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Wei W, Anantharanjit R, Patel RP, Cordeiro MF. Detection of macular atrophy in age-related macular degeneration aided by artificial intelligence. Expert Rev Mol Diagn 2023:1-10. [PMID: 37144908 DOI: 10.1080/14737159.2023.2208751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
INTRODUCTION Age-related macular degeneration (AMD) is a leading cause of irreversible visual impairment worldwide. The endpoint of AMD, both in its dry or wet form, is macular atrophy (MA) which is characterized by the permanent loss of the RPE and overlying photoreceptors either in dry AMD or in wet AMD. A recognized unmet need in AMD is the early detection of MA development. AREAS COVERED Artificial Intelligence (AI) has demonstrated great impact in detection of retinal diseases, especially with its robust ability to analyze big data afforded by ophthalmic imaging modalities, such as color fundus photography (CFP), fundus autofluorescence (FAF), near-infrared reflectance (NIR), and optical coherence tomography (OCT). Among these, OCT has been shown to have great promise in identifying early MA using the new criteria in 2018. EXPERT OPINION There are few studies in which AI-OCT methods have been used to identify MA; however, results are very promising when compared to other imaging modalities. In this paper, we review the development and advances of ophthalmic imaging modalities and their combination with AI technology to detect MA in AMD. In addition, we emphasize the application of AI-OCT as an objective, cost-effective tool for the early detection and monitoring of the progression of MA in AMD.
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Affiliation(s)
- Wei Wei
- Department of Ophthalmology, Ningbo Medical Center Lihuili Hospital, Ningbo, China
- Department of Surgery & Cancer, Imperial College London, London, UK
- Imperial College Ophthalmology Research Group (ICORG), Imperial College Ophthalmology Research Group, London, UK
| | - Rajeevan Anantharanjit
- Imperial College Ophthalmology Research Group (ICORG), Imperial College Ophthalmology Research Group, London, UK
- Western Eye Hospital, Imperial College Healthcare NHS trust, London, UK
| | - Radhika Pooja Patel
- Imperial College Ophthalmology Research Group (ICORG), Imperial College Ophthalmology Research Group, London, UK
- Western Eye Hospital, Imperial College Healthcare NHS trust, London, UK
| | - Maria Francesca Cordeiro
- Department of Surgery & Cancer, Imperial College London, London, UK
- Imperial College Ophthalmology Research Group (ICORG), Imperial College Ophthalmology Research Group, London, UK
- Western Eye Hospital, Imperial College Healthcare NHS trust, London, UK
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Rahman MH, Jeong HW, Kim NR, Kim DY. Automatic Quantification of Anterior Lamina Cribrosa Structures in Optical Coherence Tomography Using a Two-Stage CNN Framework. SENSORS (BASEL, SWITZERLAND) 2021; 21:5383. [PMID: 34450823 PMCID: PMC8400634 DOI: 10.3390/s21165383] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 07/28/2021] [Accepted: 08/03/2021] [Indexed: 11/17/2022]
Abstract
In this study, we propose a new intelligent system to automatically quantify the morphological parameters of the lamina cribrosa (LC) of the optical coherence tomography (OCT), including depth, curve depth, and curve index from OCT images. The proposed system consisted of a two-stage deep learning (DL) model, which was composed of the detection and the segmentation models as well as a quantification process with a post-processing scheme. The models were used to solve the class imbalance problem and obtain Bruch's membrane opening (BMO) as well as anterior LC information. The detection model was implemented by using YOLOv3 to acquire the BMO and LC position information. The Attention U-Net segmentation model is used to compute accurate locations of the BMO and LC curve information. In addition, post-processing is applied using polynomial regression to attain the anterior LC curve boundary information. Finally, the numerical values of morphological parameters are quantified from BMO and LC curve information using an image processing algorithm. The average precision values in the detection performances of BMO and LC information were 99.92% and 99.18%, respectively, which is very accurate. A highly correlated performance of R2 = 0.96 between the predicted and ground-truth values was obtained, which was very close to 1 and satisfied the quantification results. The proposed system was performed accurately by fully automatic quantification of BMO and LC morphological parameters using a DL model.
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Affiliation(s)
- Md Habibur Rahman
- Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea; (M.H.R.); (H.W.J.)
| | - Hyeon Woo Jeong
- Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea; (M.H.R.); (H.W.J.)
| | - Na Rae Kim
- Department of Ophthalmology, Inha University, Incheon 22212, Korea
| | - Dae Yu Kim
- Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Korea; (M.H.R.); (H.W.J.)
- Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea
- Center for Sensor Systems, Inha University, Incheon 22212, Korea
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Meemon P, Lenaphet Y, Widjaja J. Spectral fusing Gabor domain optical coherence microscopy based on FPGA processing. APPLIED OPTICS 2021; 60:2069-2076. [PMID: 33690300 DOI: 10.1364/ao.415270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
High-resolution imaging using high numerical aperture imaging optics is commonly known to cause a narrow depth of focus, which limits the depth of field in optical coherence tomography (OCT). To achieve semi-invariant high resolution in all directions, Gabor domain optical coherence microscopy (GD-OCM) combines the in-focus regions of multiple cross-sectional images that are acquired while shifting the focal plane of the objective lens. As a result, GD-OCM requires additional processes for in-focus extraction and fusion, leading to longer processing times, as compared with conventional frequency domain OCT (FD-OCT). We previously proposed a method of spectral domain Gabor fusion that has been proven to improve the processing speed of GD-OCM. To investigate the full potential of the spectral domain Gabor fusion technique, we present the implementation of the spectral domain Gabor fusion algorithm using field programmable gate arrays (FPGAs) in a spectral acquisition hardware device. All filtering processes are now performed in an acquisition device as opposed to the post-processing of the original GD-OCM, which reduces the amount of data transfer between the image acquisition device and the processing host. To clearly demonstrate the imaging performance of the implemented system, we performed GD-OCM imaging of a stack of polymeric tapes. GD-OCM imaging was performed over seven focus zones. The results showed that the processing time for linear wavenumber calibration and spectral Gabor filtering can be improved with FPGA implementation. The total processing time was improved by about 35%.
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Jeon B, Lee J, Jeon D, Kim P, Jang JH, Wijesinghe RE, Jeon M, Kim J. Functional assessment of moisture influenced cadaveric tympanic membrane using phase shift-resolved optical Doppler vibrography. JOURNAL OF BIOPHOTONICS 2020; 13:e201900202. [PMID: 31670908 DOI: 10.1002/jbio.201900202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 10/16/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
An elevated relative moisture in the external ear canal and middle ear cavity may predispose to chronic otorrhea and related infections along with abnormal tympanic membrane (TM) vibration patterns. Therefore, phase shift-resolved optical Doppler vibrography (ODV) was used for vibration assessments of moisture influenced cadaveric TM. ODV was applied to generate time resolved cross-sectional and volumetric vibrographs of a cadaveric TM, driven acoustically at several frequencies. In order to analyze the effect of moisture on TM, homogenous moisture conditions were provided by soaking the cadaveric TM specimens in 1× phosphate buffer saline with a pH of 7.4. The TM specimen was exposed to a rapidly switchable frequency generator during the ODV image acquisition. The experiment was conducted for 3 hours and the cadaveric TM was exposed to each frequency with an interval of 30 minutes. Acquired phase shift-resolved ODV assessments revealed a depth dependent vibration tendency between the applied frequencies, along with a decline in the moisture level of the cadaveric TM specimen. Thus, the ODV method can aid our understanding of sound conduction in the middle ear, thus supporting the diagnosis of TM diseases.
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Affiliation(s)
- Byeonggyu Jeon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Jaeyul Lee
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Deokmin Jeon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Pilun Kim
- Institute of Biomedical Engineering, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Jeong Hun Jang
- Department of Otolaryngology, School of Medicine, Ajou University, Gyeongsan, Republic of Korea
| | - Ruchire Eranga Wijesinghe
- Department of Biomedical Engineering, College of Engineering, Kyungil University, Gyeongsan, Republic of Korea
| | - Mansik Jeon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Jeehyun Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Republic of Korea
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Lee HJ, Samiudin NM, Lee TG, Doh I, Lee SW. Retina phantom for the evaluation of optical coherence tomography angiography based on microfluidic channels. BIOMEDICAL OPTICS EXPRESS 2019; 10:5535-5548. [PMID: 31799029 PMCID: PMC6865089 DOI: 10.1364/boe.10.005535] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/28/2019] [Accepted: 09/28/2019] [Indexed: 05/22/2023]
Abstract
Optical coherence tomography (OCT) angiography (OCTA) has been actively studied as a noninvasive imaging technology to generate retinal blood vessel network maps for the diagnoses of retinal diseases. Given that the uses of OCT and OCTA have increased in the field of ophthalmology, it is necessary to develop retinal phantoms for clinical OCT for product development, performance evaluation, calibration, certification, medical device licensing, and production processes. We developed a retinal layer-mimicking phantom with microfluidic channels based on microfluidic fabrication technology using polydimethylsiloxane (PDMS) and titanium dioxide (TiO2) powder. We implemented superficial and deep retinal vessels using microfluidic channels. In addition, multilayered thin films were synthesized with multiple spin-coating processes that comprised layers that corresponded to the retinal layers, including the ganglion cell layer (GCL), inner plexiform layer (IPL), and inner nuclear layer (INL). The phantom was formed by merging the multilayered thin film, and microfluidic channels were assembled with an optical lens, water chamber, and an aluminum tube case. Finally, we obtained cross-sectional OCT images and en-face OCTA images of the retinal phantom using lab-made ophthalmic OCT. From the cross-sectional OCT image, we could compare each of the layer thicknesses of the phantom with the corresponding layer thicknesses of the human retina. In addition, we obtained en-face OCTA images with injections of intralipid solutions. It is shown that this phantom will be able to be potentially used as a convenient tool to evaluate and standardize the quality and accuracy of OCT and OCTA images.
