To establish consensus on definitions and concepts of keratoconus and ectatic corneal diseases by using Delphi approach.

Seventeen Latin American experts on keratoconus and ectatic corneal diseases participated in a 3-round Delphi panel approach. A web-based 12 question survey was answered by panelists in two rounds, followed by life discussion meeting. A two-third majority strategy was defined as a consensus.

Corneal ectatic diseases were defined as progressive thinning conditions without acute stromal inflammation, and were classified as keratoconus, pellucid marginal degeneration (PMD), keratoglobus, and ectasia after trauma or surgery. The pattern of thinning was considered the main aspect for the classification of ectatic diseases, but criteria for staging the disease needs to be improved. Corneal tomography with 3D reconstruction, distinguished from Placido-disk based front surface topography was elected as the diagnostic procedure currently capable of detecting the earliest clinical ectatic changes. Biomechanical alterations were considered to be the first event for ectasia development. Eye rubbing was directly related to the development and progression of ectasia. Inflammation was considered as a possible event on the physiopathology. Keratoconus was considered as a bilateral disease, with often asymmetric presentation, while ectasia may occur unilaterally if there is significant corneal insult, leading to biomechanical failure. No consensus was achieved for the definitions on forme fruste keratoconus (FFKC).

Consensus was achieved on definitions of corneal ectatic diseases. Disease staging, including criteria for FFKC or subclinical ectasia remains controversial. A larger consensus including experts from different groups around the world is needed.

Ambrósio RJr, Belin MW, Perez VL, Abad JC, Gomes JAP. Definitions and Concepts on Keratoconus and Ectatic Corneal Diseases: Panamerican Delphi Consensus — A Pilot for the Global Consensus on Ectasias. Int J Kerat Ect Cor Dis 2014;3(3):99-106.

To evaluate the effect of riboflavin and ultraviolet- A-induced corneal collagen crosslinking (CXL) on high order aberrations (HOA) up to third-order at 6 months using the iTrace wavefront aberrometer in patients with progressive keratoconus and post-LASIK ectasia.

Ongoing retrospective chart review of patients having undergone CXL. The iTrace (Tracey Technologies, Houston, TX) was used to evaluate HOA. Patient data was collected from a single clinical site pre- and 6 months postoperatively. Data collected included logMAR uncorrected distance visual acuity (UDVA), logMAR corrected distance visual acuity (CDVA), manifest refraction, and HOA measurements. Data was analyzed with paired two-tailed student's t-test.

18 eyes (9M:4F, mean age 29.2 years, range 16-45) had 6 months of follow-up. Total HOAs, total coma and total trefoil were significantly reduced at 6 months by 16, 33 and 26% respectively (p < 0.05). Nonsignificant trends toward improvement were seen in spherical aberration, secondary astigmatism and UDVA. There were no statistically significant changes in manifest refraction or CDVA.

Improvement in high order aberration profile is one mechanism by which corneal collagen crosslinking enhances visual function in ectatic corneas. Total HOA and total coma measures are the most commonly reported improvements in HOA measures in previous studies, while total trefoil has only been observed in one other study. The improvements seen in HOAs remain fairly modest which likely accounts for the lack of measureable improvement in high-contrast visual acuity measures, such as Snellen UDVA and CDVA. This study is the first to report HOA outcomes with the iTrace wavefront aberrometer.

Muzychuk A, Penner V, Rocha G. High Order Aberration Outcomes of Corneal Collagen Crosslinking in Eyes with Keratoconus and Post-LASIK Ectasia. Int J Kerat Ect Cor Dis 2014;3(3):107-112.

To utilize Scheimpflug imaging to describe corneal changes in keratoconic patients undergoing collagen cross- linking.

Case series.

Retrospective chart review at two sites: Calgary, Alberta and Brandon, Manitoba, Canada. All patients were diagnosed with keratoconus and had undergone corneal collagen crosslinking. All patients had pre- and post-procedure imaging done with Oculus Pentacam.

Sixty-one eyes of 48 patients with 6 months follow- up and 36 eyes of 27 patients with one year follow-up were included. Average age was 27 ± 12 years (15-48 years). Fifty- one males and 10 females were studied. At 1 year follow-up, all Pentacam indices were found to improve: ISV −4.44 ± 18.6 (p = 0.16), IVA −0.07 ± 0.27 (p = 0.12), KI −0.009 ± 0.082 (p = 0.49), CKI −0.012 ± 0.027 (p = 0.01), IHA −3.87 ± 23.3 (p = 0.33) and IDH −0.062 ± 0.308 (p = 0.24). Keratometry measurements were flatter at the pupil centre by 0.87 ± 2.53 D (p = 0.05). Kmax and Kmin were flatter by 0.58 ± 1.37 D (p = 0.02) and 0.33 ± 1.70 D (p = 0.25) respectively. Pupil center pachymetry was thinner by 12.9 ± 21.1 µm (p = 0.0006) at 6 months, as were the corneal apex and thinnest local by 12.9 ± 22.3 µm (p = 0.001) and 21.8 ± 54.6 µm (p = 0.05) respectively. However, all central pachymetry readings were not statistically different from baseline at the one year measurements. Peripheral corneal measurements at 6 mm diameter were no different from baseline at 6 months, however, were significantly thicker at the 1 year follow-up.

The data, in this study, points to a more uniform cornea post corneal collagen crosslinking. The inferior cornea becomes flatter and superior cornea steeper with less variation when comparing the corneal curvatures. The peripheral cornea becomes thicker at 1 year post-procedure. Collagen cross- linking stabilizes the cornea.

