Columnar keratopathy: An early manifestation of limbal stem cell deficiency

Abstract

# Background/Purpose Stem cells of the corneal epithelium reside in the limbal palisades and associated limbal epithelial crypts. The limbus constitutes a barrier between the conjunctival and corneal phenotype of cells. When the limbal barrier is breached, stem cell deficiency (LSCD) results with conjunctivalisation of the cornea. The purpose of this study was to document an early manifestation of LSCD which is consistent and distinct across several causes of LSCD. # Methods Seventeen eyes of 11 consecutive patients with diverse known causes of LSCD were included. Patients were examined clinically with the slit lamp and fluorescein staining, and by in vivo confocal microscopy. All corneas were photographed with a slit lamp camera. Seven patients underwent in vivo confocal microscopy examination. # Results There were 6 males and 5 females. Six cases had bilateral involvement and the other 5 were unilateral. All patients showed predominantly superior loss of limbal anatomy with effacement of the palisades of Vogt, superficial vascularization encroaching on the peripheral cornea and alternating columns, 6–20 in number, of late fluorescein staining conjunctivalised and normal epithelium extending for a variable distance towards the corneal centre. These were related to prolonged contact lens wear, atopic keratoconjunctivitis, superficial ocular surface burns, ocular cicatricial pemphigoid, rosacea keratoconjunctivitis, old trachoma and neurotrophic keratopathy. In vivo confocal microscopy confirmed features of LSCD. # Conclusion Alternating columns of conjunctivalized and normal epithelia encroaching on the cornea from the superior limbus is a distinct manifestation of early LSCD across a diverse range of causes. The reason for this manifestation is unclear but could be related to the random dysfunction or loss of the palisade architecture.