Handheld Optical Coherence Tomography Scanner for Primary Care Diagnostics

Jung, Woonggyu,Kim, Jeehyun,Jeon, Mansik,Chaney, Eric J.,Stewart, Charles N.,Boppart, Stephen A. IEEE 2011 IEEE Transactions on Biomedical Engineering Vol.58 No.3

<P>The goal of this study is to develop an advanced point-of-care diagnostic instrument for use in a primary care office using handheld optical coherence tomography (OCT). This system has the potential to enable earlier detection of diseases and accurate image-based diagnostics. Our system was designed to be compact, portable, user-friendly, and fast, making it well suited for the primary care office setting. The unique feature of our system is a versatile handheld OCT imaging scanner which consists of a pair of computer-controlled galvanometer-mounted mirrors, interchangeable lens mounts, and miniaturized video camera. This handheld scanner has the capability to guide the physician in real time for finding suspicious regions to be imaged by OCT. In order to evaluate the performance and use of the handheld OCT scanner, the anterior chamber of a rat eye and in vivo human retina, cornea, skin, and tympanic membrane were imaged. Based on this feasibility study, we believe that this new type of handheld OCT device and system has the potential to be an efficient point-of-care imaging tool in primary care medicine.</P>

Collaborator Session (hosted by NCR)-Skin Barrier Research in NCR projects : CS 3: The Potential of Optical Coherence Tomography in Tissue Engineering

( Woonggyu Jung ) 한국피부장벽학회 2015 한국피부장벽학회지 Vol.17 No.2

Optical imaging inherently offers many advantages which are well suited for evaluating the study of cell and tissue engineering: (1) higher spatial resolution and sensitivity, (2) tissue and cellular information based on scattering, absorption, and fluorescence, and (3) availability of contrast agents for specific targeted biomarkers. Among various optical imaging modalities, optical coherence tomography (OCT) is the most emerging imaging technology which allows real-time cross-sectional imaging with high resolutions. OCT could be a very promising technique which has the potential to be used as an adjunct to histological tissue observation when it is not practical to take specimens for histological processing, when large areas of tissue need investigating, or when rapid microscopic imaging is needed. This presentation will describe the use of OCT as an advanced imaging tool for fast tissue screening and directed histological tissue sectioning. The material covers the latest work of label-free optical imaging using optical coherence tomography (OCT) for large-field of view tissue imaging. Specifically, the talk will highlight quantitative OCT for evaluating artificial blood vessel and engineered skin. Long term objective of these researches is to develop high resolution and complementary imaging systems to better assess the specimens in tissue engineering research and to enable applying it to dynamic study.

Optical coherence tomography for advanced screening in the primary care office.

Shelton, Ryan L,Jung, Woonggyu,Sayegh, Samir I,McCormick, Daniel T,Kim, Jeehyun,Boppart, Stephen A Wiley 2014 Journal of Biophotonics Vol.7 No.7

<P>Optical coherence tomography (OCT) has long been used as a diagnostic tool in the field of ophthalmology. The ability to observe microstructural changes in the tissues of the eye has proved very effective in diagnosing ocular disease. However, this technology has yet to be introduced into the primary care office, where indications of disease are first encountered. We have developed a portable, handheld imaging probe for use in the primary care setting and evaluated its tissue site accessibility, ability to observe diseased tissue, and screening capabilities in in vivo human patients, particularly for pathologies related to the eye, ear and skin. Various stages of diabetic retinopathy were investigated using the handheld probe and early-stage diabetic retinopathy was flagged as abnormal from the OCT images. At such early stages of disease, it is difficult to observe abnormalities with the limited tools that are currently available to primary care physicians. These results indicate that OCT shows promise to transform from being a diagnostic technology in the medical and surgical specialities to a screening technology in the primary care office and at the front-line of healthcare.</P>

Substrate curvature affects the shape, orientation, and polarization of renal epithelial cells

Yu, Sun-Min,Oh, Jung Min,Lee, Junwon,Lee-Kwon, Whaseon,Jung, Woonggyu,Amblard, Franç,ois,Granick, Steve,Cho, Yoon-Kyoung Elsevier 2018 ACTA BIOMATERIALIA Vol.77 No.-

