To investigate the pattern of diurnal variations in axial length (AL), choroidal thickness, intraocular pressure (IOP), and ocular biometrics over 2 consecutive days.Measurements IOP were collected for 30 young adult subjects (15 myopes, 15 emmetropes) at 10 different times days. Five sets measurements each day approximately 3-hour intervals, with first measurement taken ~9 AM final PM.AL underwent significant variation (P < 0.0001) that was consistently observed across The longest AL...

Purpose: The purpose of this study was to examine the relationship between objectively measured ambient light exposure and longitudinal changes in axial eye growth childhood. Methods: A total 101 children (41 myopes 60 nonmyopes), 10 15 years age participated prospective observational study. Axial determined from measurements ocular optical biometry collected at four visits over an 18-month period. Each child's mean daily derived two periods (each 14 days long) objective a wrist-worn sensor....

We examined choroidal thickness (ChT) and its topographic variation across the posterior pole in myopic nonmyopic children.A total of 104 children aged 10 to 15 years (mean age, 13.1 ± 1.4 years) had ChT measured using enhanced depth imaging optical coherence tomography (OCT). Of these 40 were spherical equivalent, -2.4 1.5 diopters [D]) 63 (mean, +0.3 0.3 D). Two series 6 radial OCT line scans centered on fovea assessed for each child. Subfoveal a parafoveal zones over central mm determined...

Purpose.: To investigate the short-term influence of imposed monocular defocus on human optical axial length (the distance from anterior cornea to retinal pigment epithelium) and ocular biometrics. Methods.: Twenty-eight young adult subjects (14 myopes, 14 emmetropes) had eye biometrics measured before 30 60 minutes after exposure (right eye) defocus. Four different conditions were tested, each a separate day: control (no defocus), myopic (+3 D hyperopic (−3 diffuse (0.2 density Bangerter...

To objectively assess daily light exposure and physical activity levels in myopic emmetropic children.One hundred two children (41 myopes 61 emmetropes) aged 10 to 15 years old had simultaneous objective measures of ambient collected over a 2-week period during school term, using wrist-worn actigraphy device (Actiwatch 2). Measures visible illuminance were captured every 30 seconds, 24 hours day this period. Mean hourly for weekdays weekends examined. ensure that seasonal variations did not...

To investigate associations between the diurnal variation in a range of corneal parameters, including anterior and posterior topography, regional thickness.Fifteen subjects had their corneas measured using rotating Scheimpflug camera (Pentacam) every 3 to 7 h over 24-h period. Anterior axial curvature, pachymetry chamber depth were analyzed. The best fitting sphero-cylinder from average thickness for series different regions calculated. Measures intraocular pressure length also taken at each...

Purpose.: To examine longitudinal changes in choroidal thickness and axial length a population of children with range refractive errors. Methods.: One hundred one (41 myopes 60 nonmyopes) aged 10 to 15 years participated this prospective, observational study. For each child, 6-month measures (using enhanced depth imaging optical coherence tomography) ocular biometry were collected four times over an 18-month period. Linear mixed-models used the relationship between eye growth study Results.:...

We examined choroidal thickness (ChT) and its spatial distribution across the posterior pole in pediatric subjects with normal ocular health minimal refractive error.ChT was assessed using spectral domain optical coherence tomography (OCT) 194 children aged 4 to 12 years, spherical equivalent errors between +1.25 -0.50 diopters sphere (DS). A series of OCT scans were collected, imaging choroid along radial scan lines centered on fovea (each separated by 45°). Frame averaging used reduce...

To investigate the diurnal variation in axial length and anterior eye biometrics, while simultaneously measuring intraocular pressure (IOP) with dynamic contour tonometry human subjects.Fifteen young adult near-emmetropic subjects had length, biometrics (central corneal thickness chamber dimensions), IOP measured at six different times across a 24-hour measurement period. Repeated-measures ANOVA sine curve fitting were used to analyze rhythms each parameter.Axial was found undergo...

The assessment of choroidal thickness from optical coherence tomography (OCT) images the human choroid is an important clinical and research task, since it provides valuable information regarding eye's normal anatomy physiology, changes associated with various eye diseases development refractive error. Due to time consuming subjective nature manual image analysis, there a need for reliable objective automated methods segmentation derive measures. However, detection two boundaries which...

Purpose. To characterize the changes occurring in choroidal thickness (ChT) across posterior pole during accommodation using enhanced-depth imaging optical coherence tomography (OCT). Methods. Forty participants (mean age 21 ± 2 years) had measures of ChT and ocular biometry taken to 0, 3, 6 diopter (D) stimuli, with Spectralis OCT Lenstar biometer. A Badal optometer cold mirror system was mounted on both instruments, allowing measurement collection while subjects viewed an external fixation...

Abstract The analysis of the choroid in eye is crucial for our understanding a range ocular diseases and physiological processes. Optical coherence tomography (OCT) imaging provides ability to capture highly detailed cross-sectional images yet only very limited number commercial OCT instruments provide methods automatic segmentation choroidal tissue. Manual annotation boundaries often performed but this impractical due lengthy time taken analyse large volumes images. Therefore, there...

Purpose To investigate the influence of monocular hyperopic defocus on normal diurnal rhythms in axial length and choroidal thickness young adults. Methods A series measurements (collected at ∼3 hourly intervals, with first measurement ∼9 am final pm) were obtained for 15 emmetropic adults over three consecutive days. The natural (day 1, no defocus), 2, −2.00 DS spectacle lens right eye), recovery from any induced changes 3, defocus) examined. Results Both underwent significant each days (p...

The manual segmentation of individual retinal layers within optical coherence tomography (OCT) images is a time consuming task and prone to errors.The investigation into automatic methods that are both efficient accurate has seen variety proposed.In particular, recent machine learning approaches have focused on the use convolutional neural networks (CNNs).Traditionally applied sequential data, recurrent (RNNs) recently demonstrated success in area image analysis, primarily due their...

Deep learning strategies, particularly convolutional neural networks (CNNs), are especially suited to finding patterns in images and using those for image classification.The method is normally applied an patch assigns a class weight the patch; this has recently been used detect probability of retinal boundary locations OCT images, which subsequently segment graph-search approach.This paper examines effects number modifications CNN architecture with aim optimizing layer segmentation,...

Abstract There is a paucity of knowledge regarding the normal in-vivo thickness choroid beyond macula (~17°). In this study, choroidal 27 healthy young adults was examined across macular (the central 5 mm including fovea, parafovea, and perifovea) extra-macular (a 5–14 annulus near-periphery periphery) regions using wide-field optical coherence tomography, compared between emmetropes (n = 14) myopes 13). The progressively thinned parafovea (350 ± 86 µm) towards periphery (264 44 µm),...