To evaluate the expression patterns of cytokeratin (K) 12, 13, and 19 in normal epithelium of the human ocular surface to determine whether K13 could be used as a marker for conjunctival epithelium. Total RNA was isolated from the human conjunctiva and central cornea. Those transcripts that had threefolds or higher expression levels in the conjunctiva than the cornea were identified using microarray technique. Expression levels of three known signature genes and of two conjunctival genes, K13 and K19 were confirmed by using quantitative real-time PCR (qRT–PCR). Protein expression of K12, K13, and K19 was confirmed by immunostaining with specific antibodies on histologic sections of human sclerocornea that contained the conjunctiva, limbus, and cornea and on impression cytology (IC) specimens of the cornea and conjunctiva from normal donors. Double staining of K13/K12 and K19/K12 on histologic sections and IC specimens was performed. There were 337 transcripts that were preferentially expressed in the conjunctiva. K13 and K19 were among the top twenty transcripts in the conjunctiva and this preferential expression pattern of K13 and K19 was confirmed by qRT–PCR. Immunohistochemical studies showed that K13 was expressed at the posterior limbal epithelium and conjunctival epithelium but was totally absent in the cornea. K12 was expressed in the corneal and anterior limbal epithelia except for the basal layer and was absent from the conjunctiva. In contrast, K19 was detected in the corneal, limbal and conjunctival epithelia. Immunostaining of the IC specimens showed K12+ epithelial cells in the corneal region, K13+ cells in the conjunctival area, and K19+ cells in the corneal and conjunctival specimens. Expression of K13 and K12 on the ocular surface was mutually exclusive on both the histologic and IC samples using double immunostaining. K13 is more specific to the conjunctival epithelial cells than K19 and potentially could be used as a marker to identify conjunctival epithelial cells in limbal stem cell deficiency.

To report the long-term refractive outcomes, safety, predictability, efficacy and complications of 349 eyes treated with posterior chamber phakic intraocular lenses (pIOLs). A retrospective review of consecutive clinical cases of patients who underwent spheric implantable collamer lens (ICL) and toric ICL (TICL) implantation. The study included 349 eyes of 216 patients with sphere between +8 to −24 diopters (D) and 0 to −6.5 D of astigmatism. Statistical analysis was performed to identify differences between preoperative and postoperative refractive outcomes. Main outcome measures were preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical and cylindrical errors and spherical equivalent and significant postoperative complications. 194 eyes were treated with TICL and 155 eyes with ICL. The mean age of the patients was 29 ± 6.7 years. The mean preoperative sphere was −10.35 ± 5.1 D (+8 to −24) and the postoperative sphere was −0.09 ± 1.06 D (+3.25 to −6.5), p < 0.001. Preoperative cylinder was −2.63 ± 1.44 (0 to −6.5 D) and postoperative cylinder was −0.97 ± 0.89 D (0 to −3.5), p < 0.001. The preoperative mean spherical equivalent was −11.6 ± 5.12 D (+7.875 to −25.625) and postoperative spherical equivalent was −0.52 ± 1.03 (+2.25 to −6.75), p < 0.001. The mean preoperative UDVA was 1.72 ± 0.49 and postoperative UDVA was 0.23 ± 0.22, p < 0.001. The mean preoperative CDVA was 0.21 ± 0.17 and postoperative CDVA was 0.12 ± 0.138, p < 0.001. The implantation of posterior chamber pIOLs is a safe, predictable and effective strategy to manage refractive errors during long-term follow-up.

Background: Infectious keratitis is a sight-threatening condition for children. The purpose of this study was to describe the clinical profile, risk factors and microbiological profile of infectious keratitis in children.Methods: Retrospective review of clinical records of patients under 16 years of age with history of microbial keratitis seen at a tertiary referral center. Clinical characteristics, risk factors, visual and surgical outcomes as well as the microbiological profile are analyzed.Results: Forty-one eyes of 41 patients. Mean age was 8.7 years. Time between the onset of symptoms and ophthalmological examination was 12.7 days. Predisposing factors were found in 78%; ocular trauma was the most common (25%). Visual acuity equal or worse than 20/200 at admission correlated positively with a poorer visual outcome, p=0.002. Positivity of cultures was 34%. Gram-positive bacteria were isolated in 78.5%;Staphylococcus epidermidis(28.6%) was the most common microorganism.Conclusions: Our study emphasizes the importance of a prompt diagnosis and treatment of infectious corneal ulcers in children. Trauma and contact lenses were the main predisposing factors. Gram-positive organisms were isolated in the vast majority of cases and visual outcomes are usually poor.

Dry eye disease (DED) has a higher prevalence than many important systemic disorders like cardiovascular disease and diabetes mellitus, representing a significant quality of life burden for the affected patients. It is a common reason for consultation in general eye clinics worldwide. Nowadays, the diagnostic and therapeutic approach at the high corneal and ocular surface specialty level should be reserved for cases of severe and chronic dry eye disease associated with systemic autoimmune diseases or complicated corneal and ocular surface pathologies. In such cases, the diagnostic and therapeutic approach is often complex, elaborate, time-consuming, and costly due to the use of extensive dry eye questionnaires, noninvasive electronic diagnostic equipment, and clinical laboratory and ancillary tests. However, other eye care specialists attend a fair amount of DED cases; therefore, its diagnosis, classification, and management should be simple, practical, achievable, and effective. Considering that many patients attending non-specialized dry eye clinics would benefit from better ophthalmological attention, we decided to elaborate a practical DED classification system based on disease severity to help clinicians discriminate cases needing referral to subspecialty clinics from those they could attend. Additionally, we propose a systematic management approach and general management considerations to improve patients’ therapeutic outcomes according to disease severity.

PURPOSE: To compare the maximum posterior elevation (MPE) measurements before and after LASIK using a dual rotating Scheimpflug (DRS) imaging system (Galilei, Ziemer Ophthalmic Systems, Port, Switzerland) and a scanning slit-beam (SSB) imaging system (Orbscan IIz, Bausch & Lomb, Rochester, NY). METHODS: This retrospective study included 78 eyes from 78 patients who underwent myopic LASIK. Preoperative and postoperative data collected included anterior and posterior best-fit sphere radius and axial curvature readings, posterior central elevation (PCE), and MPE relative to a best-fit sphere using a 7.8-mm region of interest. Data were compared using paired t test analysis. RESULTS: Mean preoperative PCE (5.06 ± 2.29 μm with the DRS system and 12.78 ± 6.90 μm with the SSB system) and MPE (4.87 ± 4 μm with the DRS system and 15.44 ± 9.78 μm with the SSB system) were statistically different ( P < .001). Mean postoperative PCE (4.55 ± 2.34 μm with the DRS system and 20.59 ± 8.11 μm with the SSB system) and MPE (4.90 ± 3.35 μm with the DRS system and 24.95 ± 10.15 μm with the SSB system) were statistically different ( P < .001). The difference between preoperative and postoperative MPE measurements by DRS was not statistically significant ( P = .953), whereas the difference measured by SSB was statistically significant ( P < .001). CONCLUSIONS: The consistency of DRS measurements suggests that the posterior surface of the cornea does not change appreciably after keratorefractive surgery and is imaged more accurately using DRS compared with SSB. The DRS system affords confidence in interpreting data that are useful for discerning morphologic abnormalities of the cornea, both before and after keratorefractive surgery.