Test-retest variability of retinal nerve fiber layer thickness and macular ganglion cell-inner plexiform layer thickness measurements using spectral-domain optical coherence tomography.

PURPOSE: To evaluate the test-retest variability of spectral-domain optical coherence tomography (OCT) in measurement of retinal nerve fiber layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness. METHODS: A total of 65 eyes of healthy subjects were enrolled in this observational cross-sectional study. RNFL thickness and GCIPL thickness were measured using the repeat scan optic cube and macular cube protocol using Cirrus HD-OCT (software version 6.0). A single operator obtained 3 measurements during 1 session to determine test-retest variability. Intrasession repeatability was defined by intraclass correlation, limits of agreement, and coefficient of variation. RESULTS: The mean age of patients was 37.89±15.11 years (range, 10 to 70 y). The mean RNFL thickness readings as measured during 3 sessions were 93.89±9.73, 93.63±10.00, and 93.55±9.64 µm and average GCIPL thickness measurements were 82.90±4.61, 82.98±4.24, and 83.06±4.36 µm, respectively. Coefficient of variation was 1.2 for average RNFL thickness and 0.82 for average GCIPL thickness. The intraclass correlation coefficient showed a good correlation between repeat measurements for both average RNFL and GCC thicknesses (0.994 and 0.990, respectively). The limits of agreement (95% confidence interval) for the 3 sessions ranged from -3.61 to 4.13 µm for the average RNFL thickness and -2.55 to 2.40 µm for GCIPL thickness measurements. CONCLUSIONS: In healthy eyes, Cirrus HD-OCT shows excellent intrasession repeatability for RNFL and GCIPL thickness measurements.

Test retest variability of TonoPen AVIA.

The study was conducted to evaluate the intra-session repeatability of Tonopen AVIA (TPA). 180 eyes of 180 patients (50 eyes with glaucoma, 130 eyes of controls) were recruited for this observational study. The mean age of patients enrolled in the study was 43.9 ± 16.7 yrs (84 males, 96 females). Mean IOP recorded with Tonopen AVIA was 19.5 ± 9.5 mmHg, 19.4 ± 9.6 mmHg and 19.3 ± 9.2 mmHg, respectively in the first, second and third instances (P = 0.656). The intraclass correlation coefficient (ICC) ranged from 0.996 (95% CI: 0.956 - 0.998) for glaucoma subjects to 0.958 (95% CI: 0.934 - 0.975) for controls. The coefficient of variation in the study population ranged from 3.47% (glaucoma patients) to 8.10% (healthy controls), being 6.07% overall. The coefficient of repeatability varied between 2.96 (glaucoma patients), 3.35 (healthy controls) to 3.24 (overall). Thus, the Tonopen Avia shows good intrasessional repeatability of IOP in both glaucomatous patients and healthy subjects.

Femtosecond laser cataract surgery: technology and clinical practice.

The recent introduction of femtosecond lasers to cataract surgery has generated much interest among ophthalmologists around the world. Laser cataract surgery integrates high-resolution anterior segment imaging systems with a femtosecond laser, allowing key steps of the procedure, including the primary and side-port corneal incisions, the anterior capsulotomy and fragmentation of the lens nucleus, to be performed with computer-guided laser precision. There is emerging evidence of reduced phacoemulsification time, better wound architecture and a more stable refractive result with femtosecond cataract surgery, as well as reports documenting an initial learning curve. This article will review the current state of technology and discuss our clinical experience.

Surgical outcomes and safety of femtosecond laser cataract surgery: a prospective study of 1500 consecutive cases.

OBJECTIVE: To report the surgical outcomes and safety of femtosecond (FS) laser cataract surgery (LCS) with greater surgeon experience, modified techniques, and improved technology. DESIGN: Prospective, interventional case series. PARTICIPANTS: Fifteen hundred consecutive eyes undergoing FS laser cataract and refractive lens exchange surgery in a single group private practice. INTERVENTION: Femtosecond LCS. METHODS: All eyes undergoing LCS between April 2011 and March 2012 were included in the study. Cases underwent anterior capsulotomy, lens fragmentation, and corneal incisions with the Alcon/LenSx FS laser (Alcon/LenSx, Aliso Viejo, CA). The procedure was completed by phacoemulsification and insertion of an intraocular lens. The cases were divided into 2 groups: Group 1, initial experience consisting of the first 200 cases; and group 2, the subsequent 1300 cases performed by the same surgeons. MAIN OUTCOME MEASURES: Intraoperative complication rates and comparison between groups. RESULTS: Both groups were comparable for baseline demographic parameters. Anterior capsule tears occurred in 4% and 0.31% of eyes, posterior capsule tears in 3.5% and 0.31% of eyes, and posterior lens dislocation in 2% and 0% of eyes in groups 1 group 2, respectively (P<0.001 for all comparisons). Number of docking attempts per case (1.5 vs 1.05), incidence of post-laser pupillary constriction (9.5% vs 1.23%), and anterior capsular tags (10.5% vs 1.61%) were significantly lower in group 2 (P<0.001 for all comparisons). CONCLUSIONS: In the authors' experience, the surgical outcomes and safety of LCS improved significantly with greater surgeon experience, development of modified techniques, and improved technology.

