LASIK monocular en pacientes adultos con ambliopía por anisometropía

ResumenObjetivoDeterminar la eficacia y la seguridad del LASIK en el tratamiento de la ambliopía por anisometropía en pacientes adultos.MétodosSerie de casos. Estudiamos a 12 pacientes adultos ambliopes por anisometropía a los cuales se realizó LASIK monocular de nuestro servicio de Córnea y Cirugía Refractiva. Evaluamos el error refractivo pre y postoperatorio, equivalente esférico (ES), la agudeza visual sin corrección (AVSC) y la agudeza visual mejor corregida (AVMC). La agudeza visual medida por la cartilla de Snellen fue convertida a LogMAR con fines de análisis estadístico.ResultadosLa edad promedio fue de 31.92 (± 12.13) años. El ES preoperatorio promedio en el ojo tratado fue de –3.49 D (± 3.24), el ES promedio del ojo no tratado fue de 0.25 D (± 0.30). La AVSC preoperatoria fue de 1.12 (± 0.3) LogMAR y la AVMC preoperatoria fue 0.31 (± 0.1) LogMAR. El seguimiento promedio fue de 19.1 (rango 6-74) meses. El ES promedio postoperatorio disminuyó a –0.28 (± 0.48). Cinco pacientes (42%) ganaron una línea de visión, un (8%) paciente ganó 2 líneas de visión y un (8%) paciente ganó 3 líneas de visión. El resto (42%) permaneció sin cambios comparados a la AVMC preoperatoria. Se encontraron diferencias estadísticamente significativas entre la AVSC preoperatoria (1.12 [±0.3]) y la AVSC postoperatoria (0.27 [±0.1]) (p=0.002, Z-Wilcoxon) y entre la AVMC postoperatoria (0.23 [±0.12]) y la AVMC preoperatoria (0.31 [±0.1]) (p=0.014, Z-Wilcoxon). No hubo complicaciones relacionadas con la cirugía.ConclusionesLa cirugía refractiva monocular en pacientes con ambliopía por anisometropía es una opción terapéutica segura y efectiva que ofrece resultados visuales satisfactorios, preservando o incluso mejorando la AVMC preoperatoria.AbstractPurposeTo investigate the efficacy and safety of LASIK for the correction of anisometropic amblyopia in adult patients.MethodsA retrospective, case series. We found 12 amblyopic adult patients that underwent monocular LASIK for anisometropía in our Cornea and Refractive service. We evaluated the preoperative and postoperative refractive error, spherical equivalent (SE), uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA). Snellen visual acuity measurements were converted to LogMAR for statistical purposes.ResultsThe mean age was 31.92 (±12.13) years. The average preoperative SE in the treated eyes was -3.49 (±3.24), the average SE of the untreated eye was 0.25(±0.30). Preoperative UCVA was 1.12 (±0.3) and average preoperative BCVA was 0.31 (±0.1). All patients had LASIK with an average follow-up time of 19.1(6-74) months. The average postoperative SE decreased to -0.28 (±0.48). Five patients (42%) gained 1 line of vision, 1 (8%) patient gained 2 lines of vision, 1 (8%) patient gained 3 lines of vision and the rest (42%) remained unchanged compared to preoperative BCVA. Statistically significant differences were observed between the preoperative UCVA [1.12 (±0.3)] with the postoperative UCVA [0.27 (±0.1)](p=0.002, Z-Wilcoxon) and between the postoperative BCVA [0.23 (±0.12)] with the preoperative BCVA [0.31 (±0.1)] (p=0.014, Z-Wilcoxon). There were no complications related to the surgical procedures.ConclusionsMonocular refractive surgery in adult patients with anisometropic amblyopia is a safe and effective therapeutic option that offers a satisfactory visual outcome, preserving or even improving the preoperative BCVA

Correlation of age, corneal curvature and spherical equivalent with central corneal thickness

Objective: To describe the distribution of the central corneal thickness (CCT) measurements on a healthy Hispanic sample population and its correlation with age, mean simulated keratometry (SimK), and mean refractive spherical equivalent (MRSE). Methods: Retrospective analysis on the records of healthy patients from the Ophthalmology and Visual Sciences Institute, Tecnologico de Monterrey, January 2015 to August 2015. CCT data, age, gender, corneal curvature, and spherical equivalent was obtained. A descriptive analysis and correlation by the Spearman method was performed. The sample was divided by age subgroups: than 40 years old and correlation analysis with CCT values was determined. Results: A total of 93 (186 eyes) patients were included. Mean age: 32.54 ± 12.04 years. 43% were women. Mean CCT: 545.69 ± 36.88 μm, mean SimK: 43.56 ± 1.90 D and MRSE: −2.54 ± 3.15 D. No correlation was registered between CCT and the variables when analyzed with the Anderson–Darling (p = 0.006), Shapiro–Wilk (p = 0.043), and Kolmogorov–Smirnov (p = 0.01). CCT showed a bimodal distribution with higher density at 540 μm. Age groups 40 years showed significant difference in CCT (p = 0.016), a positive correlation with CCT was observed in the group <20 (ρ = 0.596, p = 0.001). Conclusions: The findings regarding the lack of normality, the bimodal distribution (540 μm), and the correlation between age and CCT in younger patients, may lead us to redefine the “normal” CCT value in our population in order to be used properly for clinical purposes

Customizable Collagen Vitrigel Membranes and Preliminary Results in Corneal Engineering

Corneal opacities are a leading cause of visual impairment that affect 4.2 million people annually. The current treatment is corneal transplantation, which is limited by tissue donor shortages. Corneal engineering aims to develop membranes that function as scaffolds in corneal cell transplantation. Here, we describe a method for producing transplantable corneal constructs based on a collagen vitrigel (CVM) membrane and corneal endothelial cells (CECs). The CVMs were produced using increasing volumes of collagen type I: 1X (2.8 &mu;L/mm2), 2X, and 3X. The vitrification process was performed at 40% relative humidity (RH) and 40 &deg;C using a matryoshka-like system consisting of a shaking-oven harboring a desiccator with a saturated K2CO3 solution. The CVMs were characterized via SEM microscopy, cell adherence, FTIR, and manipulation in an ex vivo model. A pilot transplantation of the CECs/CVM construct in rabbits was also carried out. The thickness of the CVMs was 3.65&ndash;7.2 &micro;m. The transparency was superior to a human cornea (92.6% = 1X; 94% = 2X; 89.21% = 3X). SEM microscopy showed a homogenous surface and laminar organization. The cell concentration seeded over the CVM increased threefold with no significant difference between 1X, 2X, and 3X (p = 0.323). The 2X-CVM was suitable for surgical manipulation in the ex vivo model. Constructs using the CECs/2X-CVM promoted corneal transparency restoration