Epiretinal Membrane Peeling as the Treatment for Macular Edema Associated with Isolated Retinal Astrocytic Hamartoma.

PURPOSE: To report a case of macular edema and an epiretinal membrane in an isolated astrocytic hamartoma treated surgically. METHODS: Case report. RESULTS: We describe the case of a 37-year-old woman whose first symptoms were blurred vision and metamorphopsia. Optical coherence tomography revealed macular edema together with an epiretinal membrane secondary to an isolated retinal astrocytic hamartoma. We performed a pars plana vitrectomy (PPV) with membrane peeling. Both visual and structural outcomes were satisfactory. Complete resolution of symptoms was obtained, and visual acuity was preserved after a 7-month follow-up. CONCLUSION: Although rare, epiretinal membrane may be present in isolated retinal astrocytic hamartomas, PPV and epiretinal membrane peeling may be a good treatment option in glial tumors with macular edema associated with an epiretinal membrane.

Multicentre study: reliability and repeatability of Scheimpflug system measurement in keratoconus.

PURPOSE: To assess the repeatability and reliability of the most important tomographic parameters for characterising keratoconus measured with a Pentacam HR (high resolution). METHODS: Overall, 230 eyes in 158 patients with keratoconus were analysed. We performed five consecutive corneal tomography examinations for each eye with a Pentacam HR in patients with keratoconus. Study eyes were classified into three groups depending on the maximum posterior elevation (max_BFS_post): grade 1 for cases of keratoconus with a max_BFS_post of 40 µm; grade 2 for those with a max_BFS_post of between 41 and 75 µm and grade 3 for those with a max_BFS_post of over 75 µm. We calculated the intraclass correlation coefficients (ICCs) and repeatability limits of parameters from tomography and aberrometry. RESULTS: All the parameters were found to have excellent ICCs (0.9). The repeatability limits for the key parameters were higher than 0.5D for the power parameters, 20° for the axis of corneal astigmatism and 10 µm for the thinnest corneal thickness. Further, we obtained repeatability limits of above 0.1 µm for the aberrometry values and overall greater than 15° for the coma axis. All the values increase with the severity of keratoconus, except for that of the coma axis which falls with keratoconus grade. CONCLUSIONS: The reliability indicated by ICCs supports the view that the Pentacam HR is useful for the diagnosis of keratoconus. The repeatability limits suggest that new criteria should be established for monitoring progression taking into account the real measurements that can be made using this system.

Changes in the corneal thickness and limbus after 1 year of scleral contact lens use.

PURPOSE: To assess the physiological changes in the cornea over time in patients with irregular cornea fitted with Rose K2 XL gas-permeable scleral contact lenses. METHODS: Prospective study of 16 eyes of patients who did not tolerate gas-permeable corneal contact lenses and were fitted with Rose K2 XL scleral lenses. We assessed the central vault and the corneal thickness centrally and at peripheral regions (2 to 5 mm annulus). All these measures were obtained by anterior segment optical coherence tomography. The measurements were taken immediately after fitting the lenses and 1, 6 and 12 months later. Prior to the study and at 1 year, we performed an objective test for diagnosing limbal stem cell deficiency (Limbokit). RESULTS: The mean vault was 201.7 ± 82.3 µm 20 min after fitting the contact lens; 189.4 ± 94.0 µm at 1 month; 165.1 ± 75.9 µm at 6 months and 142.1 ± 76.8 µm at 1 year, the values at 6 and 12 months being significantly different to baseline. After 1 year, the central corneal thickness had increased by 2.3% (IQR = 5.6), but the changes were only significant for the superior thickness. There is no limbal stem cell deficiency after 1 year of scleral contact lens use. CONCLUSIONS: After use of Rose K2 XL scleral contact lenses, the corneal physiology of patients with an irregular cornea remains unchanged, as assessed by corneal thickness measurements and the Limbokit test. In all cases, however, the vault decreased over time.

Irregular Corneas: Improve Visual Function With Scleral Contact Lenses.

OBJECTIVES: To assess visual function in patients with irregular cornea who do not tolerate gas permeable (GP) corneal contact lenses and are fitted with GP scleral contact lenses (Rose K2 XL). METHODS: In this prospective study, we analyzed 15 eyes of 15 patients who did not tolerate GP corneal contact lenses and were fitted with scleral contact lenses (Rose K2 XL). We assessed visual function using visual acuity and the visual function index (VF-14); we used the VF-14 as an indicator of patient satisfaction. The measurements were taken with the optical correction used before and 1 month after the fitting of the Rose K2 XL contact lenses. We also recorded the number of hours lenses had been worn over the first month. RESULTS: Using Rose K2 XL contact lenses, visual acuity was 0.06±0.07 logMAR. In all cases, visual acuity had improved compared with the measurement before fitting the lenses (0.31±0.18 logMAR; P=0.001). VF-14 scores were 72.74±12.38 before fitting of the scleral lenses, and 89.31±10.87 after 1 month of lens use (P=0.003). Patients used these scleral lenses for 9.33±2.99 comfortable hours of wear. CONCLUSIONS: Both visual acuity and VF-14 may improve after fitting Rose K2 XL contact lenses in patients with irregular corneas. In addition, in our patients, these lenses can be worn for a longer period than GP corneal contact lenses.

Evaluation of the Reliability and Repeatability of Scheimpflug System Measurement in Keratoconus.

PURPOSE: To assess the reliability and repeatability of the parameters obtained using a Scheimpflug system (Pentacam HR-high resolution) for monitoring progression in eyes with keratoconus. METHODS: A prospective study was conducted based on measurements taken with the Pentacam HR in 82 eyes with keratoconus. We calculated the intraclass correlation coefficient (ICC) and the repeatability limit for topographic and aberrometric parameters. RESULTS: All the parameters analyzed had excellent ICCs, above 0.95 in all cases, except for the measurement of the anterior best-fit sphere, for which the ICC was 0.873. The key repeatability limits for the parameters analyzed were as follows: 1.54 diopters (D) for the maximum keratometry in the central cornea, 1.08 D for maximum keratometry, 32.6 degrees for the axis of corneal astigmatism, 11.9 degrees for the coma axis, and 14.2 µm for thinnest corneal thickness. CONCLUSIONS: The level of repeatability of the measurements obtained with a Pentacam HR confirms the usefulness of this system for the diagnosis of keratoconus. Nevertheless, it has certain limitations for monitoring individual progression of keratoconus and planning intrastromal corneal ring segment insertion.