<P><B>Abstract</B></P> <P>The unique structure of kidney tubules is representative of their specialized function. Because maintaining tubular structure and controlled diameter is critical for kidney function, it is critical to understand how topographical cues, such as curvature, might alter cell morphology and biological characteristics. Here, we examined the effect of substrate curvature on the shape and phenotype of two kinds of renal epithelial cells (MDCK and HK-2) cultured on a microchannel with a broad range of principal curvature. We found that cellular architecture on curved substrates was closely related to the cell type-specific characteristics (stiffness, cell–cell adherence) of the cells and their density, as well as the sign and degree of curvature. As the curvature increased on convex channels, HK-2 cells, having lower cell stiffness and monolayer integrity than those of MDCK cells, aligned their in-plane axis perpendicular to the channel but did not significantly change in morphology. By contrast, MDCK cells showed minimal change in both morphology and alignment. However, on concave channels, both cell types were elongated and showed longitudinal directionality, although the changes in MDCK cells were more conservative. Moreover, substrate curvature contributed to cell polarization by enhancing the expression of apical and basolateral cell markers with height increase of the cells. Our study suggests curvature to be an important guiding principle for advanced tissue model developments, and that curved and geometrically ambiguous substrates can modulate the cellular morphology and phenotype.</P> <P><B>Statement of Significance</B></P> <P>In many tissues, such as renal tubules or intestinal villi, epithelial layers exist in naturally curved forms, a geometry that is not reproduced by flat cultures. Because maintaining tubular structure is critical for kidney function, it is important to understand how topographical cues, such as curvature, might alter cell morphology and biological characteristics. We found that cellular architecture on curved substrates was closely related to cell type and density, as well as the sign and degree of the curvature. Moreover, substrate curvature contributed to cell polarization by enhancing the expression of apical and basolateral cell markers with height increase. Our results suggested that substrate curvature might contribute to cellular architecture and enhance the polarization of kidney tubule cells.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Lamellar keratoplasty using position-guided surgical needle and M-mode optical coherence tomography

Shin, Sungwon,Bae, Jung Kweon,Ahn, Yujin,Kim, Hyeongeun,Choi, Geonho,Yoo, Young-Sik,Joo, Choun-Ki,Moon, Sucbei,Jung, Woonggyu SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS 2017 JOURNAL OF BIOMEDICAL OPTICS Vol.22 No.12

Full-range k-domain linearization in spectral-domain optical coherence tomography

Jeon, Mansik,Kim, Jeehyun,Jung, Unsang,Lee, Changho,Jung, Woonggyu,Boppart, Stephen A. The Optical Society 2011 Applied Optics Vol.50 No.8

<P>A full-bandwidth k-domain linearization method for spectral-domain optical coherence tomography (SD-OCT) is demonstrated. The method uses information of the wavenumber-pixel-position provided by a translating-slit-based wavelength filter. For calibration purposes, the filter is placed either after a broadband source or at the end of the sample path, and the filtered spectrum with a narrowed line width (??.5?m) is incident on a line-scan camera in the detection path. The wavelength-swept spectra are co-registered with the pixel positions according to their central wavelengths, which can be automatically measured with an optical spectrum analyzer. For imaging, the method does not require a filter or a software recalibration algorithm; it simply resamples the OCT signal from the detector array without employing rescaling or interpolation methods. The accuracy of k-linearization is maximized by increasing the k-linearization order, which is known to be a crucial parameter for maintaining a narrow point-spread function (PSF) width at increasing depths. The broadening effect is studied by changing the k-linearization order by undersampling to search for the optimal value. The system provides more position information, surpassing the optimum without compromising the imaging speed. The proposed full-range k-domain linearization method can be applied to SD-OCT systems to simplify their hardware/software, increase their speed, and improve the axial image resolution. The experimentally measured width of PSF in air has an FWHM of 8? at the edge of the axial measurement range. At an imaging depth of 2.5?m, the sensitivity of the full-range calibration case drops less than 10?B compared with the uncompensated case.</P>

안구 영상을 위한 OCT용 손잡이 형 프로브의 개발

조남현(Nam Hyun Cho),정웅규(Woonggyu Jung),정운상(Unsang Jung),Stephen A.Boppart,심재훈(Jae hoon Shim),김지현(Jeehyun Kim) 大韓電子工學會 2011 電子工學會論文誌-SC (System and control) Vol.48 No.1

본 연구에서는 안구 영상을 위한 OCT용 손잡이 형 프로브를 개발하였다. 프로브는 휴대하기 간편한 손잡이 형태로 구현하였으며, 어댑터의 대물렌즈를 교체함으로써 각막(cornea)과 망막(retina) 모두 영상화 할 수 있도록 설계 하였다. 시스템의 성능검증을 위해 in vivo 로 실험용 쥐의 눈 영상을 2D로 획득하였으며, 획득한 영상을 3D 영상으로 재구성하였다. 3D 영상은 쥐의 미세한 부분의 구조를 잘 나타내었으며, 움직임에 의한 흔들림 현상(Motion artifact)이 나타나지 않았으므로 개발된 OCT시스템의 이미지 디스플레이 속도는 생체 내 실험(in vivo)에 적합함을 알 수 있었다. We have developed a hand-held probe for an ophthalmic OCT system. The hand-held probe for imaging was designed to be compact and portable. The cornea and retinal images were acquired by replacing the objective lens at the front of the probe. To verify the performance of the hand-held OCT probe, we acquired two dimensional OCT image of the rat eye in vivo and reconstructed three dimensional rat eye rendering images. In vivo 3D OCT images were showed distinct structural information in the posterior and anterior chamber with minimal motion artifacts. Thereby, OCT imaging speed is suitable for an dynamic in vivo experiment.

