Felipe Márquez, GemaNombela Palomo, MaríaPalomo Álvarez, CatalinaCacho Bobillo, IsabelNieto Bona, Amelia2023-06-172023-06-172017-010721-832X10.1007/s00417-016-3554-0https://hdl.handle.net/20.500.14352/18026Received: 19 April 2016 /Revised: 7 August 2016 /Accepted: 7 November 2016 /Published online: 21 November 2016Purpose: To analyze the binocular function changes produced on subjects undergoing overnight orthokeratology (OK) treatment over short-term (3 months) and long-term (3 years) wear. Methods: A prospective, longitudinal study on young adult subjects with low to moderate myopia was carried out. Binocular function was assessed by the following sequence of tests: Distance and near horizontal phoria (Von Graefe technique), distance and near horizontal vergence ranges (Risley rotary prisms), accommodative convergence/accommodation (AC/A) ratio (gradient method) and the near point of convergence (standard push-up technique). The short-term sample consisted of: 21 subjects in the control group, 26 in a corneal refractive therapy (CRT) treatment lenses group and 25 in a Seefree treatment lenses group. Those subjects were evaluated at baseline and at a 3-month follow-up visit. Twenty one subjects were old CRT wearers that attended a 3-year follow-up visit (long-term group). Results: A statistically significant difference over the 3-month treatment was found for divergence at distance: the break point decreased 1.4 Δ (p = 0.0006) in the CRT group and the recovery point increased 1.2 Δ (p = 0.001) in the Seefree group. Also, the Seefree group had an exophoric trend of 2.3 Δ at near (p = 0.02) and a base-out break decrease of 2.3 Δ (p = 0.03). For the long-term group, only the base-out break point at distant vision showed a statistically significant difference of 4.9 Δ (p = 0.02). Conclusions: OK induces minimal changes in the binocular function for either short-term or long-term periods, apart from a near exophoric trend over the short-term period.engjournal articlehttps://doi.org/10.1007/s00417-016-3554-0https://link.springer.com/article/10.1007/s00417-016-3554-0https://www.ncbi.nlm.nih.gov/pubmed/27873014restricted access617.7-089.243617.713-089Binocular functionContact lensesFusional vergencesMyopiaOrthokeratologyPhoriaLentes de contactoOptometríaÓptica oftálmica3311.11 Instrumentos ópticos2209.15 Optometría