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Affiliation(s)
- Hyun-Ji Lee
- Center for Nano-Bio Measurement, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
- Department of Medical Physics, Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
| | - Nafra M Samiudin
- Center for Medical Convergence Metrology, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
- Department of Medical Physics, Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
| | - Tae Geol Lee
- Center for Nano-Bio Measurement, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
- Department of Nano Science, Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
| | - Il Doh
- Center for Medical Convergence Metrology, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
- Department of Medical Physics, Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
| | - Sang-Won Lee
- Center for Nano-Bio Measurement, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
- Department of Medical Physics, Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, South Korea
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Measurement of Vibrating Tympanic Membrane in an In Vivo Mouse Model Using Doppler Optical Coherence Tomography. J Imaging 2019; 5:jimaging5090074. [PMID: 34460668 PMCID: PMC8320936 DOI: 10.3390/jimaging5090074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/30/2019] [Accepted: 09/01/2019] [Indexed: 11/17/2022] Open
Abstract
Optical coherence tomography (OCT) has a micro-resolution with a penetration depth of about 2 mm and field of view of about 10 mm. This makes OCT well suited for analyzing the anatomical and internal structural assessment of the middle ear. To study the vibratory motion of the tympanic membrane (TM) and its internal structure, we developed a phase-resolved Doppler OCT system using Kasai’s autocorrelation algorithm. Doppler optical coherence tomography is a powerful imaging tool which can offer the micro-vibratory measurement of the tympanic membrane and obtain the micrometer-resolved cross-sectional images of the sample in real-time. To observe the relative vibratory motion of individual sections (malleus, thick regions, and the thin regions of the tympanic membrane) of the tympanic membrane in respect to auditory signals, we designed an experimental study for measuring the difference in Doppler phase shift for frequencies varying from 1 to 8 kHz which were given as external stimuli to the middle ear of a small animal model. Malleus is the very first interconnecting region between the TM and cochlea. In our proposed study, we observed that the maximum change in Doppler phase shift was seen for the 4 kHz acoustic stimulus in the malleus, the thick regions, and in the thin regions of the tympanic membrane. In particular, the vibration signals were higher in the malleus in comparison to the tympanic membrane.
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Non-Invasive Morphological Characterization of Rice Leaf Bulliform and Aerenchyma Cellular Regions Using Low Coherence Interferometry. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9102104] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Non-invasive investigation of rice leaf specimens to characterize the morphological formation and particular structural information that is beneficial for agricultural perspective was demonstrated using a low coherence interferometric method called swept source optical coherence tomography (SS-OCT). The acquired results non-invasively revealed morphological properties of rice leaf, such as bulliform cells; aerenchyma, parenchyma, and collenchyma layer; and vascular bundle. Beside aforementioned morphologic characteristics, several leaf characteristics associated with cytological mechanisms of leaf rolling (leaf inclination) were examined for the pre-identification of inevitable necrosis and atrophy of leaf tissues by evaluating acute angle information, such as angular characteristics of the external bi-directional angles between the lower epidermis layer and lower mid-vein, and internal angle of lower mid-vein. To further assist the pre-identification, acquired cross-sections were employed to enumerate the small veins of each leaf specimen. Since mutants enlarge leaf angles due to increased cell division in the adaxial epidermis, healthy and abnormal leaf specimens were morphologically and quantitatively compared. Therefore, the results of the method can be used in agriculture, and SS-OCT shows potential as a rigorous investigation method for selecting mutant infected rice leaf specimens rapidly and non-destructively compared to destructive and time consuming gold-standard methods with a lack of precision.
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Jeon D, Cho NH, Park K, Kim K, Jeon M, Jang JH, Kim J. In Vivo Vibration Measurement of Middle Ear Structure Using Doppler Optical Coherence Tomography: Preliminary Study. Clin Exp Otorhinolaryngol 2018; 12:40-49. [PMID: 30045616 PMCID: PMC6315208 DOI: 10.21053/ceo.2018.00185] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 05/31/2018] [Indexed: 12/27/2022] Open
Abstract
Objectives Doppler optical coherence tomography (DOCT) is useful for both, the spatially resolved measurement of the tympanic membrane (TM) oscillation and high-resolution imaging. We demonstrated a new technique capable of providing real-time two-dimensional Doppler OCT image of rapidly oscillatory latex mini-drum and in vivo rat TM and ossicles. Methods Using DOCT system, the oscillation of sample was measured at frequency range of 1–4 kHz at an output of 15 W. After the sensitivity of the DOCT system was verified using a latex mini-drum consisting of a 100 μm-thick latex membrane, changes in displacement of the umbo and contacted area between TM and malleus in normal and pathologic conditions. Results The oscillation cycles of the mini-drum for stimulus frequencies were 1.006 kHz for 1 kHz, 2.012 kHz for 2kHz, and 3.912 kHz for 4 kHz, which means that the oscillation cycle of the mini-drum become short in proportional to the frequency of stimuli. The oscillation cycles of umbo area and the junction area in normal TM for frequencies of the stimuli showed similar integer ratio with the data of latex mini-drum for stimuli less than 4 kHz. In the case of middle ear effusion condition, the Doppler signal showed a tendency of attenuation in all frequencies, which was prominent at 1 kHz and 2 kHz. Conclusion The TM vibration under sound stimulation with frequencies from 1 kHz to 4 kHz in normal and pathologic conditions was demonstrated using signal demodulation method in in vivo condition. The OCT technology could be helpful for functional and structural assessment as an optional modality.
