Villavicencio OF, Gilani F, Henriquez MA, Izquierdo L Jr, Ambrósio RR Jr, Belin MW. Independent Population Validation of the Belin/Ambrósio Enhanced Ectasia Display:Implications for Keratoconus Studies and Screening. Int J Kerat Ect Cor Dis 2014;3(1):1-8.

To determine the prevalence of keratoconus (KC) in an Arab population in Israel.

Videokeratography was performed on volunteer students from the Academic Arab College of Education, in Haifa, Israel. All participants filled out a self-administered questionnaire to evaluate possible risk factors for KC. Univariate and multivariate analysis were performed.

Data of 314 participants were analyzed and a prevalence of (N = 10), 3.18% (95% CI, 1.2 to 5.1%) was found. The only significant factor (both in univariate and multivariate analysis) that was associated with KC was parental consanguinity (OR 5.10, p = 0.02). Druzes and Bedouins had a higher prevalence than Muslims and Christians. However, the differences were not significant possibly due to the small size of the sample.

The result of this study was similar to other studies conducted in the Middle East, which indicate a higher prevalence of KC than in western countries. It is also recommended that people who have consanguinity in their family should be topographically tested to detect the early stages of KC.

Shneor E, Millodot M, Gordon-Shaag A, Essa M, Anton M, Barbara R, Barbara A. Prevalence of Keratoconus among Young Arab Students in Israel. Int J Kerat Ect Cor Dis 2014;3(1):9-14.

To analyze the corneal thickness development after MyoRing implantation as a tissue-related indicator of keratoconus progression.

Twelve eyes suffering from keratoconus were treated for visual rehabilitation by means of MyoRing implantation into a corneal pocket. The postoperative development of the corneal thickness at the thinnest point was analyzed. Follow-up ranged from 16 to 74 months (mean 37 months).

Out of the 12 eyes only one eye showed a thinner cornea at the last follow-up 60 months after MyoRing implan-tation compared to the last preoperative data. None of these 12 eyes required an additional intervention like corneal cross-linking, explantation or keratoplasty. Four eyes showed even thickening of the cornea during the postoperative period.

MyoRing implantation for keratoconus does not only allow visual rehabilitation. It also seems to stop the progression of the disease by creating a new biomechanical equilibrium within the tissue which eliminates a constant stimulus that drives the vicious circle of progression.

Daxer A. Corneal Thickness after MyoRing Implantation for Keratoconus. Int J Kerat Ect Cor Dis 2014;3(1):15-19.

MyoRing implantation has been shown to be able to mechanically stabilize ectatic corneas like a bone-nail for broken legs do. Here I present typical cases of MyoRing treatment for Myopia which were not eligible for LASIK.

Four eyes of four patients suffering from moderate to high myopia and showing risk factors for postoperative ectasia have been treated by MyoRing implantation. Two of them have been combined with laser vision correction (LVC).

The refractive results are comparable to those published for LVC. The cases with combined MyoRing LASIK treatment performed slightly better postoperatively than those treated with MyoRing only.

MyoRing implantation is safe and effective in myopic cases presenting with mainfest signs of keratoconus. In myopic eyes without manifest keratoconus but risk factors for post-LASIK keratectasia the combination of MyoRing implantation with Excimer Laser Surface Ablation may be a good treatment option.

Daxer A. MyoRing Treatment for Cases of Myopia not eligible for Laser Vision Correction. Int J Kerat Ect Cor Dis 2014;3(1):20-22.

Laser surgeries are effective and safe, however, over the years data has accumulated about several complications of the procedures, particularly corneal ectasia. Various studies demonstrated the importance of the front layers of the cornea to keep its structure fixed. In order to correct various degrees of myopia, different thicknesses of tissue have to be removed. Therefore, it is conceivable that the risk of developing ectasia might increase depending on the depth of corneal tissue removed.

In the last few years, the Reichert Ocular Respond Analyzer (ORA) for measuring the biomechanical parameters of the cornea has been introduced. Studies demonstrated a decrease in the corneal biomechanical parameters after Laser Assisted Sub-epithelial Keratomileusis (LASEK) surgery. However, the, relation between the depth of tissue removed and the amount of change in the biomechanical parameters had not been tested yet.

To evaluate the relationship between corneal biomechanical parameters and corneal tissue ablation thickness.

Data was retrospectively collected from patient's files that underwent LASEK in private medical center – Hadassah Optimal in Haifa between January 2009 and May 2010. All patients were operated by same surgeon (AB). In our study we included patients that had at least three ORA measurements at three set periods of time; before the operation, up to 3 months postoperative and more than 3 months postoperative. We divided the patients into 3 groups depending on the refractive error and tested the effect of variable factors (Age, Total depth ablated-TDA, percent of total depth ablated-%TDA, sex, refraction). The data was analyzed by descriptive statistics and student t-test to find the relation between LASEK and the corneal biomechanical parameters.

Ninety-eight patients participated in our study, which included 98 separate eye operations. A statistically significant decrease (p < 0.001) was found in CRF, CH, IOPg after LASEK. In group 1 (refraction −0.5 to −2.99): on CH – there was a statistically significant (p < 0.05) weak-moderate effect of TDA and %TDA (Pearson coefficient of 0.4, 0.39 respectively), statistically significant (p < 0.05) effect of age. On CRF — we found a statistically significant (p < 0.05) weak-moderate effect of TDA and %TDA (Pearson coefficient of 0.36 for both factors), statistically significant (p < 0.05) effect of age. In the second group (refraction value −3 to −5.99) only on IOPg a statistically significant (p < 0.05) weak effect of TDA (Pearson coefficient of 0.33) was demonstrated. In the third group, we did not find any effect of the variable factors on the change in biomechanical properties characteristics after LASEK.

