Publications by authors named "Woohyuk Lee"

Purpose: To identify how the inner retinal layer and microvasculature change with age by analyzing the relationships of ganglion cell-inner plexiform layer (GC-IPL) thickness, vessel density (VD), and the ratio of these measurements with age in healthy eyes.

Methods: Participants were divided into five groups according to age. The GC-IPL thickness, VD, and GC-IPL/VD ratio were compared among the groups.

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Fluorescein angiography is a crucial examination in ophthalmology to identify retinal and choroidal pathologies. However, this examination modality is invasive and inconvenient, requiring intravenous injection of a fluorescent dye. In order to provide a more convenient option for high-risk patients, we propose a deep-learning-based method to translate fundus photography into fluorescein angiography using Energy-based Cycle-consistent Adversarial Networks (CycleEBGAN) We propose a deep-learning-based method to translate fundus photography into fluorescein angiography using CycleEBGAN.

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Spectral-domain optical coherence tomography (SD-OCT) must accurately identify and measure the peripapillary retinal nerve fiber layer (pRNFL) thickness to improve the repeatability and reproducibility, and reduce measurement errors. Because Weiss ring can be located in front of the optic disc, we hypothesized that it may affect pRNFL thickness measurements obtained using SD-OCT. We retrospectively reviewed the medical records of patients with (group W) and without (group N) Weiss ring, observed on OCT fundus image and an RNFL map devised using SD-OCT.

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In this work, a cerium/tetraethylenepentamine dithiocarbamate complex was synthesized and evaluated for the corrosion inhibition capability on an AA2024-T3 Al alloy in a 3.5% NaCl medium. The synthesized compounds were characterized via spectroscopic techniques.

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In a previous study, we identified biocular asymmetries in fundus photographs, and macula was discriminative area to distinguish left and right fundus images with > 99.9% accuracy. The purposes of this study were to investigate whether optical coherence tomography (OCT) images of the left and right eyes could be discriminated by convolutional neural networks (CNNs) and to support the previous result.

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A new approach to the recycling of spent coffee grounds is described in which lignin, a chemical component of spent coffee, is used as an electrolyte additive in aluminum-air batteries. The effect of lignin on the performance of aluminum-air batteries has been investigated by weight loss measurement, galvanostatic discharge test, and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiency is improved up to 37.

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Background: We aimed to study the bilateral choroidal thickness (CT) symmetry and difference in uncomplicated pachychoroid subjects using wide-field swept-source optical coherence tomography (SS-OCT).

Methods: All subjects underwent a wide-field 16-mm one-line scan using SS-OCT. Bilateral CT was measured at, and compared among, the following 12 points: three points at 900-µm intervals from the nasal optic disc margin (nasal peripapillary area), one point at the subfovea, six points at 900-µm intervals from the fovea to the nasal and temporal areas (macular area), and two peripheral points 5400 and 8100 µm from the fovea (peripheral area).

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Purpose: To identify the impact of hypertension (HTN) on macular microvasculature in type 2 diabetes (T2DM) patients without clinical diabetic retinopathy.

Methods: In this retrospective cross-sectional study, subjects were divided into three groups: controls (control group), patients with T2DM (DM group), and patients with both T2DM and HTN (DM + HTN group). The vessel length density (VD) was compared among the groups.

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Type 2 diabetes mellitus (T2DM) and hypertension (HTN) are both relatively common systemic diseases and cause damage to the retina, such as inner retina reduction and microvascular impairment. The purpose of this study was to identify peripapillary retinal nerve fiber layer (pRNFL) damage by diabetic neurodegeneration and the effects of HTN on the pRNFL thickness in patients with T2DM without clinical diabetic retinopathy. Subjects were divided into three groups: healthy control subjects (group 1), patients with T2DM (group 2), and patients with both diabetes and HTN (group 3).

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Optical coherence tomography (OCT) is a noninvasive method that can quickly and accurately examine the eye at the cellular level. Several studies have used OCT for analysis of anterior chamber cells. However, these studies have several limitations.

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Article Synopsis
  • High sensitivity detection of tumor markers like vascular endothelial growth factor (VEGF) is crucial for quick cancer diagnosis and treatment.
  • An electrochemical aptasensor utilizing nanocomposites of polyaniline (PANI) and carbon nanotubes (CNT) shows promise due to its cost-effectiveness and quantitative capabilities.
  • This aptasensor can detect VEGF at very low concentrations (as low as 0.4 pg/mL) and maintains stability and reproducibility, making it suitable for future non-invasive diagnostic applications.
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Purpose: The purpose of this study to identify the effects of prolonged type 2 diabetes (T2DM) on the peripapillary retinal nerve fiber layer (pRNFL) and peripapillary microvasculature in patients with prolonged T2DM without clinical diabetic retinopathy (DR).

Methods: Subjects were divided into 3 groups: controls (control group; 153 eyes), patients with T2DM < 10 years (DM group 1; 136 eyes), and patients with T2DM ≥ 10 years (DM group 2; 74 eyes). The pRNFL thickness and peripapillary superficial vessel density (VD) were compared.

