Journal of Biomedical Optics最新文献

{"title":"Assessment of photodynamic therapy efficacy against <i>Escherichia coli</i>-<i>Enterococcus faecalis</i> biofilms using optical coherence tomography.","authors":"Valentin V Demidov, Matthew C Bond, Natalia Demidova, Ida Leah Gitajn, Carey D Nadell, Jonathan Thomas Elliott","doi":"10.1117/1.JBO.30.3.036003","DOIUrl":"10.1117/1.JBO.30.3.036003","url":null,"abstract":"<p><strong>Significance: </strong>In orthopedic trauma surgery, spatially structured biofilm ecosystems of bacteria that colonize orthopedic devices account for up to 65% of all healthcare infections, including tens of millions of people affected in the United States. These biofilm infections typically show increased resistance to antibiotics due to their structure and composition, which contributes significantly to treatment failure. Anti-biofilm approaches are needed together with clinically usable microscopic-resolution imaging techniques for treatment efficacy assessment.</p><p><strong>Aim: </strong>Antimicrobial photodynamic therapy (aPDT) has been recently proposed to combat clinically relevant biofilms (chronic wound infections, dental biofilms, etc.) using photosensitizers excited with visible light to generate reactive oxygen species that can kill bacteria residing within pathogenic biofilms. We aim to assess the efficacy of this treatment for eradication of biofilms typically present on surfaces of orthopedic devices (e.g., intramedullary nails and osseointegrated prosthetic implants).</p><p><strong>Approach: </strong>In the first phase reported here, we test aPDT <i>in vitro</i> by growing biofilms of <i>Escherichia coli</i> and <i>Enterococcus faecalis</i> bacteria (two of the seven most common pathogens found in orthopedic trauma patients) inside soft lithography-fabricated microfluidic devices. We treat these biofilms with 5-aminolevulinic acid (5-ALA)-based aPDT, evaluate treatment efficacy with optical coherence tomography, and compare with regular clinical antibiotic treatment outcomes.</p><p><strong>Results: </strong>The antibacterial efficiency of 5-ALA-based aPDT showed nonlinear dependence on the photosensitizer concentration and the light power density, with low parameters ( <math><mrow><mn>30</mn> <mtext>  </mtext> <mi>J</mi> <mo>/</mo> <msup><mrow><mi>cm</mi></mrow> <mrow><mn>2</mn></mrow> </msup> </mrow> </math> light dose, <math><mrow><mn>100</mn> <mtext>  </mtext> <mi>mg</mi> <mo>/</mo> <mi>mL</mi></mrow> </math> 5-ALA concentration) being significantly more effective than antibiotic-treated groups ( <math><mrow><mi>p</mi> <mo><</mo> <mn>0.01</mn></mrow> </math> ), reaching 99.98% of bacteria killed at <math><mrow><mn>150</mn> <mtext>  </mtext> <mi>J</mi> <mo>/</mo> <msup><mrow><mi>cm</mi></mrow> <mrow><mn>2</mn></mrow> </msup> </mrow> </math> light dose and <math><mrow><mn>200</mn> <mtext>  </mtext> <mi>mg</mi> <mo>/</mo> <mi>mL</mi></mrow> </math> 5-ALA concentration setting.</p><p><strong>Conclusions: </strong>Performed experiments enable the translation of this portable treatment/imaging platform to the second phase of the study: aPDT treatment response assessment of biofilms grown on orthopedic hardware.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 3","pages":"036003"},"PeriodicalIF":3.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11905920/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143624897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>In vivo</i> evaluation of burn severity in skin tissue of rats using hemoglobin parameters estimated by red-green-blue imaging.","authors":"Rokeya Khatun, Kaisei Okura, Md Anowar Parvez, Kazuhiro Yashiro, Yuki Nagahama, Yasuyuki Tsunoi, Satoko Kawauchi, Daizoh Saitoh, Shunichi Sato, Izumi Nishidate","doi":"10.1117/1.JBO.30.3.036006","DOIUrl":"10.1117/1.JBO.30.3.036006","url":null,"abstract":"<p><strong>Significance: </strong>Burn injuries are a global public health problem and are estimated to cause more than 150,000 deaths annually. Even non-fatal burns result in prolonged hospitalization, disfigurement, and disability. The depth of the burn injury is crucial information for selecting adequate treatment for burns. The most common, convenient, and widely used method for assessing burn severity is visual examination, but the accuracy of this method is insufficient, at only 60% to 75%. Rapid and accurate assessment of burn severity is critical for optimal management and treatment of burn patients. Methods of burn severity assessment that are inexpensive, simple, rapid, non-contact, and non-invasive are thus needed.