Article
Optics
Norman Lippok, Benjamin J. Vakoc
Summary: Circular-ranging optical coherence tomography (CR-OCT) systems using time-stepped frequency comb sources generate complex interference fringe signals. A mathematical framework is developed to relate the RF properties of these signals to the parameters of the frequency comb source, highlighting non-intuitive mechanisms affecting imaging performance. These findings provide a foundation for designing and optimizing time-stepped frequency comb sources and systems.
Article
Ophthalmology
Noriko Nishikawa, Jacqueline Chua, Yuriya Kawaguchi, Tomoko Ro-Mase, Leopold Schmetterer, Yasuo Yanagi, Akitoshi Yoshida
Summary: Children with unilateral amblyopia showed lower macular vessel density and thicker inner retinal layers in the amblyopic eyes compared to fellow eyes, even after correcting for image magnification, suggesting persistent differences in macular microvasculature and structural layers.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2021)
Article
Optics
Reddikumar Maddipatla, Patrice Tankam
Summary: Combining optical coherence microscopy with fluorescence microscopy allows for the alignment of structural and functional information, enabling new investigations into biological processes in animal models.
OPTICS AND LASERS IN ENGINEERING
(2022)
Article
Optics
Chenxia Xie, Wanrong Gao, Yue Zhang, Weisong Shi
Summary: In this study, a method of deriving particle density information from temporal statistics of optical coherence tomography (OCT) signals is presented. By conducting phantom experiments with high and low concentration solutions, the probability density distribution of structural information at a specific depth is obtained, and four parameters are defined to characterize the curves. Through in vivo experiments on human skin, it is found that the four parameters of the skin are not strongly related to those of the simulated solution, and the reasons for this phenomenon are analyzed. The preliminary results of this research show that the probability density distribution, which has a depth dependence, is also affected by the sample concentration.
OPTICS COMMUNICATIONS
(2023)
Article
Optics
Jianbo Tang, Xiaojun Cheng, Kivilcim Kilic, Anna Devor, Jonghwan Lee, David A. Boas
Summary: In awake mice, optical coherence tomography (OCT) imaging was used to detect localized fast optical signals (FOSs) caused by whisker stimulation. By fitting the OCT intensity signal time course with a response function, activated voxels were identified in the expected brain region for whisker stimulation, providing a new tool for neural activity studies.
Article
Biochemical Research Methods
Clayton B. Walker, Anna Wisniowiecki, Jack C. Tang, Patricia M. Quinones, Wihan Kim, John S. Oghalai, Brian E. Applegate
Summary: This paper presents a processing approach for optical coherence tomography (OCT) based on a multi-window method, which improves resolution and suppresses side-lobe intensity. By selecting appropriate window functions, the approach achieves better performance for phase-sensitive applications.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Multidisciplinary Sciences
Alina Messner, Valentin Aranha Dos Santos, Hannes Stegmann, Stefan Puchner, Doreen Schmidl, Rainer Leitgeb, Leopold Schmetterer, Rene M. Werkmeister
Summary: In this study, the use of intrinsic optical signals as a noninvasive biomarker for assessing retinal photoreceptor function was explored. Results showed dynamic changes in optical path length between different anatomical structures in the outer retina during light stimulation, suggesting the potential for using a standard OCT platform and signal model in measuring subretinal changes in response to light adaptation.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2022)
Article
Optics
Wenxin Zhang, Zhengyu Chen, Xiao Zhang, Chengming Wang, Bin He, Ning Liu, Yangkang Wu, Yuxiu Tao, Ning Zhang, Ping Xue
Summary: In this paper, we propose a novel technique to measure fiber dispersion without the need for any derivative operation or index measurement. By utilizing the relationship between dispersion and the signal in optical computing optical coherence tomography, dispersion can be accurately deduced from the position and resolution of the optical computing OCT signal. The measured group velocity dispersion and third order dispersion of single mode fiber and dispersion compensating fiber with lengths ranging from 10 m to 10 km are found to be in good agreement with the nominal value.
