997 results match your criteria Corneal Topography and Imaging

Agreement of Anterior Segment Parameters Between Schiempflug Topography and Swept-Source Optic Coherence Based Optic Biometry in Keratoconus and Healthy Subjects.

Eye Contact Lens 2021 Mar 31. Epub 2021 Mar 31.

Department of Ophthalmology (H.G., İ.A., S. Kaya, S.S., A.C.Ç., K.S., V.G.), Trakya University of Medicine, Edirne, Turkey; and Department of Biostatistics and Medical Informatics (S. Korkmaz), Trakya University of Medicine, Edirne, Turkey.

Purpose: The aim of this study is to compare anterior segment parameters, including corneal thickness (CCT), keratometry and anterior chamber depth (ACD), and white to white corneal diameter (WTW), obtained by Pentacam Schiempflug imaging and intraocular lens (IOL) Master 700 swept-source optic coherence tomography biometry in keratoconus patients and healthy subjects.

Methods: This prospective cross-sectional instrument agreement analysis includes 88 eyes of 50 keratoconus patients and 87 eyes of 50 healthy subjects. Biometry was performed using IOL Master 700, and topography was performed using Pentacam. Read More

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Automated Keratoconus Detection by 3D Corneal Images Reconstruction.

Sensors (Basel) 2021 Mar 26;21(7). Epub 2021 Mar 26.

Department of Information Systems, College of Computer and Information Sciences, Princess Nourah bint Abdulrahman University, Riyadh 11351, Saudi Arabia.

This paper presents a technique for the detection of keratoconus via the construction of a 3D eye images from 2D frontal and lateral eye images. Keratoconus is a disease that affects the cornea. Normal case eyes have a round-shaped cornea, while patients who suffer from keratoconus have a cone-shaped cornea. Read More

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Efficacy of progressive thickness intrastromal corneal ring segments in the treatment of duck phenotype keratoconus.

Eur J Ophthalmol 2021 Mar 16:11206721211001722. Epub 2021 Mar 16.

Muscat Eye Laser Center, Muscat, Shatti Al Qurum, Sultanate of Oman.

Purpose: To evaluate clinical outcomes in patients with asymmetric duck phenotype keratoconus implanted with asymmetric progressive thickness intrastromal corneal ring segments (PT-ICRS, Keraring AS, Mediphacos, Belo Horizonte, Brazil), and to demonstrate improved visual acuity and symmetry in corneal flattening.

Methods: This single-center, retrospective, observational study evaluated the clinical outcomes at 1, 3, and 6 months after implantation of PT-ICRS in patients with duck phenotype keratoconus. After creating the intrastromal tunnel with a femtosecond laser, one 160-degree arc length PT-ICRS, either 150/250 µm or 200/300 µm, was implanted. Read More

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Impact of COVID-19 on keratoconus patients waiting for corneal cross linking.

Eur J Ophthalmol 2021 Mar 15:11206721211001315. Epub 2021 Mar 15.

Department of Ophthalmology, Royal Liverpool University Hospital, Liverpool, UK.

Purpose: Royal College of Ophthalmologist recent guidance recommended delaying cross-linking services during the COVID-19 pandemic. This study investigates the effects of such delays in the delivery of cross-linking services in patients with keratoconus progression.

Methods: Retrospective observational study of 46 patients with keratoconus progression, whose cross-linking was delayed due to the COVID-19 pandemic. Read More

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Corneal cross-linking for treatment of progressive keratoconus in a patient with Alport syndrome: A case report.

Eur J Ophthalmol 2021 Feb 25:1120672121997672. Epub 2021 Feb 25.

School of Medicine, University of Zagreb, Zagreb, Croatia.

Purpose: Ocular features of Alport syndrome include anterior lenticonus, posterior polymorphous corneal dystrophy, and fleck-and-dot retinopathy in most cases. Keratoconus in such patients has been rarely mentioned in previous studies. To our knowledge, this is the first report of corneal cross-linking for halting the progression of keratoconus in a patient with Alport syndrome. Read More

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February 2021

Keratoconus Features on Corneal Higher-Order Aberration Ablation Maps: Proof-of-Concept of a New Diagnostic Modality.

