Ocular surface analysis in young myopic patients sheds light on orthokeratology suitability
Children seeking orthokeratology treatment exhibit changes in tear secretion and an increase in meibomian gland deficiency as they age, according to a study.
The research also suggests that the diagnostic criteria for dry eye syndrome in adults may be applicable to orthokeratology candidates aged 12-18 years, although lower thresholds might be needed for younger candidates.
The study retrospectively examined children with myopia who were considered candidates for orthokeratology lens wear. The participants were categorized into 3 age groups. The researchers employed advanced diagnostic tools, specifically the Keratograph 5M and LipiView interferometry, to measure non-invasive tear meniscus height (TMH), non-invasive tear film break-up time (NIBUT), conjunctival hyperemia redness score (RS), meibomian gland loss (MGL) score, lipid layer thickness (LLT), and blink pattern analysis, which included the number of partial blinks (PB) and total blinks (TB), as well as the partial blink rate (PBR).
The study involved 1119 children with myopia (2070 eye), aged between 7 and 18 years. The mean TMH, NIBUT, and LLT among the subjects were measured at 0.21 mm, 12.45 seconds, and 65.28 nanometers, respectively. Additionally, the mean RS, upper MGL, and lower MGL scores were 0.64, 1.00, and 1.06, respectively, while the mean PB, TB, and PBR were 5.13, 6.46, and 0.81, respectively.
Age was found to be significantly associated with all ocular surface parameters, except for PB. NIBUT and LLT did not display significant differences between male and female participants. However, TMH, RS, and upper and lower MGL were notably higher in male participants compared to their female counterparts.
NIBUT was positively associated with TMH and LLT, while upper and lower MGL were positively correlated with TMH, PB, and TB; upper MGL exhibited negative correlations with NIBUT and LLT, while TB was negatively correlated with NIBUT and LLT. PB displayed no significant relation with TMH, NIBUT, and LLT. PBR, however, showed positive correlations with NIBUT and LLT, but not with TMH, RS, or MGL.
The study found that 57% of participants had a TMH of ≤0.2 mm, 43.2% had an NIBUT of ≤10 seconds, 48.1% had an LLT of ≤60 nanometers, and 88.1% had a PBR >0.4.
Reference
Yang Y, Wu Q, Pan W, Wen L, Luo Z, Wu H, Ran G, Yang Z, Li X. Characteristics of the Ocular Surface in Myopic Child Candidates of Orthokeratology Lens Wear. Ophthalmol Ther. 2023;doi: 10.1007/s40123-023-00793-y. Epub ahead of print. PMID: 37665499.
