1. Articles from Xiulan Zhang

    1-24 of 24
    1. Multi-modal Machine Learning using Visual Fields and Peripapillary Circular OCT Scans in Detection of Glaucomatous Optic Neuropathy

      Multi-modal Machine Learning using Visual Fields and Peripapillary Circular OCT Scans in Detection of Glaucomatous Optic Neuropathy

      Purpose: To develop and test a multi-modal artificial intelligence (AI) algorithm, FusionNet, using the pattern deviation probability plots (PDPs) from visual field (VF) reports and circular peripapillary optical coherence tomography (OCT) to detect glaucomatous optic neuropathy (GON). Design: Cross-sectional study. Subjects: A total of 2463 pairs of VF and OCT images from 1083 patients. Methods: A novel deep learning algorithm (FusionNet) based on bimodal input of VF-OCT paired data was developed to detect GON. VF data were collected using Humphrey Field Analyzer (HFA). OCT images were collected from three types of devices (DRI-OCT, Cirrus OCT and Spectralis OCT). A total ...

      Read Full Article
    2. Analysis of Iris volume using swept-source optical coherence tomography in patients with type 2 diabetes mellitus

      Analysis of Iris volume using swept-source optical coherence tomography in patients with type 2 diabetes mellitus

      Purpose: To evaluate iris volume before and after pupil dilation using swept-source anterior segment optical coherence tomography (SS-ASOCT) and investigate the associated factors of iris volume and iris volume change after pupil dilation in patients with type 2 diabetes mellitus (T2DM). Methods: A cross-sectional study was conducted in Zhongshan Ophthalmic Center among T2DM registered patients in the community of Guangzhou, China. Anterior chamber volume (ACV), iris volume, anterior chamber depth (ACD), angle opening distance at 500 μm (AOD 500) and pupil diameter were estimated using SS-ASOCT (CASIA; Tomey, Nagoya, Japan). Venous blood was taken for the measurement of glycosylated haemoglobin ...

      Read Full Article
    3. Deep Relation Transformer for Diagnosing Glaucoma with Optical Coherence Tomography and Visual Field Function

      Deep Relation Transformer for Diagnosing Glaucoma with Optical Coherence Tomography and Visual Field Function

      Glaucoma is the leading reason for irreversible blindness. Early detection and timely treatment of glaucoma are essential for preventing visual field loss or even blindness. In clinical practice, Optical Coherence Tomography (OCT) and Visual Field (VF) exams are two widely-used and complementary techniques for diagnosing glaucoma. OCT provides quantitative measurements of the optic nerve head (ONH) structure, while VF test is the functional assessment of peripheral vision. In this paper, we propose a Deep Relation Transformer (DRT) to perform glaucoma diagnosis with OCT and VF information combined. A novel deep reasoning mechanism is proposed to explore implicit pairwise relations between ...

      Read Full Article
    4. The anterior and posterior biometric characteristics in primary angle-closure disease: Data based on anterior segment optical coherence tomography and swept-source optical coherence tomography

      The anterior and posterior biometric characteristics in primary angle-closure disease: Data based on anterior segment optical coherence tomography and swept-source optical coherence tomography

      Purpose: Obtaining a better understanding of the pathogenesis of primary angle-closure disease (PACD) still requires studies that provide measurements of anterior and posterior biometric characteristics together and that assess the relationship between them. Methods: In total, 201 eyes were enrolled in this cross-sectional study: 50 normal controls, 49 primary angle-closure suspect (PACS), 38 primary angle closure (PAC), and 64 primary angle-closure glaucoma (PACG) eyes. The anterior and posterior structural features were measured by anterior segment optical coherence tomography and swept-source optical coherence tomography. Results: All PACD groups had smaller anterior chamber depth (ACD), anterior chamber area (ACA), anterior chamber volume ...

      Read Full Article
    5. Angle-closure assessment in anterior segment OCT images via deep learning

      Angle-closure assessment in anterior segment OCT images via deep learning

      Precise characterization and analysis of anterior chamber angle (ACA) are of great importance in facilitating clinical examination and diagnosis of angle-closure disease. Currently, the gold standard for diagnostic angle assessment is observation of ACA by gonioscopy. However, gonioscopy requires direct contact between the gonioscope and patients' eye, which is uncomfortable for patients and may deform the ACA, leading to false results. To this end, in this paper, we explore a potential way for grading ACAs into open-, appositional- and synechial angles by Anterior Segment Optical Coherence Tomography (AS-OCT), rather than the conventional gonioscopic examination. The proposed classification schema can be ...

