Achieving comfortable, all-day contact lens wear for dry eye patients can be quite a challenge. Often, dry eye patients who try wearing contact lenses report increased dry eye symptoms and limited comfortable wearing time. Although new soft and GP materials are being developed to help improve wettability and comfort during wear, remember to consider prescribing orthokeratology (ortho-k) for dry eye patients, because lenses are not worn during the day.
Clinically, patients using ortho-k often report how much more comfortable their eyes feel during the day compared to when they wore soft lenses. García-Porta et al (2016) compared ocular surface symptoms, as measured by the Dry Eye Questionnaire (DEQ), in a group of silicone hydrogel soft lens wearers compared to a group using ortho-k. The ortho-k wearers reported significantly less symptoms of dryness and discomfort at the end of the day. In addition, bulbar redness, limbal redness, and conjunctival staining were less with the ortho-k wearers than with the silicone hydrogel wearers, so the ortho-k wearers’ eyes looked better as well.
In addition, this subjective improvement results in increased vision-related quality of life; in studies using validated questionnaires, ortho-k users have better quality-of-life scores. The attributes included clarity of vision, activity limitations, symptoms (dryness, itching, etc.), dependence on correction, worry, appearance, confidence, self-image, and overall satisfaction with vision/vision correction (Lipson et al, 2005; Queirós et al, 2012; Santodomingo-Rubido et al, 2013; Berntsen et al, 2006; and others. Full list available at www.clspectrum.com/references .).
Studies of the ocular surface point to reasons for these subjective improvements in comfort. Carracedo et al (2016) showed minimal changes in the tear film in eyes of ortho-k wearers. Even though this study reported an increase in goblet cell density (GCD) and a better Ocular Surface Disease Index (OSDI) score after one month of ortho-k, it did not show a change in tear volume or in tear breakup time (TBUT). Another study (Xie et al, 2018) showed no significant tear deficiency or bulbar redness in ortho-k wearers after one week of wear.
Tear osmolarity is an objective indicator of dry eye. Nieto-Bona et al (2018) showed a slight increase in tear osmolarity one month after starting ortho-k, but it returned to normal in the following weeks.
Finally, Xiu et al (2019) found normal function of the meibomian glands with ortho-k.
Ortho-k provides patients with excellent vision, better daytime comfort than with daytime contact lens wear, and freedom from vision correction devices during the day. In dry eye patients, it can be challenging to provide comfortable contact lens wear for more than a few hours. When considering contact lens options for dry eye patients, keep in mind that both patient responses and clinical studies show improved comfort in ortho-k lenses versus soft lenses. Ortho-k lenses worn only while sleeping provide good vision all day without the need for correction. For dry eye patients, the most comfortable contact lens during the day may be no lens at all. CLS
For references, please visit www.clspectrum.com/references and click on document #284.