Effect of overnight orthokeratology on conjunctival goblet cells

Effects of common eye diseases in children and their treatment measures on ocular surface homeostasis: A review

Ocular surface homeostasis plays a vital role in maintaining of eye health. Dry eye disease is one of the prominent and typical manifestations of disruption of ocular surface homeostasis that leads to the worsening of ocular surface homeostasis that leads to the worsening of ocular surface disease when it interacts with other pathogenic factors. However, disruption in ocular surface homeostasis in children is often overlooked because of the current methods of assessing ocular surface homeostasis. This review summarizes the main factors affecting ocular surface homeostasis in children, with the aim of drawing the attention of clinicians to the disruption of ocular surface homeostasis in children when dealing with such diseases. Ocular surface homeostasis involves several interrelated components, each of which plays a nonnegligible role in ocular surface homeostasis. Unlike adults, children have a stronger lacrimal gland secretion capacity and milder symptoms when there is a slight disruption of the ocular surface homeostasis. In addition, children's expressive abilities were weaker. Therefore, dry eye in children is often ignored by doctors and parents, and clinicians should pay more attention to the protection of ocular surface homeostasis when treating children with these diseases. Therefore, there is a need for diagnostic criteria for dry eye disease specific to children.

Influence of overnight orthokeratology on tear film and meibomian glands in myopic children: a prospective study

BACKGROUND

Orthokeratology lenses, which are worn overnight, are recommended for reducing myopia progression. They lie on the cornea and can influence the ocular surface by temporarily reshaping the corneal surface through a reverse geometry design. This study investigated the effect of overnight orthokeratology lenses on tear film stability and meibomian gland status in children aged 8-15 years.

METHODS

This prospective, self-controlled study included 33 children with monocular myopia who were prescribed orthokeratology lenses for at least one year. The experimental group (ortho-k group) comprised 33 myopic eyes. The control group comprised the emmetropic eyes of the same participants. Tear film stability and meibomian gland status were measured using a Keratograph 5M (Oculus, Wetzlar, Germany). Paired t-tests and Wilcoxon signed-rank tests were used to compare the data between the two groups.

RESULTS

At the one-year visit, the non-invasive first tear film break-up time (NIBUTf) values were 6.15 ± 2.56 s and 6.18 ± 2.61 s in the experimental and control groups, respectively. The lower tear meniscus height was 18.74 ± 0.05 μm and 18.65 ± 0.04 μm in these groups, respectively. No significant difference was observed in loss of meibomian glands or non-invasive average tear film break-up time between the experimental and control groups using Wilcoxon signed-rank tests.

CONCLUSIONS

The stability of the tear film and meibomian gland status were not significantly affected by wearing orthokeratology lenses overnight, indicating that continuous use of orthokeratology lenses for 12 months has a minimal effect on the ocular surface. This finding can help guide the clinical management of tear film quality with respect to the use of orthokeratology contact lenses.

Ocular signs and symptoms of orthokeratology patients associated with povidone iodine-based disinfecting solution

PURPOSE

To determine the frequency and severity of ocular symptoms and signs in new orthokeratology (ortho-k) subjects using a povidone iodine (PI) disinfecting system compared to those present before lens wear, and whether these were associated with cleaning regimes.

METHODS

This study recruited 80 subjects from two myopia control studies, who used a PI disinfecting solution for routine use. Ocular symptoms and signs at baseline, one- and six-month after lens wear were reported via questionnaires and ocular examination, respectively. To determine if rates of occurrence were attributable to differences in cleaning regime, subjects were randomly assigned into four groups with respect to routine care procedures, which involved various combinations of rubbing and use of a daily and/or enzymatic cleaner.

RESULTS

Sixty-eight subjects completed all aspects of the study. As there were no significant differences in incidence of signs and symptoms between the four groups before and after lens wear (Friedman tests, p > 0.07), data were combined for further analysis. Prior to lens wear, itchiness (69 %) and dryness (53 %) were the most commonly reported symptoms. The frequency and severity of all symptoms remained similar after lens wear (p > 0.10). Presence of follicles in the lower tarsal conjunctiva (22 %) and conjunctival injection (15 %) was frequently observed, but reduced significantly after lens wear (p < 0.01). Mild corneal staining, noted in 13 % of subjects at baseline, did not change significantly over time (p = 0.17). Ocular signs were not necessarily reflected in symptoms and vice versa.

