Orthokeratology With a New Contact Lens Design in Hyperopia: A Pilot Study.

PURPOSE: To evaluate the preliminary clinical outcomes of a new contact lens design for orthokeratology in hyperopia. METHODS: Prospective pilot study including 8 hyperopic eyes of 4 nonpresbyopic patients (24-44 years) undergoing orthokeratology with the Alexa H contact lens (Tiedra Pharmaceutical, Madrid, Spain), which is an aspheric pentacurve design. Visual, refractive, corneal topographic, and aberrometric changes were evaluated during a 1-month follow-up. Likewise, the presence of ocular surface alterations was evaluated by slit-lamp biomicroscopy during this follow-up. RESULTS: Mean noncyclopegic sphere decreased significantly from a mean prefitting value of 2.94±0.95 D to mean values of 1.18±1.19 (P=0.01) and 0.25±0.85 D (P=0.04) at 1 week and 1 month of lens wear, respectively. Statistically significant changes were detected at 1 week of use of the lenses in keratometry (P=0.03), asphericity (Q) (P=0.01), and the Zernike term for corneal spherical aberration (SA) (P=0.01). However, no significant changes were observed in uncorrected (P=0.68) and best-corrected distance visual acuity (P=0.18). Superficial corneal staining was observed after the first night of use in only 1 patient who was resolved spontaneously. Likewise, the induction of a "toroid-like" topographic pattern leading to poor visual outcome and suboptimal correction was observed in four eyes at the beginning of the treatment. This condition was solved in all cases by reducing the lens diameter. CONCLUSION: The Alexa H lens seems to be useful for providing an orthokeratologic correction of hyperopia, with generation of increased negative Q and SA, and central steepening. However, fitting guides must be improved to avoid suboptimal outcomes as those related to the "toroid-like" topographic pattern defined.

Comparison Between Aberrometry-Based Binocular Refraction and Subjective Refraction.

PURPOSE: We evaluate the efficacy of a new system of binocular refraction, mainly based on ocular aberrometry (EYER) and compare it with the traditional subjective refraction as gold standard. METHODS: A prospective, double blind, and transversal study was performed on 99 subjects (35 men, 64 women; mean age 37.22 ± 18.04 years; range, 7-70 years). Refractive surgery or irregular cornea were considered exclusion criteria. Subjective refraction was performed by three different optometrists and EYER by other optometrists on three different days randomly. The binocular best corrected visual acuity (BBCVA), subjective vision evaluated with visual analogue scale (VAS), refraction spent time, and mean spherical equivalent (MSE), and vertical and oblique cylindrical components (J0 and J45) were analyzed. RESULTS: A positive strong correlation between EYER and subjective refraction was found for MSE (Pearson, 0.984; P < 0.001) and J0 and J45 (Pearson, 0.837; P < 0.001 and Pearson, 0.852; P < 0.001, respectively) in the total group. There were no statistically significant differences for BBCVA (P < 0.05). The VAS scores were 84.29 ± 12.29 with the EYER and 86.89 ± 12.38 with subjective refraction (P = 0.031). The spent time to perform the refraction was statistically lower (P < 0.05) with the EYER compared to conventional subjective refraction for all groups. CONCLUSIONS: The EYER system showed similar results in terms of spherical and cylindrical components, visual acuity being the spent time in the refraction lower than conventional subjective refraction. TRANSLATIONAL RELEVANCE: This new objective refraction system provides less chair spent time with similar results than subjective refraction.