PhotoacousticsPub Date : 2024-10-28DOI: 10.1016/j.pacs.2024.100658
{"title":"Quantitative volumetric photoacoustic assessment of vasoconstriction by topical corticosteroid application in mice skin","authors":"","doi":"10.1016/j.pacs.2024.100658","DOIUrl":"10.1016/j.pacs.2024.100658","url":null,"abstract":"<div><div>Topical corticosteroids manage inflammatory skin conditions via their action on the immune system. An effect of application of corticosteroids to the skin is skin blanching caused by peripheral vasoconstriction. This has been used to characterize, in some cases relative potency and also as a way to compare skin penetration. Chromameters have been used to assess skin blanching—the outcome of vasoconstriction caused by topical corticosteroids—but do not directly measure vasoconstriction. Here, we demonstrate quantitative volumetric photoacoustic microscopy (PAM) as a tool for directly assessing the vasoconstriction followed by topical corticosteroid application, noninvasively visualizing skin vasculature without any exogeneous contrast agent. We photoacoustically differentiated the vasoconstrictive ability of four topical corticosteroids in small animals through multiparametric analyses, offering detailed 3D insights into vasoconstrictive mechanisms across different skin depths. Our findings highlight the potential of PAM as a noninvasive tool for measurement of comparative vasoconstriction with potential for clinical, pharmaceutical, and bioequivalence applications.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-10-24DOI: 10.1016/j.pacs.2024.100657
{"title":"Miniature optical fiber photoacoustic spectroscopy gas sensor based on a 3D micro-printed planar-spiral spring optomechanical resonator","authors":"","doi":"10.1016/j.pacs.2024.100657","DOIUrl":"10.1016/j.pacs.2024.100657","url":null,"abstract":"<div><div>Photoacoustic spectroscopy (PAS) gas sensors based on optomechanical resonators (OMRs) have garnered significant attention for ultrasensitive trace-gas detection. However, a major challenge lies in balancing small size with high performance when developing ultrasensitive miniaturized optomechanical resonant PAS (OMR-PAS) gas sensors for space-constrained applications. Here, we present a miniature optical fiber PAS gas sensor based on a planar-spiral spring OMR (PSS-OMR) that is <em>in situ</em> 3D micro-printed on the end-face of a fiber-optic ferrule. Experimental results demonstrate that mechanical vibrational resonance can enhance the sensor's acoustic sensitivity by over two orders of magnitude. Together with a 1.4 μL non-resonant photoacoustic cell, it can detect C<sub>2</sub>H<sub>2</sub> gas concentration at the 45-ppb level, and its response is very fast approximating 0.2 seconds. This optical fiber OMR-PAS gas sensor holds great promise for the detection or monitoring of rapidly varying trace gas in many applications ranging from production process control to industrial environmental surveillance.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-10-09DOI: 10.1016/j.pacs.2024.100656
{"title":"Application of multispectral optoacoustic tomography for lower limb musculoskeletal sports injuries in adults","authors":"","doi":"10.1016/j.pacs.2024.100656","DOIUrl":"10.1016/j.pacs.2024.100656","url":null,"abstract":"<div><div>Compositional changes in relation to musculoskeletal injuries are difficult to measure non-invasively. This study aims to use non-invasive label-free imaging with Multispectral Optoacoustic Tomography (MSOT) to evaluate compositional changes with injury. Five different patient groups were examined, covering diagnoses of Achilles or patellar tendinopathy, Achilles tendon rupture and gastrocnemius muscle strain injury. Injured and contralateral limbs were imaged using a commercial MSOT device. Hemoglobin, collagen, and lipid contents were estimated. Some patients were examined before and after exercise. Hemoglobin measures had high reproducibility and displayed systematic changes in response to exercise. The content and exercise response of hemoglobin was equal on both limbs. In contrast, collagen and lipid measures were inconsistent and did not display the expected distribution. In conclusion, MSOT is applicable to imaging of hemoglobin in musculoskeletal injuries, providing complimentary information to conventional ultrasound, but applicability to other components like collagen and lipids could not be shown.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-10-09DOI: 10.1016/j.pacs.2024.100655
{"title":"Calibration-free infrared absorption spectroscopy using cantilever-enhanced photoacoustic detection of the optical power","authors":"","doi":"10.1016/j.pacs.2024.100655","DOIUrl":"10.1016/j.pacs.2024.100655","url":null,"abstract":"<div><div>We report on sensitive tunable laser absorption spectroscopy using a multipass gas cell and a solid-state photoacoustic optical power detector. Unlike photoacoustic spectroscopy (PAS), this method readily allows a low gas pressure for high spectral selectivity and a free gas flow for continuous measurements. Our photoacoustic optical power detector has a large linear dynamic range and can be used at almost any optical wavelength, including the middle infrared and THz regions that are challenging to cover with traditional optical detectors. Furthermore, our approach allows for compensation of laser power drifts with a single detector. As a proof of concept, we have measured very weak CO<sub>2</sub> absorption lines at 9.2 µm wavelength and achieved a normalized noise equivalent absorption (NNEA) of 2.35·10<sup>−9</sup> Wcm<sup>−1</sup>Hz<sup>−1/2</sup> with a low-power quantum cascade laser. The absolute value of the gas absorption coefficient is obtained directly from the Beer-Lambert law, making the technique calibration-free.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-27DOI: 10.1016/j.pacs.2024.100652