      Read Full Article
    6. Longitudinal Changes in Macular Optical Coherence Tomography Angiography Metrics in Primary Open-Angle Glaucoma With High Myopia: A Prospective Study

      Longitudinal Changes in Macular Optical Coherence Tomography Angiography Metrics in Primary Open-Angle Glaucoma With High Myopia: A Prospective Study

      Purpose : To characterize longitudinal changes in macular microvasculature as quantified from optical coherence tomography angiography (OCTA) metrics in primary open-angle glaucoma (POAG) eyes with and without high myopia. Methods : In total, 63 and 61 POAG eyes with and without high myopia, respectively, underwent swept-source OCTA imaging in at least four follow-up visits at an ophthalmic center, with a scanning protocol of 3- × 3-mm centered at the fovea. The foveal avascular zone (FAZ) area, FAZ circularity, and vessel density (VD) in both the superficial (SCP) and deep capillary plexuses (DCP) were measured. The rate of change in macular OCTA metrics over ...

      Read Full Article
    7. Reduced Pulsatile Trabecular Meshwork Motion in Eyes With Primary Open Angle Glaucoma Using Phase-Sensitive Optical Coherence Tomography

      Reduced Pulsatile Trabecular Meshwork Motion in Eyes With Primary Open Angle Glaucoma Using Phase-Sensitive Optical Coherence Tomography

      Purpose: The purpose of this study was to investigate the difference in pulsatile trabecular meshwork (TM) motion between normal and eyes with POAG using phase-sensitive optical coherence tomography (PhS-OCT). Methods: In this cross-sectional study, eight healthy subjects (16 eyes) and nine patients with POAG (18 eyes) were enrolled. A laboratory-based prototype PhS-OCT system was used to measure pulsatile TM motion. PhS-OCT images were analyzed to obtain parameters of pulsatile TM motion (i.e. maximum velocity [MV] and cumulative displacement [CDisp]). Outflow facility and ocular pulse amplitude were measured using pneumotonography. Detection sensitivity was compared among various parameters by calculating the ...

      Read Full Article
    8. Open-Appositional-Synechial Anterior Chamber Angle Classification in AS-OCT Sequences

      Open-Appositional-Synechial Anterior Chamber Angle Classification in AS-OCT Sequences

      Anterior chamber angle (ACA) classification is a key step in the diagnosis of angle-closure glaucoma in Anterior Segment Optical Coherence Tomography (AS-OCT). Existing automated analysis methods focus on a binary classification system (i.e., open angle or angle-closure) in a 2D AS-OCT slice. However, clinical diagnosis requires a more discriminating ACA three-class system (i.e., open, appositional, or synechial angles) for the benefit of clinicians who seek better to understand the progression of the spectrum of angle-closure glaucoma types. To address this, we propose a novel sequence multi-scale aggregation deep network (SMA-Net) for open-appositional-synechial ACA classification based on an AS-OCT ...

      Read Full Article
    9. AGE challenge: Angle Closure Glaucoma Evaluation in Anterior Segment Optical Coherence Tomography

      AGE challenge: Angle Closure Glaucoma Evaluation in Anterior Segment Optical Coherence Tomography

      Angle closure glaucoma (ACG) is a more aggressive disease than open-angle glaucoma, where the abnormal anatomical structures of the anterior chamber angle (ACA) may cause an elevated intraocular pressure and gradually lead to glaucomatous optic neuropathy and eventually to visual impairment and blindness. Anterior Segment Optical Coherence Tomography (AS-OCT) imaging provides a fast and contactless way to discriminate angle closure from open angle. Although many medical image analysis algorithms have been developed for glaucoma diagnosis, only a few studies have focused on AS-OCT imaging. In particular, there is no public AS-OCT dataset available for evaluating the existing methods in a ...

      Read Full Article
    10. AGE Challenge: Angle Closure Glaucoma Evaluation in Anterior Segment Optical Coherence Tomography

      AGE Challenge: Angle Closure Glaucoma Evaluation in Anterior Segment Optical Coherence Tomography

      Angle closure glaucoma (ACG) is a more aggressive disease than open-angle glaucoma, where the abnormal anatomical structures of the anterior chamber angle (ACA) may cause an elevated intraocular pressure and gradually leads to glaucomatous optic neuropathy and eventually to visual impairment and blindness. Anterior Segment Optical Coherence Tomography (AS-OCT) imaging provides a fast and contactless way to discriminate angle closure from open angle. Although many medical image analysis algorithms have been developed for glaucoma diagnosis, only a few studies have focused on AS-OCT imaging. In particular, there is no public AS-OCT dataset available for evaluating the existing methods in a ...

