Corneal ectasia associated with posterior lamellar opacification.

BACKGROUND: Concomitant corneal ectasia and posterior lamellar corneal opacification is rare, and the genetic relationship between these two conditions is unclear. We report the genetic and clinical characterization of this phenotype in three unrelated individuals. MATERIALS AND METHODS: One previously reported affected individual and two unreported, unrelated, affected individuals were recruited for the study. Subjects and unaffected relatives underwent slit lamp examination, refraction, and multi-modal imaging. Saliva samples were obtained from two of the three affected individuals, from which DNA was extracted. Sanger sequencing was performed to identify mutations in genes associated with posterior amorphous corneal dystrophy (PACD), brittle cornea syndrome (BCS), and posterior polymorphous corneal dystrophy (PPCD), while copy number variation (CNV) analysis was used to identify CNV in the PACD locus. RESULTS: Affected individuals demonstrated bilateral corneal steepening, stromal thinning and lamellar posterior corneal opacification. Corneal topography and tomography revealed conical or globular corneal steepening and decreased thickness. Anterior segment optical coherence tomography demonstrated hyperreflectivity of the posterior stroma in each of the affected individuals. Genetic testing did not detect a heterozygous deletion involving the PACD locus on chromosome 12 or a pathogenic mutation in the genes associated with BCS or PPCD. CONCLUSIONS: Corneal ectasia may be associated with posterior lamellar stromal opacification that appears consistent with PACD. However, genetic testing for PACD as well as BCS and PPCD in affected individuals fails to reveal pathogenic deletions or mutations, indicating that other genetic factors are involved.

Collagen I Defect Corneal Profiles in Osteogenesis Imperfecta.

PURPOSE: The goal of this study was to evaluate corneal profiles of patients with osteogenesis imperfecta (OI) due to a collagen I gene mutation. METHODS: This was a cross-sectional comparative study. There were 84 eyes from 42 patients with OI types I, III, and IV who were recruited from the OI Clinic at the Clinical Hospital of Porto Alegre, Brazil. All cases presented either COL1A1 or A2 gene mutations. Controls were matched by sex, age, and refractive error. Corneal Scheimpflug tomography was used to determine curvature and thickness parameters in both groups. RESULTS: Quantitative collagen mutations were found only in OI type I. Qualitative mutations were responsible for all mutations observed in type III and IV patients. Each OI type presented significantly lower pachymetric values at the thinnest point compared with controls (443.7-505.1 vs. 541.9-548.5 µm; P < 0.001). In addition, significantly lower pachymetric values were observed in patients with OI compared with controls in all positions between the central and corneal periphery (581.4-657.0 vs. 704.5-720.7 µm at an 8.0-mm-diameter circle; P < 0.001). Differences in anterior and posterior radii of curvatures, respectively, between patients with OI and controls were not statistically significant (7.64-7.80 vs. 7.65-7.69 mm; P > 0.05) except for a lower anterior radii of curvatures in type III (7.33 vs. 7.72 mm; P < 0.01). CONCLUSIONS: Although patients with OI have homogenously thinner corneas compared with controls, we observed that a collagen I chain mutation was not responsible for corneal curvature alterations in OI.

Gender differences in keratoconus keratoplasty: a 25-year study in Southern Brazil and global perspective.

PURPOSE: To compare the characteristics and outcomes of male and female patients that underwent corneal transplantation for keratoconus (KC) in Southern Brazil and worldwide. METHODS: Retrospective longitudinal study that evaluated medical records of patients who were submitted to keratoplasty between August 1990 and September 2015 in two tertiary hospitals in the state of Rio Grande do Sul (Brazil) and review of the Medline and Embase database international literature. RESULTS: Out of a total of 4026 corneal transplants at that period, 1284 patients (1530 eyes) received preoperative diagnosis of KC (31.8%). A total of 839 men underwent keratoplasty for KC (65.4%) with mean age of 30.3 (±12.2) years. The 445 transplanted women (34.6%) had a mean age of 34.5 (±14.8) years. Both differences were statistically significant (p < 0.01). Regarding laterality, skin color, recipient and donor cornea trephination diameter, and rejection episodes there was no significant difference between the two groups at baseline (p > 0.05). Females were submitted significantly more to deep anterior lamellar keratoplasty (DALK) in comparison with males (26.5 vs. 15.7%, p < 0.01). We were able to include 57.4% of the original keratoplasties for our follow-up data analysis. Male sex and penetrating keratoplasty (PK) were associated significantly with increased risk for graft failure in KC transplantation at the end of follow-up (p < 0.05). The mean follow-up of transplanted patients was similar in both groups. CONCLUSION: Keratoconus is the most transplanted corneal disease in Southern Brazil and globally. Studies in Africa, Asia, Europe and North America also showed gender differences in KC patients submitted to keratoplasty. We found that men were transplanted in a 1.9 male/female ratio and at an earlier age than women. At final follow-up, male sex and PK were risk factors associated with increased graft failure. It is essential to broaden the hormonal and genetic investigations to elucidate why keratoconic males have undergone more keratoplasties and have more secondary failure than females.

Scleral Pneumatonometry in Penetrating Keratoplasty: A Clinical Study.