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Affiliation(s)
- Doekmin Jeon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Korea
| | - Nam Hyun Cho
- Department of Otology and Laryngology, Harvard Medical School, Boston, MA, USA.,Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary (MEEI), Boston, MA, USA
| | - Kibeom Park
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Korea
| | - Kanghae Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Korea
| | - Mansik Jeon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Korea
| | - Jeong Hun Jang
- Department of Otolaryngology, Ajou University School of Medicine, Suwon, Korea
| | - Jeehyun Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu, Korea
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Structural Analysis of Polymer Composites Using Spectral Domain Optical Coherence Tomography. SENSORS 2017; 17:s17051155. [PMID: 28524105 PMCID: PMC5470901 DOI: 10.3390/s17051155] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/23/2017] [Accepted: 05/15/2017] [Indexed: 11/24/2022]
Abstract
The structural analysis of nylon/graphene oxide (NY/GO) and polyetherblockamide/ trisilinolphenyl-polyhederal oligomeric silsesquioxane (PEBA/t-POSS) composites were performed using high-resolution spectral domain optical coherence tomography (SD-OCT). This optical technology revealed both cross-sectional, as well as sub-layer depth information of sample. The non-destructive real-time imaging demonstrated the nature of defects in the composites. The thickness and location of each defect point in the composites were measured using A-scan analysis on the SD-OCT images. The cross-sectional and volumetric images clearly demonstrate the effectiveness of SD-OCT for composite research, as well as the for industrial quality assurance of polymer materials.
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In Vivo Near Infrared Virtual Intraoperative Surgical Photoacoustic Optical Coherence Tomography. Sci Rep 2016; 6:35176. [PMID: 27731390 PMCID: PMC5059626 DOI: 10.1038/srep35176] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/26/2016] [Indexed: 01/06/2023] Open
Abstract
Since its first implementation in otolaryngological surgery nearly a century ago, the surgical microscope has improved the accuracy and the safety of microsurgeries. However, the microscope shows only a magnified surface view of the surgical region. To overcome this limitation, either optical coherence tomography (OCT) or photoacoustic microscopy (PAM) has been independently combined with conventional surgical microscope. Herein, we present a near-infrared virtual intraoperative photoacoustic optical coherence tomography (NIR-VISPAOCT) system that combines both PAM and OCT with a conventional surgical microscope. Using optical scattering and absorption, the NIR-VISPAOCT system simultaneously provides surgeons with real-time comprehensive biological information such as tumor margins, tissue structure, and a magnified view of the region of interest. Moreover, by utilizing a miniaturized beam projector, it can back-project 2D cross-sectional PAM and OCT images onto the microscopic view plane. In this way, both microscopic and cross-sectional PAM and OCT images are concurrently displayed on the ocular lens of the microscope. To verify the usability of the NIR-VISPAOCT system, we demonstrate simulated surgeries, including in vivo image-guided melanoma resection surgery and in vivo needle injection of carbon particles into a mouse thigh. The proposed NIR-VISPAOCT system has potential applications in neurosurgery, ophthalmological surgery, and other microsurgeries.
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Kim S, Lee C, Kim JY, Kim J, Lim G, Kim C. Two-axis polydimethylsiloxane-based electromagnetic microelectromechanical system scanning mirror for optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:106001. [PMID: 27731491 DOI: 10.1117/1.jbo.21.10.106001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/19/2016] [Indexed: 06/06/2023]
Abstract
Compact size and fast imaging abilities are key requirements for the clinical implementation of an optical coherence tomography (OCT) system. Among the various small-sized technology, a microelectromechanical system (MEMS) scanning mirror is widely used in a miniaturized OCT system. However, the complexities of conventional MEMS fabrication processes and relatively high costs have restricted fast clinical translation and commercialization of the OCT systems. To resolve these problems, we developed a two-axis polydimethylsiloxane (PDMS)-based MEMS (2A-PDMS-MEMS) scanning mirror through simple processes with low costs. It had a small size of 15×15×15??mm3, was fast, and had a wide scanning range at a low voltage. The AC/DC responses were measured to evaluate the performance of the 2A-PDMS-MEMS scanning mirror. The maximum scanning angles were measured as ±16.6??deg and ±11.6??deg along the X and Y axes, respectively, and the corresponding field of view was 29.8??mm×20.5??mm with an optical focal length of 50 mm. The resonance frequencies were 82 and 57 Hz along the X and Y axes, respectively. Finally, in vivo B-scan and volumetric OCT images of human fingertips and palms were successfully acquired using the developed SD-OCT system based on the 2A-PDMS-MEMS scanning mirror.