      Read Full Article
    11. Automatic Segmentation and Visualization of Choroid in OCT with Knowledge Infused Deep Learning

      Automatic Segmentation and Visualization of Choroid in OCT with Knowledge Infused Deep Learning

      The choroid provides oxygen and nourishment to the outer retina thus is related to the pathology of various ocular diseases. Optical coherence tomography (OCT) is advantageous in visualizing and quantifying the choroid in vivo, because it does not suffer from the information contamination of the outer retina in fundus photography and scanning laser ophthalmoscopy and the resolution deficiency in ocular ultrasound. We propose a biomarker infused global-to-local network, for the choroid segmentation. It leverages the thickness of the choroid layer, which is a primary biomarker in clinic, as a constraint to improve the segmentation accuracy. We also design a global-to-local ...

      Read Full Article
    12. Clock position-based iris bow configuration after laser peripheral iridotomy in Chinese angle closure eyes: a swept source optical coherence tomography study

      Clock position-based iris bow configuration after laser peripheral iridotomy in Chinese angle closure eyes: a swept source optical coherence tomography study

      Background To determine how many measurements should be evaluated to determine the iris bow and evaluate changes of iris bow at 12 clock positions after LPI in primary angle closure eyes. Methods A total of 93 primary angle closure eyes in 93 Chinese patients were enrolled. Anterior iris bowing was evaluated at 12 clock positions and 4 clock positions (3, 6, 9, and 12 o’clock) before, 1 week and 3 months after LPI using swept source optical coherence tomography. Results At baseline, almost all of the eyes exhibited an iris bow when measured using 12 clock positions, consistent with ...

      Read Full Article
    13. Upside-down position leads to choroidal expansion and anterior chamber shallowing: OCT study

      Upside-down position leads to choroidal expansion and anterior chamber shallowing: OCT study

      Background To determine whether dynamic changes in choroidal thickness (CT) cause shallowing of the anterior chamber. Methods 34 healthy volunteers were enrolled. The participants in our study adopted the upside-down position for 1.5 min, which was the model we used to study the dynamic changes in CT. Intraocular pressure (IOP) elevation, optical coherence tomography images of the choroid and anterior chamber were obtained at baseline, after being in an upside-down position in an inversion machine and after 15 min of rest. The changes in IOP, anterior chamber and choroidal blood flow between the baseline and the upside-down position were ...

      Read Full Article
    14. A prospective case-control study comparing optical coherence tomography characteristics in neuromyelitis optica spectrum disorder- optic neuritis and idiopathic optic neuritis

      A prospective case-control study comparing optical coherence tomography characteristics in neuromyelitis optica spectrum disorder- optic neuritis and idiopathic optic neuritis

      Background Neuromyelitis optica spectrum disorder-optic neuritis (NMOSD-ON) can now be distinguished from other types of ON as a specific disease by the Aquaporin-4 antibody (AQP4-Ab) test. NMOSD-ON can cause severe retinal nerve fiber layer (RNFL) damage. The optical coherence tomography (OCT) characteristics between NMOSD- ON and idiopathic optic neuritis (IDON) were seldom studied in Asians. Methods This prospective case-control study involved 152 eyes from 143 optic neuritis (ON) patients. All the patients were divided into either the NMOSD-ON group or the IDON group based on the AQP4-Ab test. The retinal nerve fiber layer thickness (RNFLT), retinal thickness (RT), and choroidal ...

      Read Full Article
    15. Re: Kwon et al.: Subclassification of primary angle closure using anterior segment optical coherence tomography and ultrasound biomicroscopic parameters (Ophthalmology. 2017;124:1039-1047)

      Re: Kwon et al.: Subclassification of primary angle closure using anterior segment optical coherence tomography and ultrasound biomicroscopic parameters (Ophthalmology. 2017;124:1039-1047)

      To the Editor: We read with interest the article by Sung et al. 1 In this observational study, the authors concluded that the most distinct difference between the 2 subgroups in the cluster analysis was trabecular–ciliary process angle (TCA) and that the position of the ciliary body is important in subclassifying primary angle closure. However, there are several limitations that may affect the results. First, in the study, the authors reported that gonioscopy and image analysis using ImageJ was all conducted by a single researcher. These 2 measurements, however, both can be influenced by observers' subjectivity. To reduce influence ...

