Effect of white-to-white corneal diameter on biomechanical indices assessed by Pentacam Scheimpflug corneal tomography and corneal visualization Scheimpflug technology

Ortho-k lenses fitting in patients with “non-typical” corneas

The Eye ◽

10.33791/2222-4408-2020-1-22-29 ◽

2020 ◽

Vol 22 (129) ◽

pp. 22-29

Author(s):

Svetlana Kravchuk ◽

Olga Zhabina

Keyword(s):

Correction Method ◽

Diameter Ratio ◽

Corneal Curvature ◽

Individual Approach ◽

Fitting In ◽

Corneal Diameter ◽

Clinical Cases

We described two clinical cases of ortho-k lenses fitting in patients with “non-typical” corneal curvature/diameter ratio. The main goal was to acknowledge effective and safe use of this myopia correction method in patients with corneal diameter greater than 11 mm. Individual approach to each patient is the key to a successful and safe ortho-k lenses fitting.

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

European Journal of Ophthalmology ◽

10.1177/1120672121997672 ◽

2021 ◽

pp. 112067212199767

Author(s):

Iva Krolo ◽

Aida Kasumović ◽

Ivana Radman ◽

Pavao Pavić

Keyword(s):

Case Report ◽

Alport Syndrome ◽

Contact Lenses ◽

Corneal Dystrophy ◽

Clinical Findings ◽

Cross Linking ◽

Posterior Polymorphous Corneal Dystrophy ◽

One Year ◽

Corneal Tomography

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. Case report: A 22-year-old male was referred for his initial corneal topography, after he was already prescribed with rigid gas-permeable contact lenses. Alport syndrome was diagnosed in his infancy and gene COL4A5 mutation was confirmed. Ophthalmological evaluation confirmed keratoconus. One-year follow-up showed a progression on his right eye and standard corneal cross-linking was performed. Stabilization of the disease marked by normalization in visual function and corneal tomography values was noticed 1 year after the procedure. Conclusions: When diagnosing ocular clinical findings of Alport syndrome, keratoconus should be considered. Standard corneal cross-linking protocol can halt its progression.

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Repeatability of automated measurements by a new anterior segment optical coherence tomographer and biometer and agreement with standard devices

Scientific Reports ◽

10.1038/s41598-020-79674-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Domenico Schiano-Lomoriello ◽

Kenneth J. Hoffer ◽

Irene Abicca ◽

Giacomo Savini

Keyword(s):

Intraclass Correlation ◽

Anterior Segment ◽

Consecutive Series ◽

Optical Coherence ◽

Limits Of Agreement ◽

Automated Measurements ◽

Deviation Coefficient ◽

Corneal Diameter ◽

High Repeatability ◽

Good Agreement

AbstractWe assess repeatability of automatic measurements of a new anterior segment optical coherence tomographer and biometer (ANTERION) and their agreement with those provided by an anterior segment-optical coherence tomography device combined with Placido-disk corneal topography (MS-39) and a validated optical biometer (IOLMaster 500). A consecutive series of patients underwent three measurements with ANTERION and one with MS-39. A subgroup of patients underwent biometry also with IOLMaster 500. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (COV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. Paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. Repeatability of ANTERION measurements was high, with ICC > 0.98 for all parameters except astigmatism (0.963); all parameters apart from those related to astigmatism revealed a COV < 1%. Repeatability of astigmatism improved when only eyes whose keratometric astigmatism was higher than 1.0 D were investigated. Most measurements by ANTERION and MS-39 showed good agreement. No significant differences were found between measurements by ANTERION and IOLMaster, but for corneal diameter. ANTERION revealed high repeatability of automatic measurements and good agreement with both MS-39 and IOLMaster for most parameters.

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White-to-white corneal diameter, pupil diameter, central corneal thickness and thinnest corneal thickness values of emmetropic subjects

Surgical and Radiologic Anatomy ◽

10.1007/s00276-011-0889-4 ◽

2011 ◽

Vol 34 (2) ◽

pp. 167-170 ◽

Cited By ~ 11

Author(s):

Juan A. Sanchis-Gimeno ◽

Daniel Sanchez-Zuriaga ◽

Francisco Martinez-Soriano

Keyword(s):

Central Corneal Thickness ◽

Pupil Diameter ◽

Corneal Thickness ◽

Corneal Diameter

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THE CORNEAL DIAMETER GAUGE

Journal of Refractive Surgery ◽

10.3928/1081-597x-19941101-19 ◽

1994 ◽

Vol 10 (6) ◽

pp. 663-663

Author(s):

Anonymous

Keyword(s):

Corneal Diameter

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Outcomes of a 320-degree intrastromal corneal ring segment implantation for keratoconus: Results of a 6-month follow-up

European Journal of Ophthalmology ◽

10.1177/1120672118818018 ◽

2018 ◽

Vol 30 (1) ◽

pp. 139-146 ◽

Cited By ~ 3

Author(s):

