Questo articolo propone una revisione sistematica che fornisce un utile sommario sulle possibili alterazioni della trasparenza corneale, concentrandosi in particolar modo sulla sua valutazione, soggettiva ed oggettiva, nei portatori di lenti a contatto. Negli ultimi anni sono stati introdotti nella …
Purpose To compare and analyze the interchangeability of three measuring systems, each based on a different technique, for central corneal thickness (CCT) analysis. Methods CCT measurements were measured using optical coherence tomography (OCT), non-contact specular microscopy (NCSM), and ultrasonic pachymetry...
Purpose To determine the reliability of corneal endothelial cell density (ECD) obtained by automated specular microscopy versus that of validated manual methods and factors that predict such reliability. Methods Sharp central images from 94 control and 106 glaucomatous eyes were...
Key Points Question Can binocular optical coherence tomography (OCT) be used to measure the size of strabismus? Findings This study included 15 participants with strabismus and 15 healthy volunteers. In participants with strabismus, binocular OCT imaging correctly revealed the type and direction...
Abstract Purpose: To map the corneal epithelium using a map measuring 9 mm in diameter and view the effects of age, sex, and axial length. Additionally, we wanted to demonstrate the reproducibility of this technique. Methods: We calculated the epithelial thickness in...
Abstract Purpose To evaluate the differences in corneo-scleral topographic profile between healthy and keratoconus eyes, and their potential diagnostic ability for keratoconus detection. Methods Prospective comparative study including 21 keratoconic eyes (11 patients) and 88 healthy eyes (88 patients). In...
LINK PER SCARICARE APP ANDROID LINK PER SCARICARE APP IPHONE AV Converter – APP Punti tipografici (corpo tipografico): Unità usata in campo tipografico e nel word processing per specificare la dimensione di un carattere. Un punto tipografico equivale ad 1/72 …
Purpose To evaluate the repeatability of automatic measurements by a new anterior segment optical coherence tomographer (AS-OCT) combined with Placido topography and their agreement with those provided by 2 rotating Scheimpflug cameras. Setting G.B. Bietti Foundation IRCCS, Rome, Italy. Design...
SIGNIFICANCE The authors analyze factors influencing bivariate contour ellipse area (BCEA) in healthy and pathologic eyes and how such factors may affect isolated (static BCEA) or microperimetric fixation (dynamic BCEA). They conclude that aging increases both dynamic BCEA and examination time,...
Purpose: To evaluate a new method of calculation of total corneal astigmatism based on Gaussian optics and the power design of a spherocylindrical lens (C) in the healthy eye and to compare it with keratometric (K) and power vector (PV) methods. Methods: A total of 92...
Purpose To find differences in epithelial thickness (ET) maps of eyes with keratoconus (KC) and healthy eyes. Design Institutional cross-sectional study. Methods In this study 40 keratoconic eyes and 76 healthy eyes were scanned using a custom-built ultrahigh-resolution optical coherence …
Objectives: To investigate the interexaminer reliability of meibography evaluation and the impact of eyelid selection for the procedure. Methods: Meibography images of 30 subjects’ right eye, including both lids, were evaluated by three clinicians. Meibomian gland (MG) dropout was noted with respect...
Purpose: To determine the effect of cyclopentolate, tropicamide, and artificial tear drops on higher-order aberrations (HOAs) in normal eyes with OPD-Scan III (Nidek Inc., Tokyo, Japan). Methods: In this study, 189 eyes of individuals aged 20 to 35 years were selected as...
Purpose: To investigate the corneal densitometry in subclinical keratoconus with normal elevation and pachymetric parameters. Methods: Patients with clinical keratoconus in one eye and subclinical keratoconus in the fellow eye were identified. The study group was selected from patients with subclinical keratoconus...
Purpose: To assess the correlation between the scleral shape and corneal astigmatism. Methods: Twenty-two participants (11 nonastigmatic and 11 astigmatic) aged from 19 to 36 years and with no previous ocular surgeries were included in this study. Three-dimensional (3D) corneoscleral maps from...
Punti Chiave : Si è osservata la variazione di densità della cornea attraverso la Scheimpflug Camera in soggetti con cheratocono subclinico (senza variazione di forma anteriore e di spessore della cornea) E' stata misurata una differenza di densità della cornea...
Abstract Background To assess the precision and agreement of measurements of higher order aberrations (HOAs) obtained with a ray tracing aberrometer (iTrace) and a Hartmann-Shack aberrometer (Topcon KR-1 W). Methods Prospective evaluation of the diagnostic test. Data from the right eyes...