</p><p><strong>Aim: </strong>We aim to propose an approach to visualize the spatial distribution of burn severity using hemoglobin parameters estimated from a snapshot red-green-blue (RGB) color image and to demonstrate the feasibility of this proposed approach for differentiating burn severity in a rat model of scald burn injury.</p><p><strong>Approach: </strong>The approach to creating a spatial map of burn severity was based on canonical discriminant analysis (CDA) of total hemoglobin concentration, tissue oxygen saturation, and methemoglobin saturation as estimated from RGB color images. Burns of two different degrees of severity were created in rat dorsal skin by 10-s exposure to water maintained at 70°C and 78°C. RGB color images for the dorsal regions were acquired under anesthesia before burn injury and at 24, 48, and 72 h after injury.</p><p><strong>Results: </strong>Most areas of images in the groups with skin exposed to 70°C, 78°C, and 37°C water were classified as 70°C burn, 78°C burn, and non-burned normal skin, respectively, over 48 to 72 h. In contrast, classification images of the skin group exposed to 70°C water for 24 h showed a mixture of non-burned normal skin and 70°C burned areas, suggesting that burn severity was heterogeneous.</p><p><strong>Conclusions: </strong>The proposed approach combining RGB color imaging and CDA appears promising for differentiating 78°C burns from 70°C burns and non-burned normal skin and non-burned normal skin from 70°C and 78°C burns at 24 to 72 h after burn injury in a rat model of scald burn injury.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 3","pages":"036006"},"PeriodicalIF":3.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11931295/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143700463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fiftieth anniversary of fiber optic-based fluorometry of brain mitochondrial NADH redox state monitored <i>in vivo</i>.","authors":"Avraham Mayevsky","doi":"10.1117/1.JBO.30.S2.S23902","DOIUrl":"10.1117/1.JBO.30.S2.S23902","url":null,"abstract":"<p><strong>Significance: </strong>It is well known and accepted that the normal mitochondrial function in all cells in any organism is critical for the maintenance of cellular homeostasis. The development of <i>in vivo</i> technology to monitor mitochondrial function using nicotine-amide adenine dinucleotide (NADH) fluorescence started in the early 1950s. Until the early 1970s, the technology used for the light transfer between the light source and the monitored tissue as well as the detection system was very rigid and complicated. Monitoring of mitochondrial NADH redox states <i>in vivo</i> using the fluorescence approach could use a few techniques to transmit the light between the fluorometer and the monitored tissue.</p><p><strong>Aim: </strong>I describe the introduction of optical fibers as a tool to illuminate the monitored tissue as well as the light emitted from the tissue. I also present the advantages of using optical fibers.</p><p><strong>Approach: </strong>I describe in detail the introduction of ultraviolet (UV) transmitting optical fibers into the NADH monitoring system using various experimental protocols. The contact between the fiber optic probe and the monitored brain tissue was done by a special cannula cemented to the skull after removing a disk of bone in the parietal bone of the skull. In the same brain cannula, stainless steel electrodes, for electrocortical activity monitoring, were embedded in the wall of the light guide holder. The light guide holder was cemented to the skull by dental acrylic cement.</p><p><strong>Results: </strong>Using the fiber optic probe to monitor NADH fluorescence together with microcirculatory blood flow measured by laser Doppler flowmeter provided the new very unique types of results not published before.</p><p><strong>Conclusions: </strong>The introduction of UV-transmitting optical fibers, 50 years ago, to monitor tissue mitochondrial redox state opened up a new era in understanding the energy metabolism of tissues under <i>in vivo</i> conditions and in real time.