European Conference on Biomedical Optics最新文献_第8页

Progress on the interpretation of optoretinogram (ORG): effect of water permeability of outer retina barriers 视网膜光图(ORG)的解释进展:视网膜外屏障水渗透性的影响

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2671027

R. Zawadzki, Pengfei Zhang, S. Karlen, E. Pijewska, R. Meleppat, R. Jonnal, E. Pugh

{"title":"Progress on the interpretation of optoretinogram (ORG): effect of water permeability of outer retina barriers","authors":"R. Zawadzki, Pengfei Zhang, S. Karlen, E. Pijewska, R. Meleppat, R. Jonnal, E. Pugh","doi":"10.1117/12.2671027","DOIUrl":"https://doi.org/10.1117/12.2671027","url":null,"abstract":"The development of functional retinal imaging is of great interest to clinical and experimental ophthalmology because it should improve current clinical practice that relies on a simple evaluation of disease-related changes in retinal morphology. In this presentation, we will review our recent progress in the measurements and interpretation of Optoretinograms (ORG). The ORG comprises light-dependent changes in photoreceptor outer segment length and scattering measured in vivo with submicrometer-resolution by Optical Coherence Tomography (OCT). Our recent data confirm that the mechanisms underlying “slow” ORG response is that extreme phototransduction increases osmotic pressure in the outer segment, driving water entry and swelling to restore osmotic balance. Water movement between different retinal layers was quantified by OCT measurements, and analysis of retinal layer thickness dynamics provided estimates of the water permeability of key barriers between the Choriocapillaris (CC) and photoreceptors, viz., of the CC cell membrane, Bruch’s Membrane (BrM), the RPE layer, and the rod plasma membrane. A model proposed to link the changes in refractive index caused by the osmotically driven water movement between the CC lumen and the outer segment during the ORG predicts the observed BrM scattering changes. Overall, the results and modeling provide new insights into critical water barriers of the posterior eye and an experimental and theoretical toolkit for measuring their permeabilities.","PeriodicalId":278089,"journal":{"name":"European Conference on Biomedical Optics","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126404029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimizing the classification of biological tissues using polarized data supported by machine learning 利用机器学习支持的极化数据优化生物组织分类

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2673758

I. Estévez, Mónica Canabal-Carbia, Carla Rodríguez, J. Campos, Á. Lizana

引用次数: 0

Ultra-widefield high-resolution OCT angiography of rodent retina 啮齿动物视网膜的超宽视场高分辨率OCT血管造影

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2671534

Yali Jia

引用次数: 0

Raman spectroscopy in in vitro cell cultures: understanding chemoresistance 体外细胞培养中的拉曼光谱:了解化学耐药性

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2670317

Parikshit J. Patel, Abhiram Natu, Arti R. Hole, Sanjay Gupta, C. Murali Krishna

{"title":"Raman spectroscopy in in vitro cell cultures: understanding chemoresistance","authors":"Parikshit J. Patel, Abhiram Natu, Arti R. Hole, Sanjay Gupta, C. Murali Krishna","doi":"10.1117/12.2670317","DOIUrl":"https://doi.org/10.1117/12.2670317","url":null,"abstract":"Over the past several decades, research and innovations in the field of cancer therapy have garnered significant attention globally. Despite these advancements, incidences of recurrence and relapse have been a major obstacle in cancer treatment. Moreover, the underlined cause of death due to cancer is largely due to delayed detection and therapy resistance. It is evident that early detection and prediction of therapy resistance can benefit in designing personalized treatment regimen and better prognosis. Therefore, vibrational spectroscopic techniques such as Raman spectroscopy (RS) are being explored. RS is a rapid, inexpensive and objective method that extracts useful biochemical information. It provides a global molecular fingerprint of the cellular milieu, highlighting the physiological state of the system. In this study, we have evaluated RS to characterize and delineate chemoresistant and parental cell types of cervical and liver cancer cell lines HeLa, SiHa, HepG2 and Hep3B respectively. Doxorubicin-induced resistant cell lines were developed using incremental drug dosing method to obtain a desirable resistance index value. Raman spectra of these cell lines were recorded to understand biochemical profiles and stratify resistant and parental groups using confocal Raman microscope (WITec alpha 300R) and were preprocessed. Mean spectra were computed and were subjected to multivariate analyses such as Principal Component Analysis (PCA) and Principal Component based Linear Discriminant Analysis (PC-LDA). Key spectral features such as protein, DNA, lipid and cytochrome levels were observed higher in the resistant cell populations than that in corresponding parental cell populations. PC-LDA results showed good classification between parental and resistant cell populations for all the cell lines. Thus, RS can be prospectively explored in clinical settings for better stratification of cancer patients, enabling effective therapeutic outcomes.","PeriodicalId":278089,"journal":{"name":"European Conference on Biomedical Optics","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124535037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Direct measurements of diffusive samples by random lasing 用随机激光直接测量扩散样品