To evaluate the contribution of fixational eye movements to dynamic aberration, 50 healthy eyes were examined with an original custom-built Shack-Hartmann aberrometer, running at a temporal frequency of 236Hz, with 22 lenslets across a 5mm pupil, synchronized with a 236Hz...
Abstract PURPOSE:To describe a method by which mapped corneal elevation data can be used for ray-tracing analysis of the effective corneal power. METHODS:Mapped elevation data of the front and back surface of the cornea exported by a clinical Scheimpflug camera...
Purpose: Corneal tomography is used to assess progression of keratoconus and to direct clinical decisions regarding corneal cross-linking. The purpose of this study was to analyze the variability of repeated Scheimpflug-tomography (Pentacam Classic; Oculus, Wetzlar, Germany) measurements of keratoconic eyes...
Abstract Coherence scanning interferometry (CSI) offers three-dimensional (3D) measurement of surface topography with high precision and accuracy. Defocus within the interferometric objective lens, however, is commonly present in CSI measurements and reduces both the resolving power of the imaging system...
ABSTRACT Corneal imaging is essential for diagnosing and management of a wide variety of ocular diseases. Corneal topography is used to characterize the shape of the cornea, specifically, the anterior surface of the cornea. Most corneal topographical systems are based...
Abstract PURPOSE:To determine the accuracy of the PlusoptiX A12 photoscreener (PlusoptiX, Inc., Atlanta, GA) in detecting amblyopia or ambylogenic risk factors in pediatric patients in Nebraska. METHODS:Using the PlusoptiX A12 photoscreener, data were collected from pediatric patients seen at a...
SIGNIFICANCE A corneal heat-transfer model is presented to quantify simultaneous measurements of fluorescein tear-breakup area (TBA) and ocular-surface temperature (OST). By accounting for disruption of the tear-film lipid layer (TFLL), we report evaporation rates through lipid-covered tear. The modified heat-transfer...
SIGNIFICANCE The proposed automated approach for estimating the quality of the tear film closes the gap between the manual and automated assessment, translating the high-speed videokeratoscopy technology from scientific laboratories to a clinical practice. PURPOSE To develop and test a...
Tradotto e adattato da Role of anterior segment optical coherence tomography in angle closure disease: a review Punti Chiave: la tomografia a coerenza ottica del segmento anteriore (AS- OCT) permette una valutazione affidabile dell’angolo irido-corneale nelle patologie da angolo stretto è un metodo oggettivo …
Abstract Background and Objectives Objective was to examine new findings regarding conjunctival/scleral shape mapped with a novel wide field elevation topography device and software, to propose a new classification system for scleral shape. Methods The Scleral Shape Study Group (SSSG)...
Tradotto e adattato da Advanced anterior segment imaging in keratoconus: a review Punti Chiave: tecniche sempre più sofisticate di acquisizione e analisi delle immagini permettono di diagnosticare precocemente il cheratocono, visualizzare le strutture corneali e le modifiche dovute all’evoluzione della patologia l’articolo analizza le opportunità...
Purpose: To determine the differences in the retinal sensitivities obtained by microperimetry with a single cross or a circular fixation target in normal individuals. Methods: Thirty-two eyes of 16 healthy volunteers (mean age 28.9±1.4 years, range 24–44 years) were studied. The retinal...
Abstract Purpose To determine the change and rate of change in central corneal thickness (CCT) and their determinants. Design Longitudinal observational population-based study. Methods 758 normal and 58 glaucomatous subjects underwent complete eye examination, with CCT measurements at two separate...
SIGNIFICANCE The cornea is a viscoelastic tissue with viscous and elastic properties. The information of corneal biomechanical changes in high myopia has implications for understanding the pathogenesis of high myopia and primary open angle glaucoma. However, the knowledge of corneal...
Purpose To evaluate the performance of waveform-derived variables in distinguishing normal, suspect, and keratoconic eyes. Setting Narayana Nethralaya Eye Hospital, Bangalore, India. Design Retrospective case series. Methods Scheimpflug tomography (Pentacam) and dynamic Scheimpflug analysis (Corvis ST) of 253 normal (253...
Abstract Purpose: This study investigated the anterior ocular anatomic origin of high-order aberration (HOA) components using optical coherence tomography and a Shack-Hartmann wavefront sensor. Methods: A customized system was built to simultaneously capture images of ocular wavefront aberrations and anterior ocular biometry....
Abstract Purpose To evaluate the intra-session repeatability of keratometric measurements obtained in healthy eyes with the Verion image-guided system (Alcon Laboratories Inc, Fort Worth, Texas, USA) as well as the interchangeability of such measurements with those obtained with an optical...