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Affiliation(s)
- Sehui Kim
- Pohang University of Science and Technology (POSTECH), Department of Creative IT Engineering, 77 Cheongam-ro, Pohang, Republic of Korea
| | - Changho Lee
- Pohang University of Science and Technology (POSTECH), Department of Creative IT Engineering, 77 Cheongam-ro, Pohang, Republic of Korea
| | - Jin Young Kim
- Pohang University of Science and Technology (POSTECH), Department of Creative IT Engineering, 77 Cheongam-ro, Pohang, Republic of Korea
| | - Jeehyun Kim
- Kyungpook National University, School of Electrical Engineering, 80 Daehak-ro, Daegu, Republic of Korea
| | - Geunbae Lim
- Pohang University of Science and Technology (POSTECH), Department of Mechanical Engineering, 77 Cheongam-ro, Pohang, Republic of Korea
| | - Chulhong Kim
- Pohang University of Science and Technology (POSTECH), Department of Creative IT Engineering, 77 Cheongam-ro, Pohang, Republic of Korea
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Fast Industrial Inspection of Optical Thin Film Using Optical Coherence Tomography. SENSORS 2016; 16:s16101598. [PMID: 27690043 PMCID: PMC5087387 DOI: 10.3390/s16101598] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/19/2016] [Accepted: 09/22/2016] [Indexed: 11/16/2022]
Abstract
An application of spectral domain optical coherence tomography (SD-OCT) was demonstrated for a fast industrial inspection of an optical thin film panel. An optical thin film sample similar to a liquid crystal display (LCD) panel was examined. Two identical SD-OCT systems were utilized for parallel scanning of a complete sample in half time. Dual OCT inspection heads were utilized for transverse (fast) scanning, while a stable linear motorized translational stage was used for lateral (slow) scanning. The cross-sectional and volumetric images of an optical thin film sample were acquired to detect the defects in glass and other layers that are difficult to observe using visual inspection methods. The rapid inspection enabled by this setup led to the early detection of product defects on the manufacturing line, resulting in a significant improvement in the quality assurance of industrial products.
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Lee C, Lee D, Zhou Q, Kim J, Kim C. Real-time Near-infrared Virtual Intraoperative Surgical Photoacoustic Microscopy. PHOTOACOUSTICS 2015; 3:100-106. [PMID: 26640772 PMCID: PMC4595515 DOI: 10.1016/j.pacs.2015.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/16/2015] [Accepted: 08/07/2015] [Indexed: 05/29/2023]
Abstract
We developed a near infrared (NIR) virtual intraoperative surgical photoacoustic microscopy (NIR-VISPAM) system that combines a conventional surgical microscope and an NIR light photoacoustic microscopy (PAM) system. NIR-VISPAM can simultaneously visualize PA B-scan images at a maximum display rate of 45 Hz and display enlarged microscopic images on a surgeon's view plane through the ocular lenses of the surgical microscope as augmented reality. The use of the invisible NIR light eliminated the disturbance to the surgeon's vision caused by the visible PAM excitation laser in a previous report. Further, the maximum permissible laser pulse energy at this wavelength is approximately 5 times more than that at the visible spectral range. The use of a needle-type ultrasound transducer without any water bath for acoustic coupling can enhance convenience in an intraoperative environment. We successfully guided needle and injected carbon particles in biological tissues ex vivo and in melanoma-bearing mice in vivo.