{"title":"Kinetic cooling in mid-infrared methane photoacoustic spectroscopy: A quantitative analysis via digital twin verification","authors":"","doi":"10.1016/j.pacs.2024.100652","DOIUrl":"10.1016/j.pacs.2024.100652","url":null,"abstract":"<div><div>This study presents a detailed quantitative analysis of kinetic cooling in methane photoacoustic spectroscopy, leveraging the capabilities of a digital twin model. Using a quantum cascade laser tuned to 1210.01 cm⁻¹, we investigated the effects of varying nitrogen-oxygen matrix compositions on the photoacoustic signals of 15 ppmV methane. Notably, the photoacoustic signal amplitude decreased with increasing oxygen concentration, even falling below the background signal at oxygen levels higher than approximately 6 %V. This phenomenon was attributed to kinetic cooling, where thermal energy is extracted from the surrounding gas molecules rather than added, as validated by complex vector analysis using a previously published digital twin model. The model accurately reproduced complex signal patterns through simulations, providing insights into the underlying molecular mechanisms by quantifying individual collision contributions. These findings underscore the importance of digital twins in understanding the fundamentals of photoacoustic signal generation at the molecular level.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-27DOI: 10.1016/j.pacs.2024.100654
{"title":"Laser ultrasound wave pattern analysis for efficient defect detection in samples with curved surfaces","authors":"","doi":"10.1016/j.pacs.2024.100654","DOIUrl":"10.1016/j.pacs.2024.100654","url":null,"abstract":"<div><div>Many production processes involve curved sample surfaces, such as welding or additive manufacturing. These pose new challenges to characterization methods for quality inspection, which are usually optimized for flat extended sample geometries. In this paper, we present a laser ultrasound (LUS) method that can be used to efficiently detect defects (e.g., voids), without extensive scanning effort and without a prior knowledge of the defect location, in finite samples with curved surfaces. The developed method starts with generalized simulations of the LUS wave patterns in samples with varying radii of curvature and width as well as varying excitation size and mechanism (thermoelastic or ablative). Based on the wave pattern analysis, it is possible to predict how every point in the weld can be reached with only few excitation spots. In a second step, we assume a grid of finite size defects at locations at which such voids are most likely formed and perform a thorough simulation analysis that is based on B-Scans to find a few pairs of excitation–detection points most favorable for finding defects anywhere in the weld seam. These results are then compared to the wave pattern analysis, discussing similarities and deviations from the predictions. In a final step, the simulations are compared to experimental results, verifying the almost threefold increase in the detectability of defects by choosing the predicted optimal excitation–detection positions. It is expected that this method will significantly improve the reliability and time efficiency of detecting internal defects in samples with curved surfaces in potential industrial applications.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-23DOI: 10.1016/j.pacs.2024.100653
{"title":"Machine learning radiomics based on intra and peri tumor PA/US images distinguish between luminal and non-luminal tumors in breast cancers","authors":"","doi":"10.1016/j.pacs.2024.100653","DOIUrl":"10.1016/j.pacs.2024.100653","url":null,"abstract":"<div><h3>Purpose</h3><div>This study aimed to evaluate a radiomics model using Photoacoustic/ultrasound (PA/US) imaging at intra and peri-tumoral area to differentiate Luminal and non-Luminal breast cancer (BC) and to determine the optimal peritumoral area for accurate classification.</div></div><div><h3>Materials and methods</h3><div>From February 2022 to April 2024, this study continuously collected 322 patients at Shenzhen People’s Hospital, using standardized conditions for PA/US imaging of BC. Regions of interest were delineated using ITK-SNAP, with peritumoral regions of 2 mm, 4 mm, and 6 mm automatically expanded using code from the Pyradiomic package. Feature extraction was subsequently performed using Pyradiomics. The study employed Z-score normalization, Spearman correlation for feature correlation, and LASSO regression for feature selection, validated through 10-fold cross-validation. The radiomics model integrated intra and peri-tumoral area, evaluated by receiver operating characteristic curve(ROC), Calibration and Decision Curve Analysis(DCA).