SIGNIFICANCE: Commercially available aberrometers are essential to clinical studies evaluating refractive error and image quality. The Discovery System (Innovative Visual Systems, Elmhurst, IL) is a promising clinical instrument that allows investigators to export aberration data for research and analysis purposes....
Hence manual keratometry should be taught as a historical perspective and also to demonstrate the principals of reflective (specular reflection) corneal curvature assessment. The insistence on the availability and/or use of keratometers in guidance from professional bodies and regulators should...
Purpose: To evaluate the reproducibility of Fourier domain anterior segment optical coherence tomography (RTVue) based on repeated measurements of corneal thickness (CT) and epithelial thickness (ET) and to test daytime-dependent changes of these parameters. Sorgente: Reproducibility and Daytime-Dependent Changes of...
Abstract Background Keratometry is a critical determinant of the post-operative refractive outcome. This study evaluates the comparability of keratometry measurements obtained using the Verion Optical Imaging system with devices used in current clinical practice. Sorgente: Assessment of corneal curvature using...
Purpose To assess the validity and repeatability of the Aston Halometer. Setting University clinic, United Kingdom. Design Prospective, repeated-measures experimental study. Methods The halometer comprises a bright light-emitting-diode (LED) glare source in the center of an iPad4. Letters subtending 0.21°...
To evaluate and compare (anterior and posterior) corneal parameters obtained by use of 3 corneal topography devices. Sorgente: Comparison of anterior and posterior topographic analysis between 3 imaging systems...
To compare area densitometry analysis using rotating Scheimpflug photography in quantifications of posterior capsule opacification (PCO) and surface light scattering with previous anterior-segment analyzer measurement. Sorgente: Area densitometry using rotating Scheimpflug photography for posterior capsule opacification and surface light scattering...
sorgente http://onlinelibrary.wiley.com/doi/10.1111/ceo.13082/abstract...
Meibomian glands secrete the oily layer of the tear film, which prevents excessive evaporation of tear fluid. Dysfunction of meibomian glands is not only one of the causes of evaporative dry eye but also one of the main causes of...
Objectives: To assess accuracy and repeatability of the CASIA swept-source optical coherence tomographer (SS-OCT) in measuring contact lens (CL) radii of curvature and thicknesses compared with verified CL parameters and to investigate intrasession and intersession repeatability of the CASIA SS-OCT...
Abstract The slit lamp enables a well-illuminated and magnified view of the eye. There have been previous imaging devices used for recording, however the quality of the stills and video is limited by cost. We present a relatively lower cost...
http://www.contactlensjournal.com/article/S1367-0484(16)30128-X/fulltext?rss=yes Abstract Purpose To assess whether short-term soft contact lens wear alters the anterior eye surface. Methods Twenty-two neophyte subjects wore soft contact lenses for a period of five hours. Topography based corneo-scleral limbal radius estimates were derived from height …
http://onlinelibrary.wiley.com/doi/10.1111/cxo.12546/abstract Abstract Background Measurement of tear film stability is commonly used to give an indication of tear film quality but a number of non-invasive techniques exists within the clinical setting. This study sought to compare three non-invasive tear film stability …
CONCLUSIONS: The Cirrus OCT and Sirius topographer showed good precision outcomes to measure the anterior segment of the eye. Nevertheless, clinical criteria are needed to judge whether these devices could be used interchangeably. http://www.healio.com/ophthalmology/journals/jrs/2016-11-32-11/{b4ecb20b-f7a8-42fb-a138-1567da049b1b}/precision-of-high-resolution-oct-for-anterior-chamber-measurement-agreement-with-scheimpflug-imaging...
http://journals.lww.com/claojournal/Abstract/publishahead/Comparision_of_Optical_Low_Coherence_Reflectometry.99400.aspx
https://www.osapublishing.org/boe/fulltext.cfm?uri=boe-8-2-918&id=357467 Articolo Open Access Abstract The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region …
un recente Lavoro italiano molto interessante: https://www.ncbi.nlm.nih.gov/pubmed/27571223
#optometria uso della lampada a fessura per imaging simile a OCT http://journals.lww.com/claojournal/Abstract/publishahead/Slitlamp_Photography_and_Videography_With_High.99567.aspx
Complete 360° circumferential gonioscopic optical coherence tomography imaging of the iridocorneal angle La gonioscopia è esame medico che consente la visualizzazione dell’angolo irido corneale nella porzione interna dell’occhio, area dove sono presenti le strutture di drenaggio dei fluidi intraoculari. E’ esame …