Clin Ophthalmol 2021 16;15:623-633. Epub 2021 Feb 16.

LASIK MD, Montreal, QC, Canada.

Purpose: To assess the potential application of corneal higher-order aberration (HOA) excimer ablation map imaging in identifying reproducible keratoconus (KC) features and to explore if newly derived map metrics correlate to Pentacam KC indices.

Methods: Case series of 12 eyes with KC ≥ grade 2. Topolyzer Vario corneal imaging with its resultant HOA ablation map islands were analyzed for their centroid, distance from center, angular position, orientation, sphericity, diameter, area, and maximal ablation depth. Read More

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February 2021

The effects of pharmacological accommodation and cycloplegia on axial length and choroidal thickness.

Arq Bras Oftalmol 2021 Mar-Apr;84(2):107-112

Ophthalmology Department, Pamukkale University, Denizli, Turkey.

Purpose: To investigate the effects of pharmacological accommodation and cycloplegia on ocular measurements.

Methods: Thirty-three healthy subjects [mean (±SD) age, 32.97 (±5. Read More

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Correlation between Corneal Topographic Patterns and Refractive Status of the Eye in an Adult Iranian Population: Tehran Study.

J Curr Ophthalmol 2020 Oct-Dec;32(4):349-354. Epub 2020 Dec 12.

Digestive Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: To evaluate the corneal topographic patterns in an adult Iranian population and investigate its correlation with the refractive status of the eye.

Methods: In a cross-sectional study named "Tehran Study," 1023 samples were selected by the cluster sampling method from the downtown area of Tehran. Eight hundred and forty-nine adults aged over 15 years participated. Read More

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December 2020

Topographic, elevation, and keratoconus indices for diagnosis of keratoconus by a combined Placido and Scheimpflug topography system.

Eur J Ophthalmol 2021 Feb 7:1120672121991725. Epub 2021 Feb 7.

Faculty of Medicine, Ain Shams University, Cairo, Egypt.

Purpose: To determine the accuracy of various corneal parameters in keratoconus diagnosis using Scheimpflug camera combined with Placido disk corneal topography (Sirius, CSO).

Methods: One hundred and fifteen keratoconic eyes (group1) and a 111 normal eyes (group2) were assessed prospectively between March 2018 and July 2019 for: corneal keratometric indices (K1, K2, sim K, apex curvature) at different corneal rings of both corneal surfaces, central corneal thickness (CCT), thinnest corneal thickness (TL), corneal asphericity (Q), elevation at thinnest point, root mean square (RMS), and root mean square per area (RMS/A) in spherical, aspheric and aspherotoric reference for both corneal surfaces and keratoconus summary parameters; surface asymmetry index of front and back (SIf, SIb respectively), elevation at keratoconus vertex front and back (KVf, KVb respectively), Baiocchi Calossi Versaci front and back index (BCVf, BCVb) and its vector summation (BCV) and convergence radius and cutoff value for each was calculated.

Results: All studied indices were significantly different between the two groups. Read More

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February 2021

Defining inclusion criteria and endpoints for clinical trials: a prospective cross-sectional study in CRB1-associated retinal dystrophies.

Acta Ophthalmol 2021 May 2;99(3):e402-e414. Epub 2021 Feb 2.

Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands.

Purpose: To investigate the retinal structure and function in patients with CRB1-associated retinal dystrophies (RD) and to explore potential clinical endpoints.

Methods: In this prospective cross-sectional study, 22 patients with genetically confirmed CRB1-RD (aged 6-74 years), and who had a decimal best-corrected visual acuity (BCVA) ≥ 0.05 at the last visit, were studied clinically with ETDRS BCVA, corneal topography, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence, Goldmann visual field (VF), microperimetry, full-field electroretinography (ERG) and full-field stimulus testing (FST). Read More

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Sensitivity and Specificity of Belin Ambrosio Enhanced Ectasia Display in Early Diagnosis of Keratoconus.

J Ophthalmol 2020 9;2020:7625659. Epub 2020 Dec 9.