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 Suppl 2","pages":"S23902"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836542/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced porphyrin-based hypoxia imaging by temporal oversampling of delayed fluorescence signal.","authors":"Marien I Ochoa, Arthur F Petusseau, Matthew S Reed, Petr Brůža, Brian W Pogue","doi":"10.1117/1.JBO.30.S2.S23903","DOIUrl":"10.1117/1.JBO.30.S2.S23903","url":null,"abstract":"<p><strong>Significance: </strong>Protoporphyrin IX (PpIX) delayed fluorescence (DF) is inversely related to the oxygen present in tissues and has potential as a novel biomarker for surgical guidance and real-time tissue metabolism assessment. Despite the unique promise of this technique, its successful clinical translation is limited by the low intensity emitted.</p><p><strong>Aim: </strong>We developed a systematic study of ways to increase the PpIX DF signal through acquisition sampling changes, allowing optimized imaging at video rates.</p><p><strong>Approach: </strong>To accomplish signal increase, time-gating signal compression was achieved through changes in pulse frequency and power density, using sampling rates that are faster than the decay rate of the signal. The increased signal yield was tested and validated <i>in vitro</i> and then demonstrated <i>in vivo</i>, with comparison to settings that sample the full lifetime emission decay.</p><p><strong>Results: </strong>Results <i>in vitro</i> and <i>in vivo</i> demonstrated that optimized timing could increase the detected intensity by a factor of 7. The images showed results that were superior than when sampling the full DF lifetime decay.</p><p><strong>Conclusions: </strong>The proposed timing optimization enhances PpIX-based DF real-time imaging of tissue hypoxia. By increasing sampling frequency and adjusting the acquisition gate and pulse width, the collected signal intensity improved sevenfold, demonstrated both <i>in vitro</i> and <i>in vivo</i>. The technique was shown to enable better visualization of small and anatomically challenging hypoxic structures. The improved target-to-background ratio and compatibility with pressure-enhanced sensing of tissue oxygen technique were demonstrated.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 Suppl 2","pages":"S23903"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11774257/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acetic acid enabled nuclear contrast enhancement in epi-mode quantitative phase imaging.","authors":"Zhe Guang, Amunet Jacobs, Paloma Casteleiro Costa, Zhenmin Li, Francisco E Robles","doi":"10.1117/1.JBO.30.2.026501","DOIUrl":"10.1117/1.JBO.30.2.026501","url":null,"abstract":"<p><strong>Significance: </strong>The acetowhitening effect of acetic acid (AA) enhances light scattering of cell nuclei, an effect that has been widely leveraged to facilitate tissue inspection for (pre)cancerous lesions. Here, we show that a concomitant effect of acetowhitening-changes in refractive index composition-yields nuclear contrast enhancement in quantitative phase imaging (QPI) of thick tissue samples.</p><p><strong>Aim: </strong>We aim to explore how changes in refractive index composition during acetowhitening can be captured through a novel epi-mode 3D QPI technique called quantitative oblique back-illumination microscopy (qOBM). We also aim to demonstrate the potential of using a machine learning-based approach to convert qOBM images of fresh tissues into virtually AA-stained images.</p><p><strong>Approach: </strong>We implemented qOBM, an imaging technique that allows for epi-mode 3D QPI to observe phase changes induced by AA in thick tissue samples. We focus on detecting nuclear contrast changes caused by AA in mouse brain samples. As a proof of concept, we also applied a Cycle-GAN algorithm to convert the acquired qOBM images into virtually AA-stained images, simulating the effect of AA staining.</p><p><strong>Results: </strong>Our findings demonstrate that AA-induced acetowhitening leads to significant nuclear contrast enhancement in qOBM images of thick tissue samples. In addition, the Cycle-GAN algorithm successfully converted qOBM images into virtually AA-stained images, further facilitating the nuclear enhancement process without any physical stains.