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Affiliation(s)
- Changho Lee
- Research Center for Advanced Robotic Surgery based on Deep Tissue Imaging and Haptic Feedback Technology, Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, Republic of Korea
- Future IT Innovation Laboratory, Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, Republic of Korea
| | - Donghyun Lee
- Future IT Innovation Laboratory, Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, Republic of Korea
| | - Qifa Zhou
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90033, USA
| | - Jeehyun Kim
- School of Electrical Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Chulhong Kim
- Research Center for Advanced Robotic Surgery based on Deep Tissue Imaging and Haptic Feedback Technology, Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, Republic of Korea
- Future IT Innovation Laboratory, Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, Republic of Korea
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Wieser W, Draxinger W, Klein T, Karpf S, Pfeiffer T, Huber R. High definition live 3D-OCT in vivo: design and evaluation of a 4D OCT engine with 1 GVoxel/s. BIOMEDICAL OPTICS EXPRESS 2014; 5:2963-77. [PMID: 25401010 PMCID: PMC4230855 DOI: 10.1364/boe.5.002963] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 06/24/2014] [Accepted: 06/25/2014] [Indexed: 05/18/2023]
Abstract
We present a 1300 nm OCT system for volumetric real-time live OCT acquisition and visualization at 1 billion volume elements per second. All technological challenges and problems associated with such high scanning speed are discussed in detail as well as the solutions. In one configuration, the system acquires, processes and visualizes 26 volumes per second where each volume consists of 320 x 320 depth scans and each depth scan has 400 usable pixels. This is the fastest real-time OCT to date in terms of voxel rate. A 51 Hz volume rate is realized with half the frame number. In both configurations the speed can be sustained indefinitely. The OCT system uses a 1310 nm Fourier domain mode locked (FDML) laser operated at 3.2 MHz sweep rate. Data acquisition is performed with two dedicated digitizer cards, each running at 2.5 GS/s, hosted in a single desktop computer. Live real-time data processing and visualization are realized with custom developed software on an NVidia GTX 690 dual graphics processing unit (GPU) card. To evaluate potential future applications of such a system, we present volumetric videos captured at 26 and 51 Hz of planktonic crustaceans and skin.
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Affiliation(s)
- Wolfgang Wieser
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
| | - Wolfgang Draxinger
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
| | - Thomas Klein
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
| | - Sebastian Karpf
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
| | - Tom Pfeiffer
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
| | - Robert Huber
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck Germany
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15
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Tankam P, Santhanam AP, Lee KS, Won J, Canavesi C, Rolland JP. Parallelized multi-graphics processing unit framework for high-speed Gabor-domain optical coherence microscopy. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:71410. [PMID: 24695868 PMCID: PMC4019421 DOI: 10.1117/1.jbo.19.7.071410] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 02/27/2014] [Accepted: 03/07/2014] [Indexed: 05/20/2023]
Abstract
Gabor-domain optical coherence microscopy (GD-OCM) is a volumetric high-resolution technique capable of acquiring three-dimensional (3-D) skin images with histological resolution. Real-time image processing is needed to enable GD-OCM imaging in a clinical setting. We present a parallelized and scalable multi-graphics processing unit (GPU) computing framework for real-time GD-OCM image processing. A parallelized control mechanism was developed to individually assign computation tasks to each of the GPUs. For each GPU, the optimal number of amplitude-scans (A-scans) to be processed in parallel was selected to maximize GPU memory usage and core throughput. We investigated five computing architectures for computational speed-up in processing 1000×1000 A-scans. The proposed parallelized multi-GPU computing framework enables processing at a computational speed faster than the GD-OCM image acquisition, thereby facilitating high-speed GD-OCM imaging in a clinical setting. Using two parallelized GPUs, the image processing of a 1×1×0.6 mm3 skin sample was performed in about 13 s, and the performance was benchmarked at 6.5 s with four GPUs. This work thus demonstrates that 3-D GD-OCM data may be displayed in real-time to the examiner using parallelized GPU processing.
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Affiliation(s)
- Patrice Tankam
- University of Rochester, The Institute of Optics, 275 Hutchinson Road, Rochester, New York 14627
- University of Rochester, Center for Visual Science, 601 Elmwood Avenue, Rochester, New York 14642
| | - Anand P. Santhanam
- University of California, Department of Radiation Oncology, Los Angeles, 200 Medical plaza drive, Los Angeles, California 90095
| | - Kye-Sung Lee
- University of Rochester, The Institute of Optics, 275 Hutchinson Road, Rochester, New York 14627
- Korea Basic Science Institute, Center for Analytical Instrumentation Development, Daejeon 305-806, South Korea
| | - Jungeun Won
- University of Rochester, Department of Biomedical Engineering, 275 Hutchinson Road, Rochester, New York 14627
| | - Cristina Canavesi
- LighTopTech Corp., 150 Lucius Gordon Dr., Ste 115, West Henrietta, New York 14586
| | - Jannick P. Rolland
- University of Rochester, The Institute of Optics, 275 Hutchinson Road, Rochester, New York 14627
- University of Rochester, Center for Visual Science, 601 Elmwood Avenue, Rochester, New York 14642
- University of Rochester, Department of Biomedical Engineering, 275 Hutchinson Road, Rochester, New York 14627
- LighTopTech Corp., 150 Lucius Gordon Dr., Ste 115, West Henrietta, New York 14586
- Address all correspondence to: Jannick P. Rolland, E-mail:
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16
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Lee C, Kim K, Han S, Kim S, Lee JH, Kim HK, Kim C, Jung W, Kim J. Stimulated penetrating keratoplasty using real-time virtual intraoperative surgical optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:30502. [PMID: 24604471 PMCID: PMC4019417 DOI: 10.1117/1.jbo.19.3.030502] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 12/31/2013] [Accepted: 01/13/2014] [Indexed: 05/20/2023]
Abstract
An intraoperative surgical microscope is an essential tool in a neuro- or ophthalmological surgical environment. Yet, it has an inherent limitation to classify subsurface information because it only provides the surface images. To compensate for and assist in this problem, combining the surgical microscope with optical coherence tomography (OCT) has been adapted. We developed a real-time virtual intraoperative surgical OCT (VISOCT) system by adapting a spectral-domain OCT scanner with a commercial surgical microscope. Thanks to our custom-made beam splitting and image display subsystems, the OCT images and microscopic images are simultaneously visualized through an ocular lens or the eyepiece of the microscope. This improvement helps surgeons to focus on the operation without distraction to view OCT images on another separate display. Moreover, displaying the OCT live images on the eyepiece helps surgeon's depth perception during the surgeries. Finally, we successfully processed stimulated penetrating keratoplasty in live rabbits. We believe that these technical achievements are crucial to enhance the usability of the VISOCT system in a real surgical operating condition.