Corneal biomechanical properties influence corneal behavior in certain eye diseases. Moreover, it has been noted that operations and procedures affect these biomechanical properties of the cornea. Hence, it is of great importance to reveal factors that could affect and change such parameters.

Barbara R, Nassar A, Zadok D, Barbara Corneal Biomechanical Properties Post-LASEK for the Correction of Myopia. Int J Kerat Ect Cor Dis 2014;3(1):23-28.

The purpose of this study is to assess the predictability, safety, efficacy and stability of correction of refractive errors in patients with keratoconus using Visian implantable collamer lens (ICL) following collagen cross-linking.

This prospective, non-comparative study evaluated 20 eyes of 14 patients with keratoconus subjected to implantation of intraocular collamer lens at least 1 year following collagen cross-linking and stable refraction. Mean preoperative myopia was −8.43 ± 5.13 Diopters (D) (–3.5 to −20.0D and mean cylinder was −2.19 ± 1.28D (0.0 to −4.5D). The preoperative spherical equivalent (SE) was −9.52 ± 5.33D (–3.75 to −21.25D). During the 12 months follow-up, uncorrected visual acuity, best corrected visual acuity, refraction, intraocular pressure and vaulting are measured.

At 12 months postoperatively, 90% of eye had refractive cylinder of <1.0D with (p = 0.003) and 20 (100%) eyes was within ±0.75D of sphere at 1 year (r² = 0.99) and (p = 0.0085). The mean postoperative BCVA in decimal was 0.498 ± 0.232, while the mean preoperative BCVA was 0.484 ± 0.285. The safety index at 12 months was 1.02. The mean postoperative UCVA in decimal was 0.498 ± 0.232 and the mean preoperative BCVA is 0.484 ± 0.29 and the efficacy index at 12 months was 1.01.

Implantation of Visian Intraocular collamer lens is predictable, safe and effective way to correct refractive error in patients with keratoconus following collagen cross-linking.

Shuber HS. Implantable Collamer Lens for Correction of Refractive Errors in Patients with Keratoconus following Collagen Cross-Linking: One Year Follow-up. Int J Kerat Ect Cor Dis 2014;3(1):29-35.

To compare corneal elevation values in normal eyes, forme fruste keratoconus (FFKC) and different stages of keratoconus using Scheimpflug imaging.

This prospective, comparative study included 267 eyes (107 normal eyes, 21 FFKC and 139 keratoconus). Keratoconic eyes were divided into four groups according to keratometry values. Maximum posterior elevation (PE) above the (best fit sphere (BFS) at the central 5 mm were measured using the Pentacam (Oculus Optikgeräte GmbH). Receiver operating characteristic curves were used to determine the test's overall predictive accuracy and to identify optimal cutoff points to discriminate between the groups.

PE had the smallest values in normal eyes and increased in FFKC and each progressive stage of keratoconus. Mean PE was 9.98 ± 5.33 µm in normal eyes, 18.09 ± 9.23 µm in FFKC and 24.97 µm ± 15.89, 37.82 ± 18.64, 46.82 ± 21.41 and 66.07 ± 39.09, in keratoconus stage I, II, III and IV respectively.

Posterior elevation values increased according to the severity of keratoconus disease. PE can be used as indicator of keratoconus progression.

Henriquez MA, Izquierdo L Jr, Dañin D. Corneal Elevation Values in Normal Eyes, forme fruste Keratoconus and Keratoconus at Different Stages Measured by Scheimpflug Imaging. Int J Kerat Ect Cor Dis 2014;3(1):36-39.

Pereira LC, Siqueira R, Valbon B, Santos R, Dawson D, Ambrósio R, Siqueira JA. Long-term Improvement after the Athens Protocol for Advanced Keratoconus with Significant Ectasia Progression in the Fellow Eye. Int J Kerat Ect Cor Dis 2014;3(1):40-43.

Zauberman NA, Rootman DS. Post- LASIK Keratoectasia Developing with Sleep Apnea and Floppy Eyelid Syndrome: Case Report and Review of the Literature. Int J Kerat Ect Cor Dis 2014;3(1):44-46.

To report a case of post-LASIK unilateral corneal ectasia.

Department of anterior segment and Refractive surgery, Rothschild Foundation, Paris.

A 33-year-old woman was referred with a history of unilateral post-LASIK ectasia in her left eye, 18 months post operatively. Her best-corrected visual acuity was 20/20 with a manifest refraction of +1.75 (–4.75 × 90). Orbscan ii® revealed an inferior steepening associated with irregular astigmatism. The preoperative Placido topographies revealed a slight skewed radial axis in the right eye associated with an inferior-superior keratometry difference of 1.6 Diopters at 3 mm. in the left eye that developed ectasia, regular symmetric astigmatism was present. Uncorrected visual acuity improved to 20/25 2 weeks after keraRing® segment insertion.

Berguiga M, saad a, Gatinel D. Unilateral Post-LASIK Ectasia in a Topographical Normal Eye with a slight asymmetry in the Contralateral Eye. int J kerat Ect Cor Dis 2014;3(1):47-51.