</p><p><strong>Conclusions: </strong>We show that the acetowhitening effect of acetic acid induces changes in refractive index composition that significantly enhance nuclear contrast in QPI. The application of qOBM with AA, along with the use of a Cycle-GAN algorithm to virtually stain tissues, highlights the potential of this approach for advancing label-free and slide-free, <i>ex vivo</i>, and <i>in vivo</i> histology.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 2","pages":"026501"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11792252/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Er:YAG laser biofilm removal from zero-gap periodontal/peri-implant model system mimicking clinical attachment loss.","authors":"Marko Volk, Dominik Šavli, Katja Molan, Saša Terlep, Špela Levičnik-Höfferle, Mojca Trost, Boris Gašpirc, Matjaž Lukač, Matija Jezeršek, David Stopar","doi":"10.1117/1.JBO.30.2.025002","DOIUrl":"10.1117/1.JBO.30.2.025002","url":null,"abstract":"<p><strong>Significance: </strong>Here, we present a photoacoustic method to remove biofilms from periodontal and peri-implant-constrained geometries.</p><p><strong>Aim: </strong>We aim to remove biofilms from narrow periodontal and peri-implant model systems with the application of Er:YAG ultrashort laser pulses.</p><p><strong>Approach: </strong>Construction of zero-gap model system from PDMS and titanium, growth of biofilms on titanium surfaces, and removal of biofilms with Er:YAG USP, 20 mJ, 15 Hz, and 10 s were performed.</p><p><strong>Results: </strong>The results suggest that geometry, the vertical position of the laser fiber tip, and the evolution of the primary cavitation bubble significantly affect cleaning effectiveness. Cleaning was higher in the wedge part of the model system. In the zero-gap part of the model system, biofilm cleaning effectiveness was highest at the position of the laser fiber tip and decreased above and below the fiber tip. The dimension of the space in which the cavitation bubble develops determines the size and dynamics of the expanded cavitation bubble and consequently the biofilm cleaning effectiveness.</p><p><strong>Conclusions: </strong>The obtained results suggest a very good biofilm removal effectiveness in difficult-to-reach narrow geometries mimicking clinical attachment loss in the periodontal/peri-implant pocket.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 2","pages":"025002"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11853840/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143501464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Basis function model to extract the combined confocal and fall-off function from multiple optical coherence tomography A-scans.","authors":"Daniel J Phan, Martin Were, Jörn-Hendrik Weitkamp, Audrey K Bowden","doi":"10.1117/1.JBO.30.2.025003","DOIUrl":"10.1117/1.JBO.30.2.025003","url":null,"abstract":"<p><strong>Significance: </strong>Many derivatives of optical coherence tomography (OCT) rely on the depth-dependent information of the sample in the image. System depth-dependent effects, such as the confocal effect and the sensitivity fall-off, should be corrected to improve the accuracy of the images and information derived from them.</p><p><strong>Aim: </strong>We developed a new single-shot method to extract the combined confocal and fall-off functions and remove system-generated depth-dependent effects from OCT images.</p><p><strong>Approach: </strong>The combined function is modeled as a linear combination of basis functions whose coefficients are found from two or more A-scans (or B-scans) of a sample that are vertically shifted within the imaging range. No prior knowledge of the OCT system parameters or assumed form for the confocal and fall-off functions is needed.</p><p><strong>Results: </strong>The method was derived and validated with simulations and OCT images of a phantom, a biological sample, and human retina. Improvement over the Ratio Fit method was demonstrated.</p><p><strong>Conclusions: </strong>The improvement in the extraction of the combined confocal and fall-off effects by this method should lead to improved medical diagnosis through more accurate attenuation coefficient calculations. The method enables future applications of OCT where precise removal of all depth-dependent effects on OCT images is critical.