Department of Ophthalmology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

Purpose: Early diagnosis of keratoconus disease (KCN) is the first priority in the preoperative evaluations of refractive surgery (RS).The aim of this study was to investigate the correlation between findings of Belin Ambrosio enhanced ectasia display (BAD) software and conventional corneal imaging (Orbscan and topography) in the early diagnosis of KCN.

Methods: For conducting this cross-sectional study, a total of 1000 eyes were selected from 500 patients that underwent the myopic photorefractive keratectomy surgery and were compared in four study groups during the years 2017-2018. Read More

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December 2020

Influence of upper blepharoplasty on intraocular lens calculation.

Arq Bras Oftalmol 2021 Jan-Feb;84(1):11-16

Hospital Oftalmológico de Sorocaba, Sorocaba, Brazil.

Purpose: To determine the effect of upper blepharoplasty on corneal topography and intraocular lens power calculation using Galilei and IOLMaster.

Methods: Thirty patients submitted to upper blepharoplasty from May 2014 to March 2017 at the Hospital Oftalmológico de Sorocaba (São Paulo, Brazil) were included in this observational case series. All patients underwent imaging sessions with Galilei and IOLMaster preoperatively (baseline) and at 1 and 6 months postoperatively. Read More

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February 2021

[Comparison of corneal refractive power and astigmatism measured by the new anterior segment optical coherence tomographic device and Scheimpflug imaging device in age-related cataract patients].

Zhonghua Yan Ke Za Zhi 2021 Jan;57(1):48-55

Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin International Joint Research and Development Centre of Ophthalmology and Vision Science, Tianjin 300384, China.

To compare the difference and agreement of corneal refractive power and astigmatism measured by the new swept-source anterior segment optical coherence tomography (SS-AS-OCT) device (CASIA2) and Scheimpflug imaging device (Pentacam) in age-related cataract patients. In this cross-sectional study, 112 eyes of 112 patients with age-related cataract were examined before phacoemulsification in the Tianjin Medical University Eye Hospital from April to May 2020. The steep keratometry (Ks), flat keratometry (Kf), mean keratometry (Km), degree and axis of astigmatism of the corneal anterior and posterior surfaces and the total cornea were recorded. Read More

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January 2021

Detection of refractive photokeratectomy traces during eye banking: impossible with organ culture but possible with an active storage machine: case report.

Cell Tissue Bank 2021 Jan 4. Epub 2021 Jan 4.

Laboratory for Corneal Graft Biology, engineering and imaging (BiiGC, EA2521), Faculty of Medicine, University Jean Monnet, Health Innovation Campus, 10 rue de la marandière, F-42055, Saint-Etienne, France.

The detection of corneas operated on for refractive surgery [LASIK or photorefractive keratectomy (PRK)] will become a major concern for eye banks in the coming years because this surgery is often forgotten during the interview with the deceased's relatives. We present here 2 corneas operated on with PKR and stored successively in organ culture (OC) and in the active storage machine (ASM) that restores intraocular pressure, restores the cornea to its original shape, respects transparency and incorporates non-invasive controls. The 2 corneas of a 49-year-old donor operated 17 years earlier by PRK for -2 and -3 diopters myopia were stored in OC for 14 days and then placed in ASM for 48 h. Read More

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January 2021

Topographic properties of the cornea in welders.

Eur J Ophthalmol 2020 Dec 6:1120672120974293. Epub 2020 Dec 6.

Department of Medical Surgical Nursing, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Purpose: The aim of the present study was to evaluate the topographic status of the welders' corneas.

Methods: In this historical cohort, a group of welders (with at least 5 years' experience in welding) and a control group were assessed and compared. Lack of exposure to welding for 3 months or more was considered an exclusion criterion. Read More

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December 2020

Validity of percentage tissue altered as a screening formula for post laser-assisted keratomileusis ectasia in Indian eyes.

Indian J Ophthalmol 2020 Dec;68(12):2995-2997

M. M. Joshi Eye Institute, Hubli, Karnataka, India.

Purpose: To calculate a modified percentage tissue altered (mPTA) in post laser-assisted in-situ keratomileusis (LASIK) eyes and to validate its role as an independent factor to evaluate ectasia in the Indian population.

