Palpebral lobe of the human lacrimal gland: morphometric analysis in normal versus dry eyes

Abstract

AimTo study the morphological features of the palpebral lobe of the main lacrimal gland in normal and dry eyes.MethodsThis cross-sectional study included 25 healthy subjects and 83 patients with dry eye disease (DED). The aetiological groups of DED were cicatrising conjunctivitis (CC, n=35), evaporative dry eyes (EDE, n=25) and Sjogren’s syndrome (SS, n=23). The palpebral lobes in both eyes were evaluated using slit-lamp biomicroscopy and photography for size (exposed area in mm2), shape (convex or flat), presence of cicatrisation (scarring and/or symblepharon) and appearance of the overlying conjunctival vessels.ResultsThe palpebral lobes in the normal and EDE group were similar in terms of size (41.5±15.6 mm2 vs 39±12.2 mm2, p=0.203), convex shape (100%) and absence of cicatrisation or vascular engorgement (0%). However, as compared to normal controls, the size of the palpebral lobe was markedly reduced in the SS (27.9±12.3, p<0.0001) and CC (18.1±13.7, p<0.0001) groups. The size of the lobes was asymmetric in the CC group (p<0.0001) and differed significantly from the SS group (p=0.0003). Flat contour (79% vs 50%, p=0.0028), subepithelial scarring with or without symblepharon (52% vs 13%, p<0.0001) and engorged conjunctival vessels (96% vs 63%, p=0.00011) were seen in a significantly higher proportion of lobes in the CC as compared to the SS group.ConclusionThe morphological features of the palpebral lobe of the main lacrimal gland are significantly distorted in aqueous deficient dry eyes due to CC and SS; however, the lobes in patients with EDE are similar to normal eyes.