a significant decrease in glucose-induced hyperemic responses within SAT for individuals with higher BMI, at 60 min postprandially. MSOT also revealed that abdominal SAT exhibited a more active hemodynamic status compared to femoral SAT in both groups when compared to baseline measurements. MSOT readouts were further validated against longitudinal blood tests of triglycerides, glucose, lactate, and cholesterol. We introduce MSOT as a new method for studying SAT hemodynamics across multiple depots in a single test, providing invaluable insights into SAT physiology related to BMI fluctuations and general cardiometabolic health.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100793"},"PeriodicalIF":6.8,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An ultra-enhanced near-infrared (NIR) photoacoustic gas sensor was developed by integrating three enhancing techniques: (a) boosting the excitation power up to 2 W via a custom-built large-mode erbium doped fiber amplifier (EDFA), (b) exploiting the acoustic resonance amplification of a hyperbolic nonlinear resonator (HNR), and (c) increasing the effective absorption path length by using a near-concentric multipass cavity (MPC) with 20 reflections. A weak CO absorption line at 1566.64 nm with the intensity of 2.074 × 10−23 cm/molecule was selected. The photoacoustic signal was enhanced 396 times. A minimum detection limit (MDL) of 190 ppb at 10 s was achieved and can be improved to be 11.4 ppb according to the Allan analysis, which was comparable to a mid-infrared (MIR) photoacoustic sensor. The ultra-enhanced NIR photoacoustic sensor is a cost-effective solution for the ppb-level trace gas detection, offering a price that is less than one-third that of MIR photoacoustic sensors.
{"title":"Detecting parts-per-billion carbon monoxide with an ultra-enhanced near-infrared photoacoustic sensor","authors":"Yaopeng Cheng , Ting Chen , Ruili Zhang , Sailing He","doi":"10.1016/j.pacs.2025.100790","DOIUrl":"10.1016/j.pacs.2025.100790","url":null,"abstract":"<div><div>An ultra-enhanced near-infrared (NIR) photoacoustic gas sensor was developed by integrating three enhancing techniques: (a) boosting the excitation power up to 2 W via a custom-built large-mode erbium doped fiber amplifier (EDFA), (b) exploiting the acoustic resonance amplification of a hyperbolic nonlinear resonator (HNR), and (c) increasing the effective absorption path length by using a near-concentric multipass cavity (MPC) with 20 reflections. A weak CO absorption line at 1566.64 nm with the intensity of 2.074 × 10<sup>−23</sup> cm/molecule was selected. The photoacoustic signal was enhanced 396 times. A minimum detection limit (MDL) of 190 ppb at 10 s was achieved and can be improved to be 11.4 ppb according to the Allan analysis, which was comparable to a mid-infrared (MIR) photoacoustic sensor. The ultra-enhanced NIR photoacoustic sensor is a cost-effective solution for the ppb-level trace gas detection, offering a price that is less than one-third that of MIR photoacoustic sensors.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100790"},"PeriodicalIF":6.8,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145799003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-12DOI: 10.1016/j.pacs.2025.100789
Chenghong Zhang , Jacopo Pelini , Stefano Dello Russo , Paolo De Natale , Mario Siciliani de Cumis , Simone Borri
Dual-comb spectroscopy is one of the most powerful techniques for multispecies trace-gas sensing, attracting growing attention in both theoretical and experimental research. Firstly demonstrated and usually applied with direct absorption spectroscopy schemes, the dual-comb approach has been successfully combined with techniques like photoacoustic (PA) and photothermal (PT) spectroscopy in recent years. These techniques have been demonstrated to be particularly attractive because of their wavelength-independent and background-free detection, two key features allowing for the achievement of unprecedented dynamic range and flexibility. The integration of these techniques with dual-comb spectroscopy allows a significant enhancement in spectral resolution and bandwidth while preserving the peculiar features of PA and PT spectroscopy. Since the first proof-of-principle demonstration of dual-comb PA spectroscopy, several solutions based on acoustic transducers and optical cavities have been proposed to enhance the final sensitivity and optimize both detection bandwidth and spectral resolution. Starting from the description of the physical principles behind dual-comb PA and PT spectroscopy, this work presents a comprehensive review of the available state-of-the-art, focusing both on the different experimental setups and on a systematic comparison of the achieved results. Finally, the main challenges and prospects will be discussed, offering insights into potential directions for further innovation.
