Photoacoustics最新文献

{"title":"Frequency domain laser ultrasound for inertial confinement fusion target wall thickness measurements","authors":"Martin Ryzy ,&nbsp;Guqi Yan ,&nbsp;Clemens Grünsteidl ,&nbsp;Georg Watzl ,&nbsp;Kevin Sequoia ,&nbsp;Pavel Lapa ,&nbsp;Haibo Huang","doi":"10.1016/j.pacs.2026.100801","DOIUrl":"10.1016/j.pacs.2026.100801","url":null,"abstract":"<div><div>In inertial confinement fusion experiments hollow, spherical mm-sized capsules are used as a container for nuclear fuel. To achieve maximum implosion efficiency, a perfect capsule geometry is required. This paper presents a wall thickness measurement method based on zero-group velocity guided elastic wave resonances. They are measured with a non-destructive, contactless frequency domain laser ultrasound microscopy system. Wall thickness measurements along the equator of a high-density carbon capsule with a diameter of around <span><math><mrow><mn>2</mn><mspace></mspace><mstyle><mi>m</mi><mi>m</mi></mstyle></mrow></math></span> and a wall thickness of around <span><math><mrow><mn>80</mn><mspace></mspace><mstyle><mi>µ</mi><mi>m</mi></mstyle></mrow></math></span> excellently agree with infrared interferometry reference measurements. In addition, the multi-resonant nature of a spherical shell is studied by complementing experimental observations with plate dispersion calculations and finite element wave propagation simulations. The presented method is scalable and can be applied to a broad range of target materials, including metals, or metal-doped targets.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"48 ","pages":"Article 100801"},"PeriodicalIF":6.8,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146039603","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}

{"title":"Real-time in Vivo monitoring of photosynthesis in individual leaves by frequency-locked quartz-enhanced photoacoustic spectroscopy","authors":"Surui Liu,&nbsp;Lu Qin,&nbsp;Chongqiu Zhou,&nbsp;Juncheng Lu,&nbsp;Wen Liu,&nbsp;Jie Shao","doi":"10.1016/j.pacs.2026.100802","DOIUrl":"10.1016/j.pacs.2026.100802","url":null,"abstract":"<div><div>This paper presents a method for real-time measurement of <em>in vivo</em> leaves photosynthetic rates using quartz-enhanced photoacoustic spectroscopy (QEPAS) with first-harmonic frequency- locking (1f-locking). A compact gas sensor structure was constructed by integrating an in-plane acoustic micro-resonator (AmR) with a commercial 30.720 kHz quartz tuning fork (QTF). The DFB laser’s output wavelength was locked to the CO₂ absorption line at 4991.26 cm⁻¹ via 1f-locking, enabling real-time monitoring of CO₂ uptake during leaf photosynthesis. Compared to the scanning mode, the standard deviation (STD) in 1f-locking mode is significantly reduced, with detection sensitivity increased by nearly threefold. The system achieved a 1 s measurement cycle, with detection linearity R² = 0.999. When the integration time is 127 s, the minimum detection limit (MDL) is 2.44 ppmv. The normalized noise equivalent absorption coefficient (NNEA) is 4.78 × 10⁻⁹ cm⁻¹·W·Hz^−1/2. Results obtained align with reported photosynthetic rate ranges, validating the system’s feasibility. This system provides a portable, highly sensitive, rapid, and reliable method for leaves photosynthetic rate determination.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"48 ","pages":"Article 100802"},"PeriodicalIF":6.8,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146039604","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}

{"title":"Early identification of umbilical blood flow restriction and maternal placental hypoperfusion with photoacoustic imaging","authors":"Luting Zhang ,&nbsp;Mengyu Zhou ,&nbsp;Qiufang Ouyang ,&nbsp;Fan Meng ,&nbsp;Zhen Yuan ,&nbsp;Min Chen ,&nbsp;Zongjie Weng ,&nbsp;Jian Zhang","doi":"10.1016/j.pacs.2026.100803","DOIUrl":"10.1016/j.pacs.2026.100803","url":null,"abstract":"<div><div>In clinical practice, the prompt and accurate identification of acute fetal distress (AFD) is critical. Although cardiotocography and ultrasonography are the cornerstone clinical tools for fetal monitoring, they cannot quantitatively assess fetal cerebral hypoxia and carry inherent risks of underdiagnosis or false-positive interpretations. This study evaluates photoacoustic imaging (PAI) for early AFD detection. In mouse models, oxygen saturation (sO₂) in the fetal brain and placenta was measured using PAI, demonstrating a significant sO₂ decrease following placental blood flow obstruction - with more pronounced reductions observed in complete versus partial restriction cases. Crucially, a novel two-step PAI approach differentiated placental hypoperfusion from umbilical cord obstruction by analyzing distinct sO₂ patterns in both placenta and fetal brain tissues. This distinction is clinically vital, as placental and cord-related AFD require different urgent interventions. PAI’s ability to pinpoint the underlying cause highlights its potential for guiding precise treatment decisions.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"48 ","pages":"Article 100803"},"PeriodicalIF":6.8,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080584","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}

