Contact lens wear and the goblet cells of the human conjunctiva—A review

PurposeTo review the reported effects of contact lens wear on the goblet cells of the human conjunctiva.MethodsA literature search was undertaken to identify reports on the conjunctival health after contact lens wear, principally as assessed using the conjunctival impression cytology (CIC) technique in which cells are examined ex vivo, after fixation and staining. Details of technique, data on duration of contact lens wear and then CIC outcome in terms of goblet cell density (GCD) were extracted.ResultsOf 24 reports identified, 22 examined the bulbar conjunctiva and 2 examined the tarsal conjunctiva. A decrease in GCD was considered, directly or indirectly, to be a consequence of contact lens wear in 18 of the studies, but there was no obvious overall relationship between duration of lens wear and the GCD changes. Conversely, four reports indicated an increase in GCD or goblet cell-related mucins. Two reports concluded that there was no change in goblet cells or their mucin, a result however that is consistent with a recent conclusion that no statistically significant change in GCD was detectable in contact lens wearers assessed by in vivo imaging of the human conjunctiva by confocal microscopy.ConclusionsThe majority of published studies have concluded that contact lens wear results in a decrease in goblet cells in the conjunctiva. While there are reports that draw a very different conclusion, it should be noted that there has been limited consistency in technique or the method of reporting the results across the various studies.