Methods: A total of 333 consecutive eyes with normal preoperative corneal topography by combined placido and scheimpflug imaging-based topography system (SIRIUS) who underwent LASIK using a microkeratome between 2011 and 2014 at a tertiary level teaching hospital in south India, were retrospectively analyzed. Preoperatively patient's refraction, flap thickness (FT), ablation depth (AD), residual stromal bed (RSB), and thinnest corneal thickness (TCT) were recorded. Read More

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December 2020

Advanced epithelial mapping for refractive surgery.

Indian J Ophthalmol 2020 Dec;68(12):2819-2830

Department of Cornea and Refractive Surgery,, Narayana Nethralaya, Bengaluru, India.

One of the leading challenges in refractive surgery today is the presence of underlying subclinical early-stage keratoconus (KC), which can lead to iatrogenic post laser in situ keratomileusis ectasia. Timely detection of this condition could aid the refractive surgeons in better decision-making. This includes being able to defer refractive surgery in subclinical cases as well as providing treatment for the same in the form of appropriate corneal collagen crosslinking treatments. Read More

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December 2020

Topography-guided treatment in regular and irregular corneas.

Indian J Ophthalmol 2020 Dec;68(12):2699-2704

The Eye Foundation, Coimbatore, Tamil Nadu, India.

Over the last decade, refractive surgery has been revolutionized by advancements in ablation profiles, available for the treatment of both regular and irregular corneas. Advances in corneal imaging have helped highlight the presence of higher-order aberrations, the correction of which could result in a better quality of vision. Topographic measurements being static are more repeatable and pupil independent and therefore provide the ideal platform for correction of both lower and higher-order aberrations and could result in improved visual quality even in patients with seemingly regular corneas. Read More

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December 2020

A singular case of iatrogenic gas-filled double anterior chamber after DALK.

Eur J Ophthalmol 2020 Nov 20:1120672120973610. Epub 2020 Nov 20.

Department of Neuroscience, Psychology, Pharmacology and Child Health, Eye Clinic, University of Florence, Florence, Italy.

Aim: To present a case of double anterior chamber after DALK and its surgical management.

Case Description: A 67-year-old healthy woman underwent deep anterior lamellar keratoplasty (DALK) in her right eye for keratoconus with the big-bubble technique. About 7 days after surgery a partial detachment of the Descemet membrane from the posterior corneal stroma was revealed using AS-OCT (double anterior chamber appearance). Read More

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November 2020

Comparison of variables measured with a Scheimpflug device for evaluation of progression and detection of keratoconus.

Sci Rep 2020 11 9;10(1):19308. Epub 2020 Nov 9.

Department of Ophthalmology, Ludwig-Maximilians University, Munich, Germany.

Keratoconus is a progressive ectatic corneal disorder, which can result in severe visual impairment. The new ABCD keratoconus classification system allows differentiated description of the disease. Aim of the study was to evaluate the components of this novel staging system (ARC, PRC, thinnest pachymetry) as well as topometric indices, deviation of normality indices, and other parameters in terms of repeatability and reliability. Read More

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November 2020

Excimer laser-assisted phototherapeutic keratectomies combined to EDTA chelation for the treatment of calcific band keratopathy.

Eur J Ophthalmol 2020 Nov 5:1120672120969033. Epub 2020 Nov 5.

Department of Sense Organs, Eye Clinic, University "La Sapienza", Rome, Italy.

Introduction: Calcific band keratopathy (CBK) is a relatively common chronic corneal degeneration and various forms of treatment are mentioned in the literature.

Cases Description: Two patients (89 and 37 yo, respectively) affected by diffuse long-standing CBK in one eye and complaining of ocular pain, foreign body sensation and decreased visual acuity are reported. An ethylenediaminetetraacetic acid (EDTA) application on the ocular surface was performed associated with a customized no-touch transepithelial phototherapeutic corneal remodeling in one patient and a standard phototherapeutic keratectomy (PTK) in the second patient. Read More

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November 2020

Reduced fluence corneal cross-linking in mild to moderate keratoconus: One year-follow-up.