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Affiliation(s)
- Changho Lee
- Pohang University of Science and Technology (POSTECH), Departments of Electrical Engineering and Creative IT Engineering, Pohang 790-784, Republic of Korea
| | - Kyungun Kim
- Kyungpook National University, School of Electronics Engineering, Daegu 702-701, Republic of Korea
| | - Seunghoon Han
- Kyungpook National University, School of Electronics Engineering, Daegu 702-701, Republic of Korea
| | - Sehui Kim
- Kyungpook National University, School of Electronics Engineering, Daegu 702-701, Republic of Korea
| | - Jun Hoon Lee
- Metro Eye Center, Daegu 700-733, Republic of Korea
| | - Hong kyun Kim
- Kyungpook National University Hospital, Department of Ophthalmology, College of Medicine, Daegu 700-721, Republic of Korea
| | - Chulhong Kim
- Pohang University of Science and Technology (POSTECH), Departments of Electrical Engineering and Creative IT Engineering, Pohang 790-784, Republic of Korea
| | - Woonggyu Jung
- Ulsan National Institute of Science and Technology, School of Nano-Bioscience & Chemical Engineering, Ulsan 689-798, Republic of Korea
| | - Jeehyun Kim
- Kyungpook National University, School of Electronics Engineering, Daegu 702-701, Republic of Korea
- Address all correspondence to: Jeehyun Kim, E-mail:
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17
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Watanabe Y, Takahashi Y, Numazawa H. Graphics processing unit accelerated intensity-based optical coherence tomography angiography using differential frames with real-time motion correction. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:021105. [PMID: 23846119 DOI: 10.1117/1.jbo.19.2.021105] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate intensity-based optical coherence tomography (OCT) angiography using the squared difference of two sequential frames with bulk-tissue-motion (BTM) correction. This motion correction was performed by minimization of the sum of the pixel values using axial- and lateral-pixel-shifted structural OCT images. We extract the BTM-corrected image from a total of 25 calculated OCT angiographic images. Image processing was accelerated by a graphics processing unit (GPU) with many stream processors to optimize the parallel processing procedure. The GPU processing rate was faster than that of a line scan camera (46.9 kHz). Our OCT system provides the means of displaying structural OCT images and BTM-corrected OCT angiographic images in real time.
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Affiliation(s)
- Yuuki Watanabe
- Yamagata University, Bio-systems Engineering, Graduate School of Science and Engineering, 4-3-16 Johnan, Yonezawa, Yamagata 992-8510, Japan.
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18
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Han S, Lee C, Kim S, Jeon M, Kim J, Kim C. In vivo virtual intraoperative surgical photoacoustic microscopy. APPLIED PHYSICS LETTERS 2013; 103:203702. [PMID: 24343135 PMCID: PMC3843748 DOI: 10.1063/1.4830045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 10/28/2013] [Indexed: 05/10/2023]
Abstract
We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo.
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Affiliation(s)
- Seunghoon Han
- School of Electrical Engineering and Computer Science, Kyungpook National University, Daegu 702-701, South Korea
| | - Changho Lee
- Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea
| | - Sehui Kim
- School of Electrical Engineering and Computer Science, Kyungpook National University, Daegu 702-701, South Korea
| | - Mansik Jeon
- Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea
| | - Jeehyun Kim
- School of Electrical Engineering and Computer Science, Kyungpook National University, Daegu 702-701, South Korea
| | - Chulhong Kim
- Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, South Korea ; Department of Biomedical Engineering, The State University of New York at Buffalo, Buffalo, New York 14221, USA
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19
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Geo-Correction of High-Resolution Imagery Using Fast Template Matching on a GPU in Emergency Mapping Contexts. REMOTE SENSING 2013. [DOI: 10.3390/rs5094488] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Tao A, Peterson KA, Jiang H, Shao Y, Zhong J, Carey FC, Rosen EP, Wang J. Ultra-high resolution and long scan depth optical coherence tomography with full-phase detection for imaging the ocular surface. Clin Ophthalmol 2013; 7:1623-33. [PMID: 23976840 PMCID: PMC3747121 DOI: 10.2147/opth.s45122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We used a unique combination of four state-of-the-art technologies to achieve a high performance spectral domain optical coherence tomography system suitable for imaging the entire ocular surface. An ultra-high resolution, extended depth range, full-phase interferometry, and high-speed complementary metal-oxide semiconductor transistor camera detection provided unprecedented performance for the precise quantification of a wide range of the ocular surface. We demonstrated the feasibility of this approach by obtaining high-speed and high-resolution images of a model eye beyond the corneal-scleral junction. Surfaces determined from the images with a segmentation algorithm demonstrated excellent accuracy and precision.