</div></div><div><h3>Results</h3><div>We extracted and selected features from intratumoral and peritumoral PA/US images regions at 2 mm, 4 mm, and 6 mm. The comprehensive radiomics model, integrating these regions, demonstrated enhanced diagnostic performance, especially the 4 mm model which showed the highest area under the curve(AUC):0.898(0.78–1.00) and comparably high accuracy (0.900) and sensitivity (0.937). This model outperformed the standalone clinical model and combined clinical-radiomics model in distinguishing between Luminal and non-Luminal BC, as evidenced in the test set results.</div></div><div><h3>Conclusion</h3><div>This study developed a radiomics model integrating intratumoral and peritumoral at 4 mm region PA/US model, enhancing the differentiation of Luminal from non-Luminal BC. It demonstrated the diagnostic utility of peritumoral characteristics, reducing the need for invasive biopsies and aiding chemotherapy planning, while emphasizing the importance of optimizing tumor surrounding size for improved model accuracy.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-21DOI: 10.1016/j.pacs.2024.100651
{"title":"Photoacoustic thermal-strain measurement towards noninvasive and accurate temperature mapping in photothermal therapy","authors":"","doi":"10.1016/j.pacs.2024.100651","DOIUrl":"10.1016/j.pacs.2024.100651","url":null,"abstract":"<div><div>Photothermal therapy is a promising tumor treatment approach that selectively eliminates cancer cells while assuring the survival of normal cells. It transforms light energy into thermal energy, making it gentle, targeted, and devoid of radiation. However, the efficacy of treatment is hampered by the absence of accurate and noninvasive temperature measurement method in the therapy. Therefore, there is a pressing demand for a noninvasive temperature measurement method that is real-time and accurate. This article presents one such attempt based on thermal strain photoacoustic (PA) temperature measurement. The method was first modelled, and a circular array-based photoacoustic photothermal system was developed. Experiments with Indian ink as tumor simulants suggest that the temperature monitoring in this work achieves a precision of down to 0.3 °C. Furthermore, it is possible to accomplish real-time temperature imaging, providing accurate two-dimensional temperature mapping for photothermal therapy. Experiments were also conducted on human fingers and nude mice, validating promising potentials of the proposed method for practical implementations.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-18DOI: 10.1016/j.pacs.2024.100650
{"title":"Highly sensitive and miniaturized microcone-curved resonant photoacoustic cavity for trace gas detection","authors":"","doi":"10.1016/j.pacs.2024.100650","DOIUrl":"10.1016/j.pacs.2024.100650","url":null,"abstract":"<div><p>This paper proposes a novel microcone-curved resonant photoacoustic cell (MCR-PAC) for highly sensitive trace gas detection. The MCR-PAC features with microcone-curved resonant region and cylindrical buffer chamber, which dominates the photoacoustic signal amplification. By introducing the hyperbolic eccentricity as a new optimization dimension, the quality factor of the MCR-PAC is remarkably strengthened to enhance the acoustic pressure amplitude. At an eccentricity value of 5, the volume of the photoacoustic resonant cavity is approximately 0.23 cm<sup>3</sup>. Targeting trace acetylene, the system achieves a minimum detection limit of 1.41 ppb with an integration time of 290 s, corresponding normalized noise equivalent absorption coefficient is 1.88×10<sup>−9</sup> W·cm<sup>−1</sup>·Hz<sup>−1/2</sup>. Compared to the traditional T-type PAC, the overall performance of MCR-PAC has been enhanced nearly fourfold. With its compact millimeter-scale dimensions and high sensitivity, the MCR-PAC demonstrates extensive potential for application in environmental monitoring and breath diagnostics.</p></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213597924000673/pdfft?md5=7e2d70b37976e55f3ecca89ade8f4c90&pid=1-s2.0-S2213597924000673-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PhotoacousticsPub Date : 2024-09-17DOI: 10.1016/j.pacs.2024.100649
{"title":"Bornite (Cu5FeS4) nanocrystals as an ultrasmall biocompatible NIR-II contrast agent for photoacoustic imaging","authors":"","doi":"10.1016/j.pacs.2024.100649","DOIUrl":"10.1016/j.pacs.2024.100649","url":null,"abstract":"<div><div>In this study, we demonstrate the potential of the bornite crystal structure (Cu<sub>5</sub>FeS<sub>4</sub>) of copper iron sulfide as a second near infrared (NIR-II) photoacoustic (PA) contrast agent. Bornite exhibits comparable dose-dependent biocompatibility to copper sulfide nanoparticles in a cell viability study with HepG2 cells, while exhibiting a 10-fold increase in PA amplitude. In comparison to other benchmark contrast agents at similar mass concentrations, bornite demonstrated a 10× increase in PA amplitude compared to indocyanine green (ICG) and a 5× increase compared to gold nanorods (AuNRs). PA signal was detectable with a light pathlength greater than 5 cm in porcine tissue phantoms at bornite concentrations where in vitro cell viability was maintained. In vivo imaging of mice vasculature resulted in a 2× increase in PA amplitude compared to AuNRs. In summary, bornite is a promising NIR-II contrast agent for deep tissue PA imaging.</div></div>","PeriodicalId":56025,"journal":{"name":"Photoacoustics","volume":null,"pages":null},"PeriodicalIF":7.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2213597924000661/pdfft?md5=9e8a32cda5a2ee4adff2999b40a2092d&pid=1-s2.0-S2213597924000661-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}