ASSOCIATION STUDY BETWEEN POLYMORPHISMS OF THE p53 AND LYMPHOTOXIN ALPHA (LTA) GENES AND THE RISK OF PROLIFERATIVE VITREORETINOPATHY/RETINAL DETACHMENT IN A MEXICAN POPULATION.

PURPOSE: To report the results of an association study between single-nucleotide polymorphisms of the p53 and LTA genes and the risk of proliferative vitreoretinopathy (PVR)/retinal detachment (RD) in a Mexican cohort. METHODS: A total of 380 unrelated subjects were studied, including 98 patients with primary rhegmatogenous RD without PVR, 82 patients with PVR after RD surgery, and 200 healthy, ethnically matched subjects. Genotyping of single-nucleotide polymorphisms rs1042522 (p53 gene) and rs2229094 (LTA gene) was performed by direct nucleotide sequencing. Allele frequencies, genotype frequencies, and Hardy-Weinberg equilibrium were assessed with HaploView software. RESULTS: No significant differences in the allelic distributions of the previously identified risk C allele for LTA rs2229094 were observed between RD subjects and controls (odds ratio [95% confidence interval] = 0.8 [0.5-1.2]; P = 0.3). Conversely, the C allele for rs1042522 in p53 was positively associated with an increased risk for RD (odds ratio [95% confidence interval] = 1.4 [1.01-1.9]; P = 0.04). No significant differences were observed when the subgroup of 82 RD + PVR subjects was compared with the subgroup of 98 patients with RD. CONCLUSION: The C allele for rs1042522 in p53 was genetically associated with a higher risk for RD but not for PVR in this cohort. This is the first association study attempting replication of PVR-associated risk alleles in a nonwhite population.

In-vitro evaluation of the evaporation retardation by Meibomian lipids in homogeneous and non-homogeneous evaporation.

HYPOTHESIS: An important function of the Tear Film Lipid Layer (TFLL) is the retardation of evaporation. We propose two micro-scaled systems to quantify the influence of the TFLL in evaporation for single patients, which may contribute as an improvement on the diagnosis of Meibomian Gland Dysfunctions (MGD). EXPERIMENTS: Meibum was extracted from 10 patients with hypersecretory MGD and 9 healthy controls. The lipids were placed over water, and the evaporation was determined in the case of homogeneous evaporation over a surface (pendant drop), and the case where the evaporation depends on a pinned triple contact line (meniscus). FINDINGS: For the homogeneous case, the presence of Meibum reduced evaporation in 30%, although there was no significant difference between controls and MGD patients. However, evaporation induced by menisci was 25 % higher in MGD patients. Our results contribute to the evidence of the inhibition of evaporation by Meibum. Our study also suggests that the evaporation induced by contact points may be a more relevant model to measure differences in evaporation due to the composition of Meibum. This model may also have connotations in the occurrence of internal stresses in the tear film, inducing its instability.

Combined Bacterial and Herpes Simplex Virus Keratitis following Small-Incision Lenticule Extraction for the Correction of Myopia.

A 28-year-old male presented unilateral visual loss, intense ocular pain, redness and intraocular hypertension in his right eye 2 days after undergoing small-incision lenticule extraction (SMILE) in both eyes. Initial examination of the affected eye revealed the presence of white infiltrates within the corneal interface, as well as a central epithelial defect. The patient was diagnosed with infectious keratitis, posteriorly the eye was irrigated with balanced saline solution and treatment was initiated with hourly moxifloxacin 0.5%. Since this approach failed to resolve symptoms, a sample from the interface was obtained for PCR assay, which revealed the presence of herpes simplex virus DNA, confirming the cause of the infection. The patient was prescribed a regimen of oral acyclovir, topical ganciclovir and prednisolone. Clinical improvement following resolution of the epithelial defect was observed. Although rare, herpetic keratitis following SMILE is best managed via early diagnosis and initiation of appropriate anti-herpetic treatment.

Pain Management in Corneal Collagen Crosslinking for Keratoconus: A Comparative Case Series.

Purpose: To compare management of postoperative pain after corneal collagen crosslinking (CXL) with oral gabapentin or ketorolac. Methods: Prospective interventional comparative case series in a single center. Patients undergoing epithelium-off (epi-off) or epithelium-on (epi-on) techniques performed by a single surgeon for progressive keratoconus were enrolled and randomly assigned to the ketorolac (10-mg tablets every 8 h) or the gabapentin (300-mg capsules every 8 h) group and instructed to take the medication for the first 3 postoperative days. Using a numeric scale of pain, scores were assessed for current pain (at the time of applying the questionnaire), and average pain over the preceding 24 h. Eye symptoms and systemic adverse events related to oral medication were also assessed. Results: Thirty-seven patients were included, with 22 (10 epi-on and 12 epi-off) assigned to the ketorolac group and 15 (7 epi-on and 8 epi-off) to the gabapentin group. No statistically significant differences were noted on the pain scale between groups at any point of the study, in the median pain scores of patients at the time of applying the questionnaire, nor in the severity of pain during the 24-h period before the assessment. Also, no differences were found among groups for the eye symptoms and the systemic adverse events. The median regression analysis showed no effect of the type of surgery or gender in the severity of pain. Conclusions: Both oral ketorolac and oral gabapentin can be used with similar results for pain and symptomatic control after epi-on or epi-off CXL procedures.

Sclerocornea-Microphthalmia-Aphakia Complex: Description of Two Additional Cases Associated With Novel FOXE3 Mutations and Review of the Literature.

PURPOSE: To describe 2 sporadic Mexican patients having congenital bilateral, total sclerocornea, aphakia, and microphthalmia associated with novel mutations in the FOXE3 gene. METHODS: Two affected individuals with congenital bilateral, total sclerocornea, aphakia, and microphthalmia underwent detailed examinations including slit-lamp examination, visual acuity, and intraocular pressure measurements. Ocular ultrasonography and ultrasound biomicroscopy were performed. Genomic DNA was isolated from blood leukocytes in each subject, and molecular analysis of the FOXE3 gene was performed. For cosegregation analysis, presumable pathogenic variants were tested by Sanger sequencing in parental DNA. RESULTS: Molecular screening of FOXE3 was performed in 2 cases with congenital bilateral, total sclerocornea, aphakia, and microphthalmia. In patient 1, genetic analysis demonstrated a novel homozygous c.291C>G (p.Ile97Met) FOXE3 pathogenic variant. In patient 2, compound heterozygosity for the novel c.387C>G (p.Phe129Leu) transversion and for the previously reported c.244A>G (p.Met82Val) transition, was recognized. CONCLUSIONS: The sclerocornea-microphthalmia-aphakia complex is a severe malformative ocular phenotype resulting from mutations in the FOXE3 transcription factor. To date, patients from at least 14 families with this uncommon ocular disorder have been described. The identification of 2 novel pathogenic variants in our patients expands the mutational spectrum in FOXE3-related congenital eye disorders. In addition, we performed a review of the clinical and genotypic characteristics of all published patients carrying biallelic FOXE3 mutations.