{"title":"Dual-comb photoacoustic and photothermal spectroscopy: A comprehensive review","authors":"Chenghong Zhang , Jacopo Pelini , Stefano Dello Russo , Paolo De Natale , Mario Siciliani de Cumis , Simone Borri","doi":"10.1016/j.pacs.2025.100789","DOIUrl":"10.1016/j.pacs.2025.100789","url":null,"abstract":"<div><div>Dual-comb spectroscopy is one of the most powerful techniques for multispecies trace-gas sensing, attracting growing attention in both theoretical and experimental research. Firstly demonstrated and usually applied with direct absorption spectroscopy schemes, the dual-comb approach has been successfully combined with techniques like photoacoustic (PA) and photothermal (PT) spectroscopy in recent years. These techniques have been demonstrated to be particularly attractive because of their wavelength-independent and background-free detection, two key features allowing for the achievement of unprecedented dynamic range and flexibility. The integration of these techniques with dual-comb spectroscopy allows a significant enhancement in spectral resolution and bandwidth while preserving the peculiar features of PA and PT spectroscopy. Since the first proof-of-principle demonstration of dual-comb PA spectroscopy, several solutions based on acoustic transducers and optical cavities have been proposed to enhance the final sensitivity and optimize both detection bandwidth and spectral resolution. Starting from the description of the physical principles behind dual-comb PA and PT spectroscopy, this work presents a comprehensive review of the available state-of-the-art, focusing both on the different experimental setups and on a systematic comparison of the achieved results. Finally, the main challenges and prospects will be discussed, offering insights into potential directions for further innovation.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100789"},"PeriodicalIF":6.8,"publicationDate":"2025-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145798997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-10DOI: 10.1016/j.pacs.2025.100783
Roman Allais , Valentin Espinas , Antoine Capart , Anabela Da Silva , Olivier Boiron
Photoacoustics has gained momentum as a new medical imaging technique owing to its ability to benefit from good optical contrast and acoustic resolution. To ease transfer into clinical settings and validate the algorithms, calibrated tissue-mimicking materials (TMM) are required. This paper describes a complete photoacoustic characterisation of a line of titanium dioxide (TiO2) doped agarose hydrogels whose optical absorption (490–835 nm), reduced scattering (590–815 nm), isobaric heat capacity, mass density, speed of sound and acoustic attenuation were quantified for an agarose concentration up to 4% w/w and a TiO2 concentration ranging from 0.25 to 1 mg/mL. Empirical constitutive laws as a function of the concentrations of the components were derived, enabling the creation of TMM with tailored properties. Results showed that these phantoms are suitable candidates to mimic the photoacoustic properties of various soft tissues including intervertebral discs (IVD). Photoacoustic probings performed on an IVD-mimicking phantom and six healthy porcine discs demonstrated the ability of these TMM to accurately replicate healthy IVD properties; this could serve as a first step towards an application of photoacoustic imaging to quantifying disc degeneration.
{"title":"Design and characterisation of intervertebral disc mimicking phantoms for photoacoustic imaging","authors":"Roman Allais , Valentin Espinas , Antoine Capart , Anabela Da Silva , Olivier Boiron","doi":"10.1016/j.pacs.2025.100783","DOIUrl":"10.1016/j.pacs.2025.100783","url":null,"abstract":"<div><div>Photoacoustics has gained momentum as a new medical imaging technique owing to its ability to benefit from good optical contrast and acoustic resolution. To ease transfer into clinical settings and validate the algorithms, calibrated tissue-mimicking materials (TMM) are required. This paper describes a complete photoacoustic characterisation of a line of titanium dioxide (TiO<sub>2</sub>) doped agarose hydrogels whose optical absorption (490–835 nm), reduced scattering (590–815 nm), isobaric heat capacity, mass density, speed of sound and acoustic attenuation were quantified for an agarose concentration up to 4% w/w and a TiO<sub>2</sub> concentration ranging from 0.25 to 1 mg/mL. Empirical constitutive laws as a function of the concentrations of the components were derived, enabling the creation of TMM with tailored properties. Results showed that these phantoms are suitable candidates to mimic the photoacoustic properties of various soft tissues including intervertebral discs (IVD). Photoacoustic probings performed on an IVD-mimicking phantom and six healthy porcine discs demonstrated the ability of these TMM to accurately replicate healthy IVD properties; this could serve as a first step towards an application of photoacoustic imaging to quantifying disc degeneration.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100783"},"PeriodicalIF":6.8,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145799002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}