PURPOSE: To evaluate the reliability between pneumatonometry intraocular pressure (IOP) measurement in different scleral locations and corneal IOP in a penetrating keratoplasty (PK) setting. Our aim is to validate a method that can potentially be used for patients with keratoprostheses. METHODS: This is a prospective observational study of 40 patients who underwent monocular PK by a single surgeon and had no significant anterior segment condition in the contralateral eye. Participants were recruited during routine visits to the Cornea Clinic at the Stein Eye Institute, between November 2016 and February 2017. Goldmann applanation tonometry, central corneal pachymetry, and inferior, inferotemporal, and temporal scleral pneumatonometry of both eyes were collected. RESULTS: The correlation coefficient between corneal Goldmann applanation tonometry IOP and inferior, inferotemporal, and temporal scleral pneumatonometry IOP in the transplanted eye found that all locations were significantly and strongly correlated (r = 0.76, r = 0.80, and r = 0.75, respectively; P < 0.001). The correlation coefficient was higher for inferior and inferotemporal scleral measurements when the contralateral eye was used to predict the PK corneal IOP (r = 0.85 and r = 0.79, respectively; P < 0.001) and weaker for temporal measurement (r = 0.72; P < 0.001). Central corneal thickness correction formulas did not improve the correlation between scleral and corneal IOPs. All linear regression analyses were statistically significant (P < 0.001). CONCLUSIONS: The inferotemporal sclera was the optimal location for pneumatonometry IOP measurement. The contralateral eye could be used to more accurately predict the IOP in the eye of interest. Scleral pneumatonometry is an intuitive and reliable method to monitor IOP when corneal measurement is not available.

Update and review of Urrets-Zavalia syndrome.

For more than half a century, Urrets-Zavalia syndrome (fixed dilated pupil) has been described as a postoperative complication of ophthalmic surgery. Since first reported as a complication of penetrating keratoplasty for keratoconus in patients receiving atropine, the characteristic features of Urrets-Zavalia syndrome have been expanded. In previous literature, a total of 110 cases resulted in a fixed and dilated pupil. Increased intraocular pressure (IOP) in the immediate postoperative period, phakia, and air or gas in the anterior chamber appear to be the most important risk factors for Urrets-Zavalia syndrome following ophthalmic procedures. Mannitol, IOP control, the removal of air or gas in the anterior chamber, and iridectomy have all demonstrated utility in managing Urrets-Zavalia syndrome.

Update and review of Urrets-Zavalia syndrome / Atualizando e revisando a síndrome de Urrets-Zavalia

ABSTRACT For more than half a century, Urrets-Zavalia syndrome (fixed dilated pupil) has been described as a postoperative complication of ophthalmic surgery. Since first reported as a complication of penetrating keratoplasty for keratoconus in patients receiving atropine, the characteristic features of Urrets-Zavalia syndrome have been expanded. In previous literature, a total of 110 cases resulted in a fixed and dilated pupil. Increased intraocular pressure (IOP) in the immediate postoperative period, phakia, and air or gas in the anterior chamber appear to be the most important risk factors for Urrets-Zavalia syndrome following ophthalmic procedures. Mannitol, IOP control, the removal of air or gas in the anterior chamber, and iridectomy have all demonstrated utility in managing Urrets-Zavalia syndrome.

RESUMO Por mais de meio século, a síndrome de Urrets-Zavalia (pupila fixa e dilatada) foi descrita como uma complicação pós-operatória em oftalmologia. Desde o primeiro relato após ceratoplastia penetrante em pacientes portadores de ceratocone em uso de atropina, seu conceito foi ampliado. Na literatura, um total de 110 casos resultaram em pupila fixa e dilatada. Aumento da pressão intraocular (PIO) no pós-operatório imediato, facia, ar ou gás na câmara anterior parecem ser fatores de risco importantes para o aparecimento da síndrome. Sua prevenção pode ser alcançada com o uso de manitol, controle adequado da PIO e quantidade de ar ou gás na camâra anterior e iridectomia.

Topical 0.03% tacrolimus preventing rejection in high-risk corneal transplantation: a cohort study.

BACKGROUND/AIMS: The present study aims to identify the rate of rejection and safety of 0.03% tacrolimus eye drops associated with 1% prednisolone in a topical formulation, comparing them with the use of 1% prednisolone eye drops alone in patients with high-risk corneal transplantation. METHODS: Retrospective cohort study with 72 patients (72 eyes) who underwent more than one penetrating keratoplasty (PK) in the same eye or had severe chemical burn between 2004 and 2011 in the department of cornea and external disease of the Clinical Hospital of Porto Alegre, Brazil. We compared the records of 36 patients that performed unilateral PK and received only 1% prednisolone eye drops between May 2004 and July 2008, with 36 patients that received 0.03% tacrolimus eye drops in addition to 1% prednisolone between August 2008 and August 2011. RESULTS: The mean follow-up of the group exposed to tacrolimus was 23.1 months and 24.0 in the prednisolone alone group. The demographics, intraoperative and initial indications for first PK were similar between groups, as well as the number of regrafts performed. Intraocular pressure (IOP) was not statistically different among groups. Regarding irreversible rejections, topical tacrolimus showed greater protection: only seven grafts (19.4%) lost transparency against 16 (44.4%) in the 1% prednisolone alone group (p <0.05). CONCLUSIONS: Topical 0.03% tacrolimus was effective in preventing irreversible rejection in patients with high-risk corneal transplantation without increasing IOP.