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 2","pages":"025003"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11868661/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143542098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tetherless miniaturized point detector device for monitoring cortical surface hemodynamics in mice.","authors":"Anupam Bisht, Govind Peringod, Linhui Yu, Ning Cheng, Grant R Gordon, Kartikeya Murari","doi":"10.1117/1.JBO.30.S2.S23904","DOIUrl":"10.1117/1.JBO.30.S2.S23904","url":null,"abstract":"<p><strong>Significance: </strong>Several miniaturized optical neuroimaging devices for preclinical studies mimicking benchtop instrumentation have been proposed in the past. However, they are generally relatively large, complex, and power-hungry, limiting their usability for long-term measurements in freely moving animals. Further, there is limited research in the development of algorithms to analyze long-term signals.</p><p><strong>Aim: </strong>We aim to develop a cost-effective, easy-to-use miniaturized intrinsic optical monitoring system (TinyIOMS) that can be reliably used to record spontaneous and stimulus-evoked hemodynamic changes and further cluster brain states based on hemodynamic features.</p><p><strong>Approach: </strong>We present the design and fabrication of TinyIOMS ( <math><mrow><mn>8</mn> <mtext>  </mtext> <mi>mm</mi> <mo>×</mo> <mn>13</mn> <mtext>  </mtext> <mi>mm</mi> <mo>×</mo> <mn>9</mn> <mtext>  </mtext> <msup><mrow><mi>mm</mi></mrow> <mrow><mn>3</mn></mrow> </msup> </mrow> </math> , 1.2 g with battery). A standard camera-based widefield system (WFIOS) is used to validate the TinyIOMS signals. Next, TinyIOMS is used to continuously record stimulus-evoked activity and spontaneous activity for 7 h in chronically implanted mice. We further show up to 2 days of intermittent recording from an animal. An unsupervised machine learning algorithm is used to analyze the TinyIOMS signals.</p><p><strong>Results: </strong>We observed that the TinyIOMS data is comparable to the WFIOS data. Stimulus-evoked activity recorded using the TinyIOMS was distinguishable based on stimulus magnitude. Using TinyIOMS, we successfully achieved 7 h of continuous recording and up to 2 days of intermittent recording in its home cage placed in the animal housing facility, i.e., outside a controlled lab environment. Using an unsupervised machine learning algorithm ( <math><mrow><mi>k</mi></mrow> </math> -means clustering), we observed the grouping of data into two clusters representing asleep and awake states with an accuracy of <math><mrow><mo>∼</mo> <mn>91</mn> <mo>%</mo></mrow> </math> . The same algorithm was then applied to the 2-day-long dataset, where similar clusters emerged.</p><p><strong>Conclusions: </strong>TinyIOMS can be used for long-term hemodynamic monitoring applications in mice. Results indicate that the device is suitable for measurements in freely moving mice during behavioral studies synchronized with behavioral video monitoring and external stimuli.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 Suppl 2","pages":"S23904"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11922257/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of subpixel target detection and linear spectral unmixing techniques on short-wave infrared hyperspectral images of collagen phantoms.","authors":"Hsian-Min Chen, Hsin-Che Wang, Chiu-Chin Sung, Yu-Ting Hsu, Yi-Jing Sheen","doi":"10.1117/1.JBO.30.2.023518","DOIUrl":"10.1117/1.JBO.30.2.023518","url":null,"abstract":"<p><strong>Significance: </strong>We used three-dimensionally printed experimental molds and designed lard (lipid)-collagen mixed phantoms to simulate biological tissues to verify the practicality and accuracy of short-wave infrared (SWIR) hyperspectral imaging (HSI; 900 to 1700 nm), subpixel target detection (STD), and linear spectral unmixing (LSU). We provide a foundation for future development, validation, and reproducibility of hyperspectral image-processing techniques.</p><p><strong>Aim: </strong>We aim to verify the use of SWIR HSI in bionic tissue phantoms. Second, we focus on the accuracy of STD and spectral unmixing techniques in hyperspectral image processing. Finally, the penetration ability of the technology and its applications at various depths and concentrations are explored.