Effect of overnight orthokeratology on conjunctival goblet cells

• Impression cytology is a good tool to evaluate the tear physiology in contact lens wearers.
• Goblet cell density and dry eye symptomatology improves during orthokeratology treatment in silicone hydrogel contact lens wearers.
• Orthokeratology could be a good alternative for contact lens discomfort and dryness.

ObjectiveTo evaluate the differences between goblet cell density (GCD) and symptomatology after one month of orthokeratology lens wear.MethodsA pilot, short-term study was conducted. Twenty-two subjects (29.7 ± 7.0 years old) participated voluntarily in the study. Subjects were divided into two groups: habitual silicone hydrogel contact lens wearers (SiHCLW) and new contact lens wearers (NCLW). Schirmer test, tear break up time (TBUT), Ocular Surface Disease Index (OSDI) questionnaire and conjunctival impression cytology. GCD, mucin cloud height (MCH) and cell layer thickness (CLT) were measured. All measurements were performed before orthokeratology fitting and one month after fitting to assess the evolution of the changes throughout this time.ResultsNo differences in tear volume and TBUT between groups were found (p > 0.05). However, the OSDI score was statistically better after one month of orthokeratology lens wear than the baseline for the SiHCLW group (p = 0.03). Regarding the goblet cell analysis, no differences were found in CLT and MCH from the baseline visit to the one month visit for the SiHCLW compared with NCLW groups (p > 0.05). At baseline, the GCD in the SiHCLW group were statistically lower than NCLW group (p < 0.001). There was a significant increase in GCD after orthokeratology fitting from 121 ± 140 cell/mm2 to 254 ± 130 cell/mm2 (p < 0.001) in the SiHCLW group.ConclusionOrthokeratology improves the dry eye subject symptoms and GCD after one month of wearing in SiHCLW. These results suggest that orthokeratology could be considered a good alternative for silicone hydrogel contact lens discomfort and dryness.