Precorneal tear film after corneal collagen cross-linking in keratoconus

Purpose: To study the condition of precorneal tear film in keratoconus patients after corneal collagen cross-linking (CXL).

Material and methods: The study enrolled 24 patients (30 eyes) with stages I-III progressive keratoconus. All study patients underwent standard (Dresden) protocol CXL. Patients were examined before the surgery and 1 week, 1 month, and 3 months postoperatively. The condition of precorneal tear film was evaluated based on the results of Norn test (the tear film break-up time), Schirmer test, Jones test, optical coherence tomography based lacrimal meniscometry, and improved tearscopy.

Results: One month after CXL, patients with keratoconus experienced transient changes in the precorneal tear film condition – the tear film break-up time was reduced, the tear secretion was elevated, the lacrimal meniscus biometry parameters were increased, and the thickness of the tear film lipid layer was decreased.

Conclusion: Corneal changes resulting from CXL lead to transient disorders of the mucin and lipid layers of the precorneal tear film, which requires adequate tear substitute therapy in the postoperative period.

Keywords: cross-linking; dry eye; keratoconus; tear film.

Voronin GV, Bubnova IA, Averich VV, Sarkisova KG. Sostoyanie prekorneal’noi sleznoi plenki posle krosslinkinga rogovichnogo kollagena pri keratokonuse (predvaritel’noe soobshchenie) [Precorneal tear film after corneal collagen cross-linking in keratoconus (preliminary report)]. Vestn Oftalmol. 2021;137(5. Vyp. 2):224-230. Russian. doi: 10.17116/oftalma2021137052224. PMID: 34669331.