Penner V, Muzychuk A, Al-Ghoul A, Rocha G. The Effects of Epithelium-off Corneal Collagen Crosslinking on Peripheral Corneal Keratometry, Pachymetry as well as Scheimpflug Imaging Calculated Corneal Indices in Keratoconus. Int J Kerat Ect Cor Dis 2014;3(3):113-117.

Hawkes E, Nanavaty MA. Eye Rubbing and Keratoconus: A Literature Review. Int J Kerat Ect Cor Dis 2014;3(3):118-121.

The purpose of this study is to evaluate the topographic, topometric and visual changes after implantation of Ferrara intrastromal corneal ring segments (ICRS) in grades I and II keratoconus patients.

The chart records of 50 consecutively operated keratoconus patients were reviewed. The patients were operated on by the same surgeon, with the manual technique. All patients were preoperatively and postoperatively evaluated with the Pentacam (OCULUS Optikgeräte, Wetzlar, Germany). The studied parameters were: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), keratometry, corneal asphericity and corneal volume.

Fifty eyes of 42 patients (26 males and 16 females) were analyzed. The mean preoperative UDVA was 0.91 ranging from LogMAR 0.10 to 1.30. The mean postoperative CDVA was 0.19 ranging from 0.00 to 0.54 LogMAR. The postoperative CDVA was equal or better than 0.18 in 37 cases (74%). The mean K1 decreased from 45.80D (±2.52) preoperatively to 44.27D (± 2.10) postoperatively and the mean K2 value, from 49.06D (± 2.09) to 46.22D (±1.89). The mean asphericity increased from −0.71 preoperatively to −0.29 postoperatively. The average preoperative corneal volume was 56.89 ± 3.11 mm3 while the average postoperative corneal volume was 57.64 ± 3.05 mm³.

The study supports the early indication of implantation of Ferrara ICRS in mild to moderate keratoconus cases in order to achieve good visual, keratometric and ashpericity outcomes.

Rodrigues PF, Ferrara G, Ferrara P, Dias WG, Torquetti L. Intrastromal Corneal Ring Segments Implantation in Patients with Mild Keratoconus. Int J Kerat Ect Cor Dis 2014;3(3):122-126.

To report successful visual rehabilitation of post refractive surgery keratoectasia shortly after corneal collage crosslinking (CXL) procedure achieved with silicone hydrogel mini-scleral (SHmS) contact lens.

A 29-year-old woman attended to our clinic with complaints on decreased vision in her left eye. Twelve years earlier she underwent bilateral laser-assisted in situ keratomileusis (LASIK) procedure for myopia correction. Corneal topography revealed bilateral central keratoectasia with maximal keratometry values of 55.4 Diopter (D) for her right eye and 59.7 D for the left, corneal thicknesses were 422 and 443 respectively. The patient underwent an uneventful CXL procedure in her left eye and was fitted with SHmS lens 5 weeks later. The lens was designed to rest over the patients’ sclera and perilimbal cornea and vault the central cornea with minimal support over it.

SHmS lens fitting resulted in significant subjective improvement in visual acuity (from 20/200, unaided to 20/25, contact lens corrected). The patient was able to wear the lens upto 10 hours a day with stable contact lens corrected vision. No contact lens related complications, such as edema or neovascularization were observed during 3 months follow-up period. As a result of successful restoration of vision in the CXL-treated eye, the patient was scheduled for the procedure in her other eye.

SHmS contact lens should be considered as an option for the visual rehabilitation of corneas shortly after collagen corneal crosslinking procedure. This novel contact lens modality made from flexible and highly gas permeable material minimizes contact lens influence on corneal recovery after CXL and provides an excellent visual outcome.

Severinsky B. Silicone Hydrogel Mini-scleral Contact Lenses after Corneal Collagen Crosslinking for Post-LASIK Keratoectasia. Int J Kerat Ect Cor Dis 2014;3(3):127-129.

To report the clinical features of five siblings, four of them with positive diagnostic of keratoconus in different degrees of severity as well as their parents findings.

Seven elements of the same family, five young siblings (2 males, 3 females), and their parents were screened for potential keratoconic signs. Topographic data from 60 normal eyes are also reported for comparison purposes. Complete ophthalmologic examination including biomicroscopic, topographic and refractive examination. Main outcome measures included biomicroscopic findings, refractive error and visual acuity, simulated keratometry, corneal eccentricity, indices of asymmetry and regularity.

The more advanced case was present in the left eye of a male member, needing a rigid gas permeable lens to correct irregular astigmatism. Another brother also presented bilateral mild to moderate keratoconus with no apparent vision complaints. The third case diagnosed was one sister with history of monthly disposable soft toric lens to compensate a presumed initially regular astigmatism two years before. The remaining two cases being the older sister and one of the younger sisters presented the less noticeable signs, with confirmation of the pathology only in one of them and warranting a close follow- up of both due to the asymmetric corneal topography between both eyes as well as between the flatter superior and steeper inferior corneal areas.

This is the first reported case series involving diagnosis of keratoconus or atypical corneal topographies in several young siblings and their parents. Further evaluation of this and other cases with similar presentations might help to gain a deeper understanding on the potential genetic paths of keratoconus.

González-Méijome JM, Peixoto-de- Matos SC, Soares A, Queirós A, Díaz-Rey A, Salgado-Borges J. Topographical Irregularity and Keratoconic Findings in Five Siblings and their Parents. Int J Kerat Ect Cor Dis 2014;3(3):130-135.

Rocha G, Torquetti L, Rocha A. Transient Keratoconus following Acute Conjunctivitis. Int J Kerat Ect Cor Dis 2014;3(3):136-140.