Treating Uncomfortable Contact Lens Wear With Orthokeratology

The clinical impact of contact lens wear on neural structure and function of the cornea

Contact lens (CL) use is growing rapidly, with a current estimate of over 100 million wearers worldwide. Vast improvements in materials and designs have occurred over the past decades with advancements in the understanding of ocular surface health with CL wear. However, the potential impact of CL on neural structures and function of the ocular surface, particularly in relation to the richly innervated cornea, remain poorly understood. Problems with sensation such as CL discomfort and conditions that may be associated with lens wear including dry eye disease also remain pervasive. This narrative review discusses the findings from studies involving soft or rigid CL wearers, assessed with c linical techniques designed for examining the neural integrity of the cornea, namely in vivo confocal microscopy and esthesiometry. While the collective findings remain equivocal in terms of the changes in corneal nerve morphology and function with conventional CL wear, more specialised CLs, namely orthokeratology lenses, which mechanically manipulates the structure of the cornea seem to produce more prominent changes in nerve distribution and sensitivity reduction. Given the intricate relationship between neural and immune mechanisms in maintaining balanced ocular surface health, the potential links between these structural and functional findings with parainflammation and neuroinflammation, as well as clinical issues including CL discomfort and dry eye disease, are also explored.

Analysis of Treatment Discontinuation in Orthokeratology: Studying Efficacy, Safety, and Patient Adherence Over Six Months

PURPOSE

This study aimed to evaluate the efficacy, safety, and participant compliance of orthokeratology treatment for the correction of myopic refractive errors over a six-month prospective study and to define the potential reasons for early treatment discontinuation.

METHODS

A total of 32 participants with low-to-moderate myopia were fitted with the spherical model of corneal refractive therapy (CRT) orthokeratology lenses (Paragon Vision Sciences) and followed over six months, with specific attention to alterations in refractive error, corneal topography, and epithelial thickness. Concurrently, participant feedback and reasons for any treatment discontinuation were documented.

RESULTS

Significant changes in refractive error and in corneal topography were observed, with approximately 50% of the refractive error being corrected on the first night of use and 100% by the first two weeks ( P <0.001). Central epithelial thickness experienced substantial thinning, reducing to 15.65±4.49 μm (67.38%) ( P <0.001) after 6 months of lens use. Six participants withdrew from this study for varied reasons, including unmet visual expectations and difficulty adhering to the lens-wearing regimen. Notably, the dropout group exhibited higher baseline low-order aberrations and less prolate corneas than those who persisted with the treatment ( P <0.05).

CONCLUSIONS

Orthokeratology with CRT is efficacious and safe for the correction of low-to-moderate myopia in adults, but a portion of patients discontinue the treatment in the first 6 months of contact lens wear. Special care should be taken when recommending orthokeratology in patients with higher levels of myopia and corneas with less prolate shape, providing more realistic expectations and even changing to dual axis or more sophisticated designs.

Orthokeratology in adults and effect on quality of life

OBJECTIVE

To determine changes in various ocular parameters of adults wearing orthokeratology (ortho-k) lenses and their levels of satisfaction and quality of life (QoL) after commencing treatment.

METHODS

Adults aged 18-38 years, with mild to moderate myopia and astigmatism < 1.50D, were wearing ortho-k lenses for one year. Data collection, which included history taking, refraction, axial length (AL), corneal topography, corneal biomechanics, and biomicroscopy examination, was performed at baseline and every 6 months during the study period. The level of satisfaction with the treatment and QoL was determined via questionnaires.

RESULTS

Forty-four subjects completed the study. AL was shortened significantly at the 12-month visit: AL -0.03 (-0.45 to 0.13) mm compared to baseline (p < 0.05). A significant number of subjects in both groups presented with overall and central corneal staining, but the majority were mild (Grade 1). Central endothelial cell density was reduced by 40/mm² (loss rate 1.4 %) (p < 0.05). High scores were obtained in the satisfaction questionnaire, with no significant differences between visits. At the 12-month visit, NEI-RQL-42 total score, dependence on correction, activity limitation, appearance, and satisfaction with the treatment all significantly increased compared to baseline values.

CONCLUSIONS

Results suggest that ortho-k can be an effective and safe myopia correction technique for adults with low to moderate myopia, improving daytime vision without serious adverse events. Satisfaction with ortho-k lens wear was high, particularly those who were dependent on vision correction and found spectacles or contact lenses limiting specific activities or cosmetically undesirable.

Quality of Life in Digital Device Users Who are Treated with Systane Hydration PF

PURPOSE

To understand the impact of Systane Hydration PF on dryness symptoms and quality of life in digital device users and to determine if participants prefer either the unit-dose or multi-dose dispensing system of Systane Hydration PF.

MATERIALS AND METHODS

This 2-week, three visit study recruited regular digital device users. Participants were required to score ≤80 on the Impact of Dry Eye on Everyday Life (IDEEL) Quality of Life (QoL) Work domain and between 13 and 32 on the Ocular Surface Disease Index (OSDI) questionnaire. Participants were randomized to either Systane Hydration PF unit-dose or multi-dose for 1 week and switched to the alternative dosing system for the second week. Participations were evaluated by completing the full IDEEL-QoL module and OSDI questionnaire at each visit. Likert surveys were completed to probe dispensing system preferences.

