John J. Males

Polymicrobial keratitis after a collagen cross-linking procedure with postoperative use of a contact lens: a case report.

Purpose: To report a case of polymicrobial keratitis caused by Streptococcus salivarius, Streptococcus oralis, and coagulase-negative Staphylococcus sp. in a patient who underwent collagen cross-linking for keratoconus. Method: Case report. Result: A 32-year-old male presented with a 1-day history of a painful red eye, occurring 3 days after he had undergone a collagen cross-linking with riboflavin and UV-A on his left eye for keratoconus. He admitted to removing his bandage contact lens and cleaning it in his mouth before reapplying it in his eye. On presentation, a severe keratitis with an 8-mm epithelial defect and 360-degree ring infiltrate was found. Culture results from his contact lens were positive for S. salivarius and S. oralis, and coagulase-negative Staphylococcus sp. were grown from his corneal scrapings. Conclusions: Collagen cross-linking is a promising procedure for the treatment of progressive keratoconus with minimal reported side effects. However, the possibility of a secondary infection after the procedure exists because the patient is subjected to epithelial debridement and the application of a soft contact lens. The role of the UV light on the immune mechanisms of the cornea and its effect on corneal wound healing warrant further investigation.

Six‐year review of Acanthamoeba keratitis in New South Wales, Australia: 1997–2002

Aim: To assess the incidence and risk factors for Acanthamoeba keratitis (AK), the diagnostic interval, and the efficacy and outcome of current treatment among the population of New South Wales, Australia.

Prospective longitudinal study of corneal collagen cross-linking in progressive keratoconus.

Collagen cross‐linking has been reported to be effective in treating progressive keratoconus, and this study aims to evaluate the long‐term efficacy of this procedure.Background Collagen cross-linking has been reported to be effective in treating progressive keratoconus, and this study aims to evaluate the long-term efficacy of this procedure. Design Prospective longitudinal interventional study of patients with progressive keratoconus who underwent cross-linking in a tertiary referral hospital. Participants Thirty-five patients (51 eyes) who underwent cross-linking with a mean follow-up of 14.38 ± 9.36 months (range 6–48) were compared with a control group of 25 fellow eyes that did not undergo the procedure. Methods Cross-linking was performed using 0.1% riboflavin (in 20% dextran T500) and ultraviolet A irradiation (370 nm, 3 mW/cm2, 30 min). Main Outcome Measures Maximum keratometry in dioptres, logMAR best spectacle-corrected visual acuity, cylindrical power, manifest refraction spherical equivalent and central corneal thickness. Results Analysis of the treated group demonstrated a significant flattening of maximum keratometry by 0.96 ± 2.33 dioptres (P = 0.005) and a significant improvement in visual acuity by 0.05 ± 0.13 logMAR (P = 0.04). In the control group, maximum keratometry increased significantly by 0.43 ± 0.85 dioptres (P = 0.05), and visual acuity decreased by mean 0.05 ± 0.14 (P = 0.2). No statistical differences were noted regarding cylindrical power, spherical equivalent or corneal thickness in both groups. Conclusions Results indicate that corneal collagen cross-linking using riboflavin and ultraviolet A is effective as a therapeutic option in cases of progressive keratoconus by reducing the corneal curvature and by improving the visual acuity in these patients.

Corneal perforation associated with pellucid marginal degeneration and treatment with crescentic lamellar keratoplasty: two case reports.

Purpose: To describe 2 cases of corneal perforation associated with pellucid marginal degeneration (PMD) and subsequent successful management with crescentic lamellar keratoplasty. Methods: Two cases are discussed along with the relevant literature. Results: Both patients presented with spontaneous corneal perforations and associated features consistent with PMD. In both cases, there was fellow eye evidence of PMD, and 1 of the patients was already known to our unit with this diagnosis. Initial conservative measures were unsuccessful, and both patients underwent crescentic lamellar keratoplasty as the definitive surgical management with a good visual outcome. Conclusions: Crescentic lamellar keratoplasty is an effective technique for the management of this rare complication of PMD.

Comparative analysis of corneal measurements obtained from a Scheimpflug camera and an integrated Placido‐optical coherence tomography device in normal and keratoconic eyes

To assess the agreement between a Scheimpflug camera (Pentacam) and a combined Placido‐optical coherence tomography device (Visante OMNI) in measuring corneal curvature, thickness and elevation values in normal and keratoconic eyes.

Outcome of Corneal Collagen Crosslinking for Progressive Keratoconus in Paediatric Patients

Purpose. To evaluate the efficacy of corneal collagen crosslinking for progressive keratoconus in paediatric patients. Methods. This prospective study included 25 eyes of 18 patients (aged 18 years or younger) who underwent collagen crosslinking performed using riboflavin and ultraviolet-A irradiation (370 nm, 3 mW/cm2, 30 min). Results. The mean patient age was 14.3 ± 2.4 years (range 8–17) and mean followup duration was 20.1 ± 14.25 months (range 6–48). Crosslinked eyes demonstrated a significant reduction of keratometry values. The mean baseline simulated keratometry values were 46.34 dioptres (D) in the flattest meridian and 50.06 D in the steepest meridian. At 20 months after crosslinking, the values were 45.67 D (P = 0.03) and 49.34 D (P = 0.005), respectively. The best spectacle corrected visual acuity (BSCVA) and topometric astigmatism improved after crosslinking. Mean logarithm of the minimum angle of resolution (logMAR) BSCVA decreased from 0.24 to 0.21 (P = 0.89) and topometric astigmatism reduced from mean 3.50 D to 3.25 D (P = 0.51). Conclusions. Collagen crosslinking using riboflavin and ultraviolet-A is an effective treatment option for progressive keratoconus in paediatric patients. Crosslinking stabilises the condition and, thus, reduces the need for corneal grafting in these young patients.