      Read Full Article
    16. Limbus-insertion distance of superior rectus in primary angle closure glaucoma: an anterior segment OCT study

      Limbus-insertion distance of superior rectus in primary angle closure glaucoma: an anterior segment OCT study

      Objective To compare the distance from the corneoscleral limbus to the insertion site of the superior rectus of primary angle-closure glaucoma (PACG) patients with normal controls and to identify potential characteristics associated with limbus-insertion distance. Design Cross-sectional study. Participants A total of 92 subjects (eyes) were enrolled in the study: 35 were nonglaucoma controls and 57 were PACG patients. Methods The limbus-insertion distance of the superior rectus was measured by anterior segment optical coherence tomography (AS-OCT) and intraoperative surgical caliper. The anterior chamber parameters were also measured using AS-OCT to identify potential characteristics associated with limbus-insertion distance. Results The limbus-insertion ...

      Read Full Article
    17. Effects of Valsalva Maneuver on Anterior Chamber Parameters and Choroidal Thickness in Healthy Chinese: An AS-OCT and SS-OCT Study

      Effects of Valsalva Maneuver on Anterior Chamber Parameters and Choroidal Thickness in Healthy Chinese: An AS-OCT and SS-OCT Study

      Purpose : This study concurrently evaluated the effects of the Valsalva maneuver (VM) on the anterior and posterior ocular biometric parameters in a healthy Chinese cohort. Methods : This prospective, cross-sectional study used anterior segment optical coherence tomography (AS-OCT) and swept-source optical coherence tomography (SS-OCT) to measure the anterior and posterior ocular biometric parameters before and during the VM. Sixty-three volunteers (126 eyes; 17 males and 46 females) were enrolled. The IOP, blood pressure (BP), and refractive error were recorded before and during a VM. Results : The mean IOP showed a statistically significant increase (from 13.86–14.25 mm Hg, P ...

      Read Full Article
    18. Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomograph

      Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomograph

      Purpose: The aim of the present study was to evaluate the effect of surgical peripheral iridectomy (SPI) on choroidal thickness in primary angle-closure suspect (PACS) eyes. Materials and Methods: This was a prospective observational case series of 30 subjects with PACS. Ocular biometry was performed before SPI (baseline) and then 1 week later. Choroid was imaged by enhanced depth imaging optical coherence tomography (EDI-OCT). The choroidal thickness of the subfoveal area at 1 and 3 mm diameter around the fovea was determined. Central anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL) were measured ...

      Read Full Article
    19. Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomography

      Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomography

      Purpose: The aim of the present study was to evaluate the effect of surgical peripheral iridectomy (SPI) on choroidal thickness in primary angle-closure suspect (PACS) eyes. Materials and Methods: This was a prospective observational case series of 30 subjects with PACS. Ocular biometry was performed before SPI (baseline) and then 1 week later. Choroid was imaged by enhanced depth imaging optical coherence tomography (EDI-OCT). The choroidal thickness of the subfoveal area at 1 and 3 mm diameter around the fovea was determined. Central anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL) were measured ...

      Read Full Article
    20. Swept-source optical coherence tomography imaging of macular retinal and choroidal structures in healthy eyes

      Swept-source optical coherence tomography imaging of macular retinal and choroidal structures in healthy eyes

      Background To report the thickness of the retina, retinal ganglion cell (RGC)-related layers, and choroid in healthy subjects using swept source optical coherence tomography (SS-OCT). Methods One hundred and forty-six healthy volunteers were consecutively recruited for this prospective observational study. Thickness of retina, RGC-related layers, and choroid in the standard early treatment of diabetic retinopathy study (ETDRS) grid were automatically measured using one SS-OCT (DRI OCT-1, Topcon, Japan). The IOL Master (Carl Zeiss Meditec, Germany) was used to measure axial length (AL). Results Thicknesses of the average macular ganglion cell complex (GCC) and ganglion cell-inner plexiform layer (GCIPL) were ...

      Read Full Article
    21. Anterior and Posterior Ocular Biometry in Healthy Chinese Subjects: Data Based on AS-OCT and SS-OCT

      Anterior and Posterior Ocular Biometry in Healthy Chinese Subjects: Data Based on AS-OCT and SS-OCT

      Background To measure the anterior and posterior ocular biometric characteristics concurrently and to determine the relationship between the iris and choroid in healthy Chinese subjects. Methods A total of 148 subjects (270 eyes) were enrolled in this cross-section study. The anterior and posterior ocular biometric characteristics were measured simultaneously by anterior segment optical coherence tomography (AS-OCT) and swept-source optical coherence tomography (SS-OCT). Results Compared with male eyes, female eyes had narrower anterior biometric parameters that presented with smaller anterior segment parameters [including anterior chamber depth (ACD), width (ACW), area (ACA), and volume (ACV); (all p<0.001)], narrower anterior chamber ...

