Using a povidone iodine (PI) solution does not increase the frequency or severity of ocular signs and symptoms observed prior to orthokeratology (ortho-k) lens wear, according to a study published in Contact Lens and Anterior Eye.
Researchers enrolled 80 children (mean age, 9.05±1.14 years; 66% girls) who wore ortho-k lenses in a study and randomized them to 1 of 4 groups using different cleaning regimes. All participants disinfected their lenses with the PI-based solution per the manufacturer’s instructions. Group 1 participants merely disinfected the lenses, but the remaining children all rubbed their lenses prior to disinfection. Group 2 individuals only rubbed their lenses with the PI-based solution. Children in group 3 used an additional daily cleaner and group 4 participants used both a daily cleaner and a weekly protein removal treatment. All participants rubbed and rinsed their lenses with the rinsing solution and use unpreserved artificial tears to cushion the lenses.
Study participants also completed a questionnaire to assess visual symptoms and symptoms related to lens wear, including discomfort, dryness, itchiness, burning sensation, redness, and tearing.
Investigators report no significant differences in signs and symptoms between the 4 groups before and after lens wear (P >.07). Prior to lens wear, itchiness (69%) and dryness (53%) were the most reported symptoms. A total of 8 children reported a burning sensation before lens wear, but it improved in 4 participants. The frequency and severity of all symptoms remained similar after lens wear (P >.10).
Follicles in the lower tarsal conjunctiva (22%) and conjunctival injection (15%) were commonly observed, but reduced following lens wear (P <.01). Mild corneal staining was observed in 13% of children at baseline, and did not change over time (P =.17).
“[T]here were no significant differences between the groups with respect to symptoms, indicating that the disinfecting solution adequately removed deposits without additional cleaning steps, probably due to the presence of a surfactant in the solution and/or a proteolytic enzyme incorporated in the neutralizing tablet,” according to the researchers. ”However, as deposits do tend to accumulate over time and ortho-k lenses are routinely replaced only on an annual, or even longer, basis, practitioners may wish to err on the side of caution and advise their patients accordingly.”
Study limitations include a short study duration, small sample size, and lack of a control group using an alternative solution.
References:
Cho P, Boost MV, Cheung SW. Ocular signs and symptoms of orthokeratology patients associated with povidone iodine-based disinfecting solution. Cont Lens Anterior Eye. doi:10.1016/j.clae.2022.101742