title: Variations in human corneal endothelial cell morphology and permeability to fluorescein with age.
abstract: Fluorophotometry with topically applied fluorescein and endothelial cell photography were performed on 80 normal subjects (age 5-79 yr). Variations in endothelial cell morphology and function, flow of aqueous humor, and intraocular pressure were recorded. The mean endothelial cell size was 332.3 +/- 46.3 micron 2. A 28% increase in endothelial cell size was measured over the eight decades (r = 0.53, P less than 0.001). The coefficient of variation of cell size also increased with age (r = 0.41, P less than 0.001). The percentage of hexagonal endothelial cells decreased by 14% (r = -0.48, P less than 0.001), while the percentage of pentagonal and heptagonal cells increased by 50% (r = 0.44, P less than 0.001) and 40% (r = 0.33, P less than 0.002), respectively, with age. The mean endothelial permeability to fluorescein was 4.03 +/- 0.63 x 10(-4) cm min-1. A 23% increase in endothelial permeability with age was observed (r = 0.44, P less than 0.001). No change in central corneal thickness or endothelial pump rate was found. Flow of aqueous humor remained stable with age, despite a 25% increase in intraocular pressure (r = 0.50, P less than 0.001). Polarization of fluorescence of fluorescein in the corneal stroma decreased with age (r = -0.46, P less than 0.001). We conclude that with age the human corneal endothelium becomes morphologically less regular and may become more permeable to fluorescein.
authors.affiliation: Department of Ophthalmology, Mayo Clinic, Rochester, MN 55905.
authors.forename: K H
authors.initials: KH
authors.lastname: Carlson
authors.forename: W M
authors.initials: WM
authors.lastname: Bourne
authors.forename: J W
authors.initials: JW
authors.lastname: McLaren
authors.forename: R F
authors.initials: RF
authors.lastname: Brubaker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000867:Anterior Chamber; D001082:Aqueous Humor / Q000502:physiology; D002463:Cell Membrane Permeability; D002648:Child; D002675:Child, Preschool; D003319:Corneal Stroma / Q000502:physiology; D004728:Endothelium, Corneal / Q000166:cytology / Q000378:metabolism*; D005260:Female; D019793:Fluorescein; D005452:Fluoresceins / Q000493:pharmacokinetics*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged
chemical_list: D005452:Fluoresceins; D019793:Fluorescein