Guilherme Andrade do Nascimento Rocha ◽

Paulo Ferrara de Almeida Cunha ◽

Leonardo Torquetti Costa ◽

Luciene Barbosa de Sousa

Keyword(s):

Visual Acuity ◽

Spherical Equivalent ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Intrastromal Corneal Ring ◽

Corrected Distance Visual Acuity ◽

Ring Segment ◽

The Mean ◽

Corneal Tomography

Importance: This study shows that a newer long-arc length intrastromal corneal ring segment is efficient and safe for keratoconus treatment. Background: To evaluate visual, tomographic results and complications of a 320-degree intrastromal corneal ring segment implantation with the femtosecond laser for keratoconus treatment. Design: A prospective, nonrandomized, and interventional study. Participants: A total of 34 eyes of 31 patients diagnosed with keratoconus were enrolled. Methods: Patients were divided into two groups based on the strategy used for 320-degree intrastromal corneal ring segment thickness selection. In one group, this selection was based on spherical equivalent (SE group) and in the other on the mean asphericity (Q group). The uncorrected and corrected distance visual acuities, spherical equivalent, K1, K2, Km, Kmax, and mean asphericity ( Q) on corneal tomography were evaluated preoperatively and at 3 and 6 months postoperatively. For astigmatism improvement, we analyzed the corneal tomographic vectorial astigmatism change preoperatively and at 6 months postoperatively. The mean follow-up period was 6.63 ± 0.96 months. Results: The mean uncorrected distance visual acuity and corrected distance visual acuity improved with a significant spherical equivalent improvement ( p < 0.05), with no differences between the 320-degree intrastromal corneal ring segment groups. All corneal tomographic parameters improved significantly ( p < 0.05) between the preoperative and postoperative intervals, with a significant better performance when we used spherical equivalent for the 320-degree intrastromal corneal ring segment thickness selection. Finally, the mean vectorial corneal tomographic astigmatism significantly improved after 6 months, again with no differences between groups. Conclusion: This study suggests that implanting a 320-degree intrastromal corneal ring segment is a safe and effective procedure for treating patients with keratoconus. It also suggests that for thickness selection spherical equivalent is the better strategy.

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A New Pre-descemetic Corneal Ring (Neoring) in Deep Anterior Lamellar Keratoplasty for Moderate-Advanced Keratoconus: A Pilot 2-Year Long-Term Follow-Up Study

Frontiers in Medicine ◽

10.3389/fmed.2021.771365 ◽

2021 ◽

Vol 8 ◽

Author(s):

Belén Alfonso-Bartolozzi ◽

Carlos Lisa ◽

Luis Fernández-Vega-Cueto ◽

David Madrid-Costa ◽

José F. Alfonso

Keyword(s):

Spherical Aberration ◽

Lamellar Keratoplasty ◽

Deep Anterior Lamellar Keratoplasty ◽

Anterior Lamellar Keratoplasty ◽

Corrected Distance Visual Acuity ◽

Long Term Follow Up ◽

The Mean ◽

Corneal Tomography

Purpose: To assess the outcomes of implanting a new polymethylmethacrylate (PMMA) ring (Neoring; AJL Ophthalmic) in pre-descemet deep anterior lamellar keratoplasty (PD-DALK) procedure for moderate-advanced keratoconus.Methods: This prospective study included 10 eyes of 10 patients with moderate-advanced keratoconus who underwent PD-DALK with Neoring implantation. Neoring was implanted in a pre-descemetic pocket. The post-operative examination included refraction, corrected distance visual acuity (CDVA), corneal tomography, and endothelial cell density (ECD). The root mean squares (RMSs) for coma-like aberrations and spherical aberration were evaluated for a pupil size of 4.5 mm. The junctional graft (Tg) and host (Th) thicknesses were measured. The post-operative follow-up was 24 months.Results: Post-operative CDVA was 0.82 ± 0.14 (decimal scale), 100% of the eyes achieved a CDVA of 0.7 (decimal scale). The refractive cylinder was −2.86 ± 1.65 2-years after surgery. No eyes had a post-operative refractive cylinder ≥5.00 D and in five eyes (50%), it was ≤2.50 D. At the last visit, the mean keratometry was 45.64 ± 1.96 D, the RMS for coma-like aberrations was 0.30 ± 0.15 μm and spherical aberration was 0.22 ± 0.09. The mean ECD remains without changes over the follow-up (P = 0.07). At the last visit, Tg and Th were 679.9 ± 39.0 and 634.8 ± 41.2 μm, respectively. The thickness of the complex (host-Neoring) was 740.6 ± 35.6 μm. In all cases, this thickness was thicker than Tg.Conclusion: The results of this study suggest that PD-DALK along Neoring implantation is a viable, effective, and safe option to optimize the post-operative results for moderate-severe keratoconus.

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