      Read Full Article
    22. Enhanced depth imaging-optical coherence tomography of the choroid in moderate and severe primary angle-closure glaucoma

      Enhanced depth imaging-optical coherence tomography of the choroid in moderate and severe primary angle-closure glaucoma

      Purpose To compare the choroidal thickness (CT) in eyes with moderate and severe primary angle-closure glaucoma (PACG) with the eyes of healthy controls. Methods Fifty-nine patients (59 eyes) with PACG and 56 age-matched normal subjects underwent macular CT scanning using enhanced depth imaging–optical coherence tomography. The subjects with PACG were further classified as having moderate [−12 dB ≤ visual field mean deviation (VF-MD) ≤ −6 dB] or severe (VF-MD < −12 dB) glaucoma. The average CT of the PACG eyes at each location was compared to that of normal eyes. Results The CT was significantly increased in moderate and severe PACG eyes ...

      Read Full Article
    23. Choroidal thickness in the subtypes of angle-closure: an EDI-OCT study

      Choroidal thickness in the subtypes of angle-closure: an EDI-OCT study

      Purpose: To evaluate choroidal thickness (CT) in the subtypes of angle-closure (AC) disease compared with CT in a normal control. Methods: A total of 297 subjects (eyes) were enrolled in the study: 87 were non-glaucoma controls and 210 were AC Subtype eyes [primary AC suspect (PACS), 73 eyes; acute primary AC (APAC), 46 eyes; primary AC (PAC), 35 eyes; and primary AC glaucoma (PACG), 56 eyes]. Enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) was used to measure the macular CT in the subtypes of AC disease and in normal control subjects. The average CT was compared among the 5 ...

      Read Full Article
    24. Choroidal Thickness in Fellow Eyes of Patients with Acute Primary Angle-Closure Measured by Enhanced Depth Imaging Spectral-Domain Optical Coherence Tomography

      Choroidal Thickness in Fellow Eyes of Patients with Acute Primary Angle-Closure Measured by Enhanced Depth Imaging Spectral-Domain Optical Coherence Tomography

      PURPOSE: To evaluate choroidal thickness in the fellow eyes of patients with acute primary angle-closure (APAC) and to compare with normal controls. METHODS: The study group comprised 44 fellow eyes defined as primary angle-closure suspect (PACS) of 44 subjects who had experienced APAC and 43 eyes of 43 healthy volunteers. Using enhanced depth imaging optical coherence tomography (EDI-OCT), the peripapillary and macular choroidal thickness of the PACS eyes and the control eyes were measured and compared at each location or segment. Pearson correlation analysis and a multivariable regression model were used to evaluate the relationships between choroidal thickness and related ...

      Read Full Article
    1-24 of 24
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Topics in the News

    1. (20 articles) Sun Yat-Sen University
    2. (2 articles) Medical University of Vienna
    3. (2 articles) Soochow University
    4. (2 articles) The Chinese University of Hong Kong
    5. (2 articles) Chinese Academy of Sciences
    6. (2 articles) Topcon Medical Systems
    7. (2 articles) Carl Zeiss Meditec
    8. (1 articles) Shanghai Jiao Tong University
    9. (1 articles) University of Washington
    10. (1 articles) Heidelberg Engineering
  3. Popular Articles

  4. Picture Gallery

    Choroidal Thickness in Fellow Eyes of Patients with Acute Primary Angle-Closure Measured by Enhanced Depth Imaging Spectral-Domain Optical Coherence Tomography Choroidal thickness in the subtypes of angle-closure: an EDI-OCT study Enhanced depth imaging-optical coherence tomography of the choroid in moderate and severe primary angle-closure glaucoma Anterior and Posterior Ocular Biometry in Healthy Chinese Subjects: Data Based on AS-OCT and SS-OCT Swept-source optical coherence tomography imaging of macular retinal and choroidal structures in healthy eyes Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomography Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomograph Effects of Valsalva Maneuver on Anterior Chamber Parameters and Choroidal Thickness in Healthy Chinese: An AS-OCT and SS-OCT Study Limbus-insertion distance of superior rectus in primary angle closure glaucoma: an anterior segment OCT study A prospective case-control study comparing optical coherence tomography characteristics in neuromyelitis optica spectrum disorder- optic neuritis and idiopathic optic neuritis Post-Doctoral and Graduate Student Research Positions at the University of Illinois Urbana-Champaign Multiscale correlation of microvascular changes on optical coherence tomography angiography with retinal sensitivity in diabetic retinopathy