International Journal of Keratoconus and Ectatic Corneal Diseases

Register      Login

Table of Content

2016 | January-April | Volume 5 | Issue 1

RESEARCH ARTICLE

Isaac Ramos, Marcella Q Salomão, Fernando F Correia

Corneal Deformation Response with Dynamic Ultra-high-speed Scheimpflug Imaging for Detecting Ectatic Corneas

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:5] [Pages No:1 - 5]

PDF  |  DOI: 10.5005/jp-journals-10025-1113  |  Open Access |  How to cite  | 

Abstract

Purpose

To test the ability of metrics derived from corneal response to noncontact tonometry (NCT) to distinguish between normal and ectatic cases.

Materials and methods

The prototype of CorVis ST (Oculus, Wetzlar, Germany) was used for assessing corneal biomechanical response using ultra-high-speed 8 mm horizontal Scheimpflug photography, taking 4,330 frames per second during NCT. Patients were stratified based on clinical data, including rotating Scheimpflug corneal tomography (Oculus Pentacam HR). Biomechanical data from one eye randomly selected of 177 patients with normal corneas (N) and from 79 patients with bilateral keratoconus (KC) were investigated. Group forme fruste keratoconus (FFKC) was composed of 20 eyes with normal topographic patterns from cases with ectasia detected in the fellow eye. Group keratoconus suspect (KCS) had 16 eyes from 16 patients with topographic patterns suspicious of KC but documented stability over 3 years and normal tomographic findings. A combination of deformation parameters using linear regression analysis (Prototype Factor 1, pF1) was created by the BrAIn (Brazilian Artificial Intelligence on Corneal Tomography and Biomechanics) study group in order to provide the best possible separation of KC and normals.

Results

Statistical significant differences were found for N × KC for several parameters, including first and second applanation times, deformation amplitude, and maximal concavity radius (Mann–Whitney, p < 0.001). However, the areas under the receiver operating characteristic curves (AUC) were lower than 0.90. The pF1 had AUC of 0.945 (IC 0.909–0.97; sensitivity = 87.3% and specificity = 89.3%). The pF1 had statistically significant differences between the ectatic (KC and FFKC) and nonectatic groups (N and KCS) (p < 0.05, Kruskall–Wallis Test with post hoc Dunn's test).

Conclusion

Corneal deformation response analysis by ultra- high-speed 8 mm horizontal Scheimpflug photography provides relevant data for distinguishing ectatic and nonectatic corneas but cannot be used independently to detect KC. This data may be integrated with corneal tomography data for enhancing sensitivity and specificity for screening ectasia.

How to cite this article

Salomão MQ, Correia FF, Ramos I, Luz A, Ambrósio R Jr. Corneal Deformation Response with Dynamic Ultra-high-speed Scheimpflug Imaging for Detecting Ectatic Corneas. Int J Kerat Ect Cor Dis 2016;5(1):1-5.

RESEARCH ARTICLE

Eye Rubbing, a Sine Qua Non for Keratoconus?

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:7] [Pages No:6 - 12]

PDF  |  DOI: 10.5005/jp-journals-10025-1114  |  Open Access |  How to cite  | 

Abstract

How to cite this article

Gatinel D. Eye Rubbing, a Sine Qua Non for Keratoconus? Int J Kerat Ect Cor Dis 2016;5(1):6-12.

RESEARCH ARTICLE

Shiji Ummar

Corneal Collagen Cross-linking in Infective Keratitis

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:4] [Pages No:13 - 16]

PDF  |  DOI: 10.5005/jp-journals-10025-1115  |  Open Access |  How to cite  | 

Abstract

Purpose of review

To summarize the current understanding of effects of cross-linking (CXL) in infective keratitis based on available evidence.

Method of literature search

A PubMed search was conducted with combinations not limited to the following search terms: corneal collagen CXL, riboflavin, ultraviolet A, keratoconus, microbial keratitis, fungal keratitis, bacterial keratitis, Acantha-moeba keratitis. A review of the search results was performed and relevant articles to the topic were included.

Summary

Most of the published literature showed promising results in treatment of infectious keratitis by corneal collagen CXL using photoactivated riboflavin as an adjuvant therapy but with questionable efficacy in deep keratitis due to slow-growing organisms.

How to cite this article

Ummar S, Farrag AN. Corneal Collagen Cross-linking in Infective Keratitis. Int J Kerat Ect Cor Dis 2016;5(1):13-16.

RESEARCH ARTICLE

Suruchi Gupta

Implantable Contact Lenses in Keratoconus

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:4] [Pages No:17 - 20]

PDF  |  DOI: 10.5005/jp-journals-10025-1116  |  Open Access |  How to cite  | 

Abstract

How to cite this article

Gupta S. Implantable Contact Lenses in Keratoconus. Int J Kerat Ect Cor Dis 2016;5(1):17-20.