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2670943

F. Tommasi, L. Fini, F. Martelli, S. Cavalieri

{"title":"Direct measurements of diffusive samples by random lasing","authors":"F. Tommasi, L. Fini, F. Martelli, S. Cavalieri","doi":"10.1117/12.2670943","DOIUrl":"https://doi.org/10.1117/12.2670943","url":null,"abstract":"The invention of the random laser has opened a new frontier in optics, providing also the opportunity to explore new possibilities in the field of sensing. Random lasing have been proposed as promising opportunity to extend the potentiality given by optical sensing strategies, in particular in the field of the measurement of diffusive properties. Compared to the other used strategies, random laser-base systems has the advantage to show amplification of the signal by stimulated emission, as well as spectral modification. In particular, a non-invasive type of random laser sensor, that exploits a transparent physical separation between the gain material and the diffusive sample, has been reported. Here we present an improvement of the experimental setup used for such a kind of sensor. By the use of a optical fibers system and a couple of twin sensors, we report an enhancement of the accuracy, stability, reproducibility, as well an measurement method easy to perform, without resorting to complicated numerical or analytic inversion procedures. Since the possibility to perform local direct measurement on diffusive samples, such a “active” method can be a promising strategy in the field of biomedical optics and for non-invasive diagnostic purposes.","PeriodicalId":278089,"journal":{"name":"European Conference on Biomedical Optics","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114530199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-cost speckle reduction method for OCT B-scan imaging 低成本的斑点减少方法用于OCT b扫描成像

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2670352

J. Camard, M. Marques, M. Aquilina, G. Silvestri, D. Griffin, A. Podoleanu

引用次数: 0

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2670891

Neža Golmajer Zima, N. Verdel, B. Majaron

{"title":"Age-related changes of dermal scattering coefficient assessed using a noninvasive optical technique","authors":"Neža Golmajer Zima, N. Verdel, B. Majaron","doi":"10.1117/12.2670891","DOIUrl":"https://doi.org/10.1117/12.2670891","url":null,"abstract":"We investigate age-related changes of the dermal reduced scattering coefficient in human skin using a recently introduced methodology for non-invasive characterization of structure and composition of skin in vivo. The approach combines pulsed photothermal radiometry (PPTR) with diffuse reflectance spectroscopy (DRS) in visible part of the spectrum. The experimental data are fitted simultaneously with the respective predictions of a dedicated numerical model of light and heat transport in healthy skin (i.e., inverse Monte Carlo). For this purpose, we apply a four-layer optical skin model consisting of epidermis, upper dermis, lower dermis, and subcutaneous adipose tissue. The study is based on 24 measurements of test sites on the ventral side of the forearm in 9 women and 9 men with healthy fair skin, between 20 and 65 years old. Linear regression analysis of the assessed dermal reduced scattering coefficient values at 500 nm (ader) indicated no significant variation with the person’s age. Meanwhile, strong correlations of ader with the blood contents in both papillary and reticular dermis were observed. Separating the respective contributions of these three variables using multiple linear regression (MLR) analysis revealed a highly significant influence of person’s age on ader (with Pearson’s correlation coefficient r = –0.55 and p < 0.0001). Specifically, by excluding the direct influence of the dermal blood contents, ader decreases with age by approximately 0.2 mm-1 per decade. In addition, the values obtained for older persons are in good agreement with the results from a large cohort study performed by Jonasson et al. (J. Biomed. Opt. 2018).","PeriodicalId":278089,"journal":{"name":"European Conference on Biomedical Optics","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124861842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In vivo optophysiology in rodent eyes using phase-sensitive optical coherence tomography 用相敏光学相干断层扫描研究啮齿动物眼睛的体内光生理

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2672175

Bingyao Tan, Huakun Li, V. Barathi, L. Schmetterer, Tong Ling

{"title":"In vivo optophysiology in rodent eyes using phase-sensitive optical coherence tomography","authors":"Bingyao Tan, Huakun Li, V. Barathi, L. Schmetterer, Tong Ling","doi":"10.1117/12.2672175","DOIUrl":"https://doi.org/10.1117/12.2672175","url":null,"abstract":"Recently, there has been vast interest in probing photoreceptor dynamics using optical coherence tomography (OCT). Most successful demonstrations implemented adaptive optics or digital adaptive optics to resolve individual cones or rods in human subjects. Here we use phase information to trace the photoreceptor response in rodents using an ultrahigh-resolution, phase-sensitive, spectral-domain OCT. Brown Norway rats (six to 14 weeks) were sedated using a ketamine and xylazine cocktail. Repeated scans were registered by a phase-restoring subpixel motion correction algorithm to isolate the bulk motion, and two hyperreflective bands (inner segment/outer segment junction – IS/OS; outer segment tip + retinal pigment epithelium + Bruch's membrane) were segmented automatically. As a result, two types of nanoscale signals (biphasic Type-I and monophasic Type-II) were detected with a clear separation in depth. We tested the repeatability, scotopic stimulus strength dependency, and photopic background intensity dependency. Besides, we demonstrated enface mapping of the ORG signals in a wide field of 20°, analogous to the multifocal electroretinogram but with a much higher resolution, revealing the spatial distribution of the outer retina function. This method could be extended to study animal models with photoreceptor degeneration and clinical studies to investigate early photoreceptor dysfunction with high spatiotemporal resolution.","PeriodicalId":278089,"journal":{"name":"European Conference on Biomedical Optics","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124908027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Partial Mueller polarimetry for the complete optical diagnosis of biological tissue 部分穆勒偏振法用于生物组织的完全光学诊断

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2670094

T. Novikova, J. Ramella-Roman, Leonard A. Felger, Romain Gros, E. Hewer, T. Maragkou, Richard McKinley, S. Moriconi, M. Murek, A. Pierangelo, Omar Rodríguez-Núñez, I. Zubak, P. Schucht

引用次数: 0

Morphologic analysis of the human tympanic membrane by polarization-sensitive OCT and polarized light microscopy 偏振光显微镜和偏振敏感OCT对人鼓膜的形态学分析

European Conference on Biomedical Optics Pub Date : 2023-08-11 DOI: 10.1117/12.2675002

S. Steuer, J. Morgenstern, A. Jannasch, L. Kirsten, E. Koch, Marcus Neudert, Jonas Golde

引用次数: 0