Article
Multidisciplinary Sciences
Valentin Hacker, Gregor Sebastian Reiter, Markus Schranz, Reinhard Told, Adrian Reumueller, Dominik Hofer, Irene Steiner, Ursula Schmidt-Erfurth, Stefan Sacu
Summary: This study found that large choroidal vessels (LCV) have a significant impact on the Choriocapillaris (CC) flow deficit (FD) analyses of swept-source optical coherence tomography angiography (SS-OCTA) images, with their visibility negatively associated with choroidal thickness (CT). In patients with intermediate age-related macular degeneration, areas containing LCV showed significantly lower FD%.
Article
Optics
Jianan Fang, Kun Huang, E. Wu, Ming Yan, Heping Zeng
Summary: This article introduces an infrared 3D imaging system capable of detecting three-dimensional structure and reflectivity information. The system operates at single-photon sensitivity and femtosecond timing resolution, enabling imaging under low-light conditions. By nonlinear frequency upconversion and recording with a silicon camera, the presented system achieves high lateral and depth resolutions for 3D reconstruction. Additionally, a numerical denoiser based on spatiotemporal correlation allows the retrieval of object profile and reflectivity even with a detected flux below 0.05 photons/pixel/second. This infrared 3D imager features high detection sensitivity, precise timing resolution, and wide-field operation, offering new possibilities in life and material sciences.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Multidisciplinary Sciences
Woo-Hyuk Lee, Yong-Jin Na, Hyung-Bin Lim, Jae-Yun Sung, Jung-Yeul Kim, Min-Woo Lee
Summary: This study aimed to investigate the changes in the inner retinal layer and microvasculature in healthy eyes with age. The results showed that the ganglion cell-inner plexiform layer (GC-IPL) thickness and macular vessel density (VD) started to decrease in the age group above 50 years, while the GC-IPL/VD ratio significantly increased in the 60s age group. Furthermore, the GC-IPL/VD ratio was positively associated with age in subjects aged 50 years and above, indicating a more pronounced decline in VD over time compared to GC-IPL thickness.
Article
Optics
Kentaro Saeki, Decai Huyan, Mio Sawada, Akira Nakamura, Shin Kubota, Kenji Uno, Kazuhiko Ohnuma, Tatsuo Shiina
Summary: A study was conducted on measuring special shaped contact lenses using a time-domain optical coherence tomography device. An algorithm combined with sphere fitting was proposed for shape, thickness, and curvature radius estimation. The accuracy was verified using simulated data, and evaluation of a toric-shaped mold was done by comparing coordinates and intensity of interference signals.
Article
Pharmacology & Pharmacy
Thibaud Mathis, Batoul El Ameen, Cristina Vartin, Yasmine Serrar, Frederic Matonti, Aditya Sudhalkar, Alper Bilgic, Amina Rezkallah, Laurent Kodjikian
Summary: This study examined the validity of using anatomical criteria alone to make retreatment decisions in patients with DME, compared to the gold standard that incorporates visual acuity. The OCT-guided strategy yielded equivalent results to the gold standard in 82.7% of cases, with variations in sensitivity and specificity based on the patient's treatment regimen.
Article
Materials Science, Characterization & Testing
Pinbo Huang, Shengli Xie, Zhanxi Cao, Zihao Ni, Bo Dong, Yulei Bai
Summary: This study proposes a method for measuring the strain field of PMMA sheets using phase-contrast optical coherence tomography. The results show that the strain fields of PMMA sheets are non-uniform, with stress concentration occurring at defects, and the Poisson's ratio of PMMA is 0.35-0.37.