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Affiliation(s)
- Aizhu Tao
- Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA ; School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, People's Republic of China
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21
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Cho NH, Jung U, Kim S, Jung W, Oh J, Kang HW, Kim J. High Speed SD-OCT System Using GPU Accelerated Mode for in vivo Human Eye Imaging. ACTA ACUST UNITED AC 2013. [DOI: 10.3807/josk.2013.17.1.068] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Huang Y, Liu X, Kang JU. Real-time 3D and 4D Fourier domain Doppler optical coherence tomography based on dual graphics processing units. BIOMEDICAL OPTICS EXPRESS 2012; 3:2162-74. [PMID: 23024910 PMCID: PMC3447558 DOI: 10.1364/boe.3.002162] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 08/15/2012] [Accepted: 08/16/2012] [Indexed: 05/04/2023]
Abstract
We present real-time 3D (2D cross-sectional image plus time) and 4D (3D volume plus time) phase-resolved Doppler OCT (PRDOCT) imaging based on configuration of dual graphics processing units (GPU). A GPU-accelerated phase-resolving processing algorithm was developed and implemented. We combined a structural image intensity-based thresholding mask and average window method to improve the signal-to-noise ratio of the Doppler phase image. A 2D simultaneous display of the structure and Doppler flow images was presented at a frame rate of 70 fps with an image size of 1000 × 1024 (X × Z) pixels. A 3D volume rendering of tissue structure and flow images-each with a size of 512 × 512 pixels-was presented 64.9 milliseconds after every volume scanning cycle with a volume size of 500 × 256 × 512 (X × Y × Z) voxels, with an acquisition time window of only 3.7 seconds. To the best of our knowledge, this is the first time that an online, simultaneous structure and Doppler flow volume visualization has been achieved. Maximum system processing speed was measured to be 249,000 A-scans per second with each A-scan size of 2048 pixels.
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Koo J, Lee C, Kang HW, Lee YW, Kim J, Oh J. Pulsed magneto-motive optical coherence tomography for remote cellular imaging. OPTICS LETTERS 2012; 37:3714-6. [PMID: 22941000 DOI: 10.1364/ol.37.003714] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We developed pulsed magneto-motive optical coherence tomography (PMM-OCT) to reduce environmental temperature in the measurement volume and to expand the effective magnetic field distance from a pulse source. The proposed PMM-OCT system consisted of a spectral-domain OCT system and a customarily designed electrical pulse generator. The enhanced magnetic field allowed the proposed system to be able to image magnetically labeled cells in a distance as far as 30 mm away from the pulse generator. As an easy and sensitive approach, our PMM-OCT may be beneficially applied to a molecular-level imaging systems.
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Affiliation(s)
- Jasung Koo
- Department of Mechatronics Engineering, Pukyong National University, Busan 608-739, South Korea
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24
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Non-destructive inspection methods for LEDs using real-time displaying Optical Coherence Tomography. SENSORS 2012; 12:10395-406. [PMID: 23112606 PMCID: PMC3472834 DOI: 10.3390/s120810395] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 07/24/2012] [Accepted: 07/24/2012] [Indexed: 11/16/2022]
Abstract
In this study, we report the applicability of two different Optical Coherence Tomography (OCT) technologies for inspecting Light Emitting Diode (LED) structures. Sectional images of a LED were captured using a Spectral Domain OCT (SD-OCT) system and a Swept Source OCT (SS-OCT) system. Their center wavelengths are 850 and 1,310 nm, respectively. We acquired cross-sectional two dimensional (2D) images of a normal LED and extracted sectional profiles to inspect possible wire disconnection that may be present in the LED manufacturing process. The SD-OCT and SS-OCT images were compared with each other in the same sample to study their advantages. The distribution of fluorescence material was observed more clearly with the SD-OCT of 850 nm wavelength, whereas the status of wire connection was clearer in the SS-OCT images with 1,310 nm wavelength. In addition, the volume of the fluorophore space was calculated from the OCT images. This is the first report that a nondestructive optical imaging modality such as OCT can be applied to finding screen defects in LED. We expect this method can improve the inspection efficacy over traditional inspection methods such as Charged Coupled Device (CCD) camera or X-ray instruments.
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