CONCLUSION

Use of a PI-based solution did not increase the frequency or severity of ocular signs and symptoms observed before lens wear. Absence of a difference in occurrence of ocular discomfort with respect to cleaning regimes indicated that the use of the PI-based solution may adequately clean the lenses over a 6-month period.

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.

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.

Differences between Inferior and Superior Bulbar Conjunctiva Goblet Cells in Scleral Lens Wearers: A Pilot Study

SIGNIFICANCE

Scleral lenses (SLs) rest on the scleroconjunctival region, which could result in a mechanical impact in the bulbar conjunctiva that can hypothetically modify some properties of conjunctival cells.

PURPOSE

The purpose of this study was to evaluate the differences in goblet cell density (GCD) and mucin cloud amplitude (MCA) between superior and inferior bulbar conjunctiva in SL wearers.

METHODS

A total of 26 eyes wearing SL were randomly selected from 26 subjects (11 females) with different grades of keratoconus enrolled in a prospective clinical series. Superior and inferior conjunctival impression cytologies were performed and therefore analyzed with scanning laser confocal microscopy to evaluate GCD and MCA. All subjects filled out the Ocular Surface Disease Index (OSDI) questionnaire.

RESULTS

The mean ± standard deviation OSDI score was 23.62 ± 15.12. Although a higher density of goblet cells was observed in the samples taken in the superior conjunctiva (74.70 ± 57.55 cells/mm) than on the inferior conjunctiva (55.91 ± 34.80 cells/mm), there were no statistically significant differences between them (P = .14, Wilcoxon). Regarding MCA, no differences were found between superior (21.81 ± 3.30 μm) and inferior (20.72 ± 2.95 μm) samples (P = .201, Wilcoxon). No statistically significant differences were found in GCD and MCA regarding the time of SL wear.

CONCLUSIONS

There were no differences in GCD and MCA in the samples taken in the superior and inferior conjunctival areas. Also, it seems that the SL wearing time does not affect the density and secretion of goblet cells. Prospective studies need to be conducted in larger samples to confirm those outcomes.

Treating Uncomfortable Contact Lens Wear With Orthokeratology

OBJECTIVES

Many contact lens (CL) users permanently discontinue wear because of ocular dryness and discomfort. This study aimed to determine whether refitting symptomatic soft CL wearers in to orthokeratology could improve ocular symptoms and signs.

METHODS

This was a prospective, 3-month, open-label study of symptomatic (Contact Lens Dry Eye Questionnaire [CLDEQ-8] ≥12) soft CL wearers who were between the ages of 18 and 45 years. All subjects were refit into orthokeratology CLs (Emerald, Euclid Systems). The following tests were completed: CL history, Standardized Patient Evaluation of Eye Dryness (SPEED) questionnaire, CLDEQ-8, CLDEQ-4, logarithm of the minimum angle of resolution visual acuity, pupil size, refractive error, slit-lamp biomicroscopy, noninvasive tear break-up time, tear meniscus height, phenol red thread, conjunctival staining, corneal aesthesiometry, and corneal topography.

RESULTS

Twenty-nine of 40 qualifying subjects (age=24.43±4.62 years) completed the study. No significant differences were detected between completed and noncomplete subjects. Completed subjects had significantly better CLDEQ-8, CLDEQ-4, and SPEED scores at 3 months compared with baseline. Completed subjects had significantly better conjunctival staining scores and flatter keratometry values at 1 month compared with baseline.

CONCLUSIONS

Although not all symptomatic soft CL wearers were able to be refit into orthokeratology, subjects who were wearing orthokeratology at 3 months had a significant and clinically meaningful improvement in ocular symptoms. Additional work is needed to determine the mechanism leading to improved comfort because few clinical signs were changed after switching to orthokeratology.

Analysis of parental decisions to use orthokeratology for myopia control in successful wearers

PURPOSE

To investigate factors that influence parental decisions to use orthokeratology (ortho-k) as a myopia control method for their children, and parents' perspectives during children's ortho-k treatment in a hospital setting.

METHODS

Parents/guardians of children wearing ortho-k lenses for at least six months were required to complete a face-to-face survey to investigate the reasons for choosing ortho-k and their experience of the treatment.

