Tear film surface quality is reduced in children following orthokeratology (orthoK) treatment, but returns to baseline levels following a cessation period of 1-month, according to a study published in Contact Lens and Anterior Eye.
Researchers included 267 eyes from 145 children (mean age 11.0±2.8 years, 42.8% boys) in a retrospective study. They analyzed participants with myopia who were treated with orthoK for more than 1 year between March 2015 and August 2016. The team included measurements of tear film disruption (TFD) and central tear film disruption (cTFD) at baseline and during follow-up visits conducted at 1-day, 1-week, 2-week, 1-month, 3-month, 6-month, and 12-month intervals. They assigned both measurements a nominal value from 0 (perfect) to 1 (poor) and compared tear film surface quality before and after orthokeratology treatment.
At 1-day follow-up, TFD and cTFD significantly increased (t =-17.3 and t =-10.4, respectively, P <.001 for both), and investigators note the consistency of the change through to the 12 month follow-up ( F =51.1, and F =28.0, respectively, P <.001 for both).
Investigators also analyzed 2 subsets of participants for comparative data. One subset consisted of 11 children who discontinued treatment for 1-month before being refit with orthoK lenses of a different design. The researchers found a significant increase in TFD compared with pre-orthoK scans (0.172±0.161), but this returned to baseline levels after lens cessation (0.084±0.059). Analysis of another subset of 23 monocular orthoK lens wearers revealed that TFD and cTFD increased in eyes that wore monocular lenses, but remained stable in the lateral eyes.
Researchers note the temporary reduction in tear film quality and advise, “It is of importance to ensure tear film surface quality is continuously monitored throughout use of orthoK lenses.”
Study limitations include a retrospective nature, single-center design, and failure to record corneal punctate staining grades and times.
Guo Y, Liu L, Peng L, Fu J, Guo W, Tang P. Effect of overnight orthokeratology lenses on tear film stability in children. Cont Lens Anterior Eye. Published online April 4, 2022. doi:10.1016/j.clae.2022.101592