Quantification and visualization of metastatic lung tumors in mice

Lee Ha Neul,Kim Seyl,Park Sooah,Jung Woonggyu,Kang Jin Seok 한국독성학회 2022 Toxicological Research Vol.38 No.4

Histopathological examination is important for the diagnosis of various diseases. Conventional histopathology provides a two-dimensional view of the tissues, and requires the tissue to be extracted, fixed, and processed using histotechnology techniques. However, there is an increasing need for three-dimensional (3D) images of structures in biomedical research. The objective of this study was to develop reliable, objective tools for visualizing and quantifying metastatic tumors in mouse lung using micro-computed tomography (micro-CT), optical coherence tomography (OCT), and field emission-scanning electron microscopy (FE-SEM). Melanoma cells were intravenously injected into the tail vein of 8-week-old C57BL/6 mice. The mice were euthanized at 2 or 4 weeks after injection. Lungs were fixed and examined by micro-CT, OCT, FE-SEM, and histopathological observation. Micro-CT clearly distinguished between tumor and normal cells in surface and deep lesions, thereby allowing 3D quantification of the tumor volume. OCT showed a clear difference between the tumor and surrounding normal tissues. FE-SEM clearly showed round tumor cells, mainly located in the alveolar wall and growing inside the alveoli. Therefore, whole-tumor 3D imaging successfully visualized the metastatic tumor and quantified its volume. This promising approach will allow for fast and label-free 3D phenotyping of diverse tissue structures.

Evaluating the effects of organic matter bioavailability on nanofiltration membrane using real-time monitoring

Park, Sanghun,You, Jeongyeop,Ahn, Yujin,Jung, Woonggyu,Kim, Jihye,Lee, Sungyun,Park, Jongkwan,Cho, Kyung Hwa Elsevier 2018 Journal of membrane science Vol.548 No.-

<P><B>Abstract</B></P> <P>We studied the influence of bioavailability of organic matter on membrane fouling layer development by comparing the filtration performance of two feed waters (wetland water and graywater). Dissolved organic carbon (DOC) concentration, size exclusion chromatography (SEC), and fluorescence excitation-emission matrix (FEEM) were used to characterize the bioavailability of organic matter in these water samples during the nanofiltration process. The wetland sample contained a high proportion of humic acid- and fulvic acid-like matter with low bioavailability, whereas the graywater sample comprised substantial amounts of aromatic proteins and microbial byproduct-like matter with high bioavailability. In addition, the molecular size distribution revealed that the wetland sample contained a large portion of recalcitrant organic matter, whereas the graywater sample contained easily bioavailable organic matter. After the filtration experiment, the DOC of the wetland sample decreased to 4.8mgC/L, whereas the graywater sample resulted in a lower DOC concentration of 3.4mgC/L. Optical coherence tomography (OCT) illustrated real-time variations in the fouling layer morphology, providing both 2D and 3D images. In addition, confocal laser scanning microscopy (CLSM) quantified the bacterial volume in the fouling layer. The wetland sample yielded a bacterial volume of 11.8µm<SUP>3</SUP>/μm<SUP>2</SUP> from a total fouling volume of 103µm<SUP>3</SUP>/μm<SUP>2</SUP>, whereas the graywater sample yielded a bacterial volume of 53.2µm<SUP>3</SUP>/μm<SUP>2</SUP> from a total fouling layer volume of 134µm<SUP>3</SUP>/μm<SUP>2</SUP>. Fitting of the two-phase Monod model to the fouling layer growth on the membrane resulted in lower-yield coefficients (i.e., the volumes produced per unit amount of substrate, <SUB> Y xs </SUB> ) of 7.46 and 27.95µm<SUP>3</SUP>/μm<SUP>2</SUP> in wetland water and higher-yield coefficients of 13.17 and 47.53µm<SUP>3</SUP>/μm<SUP>2</SUP> in the graywater at first and second phase, respectively. This study addresses the quantitative evaluation of the organic matter bioavailability in terms of membrane fouling using OCT images and a two-phase Monod model.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The difference of bioavailability of DOM influenced the amount of fouling layer growth. </LI> <LI> In situ OCT monitoring provided 2D and 3D morphology of the fouling layer and quantified the volume. </LI> <LI> Two-phase Monod model evaluated the influence of bioavailability of DOM on fouling layer growth. </LI> </UL> </P>

In vivo imaging of middle-ear and inner-ear microstructures of a mouse guided by SD-OCT combined with a surgical microscope.

Cho, Nam Hyun,Jang, Jeong Hun,Jung, Woonggyu,Kim, Jeehyun Optical Society of America 2014 Optics express Vol.22 No.8

<P>We developed an augmented-reality system that combines optical coherence tomography (OCT) with a surgical microscope. By sharing the common optical path in the microscope and OCT, we could simultaneously acquire OCT and microscope views. The system was tested to identify the middle-ear and inner-ear microstructures of a mouse. Considering the probability of clinical application including otorhinolaryngology, diseases such as middle-ear effusion were visualized using in vivo mouse and OCT images simultaneously acquired through the eyepiece of the surgical microscope during surgical manipulation using the proposed system. This system is expected to realize a new practical area of OCT application.</P>