RESULTS

Parents/guardians of 128 ortho-k wearers were recruited from the West China Hospital, Sichuan, China. The majority of the participants (74%) were mothers. Wearers' mean age at the time of the survey was 12.0 ± 2.0 years, with a mean history of ortho-k lens wear of 20.3 ± 8.0 months. Most participants had learned about ortho-k through word of mouth (56%) or from ophthalmologists (40%); in China, only ophthalmologists may prescribe ortho-k. The highest ranked motivation was the rapid progression of their children's myopia (54%), followed by ophthalmologists' advice (17%) or participants' who felt they had obtained enough knowledge (17%) of ortho-k (Kruskal-Wallis test, p = 0.002). 'Effectiveness' was the most common reason that participants decided to use ortho-k (81%), and potential injury was their major concern (75%). Itchy/sore eye was the most common initial adverse effect experienced with lens wear (22%), while a lost or broken ortho-k lens was the most frequently reported problem (34%). Parents of older lens wearers were significantly less involved in all procedures (Spearman rank correlation test, all p < 0.001). Most wearers, according to either the participants or the wearers themselves, were willing to wear ortho-k lenses at treatment commencement (80%), and the most common reason was 'to avoid having to wear spectacles in the daytime'.

CONCLUSIONS

The most powerful motivation for parents to enrol their children in ortho-k treatment was the rapid progression of myopia. The main reason why participants chose ortho-k, which most participants learned of by word of mouth, was the effectiveness of the treatment. During use, the most common symptom reported was itchy or sore eyes, but only initially. Children's willingness to participate is very important for successful ortho-k treatment; however, their motivation can be quite different from that of their parents. Ortho-k is a well-accepted option for myopia control in children.

Dry eye symptoms and signs in children wearing OK lenses for six months in China

BACKGROUND

This study aims to investigate symptoms of dry eye and signs of ocular surface disease in children with myopia during OK lens wear.

METHODS

A total of 68 subjects were prospectively managed with OK lens correction. These subjects were 8-14 years of age with myopia -0.50 to -5.00 dioptres of sphere and astigmatism of≤1.00 dioptres of cylinder. Patients with any ocular disease were ruled out from this study. All subjects completed a dry eye symptom questionnaire for OSDI scoring, corneal fluorescein staining, tear film break up time (TBUT) test and Schirmer's test I during the follow-up period. The follow-up period includes the primary visit (baseline), and at one day, one week, one month and six months after wearing the lens.

RESULTS

In terms of dry eye symptoms, we found that OSDI scores were significantly high after one day of wearing the lens (P<0.05). Additionally, TBUT values significantly decreased after one day (P<0.01) and one week (P<0.05) of wearing the OK lens. Corneal staining grade also significantly increased after one day and one week of wearing the OK lens. Furthermore, Schirmer's Test I values slightly, but not significantly, increased after one day and one week of wearing the lens. All variables returned to pre-wear levels at one month after wearing the lens, which remained stable up to six months of wearing the OK lens.

CONCLUSION

Our study is the first reveal that OK lens wear in children leads to dry eye symptoms and disturbs the tear film during the initial period of OK lens wear. However, this did not significantly interfere with tear secretion during the follow-up period.

Assessment of Tear Film and Bulbar Redness by Keratograph 5M in Pediatric Patients After Orthokeratology

OBJECTIVES

To assess the tear meniscus height (TMH), noninvasive tear breakup time (NITBUT), and bulbar redness in pediatric patients after orthokeratology (OK).

METHODS

Pediatric patients who underwent overnight OK between December 2014 and November 2017 were retrospectively investigated. According to the time of wearing, subjects were divided into three groups: 1-week, 1-month, and over 1-year. Age-matched subjects were recruited as a control group. Keratograph 5M was used to assess TMH, NITBUT-first, NITBUT-average, and bulbar redness score.

RESULTS

A total of 106 subjects aged from 7 to 15 years were included. Compared with control group, NITBUT-first was significantly lower in 1-week group (P=0.036) and NITBUT-average was significantly lower in 1-month group (P=0.019). Compared with over 1-year group, NITBUT-first was significantly lower in 1-week and 1-month groups (P=0.014, P=0.035, respectively), and NITBUT-average was significantly lower in 1-month group (P=0.022). Bulbar redness score was significantly lower in 1-month group than 1-week group (P=0.004). No significant difference in TMH was found between all groups. Significant correlation was found between NITBUT-first and NITBUT-average in all subjects (R=0.812, P<0.001). No other significant correlations were found between variables included TMH, NITBUT, bulbar redness score, or target correction.

CONCLUSIONS

As a noninvasive method, Keratograph 5M was easily to be applied on pediatric patients. The OK lens did not induce significant tear deficiency or bulbar redness, but might affect tear film stability in a short term after wearing.