Recalcitrant Pseudomonas keratitis after epipolis laser-assisted in situ keratomileusis: case report and review of the literature.

We report a case of recalcitrant microbial keratitis after epipolis laser-assisted in situ keratomileusis (epi-LASIK) surgery caused by Pseudomonas aeruginosa and review the literature on resistant Pseudomonas keratitis after excimer laser surgery. Microbial keratitis occurred two weeks after epi-LASIK surgery and was resistant to fluoroquinolones, aminoglycosides and macrolides but sensitive to meropenem. The patient had total corneal melting and required therapeutic penetrating keratoplasty. The globe could be salvaged and the distance visual acuity was 6/60 in the right eye. Recalcitrant Pseudomonas keratitis might require a therapeutic graft and necessitate the use of intravenous meropenem to prevent recurrence of infection.

Performance analysis of efforts towards promotion of corneal donation at a tertiary care trauma center in India.

PURPOSE: To identify the number of potential donors from trauma-related deaths and examine the extent of loss of opportunity at different levels for eye donation. METHODS: A retrospective review of the death records from the mortuary of Jai Prakash Narayan Apex Trauma Centre and National Eye Bank at All India Institute of Medical Sciences was conducted for the period between January 2008 and August 2009. All cases with trauma-related deaths were included in the study. Cases with known contraindications to eye donation were excluded from the study. The main outcome measure was "lost opportunity cases" where the families of eligible donors were not approached. The secondary outcome measure was successful procurement rate. RESULTS: The total number of trauma-related deaths noted during the study period was 1584. One hundred cases were excluded from the study because the records were either incomplete or not readily available. A total of 1066 cases were identified as medically suitable potential eye donors. The death-autopsy interval was 12 hours or less in 425 cases and >12 hours in 641 cases. Among eligible donors, there were 831 (78%) lost opportunity cases. Among 235 families approached, only 20 (8.5%) agreed to eye donation. Overall, successful eye donation was possible in only 20 (1.9%) of the eligible trauma-related deaths. CONCLUSIONS: Trauma-related deaths form a major pool for potential tissue donors. Only about one fifth of the medically eligible cases could be approached for counseling. A potentially large donor pool of trauma-related deaths is compromised by the lost opportunity cases and the low donation rate. Efforts are needed to augment existing administrative and manpower resources to increase the corneal procurement rate in the Indian population.

Fibrin glue-assisted fixation of decentered posterior chamber intraocular lens.

OBJECTIVE: To report the feasibility and outcome of the technique of glue-assisted fixation of decentered posterior chamber intraocular lens (PCIOL) in the posterior chamber using the same IOL. METHODS: The procedure was performed in three eyes having decentered PCIOL with inadequate capsular rim to support the IOL. The haptics were exteriorized under a partial thickness scleral flap at 1.5 mm behind the limbus and placed into a partial thickness scleral pocket and fixed with fibrin glue. No suture was placed at any site. RESULTS: On day 1 and at 6 weeks, the IOLs were well centered. There was no significant anterior or posterior segment inflammation, and the intraocular pressure was normal. CONCLUSION: Fibrin glue-assisted fixation of PCIOL is a feasible technique with good outcome in eyes with decentered IOL with inadequate capsular support.

Scrofuloderma and bilateral anterior staphyloma of eye: an unusual association.

We report a patient with bilaterally symmetrical perforated corneal ulcers with formation of anterior staphyloma associated with scrofuloderma. A 22-year-old female in her third month postpartum presented with multiple perforated corneal ulcers bilaterally. There was a presence of a skin lesion that was consistent with scrofuloderma. Fine needle aspiration cytology of preauricular lymph nodes showed evidence of granulomatous inflammation consistent with tuberculosis. Corneal scraping revealed the presence of coagulase-negative Staphylococcus. She was treated with topical fortified combination antibiotics (cefazolin and tobramycin). The corneal ulcer resolved with formation of anterior staphyloma in both eyes. The patient underwent anterior staphylectomy and tectonic keratoplasty in both eyes. Eight weeks postoperatively, her visual acuity improved to 20/200 in both eyes with clear grafts. Scrofuloderma may be associated with recurrent phlyctenulosis. Multiple corneal ulcerations coupled with use of topical steroids may result in corneal perforation and formation of anterior staphyloma.