RESULTS

Thirty participants with a mean ± SD age of 28.6 ± 12.0 years (70% female) were recruited. Participants had significant improvements in all three IDEEL-QoL domains as well as in OSDI scores (all p < 0.0001). Participants had similar preferences for the two dispensing systems, though they were more likely to indicate that they thought that the multi-dose bottle was more environmentally friendly than the unit-dose vials.

CONCLUSION

Digital device users with dry eye symptoms had meaningful improvements in eye comfort and quality of life scores after being treated with Systane Hydration PF for 2 weeks. Participants did not have a clear dispensing system preference suggesting that the best dispensing system may depend on the patient.

Orthokeratology Lens Wear for 2 Years in Children Did Not Alter Tear Film Lipid Thickness by Non-Invasive Interferometry

Purpose

Previous studies suggest that overnight orthokeratology (OOK) may be detrimental to tear function. We aimed to investigate the effect of OOK on lipid layer thickness (LLT), blink pattern, and meibomian gland and elucidate the relationship of these variables.

Methods

Thirty-seven participants who wore OOK lenses every night for at least 2 years and twenty-four healthy non-contact lens wearers (controls) were enrolled in this retrospective study. LipiView interferometry, blink pattern analysis, the ocular surface status, and morphology and function of the meibomian gland were determined.

Results

The OOK group and healthy controls had similar LLT, blink patterns, ocular surface status, and the function of the meibomian gland. OOK participants demonstrated higher meiboscore in the lower eyelids (p < 0.05) but not in the upper eyelids. Within the OOK group, LLT was significantly impacted by the partial blink rate (p < 0.05) and the total score of the upper meibomian gland (p = 0.10).

Conclusions

Wearing OOK for 2 or more years increased lower eyelid meibomian gland dropout but did not have a reduction of LLT.

Compression Factor and Visual Performance in Adults Treated With Orthokeratology

OBJECTIVES

To investigate the effect of compression factor on visual performance in orthokeratology (ortho-k).

METHODS

Myopic adults were fitted with ortho-k lenses with either a 0.75 diopter (D) or 1.75 D compression factor. Higher-order aberrations (HOAs), corneal topography, and responses to the National Eye Institute/Refractive Error Quality of Life Instrument-42 questionnaire were measured at baseline and 6-month and 12-month follow-up along with a satisfaction questionnaire. Subjective refraction, high-contrast, and low-contrast visual acuity were measured at baseline and 1-day, 1-week, 6-month, and 12-month follow-up.

RESULTS

Forty-four myopic (mean spherical equivalent refraction: -3.66±0.84 D) adults (median age 25 years) completed the 12-month follow-up. After ortho-k lens wear, levels of satisfaction of vision after waking were significantly higher than vision before sleep for both compression factors (both P<0.01). The increased compression factor (ICF) resulted in less myopia at the 1-week visit (P=0.04) and better high-contrast unaided visual acuity at the 1-day visit (P=0.03) compared with the conventional compression factor (CCF). No other significant differences were observed for the compression factor for treatment zone diameter, lens decentration, or any subjective measurements. Individual HOA terms , , , and were significantly higher in the CCF group (0.75 D) (all P<0.05). The HOA visual Strehl ratio decreased significantly after lens wear (P<0.001) but did not vary with the compression factor.

CONCLUSIONS

An ICF did not result in clinically significant differences in subjective refraction, visual acuity, unaided vision, or the total ocular HOA profile compared with a CCF (0.75 D) in myopic adults after long-term ortho-k lens wear.

Established soft contact lens wearers' awareness of and initial experiences with orthokeratology

OBJECTIVES

To understand the initial awareness of and experience with orthokeratology in a group of adult, symptomatic, soft contact lens (CL) wearers.

METHODS

This was a prospective, 3-month, open-label study of symptomatic soft CL wearers who were between the ages of 18 and 45 years. Baseline measurements were taken and then all subjects were treated with orthokeratology. A dry eye evaluation was completed at baseline prior to orthokeratology treatment. This same dry eye evaluation was completed 1 week and 1 month after orthokeratology treatment. An investigator-designed questionnaire that aimed to understand the subject's initial awareness of and experience with orthokeratology was also administered at the baseline, 1-week, 1-month and 3-month visits (perceptions, knowledge, tolerance and ability to apply and remove orthokeratology lenses).

RESULTS

Twenty-nine out of 40 subjects completed this study. Completed subjects (age = 24.28 ± 3.75 years) had significant improvements in ocular comfort over the course of the study compared to their soft CLs. Most subjects were unfamiliar with orthokeratology before the study, were able to quickly adapt to the treatment and were likely to recommend orthokeratology to friends or children for myopia management.

CONCLUSIONS

This study found that few subjects knew about orthokeratology before learning about it through this investigation, suggesting that patients should be offered this treatment more regularly. This conclusion is supported by the ability of the subjects to learn and adapt to orthokeratology with ease, and their likelihood to recommend it to a friend or child.