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.