Recovery from macular phototoxicity after corneal triple procedure

Purpose: Visual recovery from macular phototoxicity in 2 cases after prolonged exposure to operating microscope light from uncomplicated corneal triple-procedure surgery. Recovery is discussed in the context of repair and regeneration. Methods: Retrospective case reports. Results: Immediately postoperatively, both patients reported positive scotomata and were found to have macular retinal pigment epithelial depigmentation. In 1 case, the fovea was involved. By 6 to 12 months, the scotomata had disappeared despite large areas of retinal pigment epithelial hyperpigmentation remaining. Conclusion: Recovery from macular phototoxicity occurs, although the mechanism remains unclear. Positive scotomata in these cases resolved over several months. The time scale of recovery was consistent with the time required for cellular replacement and possible differentiation from neural progenitor cells.

Relationship of Structural Characteristics to Biomechanical Profile in Normal, Keratoconic, and Crosslinked Eyes.

Purpose: To evaluate the correlation of corneal biomechanical parameters with structural characteristics in normal, keratoconic, and collagen crosslinked eyes. Methods: A prospective observational study that included 50 normal, 100 keratoconic, and 25 crosslinked eyes. All eyes were imaged using a Scheimpflug camera and an ocular response analyzer. The main outcome measures analyzed were central corneal thickness (CCT), corneal volume (CV), maximal keratometry (Kmax), corneal hysteresis (CH), and corneal resistance factor (CRF). Results: Significant differences were noted among all 3 groups of eyes for CCT, CV, Kmax, CH, and CRF values (P < 0.05 by analysis of variance). CH and CRF correlated negatively (CH, r = −0.40; CRF, r = −0.44; both P < 0.0001) with the Pentacam topographic keratoconus classification. Both CH and CRF correlated positively with CCT and CV for the normal, keratoconic, and crosslinked eyes. In contrast, significant negative correlations were observed between CH, CRF, and Kmax in the keratoconic eyes (CH, r = −0.43; CRF, r = −0.53; both P < 0.0001), whereas no association was noted for the normal and crosslinked eyes. Conclusions: CH and CRF are influenced by the corneal structure, with higher values noted in corneas with greater thickness and volume. Corneal biomechanical parameters progressively decrease as the severity of keratoconus increases. After collagen crosslinking, the relationship of the corneal curvature to the biomechanical profile is similar to normal eyes.

Dapsone induced haemolytic anaemia in patients treated for ocular cicatricial pemphigoid

Ocular cicatricial pemphigoid (OCP) is a systemic autoimmune disease of unknown aetiology. It causes a chronic, scarring conjunctivitis and frequently affects other mucous membranes. Definitive diagnosis is made by immunofluorescent staining of conjunctival tissue demonstrating IgG, IgM, and or IgA in the basement membrane.1 Dapsone is an immunomodulating sulphonamide and has widely been used in the treatment of mild to moderate OCP.2–4 All patients treated with dapsone show varying …

Corneal collagen crosslinking for post-lasik ectasia: an Australian study

Purpose: Post laser‐assisted in situ keratomileusis (LASIK) ectasia is a rare and unpredictable complication after LASIK. Corneal collagen crosslinking (CXL) has emerged as a promising technique to address this complication. Our study evaluates the long‐term efficacy of CXL for post‐LASIK ectasia in an Australian setting. Design: Retrospective review of post‐LASIK ectasia patients referred to and treated at 3 corneal refractive surgery institutions in Sydney, Australia. Methods: Eleven patients (14 eyes; mean age, 39.7 ± 12.6 years) underwent epithelium‐off CXL with follow‐up ranging from 12‐78 months. Best spectacle‐corrected visual acuity (BSCVA), simulated keratometry, corneal topography indices, and higher‐order aberrations (HOAs) [mean ± standard error of the mean (SEM)] were measured with a rotating Scheimpflug camera (Pentacam, Oculus). Comparisons between baseline measurements and postoperative outcomes were performed using paired t test analysis. Results: At last follow‐up, BSCVA improved significantly by 0.2 ± 0.06 logMAR (P = 0.01), and 12 of 14 eyes showed no keratometric deterioration. Of the corneal topography indices, index of height asymmetry showed a trend toward a significant improvement (P = 0.05). There was no progression of corneal HOAs. Central corneal thickness was not significantly altered (P = 0.6). No major postoperative complications were observed. Conclusions: In the Australian setting, CXL has proven effective at stabilizing the progression of post‐LASIK ectasia, inducing corneal regularity, and improving visual acuity.