Meibomian gland atrophy in Keratoconus: A case-control study

PurposeTo assess the Meibomian Gland Atrophy (MGA) in keratoconus patients by comparison to healthy controls.SettingFrench Keratoconus national reference center, Bordeaux, France.DesignObservational, monocentric, comparative case control study.MethodsEighty-eight keratoconic eyes free of any surgical treatment (KC group) and 88 healthy eyes (NKC group) matched for age and gender, included from December 2018 to May 2019, underwent infrared meibography providing a meiboscore of MGA (primary outcome measure), scaled from 0 to 6. Secondary outcomes including Lipid Layer Thickness (LLT) assessment using interferometry, Tear Break-Up Time (T-BUT) evaluated by a slit lamp examination, corneal OCT-based topography, and two dry eye questionnaires (OSDI and SPEED) filled by the patients during the consultation.ResultsA significant difference in distribution of meiboscore scores between groups (p < 0.0001 for total, superior and inferior meiboscore) was found, with lower scores in controls compared to eyes with keratoconus. Using a cut-off value of ≥2 as abnormal meiboscore, 64.8% of eyes of cases had abnormal meiboscore by comparison to only 27.3% of controls (OR, 4.91; 95%CI, 2.56 to 9.38). Patients with keratoconus had higher OSDI (mean difference 15.3, 95%CI 1.8 to 1.7) and SPEED (mean difference 2.5, 95%CI 2.5 to 4.5) results. No significant difference was found in T-BUT whereas keratitis was more common in cases.ConclusionKeratoconus was associated with higher meibomian gland atrophy in this study.