Article
Optics
Zunyue Zhang, Yi Wang, Jiarui Wang, Dan Yi, David Weng U. Chan, Wu Yuan, Hon Ki Tsang
Summary: In this study, a compact integrated scanning spectrometer is proposed, which utilizes a tunable micro-ring resonator and a single arrayed waveguide grating to achieve wide optical bandwidths and high spectral resolutions. The integrated spectrometer with germanium photodetectors demonstrates excellent performance.
PHOTONICS RESEARCH
(2022)
Article
Ophthalmology
Grace M. Richter, Jae Chang Lee, Nasir Khan, Alexander Vorperian, Brennan Hand, Bruce Burkemper, Xiao Zhou, Zhongdi Chu, Ruikang Wang, Rohit Varma, Amir H. Kashani
Summary: This study aimed to investigate the relationship between systemic and ocular characteristics and perifoveal and macular vessel density in healthy African American eyes. The results showed that longer axial length, reduced signal strength, reduced central subfield thickness, and older age were independently associated with reduced perifoveal and macular vessel density.
BRITISH JOURNAL OF OPHTHALMOLOGY
(2023)
Article
Computer Science, Interdisciplinary Applications
Alireza Karimi, Reza Razaghi, Seyed Mohammadali Rahmati, J. Crawford Downs, Ted S. Acott, Ruikang K. Wang, Murray Johnstone
Summary: Intraocular pressure is determined by the resistance of aqueous humor outflow, which is influenced by the mechanical properties of trabecular meshwork, Schlemm's canal inner wall, and juxtacanalicular connective tissue. Understanding the biomechanical interactions of aqueous humor with outflow tissues is crucial for regulating outflow resistance and fluid dynamics in the eye.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2022)
Article
Computer Science, Interdisciplinary Applications
Alireza Karimi, Seyed Mohammadali Rahmati, Reza Razaghi, J. Crawford Downs, Ted S. Acott, Ruikang K. Wang, Murray Johnstone
Summary: The stiffness of the trabecular meshwork is significantly higher in glaucoma eyes compared to healthy eyes, indicating differences in viscoelastic mechanical behavior. These findings shed light on the mechanical property distinctions in the outflow pathway of healthy and glaucomatous eyes under dynamic loading, potentially serving as a new biomarker for early diagnosis of glaucoma.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2022)
Article
Ophthalmology
Alexander Vorperian, Nasir Khan, Jae Lee, Bruce Burkemper, Xiao Zhou, Dominic Grisafe, Vivian LeTran, Zhongdi Chu, Brandon Wong, Benjamin Xu, Brian Song, Ruikang K. Wang, Grace Richter
Summary: This study compared the intrasession repeatability and intersession reproducibility of macular vessel parameters in glaucoma and non-glaucoma subjects using optical coherence tomography angiography (OCTA). The results showed that macular OCTA scans have high repeatability and reproducibility, making them a useful tool in monitoring the longitudinal progression of glaucoma.
CURRENT EYE RESEARCH
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Woo June Choi, Yuandong Li, Ruikang K. Wang, Jun Ki Kim
Summary: This paper proposes a method using OCT for counting penetrating blood vessels, which can effectively identify and count cortical penetrating vessels with an accuracy of over 87%. The study also observed a significant reduction in penetrating vessel density in a mouse model of focal ischemic stroke.
Article
Optics
Qinghua He, Ruikang K. Wang
Summary: We present a method for imaging facial cutaneous microvascular perfusion using wide-field imaging photoplethysmography (iPPG) and handheld swept-source optical coherence tomography (OCT). The iPPG system utilizes a 16-bit-depth camera to generate a 2D wide-field blood pulsation map for guiding the OCT imaging of cutaneous microvasculature. The results from iPPG and OCT demonstrate the potential of guided imaging of cutaneous microvasculature for assessing skin conditions in dermatology and cosmetology.