{"title":"Generative adversarial networks-enhanced quasi-square wave modulated photoacoustic spectroscopy: A highly sensitive NH3 detection method under strong background noise","authors":"Yanfeng Li ,&nbsp;Xueshi Zhang ,&nbsp;Lixian Liu ,&nbsp;Huiting Huan ,&nbsp;Boli Su ,&nbsp;Zongxuan Mou ,&nbsp;Yize Liang ,&nbsp;Huailiang Xu ,&nbsp;Andreas Mandelis","doi":"10.1016/j.pacs.2026.100799","DOIUrl":"10.1016/j.pacs.2026.100799","url":null,"abstract":"<div><div>We present a photoacoustic spectroscopy reconstruction generative adversarial network (PASR-GAN), which boosts the NH₃ detection performance of the photoacoustic spectroscopy sensor through collaborative optimization of the light modulation mode, especially under strong background noise. Instead of a sinusoidal wave, a quasi-square wave is used as the modulation waveform due to its higher signal excitation efficiency, achieving a 37 % signal enhancement. PASR-GAN suppresses noise and reconstructs corresponding clean signals by establishing a nonlinear mapping between noisy and clean signals, overcoming the limitations of traditional algorithms that rely on prior assumptions and are difficult to eliminate complex noises. For inherent noise and sudden noise, PASR-GAN exhibits 7.5 times and 172 times noise reduction, respectively. A detection limit of 32.44 ppb and a 0.99999 linear coefficient of determination within the 0<strong>–</strong>1000 ppm range demonstrate the concentration prediction capability of PASR-GAN. PASR-GAN provides a robust, data-driven approach for signal reconstruction under complex noise environments.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100799"},"PeriodicalIF":6.8,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037752","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}

{"title":"Ultrafast subwavelength CVD-graphene nanoheater for the generation of broadband photoacoustic waves","authors":"A. Rezaei ,&nbsp;D.A. Pereira ,&nbsp;G.V. Bianco ,&nbsp;G. Bruno ,&nbsp;A. Mrzel ,&nbsp;L.G. Arnaut ,&nbsp;C. Serpa ,&nbsp;M. Jezeršek ,&nbsp;D. Vella","doi":"10.1016/j.pacs.2026.100796","DOIUrl":"10.1016/j.pacs.2026.100796","url":null,"abstract":"<div><div>Efficient operation of light-to-pressure transducers and flexible fabrication on demand are key factors for the use of photoacoustic devices in various biomedical disciplines. Graphene layers can be grown at wafer scale and transferred to any surface geometry, providing a versatile approach for the development of photoacoustic emitters with a large and nearly uniform thermal interface. Here we report the picosecond excitation of a photoacoustic emitter consisting of a large-area, 10-layer graphene grown by chemical vapour deposition and encapsulated with a polydimethylsiloxane. The theoretical and experimental studies address the generation of broadband ultrasounds upon excitation with nanosecond and picosecond laser pulses, showing how the multilayer graphene can serve as an ultrafast nanoheater to drive efficient expansion of the adjacent polymer layer in the picosecond regime. The picosecond excitation results in a sharper acoustic waveform, and the pressure evolution time is twice as short with a 30 ps excitation as with a 6 ns pulse, thus satisfying the thermal and stress confinement conditions, while energy loss occurs with nanosecond excitation. We experimentally observed that the 10-layer graphene/polydimethylsiloxane generates a high-frequency photoacoustic wave with a bandwidth of about 110 MHz at −6 dB, increasing to 250 MHz at −20 dB, due to stress confinement, increased thermal interface, and ultrafast dynamics. The peak pressure of 0.85 MPa in 3.4 nm thick graphene multilayers (∼20 % absorption of 40 mJ cm^–2) is remarkably high, demonstrating its potential as a photoacoustic material and the advantages of combining picosecond excitation with large-area graphene in wave transmission technologies.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100796"},"PeriodicalIF":6.8,"publicationDate":"2026-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977569","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}