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Purpose: The purpose of this paper was to study the bilateral choroidal thickness (CT) symmetry and differences in healthy individuals using wide-field swept-source optical coherence tomography (SS-OCT).

Methods: All participants underwent a wide-field 16-mm 1-line scan using SS-OCT. CTs were measured at the following 12 points: 3 points at 900 µm, 1800 µm, and 2700 µm away from the nasal optic disc margin (nasal peripapillary area), 1 point at the subfovea, 6 points at 900 µm, 1800 µm, and 2700 µm away from the subfovea to the nasal and temporal areas (macular area), and 2 peripheral points at 2700 and 5400 µm from temporal point 3 (peripheral area).

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Purpose: To identify the effects of prolonged type 2 diabetes (T2DM) on macular microcirculation and the inner retinal layer in diabetic eyes without clinical diabetic retinopathy (DR).

Methods: 97, 92, and 57 eyes in the control, patients with T2DM < 10 years (DM group one), and patients with T2DM ≥ 10 years (DM group two) were enrolled. The ganglion cell-inner plexiform layer (GC-IPL) thickness and superficial vessel density (VD) were compared.

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To analyze longitudinal changes in peripapillary retinal nerve fiber layer (pRNFL) thicknesses over time in the fellow eyes of patients with unilateral retinal vein occlusion (RVO). A total of 47 patients with unilateral RVO and 47 healthy controls were enrolled. The mean and sectoral pRNFL thicknesses were measured using spectral domain-optical coherence tomography at 1 year intervals, and followed for 3 years.

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The purpose of this study was to investigate changes in peripapillary microvasculature using optical coherence tomography angiography (OCTA) in systemic hypertension (HTN) patients. This was a cross-sectional study. Based on the duration of HTN, seventy-eight HTN patients were divided into two groups.

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Purpose: To determine the comparability of choroidal thickness (ChT) measurements using swept source (SS) and spectral domain (SD) optical coherence tomography (OCT) devices in patients with pachychoroid diseases.

Methods: Patients with pachychoroid diseases were recruited. OCT scans were performed sequentially with a Cirrus HD OCT 5000 and Plex Elite 9000.

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Purpose: To determine longitudinal changes in the peripapillary retinal nerve fiber layer (pRNFL) thickness in patients with hypertension (HTN).

Methods: Participants without any ophthalmic disease were divided into two groups: an HTN group (50 eyes) that included patients with HTN for ≥5 years and a control group. After the initial visit, pRNFL thicknesses were measured four more times at 1-year intervals using spectral-domain optical coherence tomography.

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Importance: Although goniotomy is known to be successful in treating congenital glaucoma, its effect in adult glaucoma patients remains unclear.

Background: To evaluate the efficacy and safety of goniotomy performed simultaneously with cataract surgery in treatment of open-angle glaucoma (OAG).

Design: Retrospective comparative study.

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Purpose: To investigate the central macular thickness (CMT) and retinal nerve fiber layer (RNFL) thickness in eyes with Vogt-Koyanagi-Harada (VKH) disease associated with optic disc swelling and serous retinal detachment through a 24-month follow-up period.

Methods: We prospectively investigated 28 eyes of 14 treatment-naïve patients with acute VKH disease associated with optic disc swelling and serous retinal detachment and 30 eyes of 15 normal individuals to compare changes in the CMT and average RNFL thickness.

Results: The CMT was significantly lower in the eyes of the VKH group at 12 and 24 months.

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Objective: To analyse the longitudinal changes in the thickness of the central macula and retinal nerve fibre layer (RNFL) in patients with hypertensive retinopathy (HTNR) using spectral-domain optical coherence tomography (SD-OCT).

Methods: This was a prospective cohort study. We studied 18 eyes of patients with HTNR of grade IV who had been followed up for more than 1 year, and 36 normal eyes (without any relevant medical history; the control group).

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Patients with congenital ocular motor apraxia (OMA) typically show head thrusts while attempting to shift gaze. In congenital OMA, this compensatory head motion mostly occurs in the horizontal plane. Two patients with acquired palsy of voluntary vertical gaze and continuous upward gaze deviation, one from aortic surgery and the other from multiple infarctions involving the mesodiencephalic junction, showed intermittent downward head thrusting to redirect the eyes straight ahead or downward.

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Purpose: To determine the repeatability of measuring the thickness of the central macula, retinal nerve fiber layer, and ganglion cell-inner plexiform layer (GC-IPL) using spectral domain optical coherence tomography (Cirrus HD-OCT) in eyes with age-related macular degeneration.

Methods: One hundred and thirty-four eyes were included. The measurement repeatability was assessed by an experienced examiner who performed two consecutive measurements using a 512 × 128 macular cube scan and a 200 × 200 optic disk cube scan.

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Microfluidic platforms provide several unique advantages for drug development. In the production of drug carriers, physical properties such as size and shape, and chemical properties such as drug composition and pharmacokinetic parameters, can be modified simply and effectively by tuning the flow rate and geometries. Large numbers of carriers can then be fabricated with minimal effort and with little to no batch-to-batch variation.

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