Article
Ophthalmology
Paul. S. Micevych, Jessica Wong, Hao Zhou, Ruikan. K. Wang, Travis. C. Porco, Joseph Carroll, Austin Roorda, Jacque. L. Duncan
Summary: This study compared cone structure and function between patients with RPGR and USH2A-related retinal degeneration. It found that outer retinal structure and choriocapillaris perfusion were more abnormal in patients with RPGR-related retinal degeneration compared to those with USH2A-related retinal degeneration. However, there were no significant differences in below-normal regional sensitivity between rod-cone degeneration associated with variants in these 2 genes expressed at the photoreceptor-connecting cilium.
AMERICAN JOURNAL OF OPHTHALMOLOGY
(2023)
Article
Clinical Neurology
Wenbin Zhu, Catherine M. M. Davis, Elyse M. M. Allen, Sarah L. L. Feller, Thierno M. M. Bah, Robert E. E. Shangraw, Ruikang K. K. Wang, Nabil J. J. Alkayed
Summary: In this study, the researchers found that poor outcome after stroke in patients with type 2 diabetes (DM2) is linked to impaired microvascular tissue reperfusion. Furthermore, they discovered differences in microvascular reperfusion response between male and female DM2 mice after transient middle cerebral artery occlusion (MCAO). These findings suggest that DM2 impairs capillary perfusion and exacerbates ischemic brain injury in male but not female mice with DM2.
Editorial Material
Biochemical Research Methods
Ruikang K. Wang, Sina Farsiu
Summary: The Editor-in-Chief and Deputy Editor of Biomedical Optics Express have introduced a new prize to honor the best paper published in the Journal between 2019 and 2021.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Biochemical Research Methods
Qinghua He, Wanyu Li, Yaping Shi, Yi Yu, Wenqian Geng, Zhiyuan Sun, Ruikang K. Wang
Summary: SpeCamX is a mobile application that transforms a regular smartphone into a multispectral imager. It utilizes the smartphone's RGB photographs and converts them into multispectral images, eliminating the need for specialized devices or attachments. The app also includes plugin functions for extracting medical information. In a clinical study, SpeCamX was used to create an augmented smartphone bilirubinometer with superior performance compared to default smartphone cameras.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Biochemical Research Methods
Philip J. Rosenfeld, Yuxuan Cheng, Mengxi Shen, Giovanni Gregori, Ruikang K. Wang
Summary: The use of optical attenuation coefficients in OCT imaging has improved the segmentation of anatomical layers and allows for better measurement of choroidal indicators. It also enables the detection of factors associated with disease progression.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Biochemical Research Methods
Qinghua He, Wenqian Geng, Wanyu Li, Ruikang k. Wang
Summary: This study presents a method and system for non-contact measurement of neck pulses using micro-motion imaging (mu MI). The proposed method extracts carotid pulse (CP) and jugular vein pulse (JVP) waveforms without the need for manual identification, making it non-invasive and self-guided. The experimental results demonstrate the feasibility of the method and its potential use in early screening of cardiovascular diseases.
BIOMEDICAL OPTICS EXPRESS
(2023)
Meeting Abstract
Endocrinology & Metabolism
I. Hirsch, M. Shinohara, A. Kalus, R. Wang, J. Lu, J. Baran, D. Khakpour
DIABETES TECHNOLOGY & THERAPEUTICS
(2022)
Article
Ophthalmology
Sam Kushner-Lenhoff, Yuandong Li, Qinqin Zhang, Ruikang K. Wang, Xuejuan Jiang, Amir H. Kashani
Summary: This study examines the relationship between retinal capillary flux measured by optical coherence tomography angiography (OCTA) and systemic determinants of health. The results suggest that retinal capillary perfusion, as indicated by flux and vessel skeleton density (VSD), is associated with various systemic factors, such as age, blood pressure, diabetes status, and hematocrit. The findings highlight the potential of OCTA-derived measures to provide additional information about retinal perfusion and its relationship with overall health.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Meeting Abstract
Medicine, General & Internal
S. Lee, R. K. Wang
JOURNAL OF INVESTIGATIVE MEDICINE
(2022)