{"title":"Attention-driven complementary information fusion network for sparse photoacoustic image reconstruction","authors":"Yixin Lai ,&nbsp;Qiong Zhang ,&nbsp;Zhengnan Yin","doi":"10.1016/j.pacs.2026.100797","DOIUrl":"10.1016/j.pacs.2026.100797","url":null,"abstract":"<div><div>Photoacoustic tomography (PAT) is an emerging biomedical imaging modality that uniquely combines high spatial resolution with deep tissue penetration in a non-invasive manner, holding significant promise for diverse applications. However, image reconstruction quality in PAT severely degrades under limited-view data acquisition scenarios, such as those imposed by the physical constraints of intracavitary imaging. Conventional reconstruction methods (e.g., Delay-and-Sum, DAS) under these conditions typically yield images plagued by severe artifacts and loss of fine structural details. While deep learning (DL) approaches offer some improvement, existing post-processing methods still struggle to accurately recover intricate anatomical features from severely undersampled, limited-view data, often resulting in blurred details or persistent artifacts. To address these critical limitations, we propose DUAFF-Net, a novel dual-stream deep learning architecture. DUAFF-Net uniquely processes two complementary input representations in parallel: 1) conventional DAS reconstructions, and 2) pixel-wise interpolated raw data. The network employs a sophisticated two-stage feature fusion strategy to maximize information extraction and synergy. In the first stage, the Multi-scale Information Aggregation and Feature-refinement Module (MIAF-Module) enables early-stage cross-modal information complementarity and feature enhancement. Subsequently, the Global Context and Deep Fusion Module (GCDF-Module) focuses on holistic feature optimization and deep integration across the streams. These modules work synergistically to progressively refine the reconstruction. Extensive experiments on simulated PAT datasets of retinal vasculature and complex brain structures, as well as an <em>in vivo</em> mouse abdomen dataset, demonstrate that DUAFF-Net robustly generates high-quality images even under highly incomplete data conditions. Quantitative evaluation shows that DUAFF-Net achieves substantial improvements over the standard DAS algorithm, with gains of ∼18.38 dB in Peak Signal-to-Noise Ratio (PSNR) and ∼0.69 in Structural Similarity Index (SSIM). Furthermore, DUAFF-Net consistently outperforms other state-of-the-art DL-based reconstruction models across multiple metrics, demonstrating its superior capability in preserving fine details and suppressing artifacts, thereby establishing comprehensive performance advantages for limited-view PAT reconstruction.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100797"},"PeriodicalIF":6.8,"publicationDate":"2026-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977570","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}

{"title":"Blood-mimicking dye phantoms for evaluating photoacoustic oximetry accuracy","authors":"Yong Zhou ,&nbsp;Zixin Wang ,&nbsp;Keith A. Wear ,&nbsp;T. Joshua Pfefer ,&nbsp;Jesse V. Jokerst ,&nbsp;William C. Vogt","doi":"10.1016/j.pacs.2026.100795","DOIUrl":"10.1016/j.pacs.2026.100795","url":null,"abstract":"<div><div>Many proposed clinical applications of photoacoustic imaging (PAI) rely on relative or absolute measurements of blood oxygen saturation (sO2), and evaluation of oximetry measurement accuracy is crucial for assessing device performance. Available bench test methods use phantoms connected to blood flow circuits with tunable oxygenation, but these methods are complex, costly, and pose biohazard safety risks. To address these issues, we have developed stable and tunable blood-mimicking solutions using binary mixtures of commercially available near-infrared organic dyes (NIR746A and IRA980) to enable non-biological phantom-based PAI oximetry test methods. We used spectrophotometry and a custom PA spectroscopy system to characterize dye extinction and PA response at 750 nm and 850 nm, then formulated various dye recipes mimicking sO2 levels from 40 % to 100 %. We then used a custom PAI system to image breast-mimicking polyacrylamide hydrogel phantoms with embedded tubes injected with static volumes of either dye solutions or bovine blood deoxygenated using sodium dithionite. Phantom testing with dyes produced similar performance metrics to blood, with root-mean-squared difference (RMSD) values between photoacoustic sO2 and reference sO2 of 6–17 % for blood and 4–18 % for dyes, sensitivity (slope of the regression line) ranged from 0.4 to 0.7 for blood and 0.4–0.9 for dyes, and depth-averaged bias ranged from 4 % to 17 % for blood and 3–10 % for dyes. These blood-mimicking dyes may offer a simpler, cheaper, safer, and more stable approach to evaluate PAI oximetry accuracy compared to traditional blood flow phantoms. This tool could facilitate establishment of less burdensome and more reproducible phantom-based PAI test methods, ultimately expediting clinical adoption of PAI technology.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":"47 ","pages":"Article 100795"},"PeriodicalIF":6.8,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037751","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}

{"title":"Vascular graph network for ovarian lesion classification using optical-resolution photoacoustic microscopy","authors":"Yixiao Lin ,&nbsp;Lukai Wang ,&nbsp;Ian S. Hagemann ,&nbsp;Lindsay M. Kuroki ,&nbsp;Brooke E. Sanders ,&nbsp;Andrea R. Hagemann ,&nbsp;Cary Siegel ,&nbsp;Matthew A. Powell ,&nbsp;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}

{"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 ,&nbsp;Seonyeong Park ,&nbsp;Umberto Villa ,&nbsp;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}

{"title":"Mapping glucose-induced hemodynamics in white fat depots with label-free optoacoustics","authors":"Nikolina-Alexia Fasoula ,&nbsp;Nikoletta Katsouli ,&nbsp;Michael Kallmayer ,&nbsp;Vasilis Ntziachristos ,&nbsp;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 (&lt; 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}