</p><p><strong>Approach: </strong>All experiments were conducted using an SWIR (900 to 1700 nm) HSI sensor. Collagen phantoms of different thicknesses were created to test the penetration abilities. Lard (lipid) was embedded at different depths in the phantoms for STD, whereas LSU was performed on phantoms with varying collagen concentrations. The methods used included constrained energy minimization to detect the lard target and fully constrained least squares (FCLS) to estimate the abundance of collagen phantoms.</p><p><strong>Results: </strong>SWIR HSI effectively penetrated the collagen phantoms. Specifically, STD techniques can accurately detect the presence of lard (lipids) at depths of 7 to 20 mm in the collagen phantoms. Even at a depth of 68 mm, the detection accuracy was 0.907. Moreover, in the LSU analysis, the FCLS method accurately estimated the abundance of collagen phantoms at different concentrations, with a correlation coefficient of 0.9917, indicating high accuracy across different concentrations.</p><p><strong>Conclusions: </strong>This study demonstrated that SWIR HSI is highly accurate for deep target detection and LSU. This technology has great potential for use in future noninvasive biomedical diagnostic models. Collagen phantoms are valuable tools for validating HSI algorithms and provide a solid foundation for clinical applications.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 2","pages":"023518"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11853843/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143501472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperspectral imaging in neurosurgery: a review of systems, computational methods, and clinical applications.","authors":"Alankar Kotwal, Vishwanath Saragadam, Joshua D Bernstock, Alfredo Sandoval, Ashok Veeraraghavan, Pablo A Valdés","doi":"10.1117/1.JBO.30.2.023512","DOIUrl":"10.1117/1.JBO.30.2.023512","url":null,"abstract":"<p><strong>Significance: </strong>Accurate identification between pathologic (e.g., tumors) and healthy brain tissue is a critical need in neurosurgery. However, conventional surgical adjuncts have significant limitations toward achieving this goal (e.g., image guidance based on pre-operative imaging becomes inaccurate up to 3 cm as surgery proceeds). Hyperspectral imaging (HSI) has emerged as a potential powerful surgical adjunct to enable surgeons to accurately distinguish pathologic from normal tissues.</p><p><strong>Aim: </strong>We review HSI techniques in neurosurgery; categorize, explain, and summarize their technical and clinical details; and present some promising directions for future work.</p><p><strong>Approach: </strong>We performed a literature search on HSI methods in neurosurgery focusing on their hardware and implementation details; classification, estimation, and band selection methods; publicly available labeled and unlabeled data; image processing and augmented reality visualization systems; and clinical study conclusions.</p><p><strong>Results: </strong>We present a detailed review of HSI results in neurosurgery with a discussion of over 25 imaging systems, 45 clinical studies, and 60 computational methods. We first provide a short overview of HSI and the main branches of neurosurgery. Then, we describe in detail the imaging systems, computational methods, and clinical results for HSI using reflectance or fluorescence. Clinical implementations of HSI yield promising results in estimating perfusion and mapping brain function, classifying tumors and healthy tissues (e.g., in fluorescence-guided tumor surgery, detecting infiltrating margins not visible with conventional systems), and detecting epileptogenic regions. Finally, we discuss the advantages and disadvantages of HSI approaches and interesting research directions as a means to encourage future development.</p><p><strong>Conclusions: </strong>We describe a number of HSI applications across every major branch of neurosurgery. We believe these results demonstrate the potential of HSI as a powerful neurosurgical adjunct as more work continues to enable rapid acquisition with smaller footprints, greater spectral and spatial resolutions, and improved detection.</p>","PeriodicalId":15264,"journal":{"name":"Journal of Biomedical Optics","volume":"30 2","pages":"023512"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11559659/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}