Eur J Ophthalmol 2020 Oct 23:1120672120966560. Epub 2020 Oct 23.

Department of Ophthalmology, Geneva University Hospitals, Geneva, Switzerland.

Purpose: To evaluate the safety and efficacy of reduced fluence CXL (lower dose of UV-A irradiation) in mild to moderate keratoconus.

Setting: Farabi Eye Hospital, Tehran, Iran.

Design: Non-randomized prospective comparative interventional case series. Read More

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October 2020

The corneoscleral shape in Marfan syndrome.

Acta Ophthalmol 2020 Sep 30. Epub 2020 Sep 30.

Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium.

Purpose: To investigate the corneoscleral shape in Marfan syndrome (MFS) patients.

Methods: Thirty eyes of 15 participants with molecularly proven MFS were included in this prospective, cross-sectional study. Optical biometry, Scheimpflug imaging, and corneoscleral topography (Eye Surface Profiler) were performed in all patients. Read More

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September 2020

Three-Dimensional Morphogeometric and Volumetric Characterization of Cornea in Pediatric Patients With Early Keratoconus.

Am J Ophthalmol 2021 02 21;222:102-111. Epub 2020 Sep 21.

Department of Research and Development, VISSUM, Alicante, Spain; Cornea, Cataract and Refractive Surgery Department, VISSUM, Alicante, Spain; Division of Ophthalmology, Department of Pathology and Surgery, Faculty of Medicine, Miguel Hernández University, Alicante, Spain. Electronic address:

Purpose: To present morphogeometric and volumetric characteristics of the cornea and its diagnostic value in pediatric patients with keratoconus (KC) using 3-dimensional (3-D) corneal modeling.

Design: Cross-sectional study.

Methods: This single-center (VISSUM Innovation, Alicante, Spain) study comprised 49 eyes of 49 pediatric patients (age ≤16 years) with KC and 31 eyes of 31 healthy pediatric controls. Read More

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February 2021

Corneoscleral Topography Measured with Fourier-based Profilometry and Scheimpflug Imaging.

Optom Vis Sci 2020 09;97(9):766-774

Ophthalmic Research Group, Life and Health Sciences, Aston University, Birmingham, United Kingdom.

Significance: Precise measurement of corneoscleral topography makes a valuable contribution to the understanding of anterior eye anatomy and supports the fitting process of contact lenses. Sagittal height data, determined by newer noninvasive techniques, are particularly useful for initial scleral lens selection.

Purpose: The purpose of this study was to investigate the agreement and repeatability of Fourier-based profilometry and Scheimpflug imaging, in the measurement of sagittal height and toricity of the corneoscleral region. Read More

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September 2020

Utility of distant indirect ophthalmoscopy as screening tool in a case of pellucid marginal degeneration.

BMJ Case Rep 2020 Sep 9;13(9). Epub 2020 Sep 9.

Ophthalmology, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, Delhi, India.

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September 2020

[Characteristics of corneal topography in parents of keratoconus patients].

J Li L L Jing X L Du

Zhonghua Yan Ke Za Zhi 2020 Jun;56(6):456-464

Qingdao Eye Hospital Affiliated to Shandong First Medical University, State Key Laboratory Cultivation Base,Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao 266071, China.

To investigate the corneal topographic characteristics of the parents of patients with keratoconus (KC) and the correlation with their offspring. Case-control study. Twenty-six patients (49 eyes) with KC, who were 15 males and 11 females, and (18. Read More

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Intrastromal corneal ring segment implantation in paracentral keratoconus with perpendicular topographic astigmatism and comatic axis.

Eur J Ophthalmol 2020 Aug 24:1120672120952346. Epub 2020 Aug 24.

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

Purpose: To evaluate the outcomes of implanting intrastromal corneal ring segment (ICRS) using two different strategies in a specific paracentral keratoconus phenotype.

Methods: Eighty-nine eyes with paracentral keratoconus with perpendicular topographic astigmatism and comatic axes were evaluated before and after implanting a 150° arc-length ICRS. Patients were divided into two groups according to the axis where the ICRS was implanted: Group I: comatic axis and Group II: flat topographic axis. Read More

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