RESEARCH ARTICLE

Paolo Vinciguerra, Raffaele Piscopo, Fabrizio Camesasca, Riccardo Vinciguerra

Progression in Keratoconus

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:11] [Pages No:21 - 31]

PDF  |  DOI: 10.5005/jp-journals-10025-1117  |  Open Access |  How to cite  | 

Abstract

How to cite this article

Vinciguerra P, Piscopo R, Camesasca F, Vinciguerra R. Progression in Keratoconus. Int J Kerat Ect Cor Dis 2016;5(1):21-31.

RESEARCH ARTICLE

José RC Reis, Alberto Diniz-Filho, Fábio M Rocha

Pathogenesis of Fixed Dilated Pupil (Urrets-Zavalía Syndrome) after Deep Lamellar Keratoplasty in Keratoconus

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:3] [Pages No:32 - 34]

PDF  |  DOI: 10.5005/jp-journals-10025-1118  |  Open Access |  How to cite  | 

Abstract

Purpose

To present a case series of patients that developed Urrets-Zavalia syndrome (UZS) after deep anterior lamellar keratoplasty (DALK) for treating keratoconus and discuss the mechanisms for the syndrome.

Materials and methods

Retrospective chart analysis of patients who developed UZS after DALK at the Cornea Unit, Hospital São Geraldo, Federal University of Minas Gerais.

Results

We present a series of 3 patients with features consistent with UZS, after undergoing DALK. Elevated intraocular pressure (IOP) was noted in the early postoperative period in 2 cases, despite the fact that the other case reported eye pain, headache, and nausea at the night after the surgery with undocumented IOP. Although at different extents, the pupil remained atrophic and dilated in all 3 eyes, and 2 of them developed anterior subcapsular cataract.

Conclusion

Iris ischemia resulting from occlusion of iris root vessels due to elevated IOP higher than diastolic blood pressure causes UZS. Elevated IOP should be monitored, especially in young patients with low diastolic blood pressure, in order to avoid the occurrence of the syndrome.

How to cite this article

Reis JRC, Diniz-Filho A, Rocha FM, Torquetti L. Pathogenesis of Fixed Dilated Pupil (Urrets-Zavalía Syndrome) after Deep Lamellar Keratoplasty in Keratoconus. Int J Kerat Ect Cor Dis 2016;5(1):32-34.

RESEARCH ARTICLE

Isaac Ramos, Gustavo Guerra, Vitor Buchmuller de Oliveira, Ivan Ferreira

Subclinical Keratoconus Detection in Identical Twins

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:5] [Pages No:35 - 39]

PDF  |  DOI: 10.5005/jp-journals-10025-1119  |  Open Access |  How to cite  | 

Abstract

Purpose

To report clinical keratoconus in only one eye of two identical female twins, along with subclinical disease in the fellow eyes, elaborating on the two-hit hypothesis of ectasia development, which relates to the combination of genetics and the impact of environment.

Methods

Case report and literature review.

Results

Two identical 48-year-old female twins were presented for clinical evaluation. Mild keratoconus was detected in the right eye of twin 1, characterized by classic slit-lamp findings (exacerbated corneal nerves and incomplete Fleisher's ring) and front surface curvature abnormalities, including asymmetry of the inferior–superior curvature at 6 mm (I–S value) of 2.78 D and a grade 1 Topographic Keratoconus Classification pattern. Topographic Keratoconus Classification was possible in the fellow eye of twin 1 (I–S value = 1.22 D) and negative in both eyes of twin 2 (I–S value = −0.46 OD and −0.13 OS). Ambrósio's Relational Thickness for the maximal progression meridian was 209 and 354 in twin 1 and 360 and 392 in twin 2 in the right and left eyes respectively. The final deviation value of the Belin–Ambrósio Enhanced Ectasia Display was 4.54 and 1.47 in twin 1 and 1.7 and 1.35 in twin 2.

Conclusion

Corneal tomography data provide a better representation of corneal genotype in detecting mild, subclinical, or forme fruste keratoconus in the fellow eyes with normal topography of these twins. These cases present high risk or susceptibility for ectasia progression if environmental factors are associated (second hit).

How to cite this article

Guerra G, de Oliveira VB, Ferreira I, Ramos I, Belin MW, Ambrósio R Jr. Subclinical Keratoconus Detection in Identical Twins. Int J Kerat Ect Cor Dis 2016;5(1):35-39.

RESEARCH ARTICLE

Bernardo Lopes, Marcella Q Salomão, Isaac C Ramos, Fernando Faria-Correia

Unilateral Ectasia characterized by Advanced Diagnostic Tests

[Year:2016] [Month:January-April] [Volume:5] [Number:1] [Pages:12] [Pages No:40 - 51]

PDF  |  DOI: 10.5005/jp-journals-10025-1120  |  Open Access |  How to cite  | 

Abstract

How to cite this article

Ramos IC, Reinstein DZ, Archer TJ, Gobbe M, Salomão MQ, Lopes B, Luz A, Faria-Correia F, Gatinel D, Belin MW, Ambrósio R Jr. Unilateral Ectasia characterized by Advanced Diagnostic Tests. Int J Kerat Ect Cor Dis 2016;5(1):40-51.

© Jaypee Brothers Medical Publishers (P) LTD.