Descemet's membrane

Descemet's membrane
Vertical section of human cornea from near the margin. (Waldeyer.) Magnified. 1. Epithelium. 2. Anterior elastic lamina. 3. substantia propria. 4. Posterior elastic lamina. (Descemet's membrane) 5. Endothelium of the anterior chamber. a. Oblique fibers in the anterior layer of the substantia propria. b. Lamellæ the fibers of which are cut across, producing a dotted appearance. c. Corneal corpuscles appearing fusiform in section. d. Lamellæ the fibers of which are cut longitudinally. e. Transition to the sclera, with more distinct fibrillation, and surmounted by a thicker epithelium. f. Small bloodvessels cut across near the margin of the cornea.
Latin	l. limitans posterior corneae
Gray's	subject #225 1008

Descemet's membrane is the basement membrane that lies between the corneal proper substance, also called stroma, and the endothelial layer of the cornea. It is composed of a different kind of collagen (Type IV)^[1] than the stroma. The endothelial layer is located at the posterior of the cornea. Descemet's membrane, as the basement membrane for the endothelial layer, is secreted by the single layer of squamous epithelial cells that compose the endothelial layer of the cornea.

Its thickness ranges from 3 μm at birth to 8-10 μm in adults.^[2]

It is also known as the Posterior limiting lamina, posterior elastic lamina, lamina elastica posterior, and membrane of Demours. It was named after French physician Jean Descemet (1732–1810).

The corneal endothelium is a single layer of squamous cells covering the surface of the cornea that faces the anterior chamber.

Significant damage to the membrane may require a corneal transplant as the endothelial cells depend on it for support and cannot re-grow after injury without it.^{[citation needed]}

See also

• Kayser-Fleischer ring
• Pierre Demours

References

Histology A text and atlas. Michael H.Ross and Wojciech Pawlina 5th Edition 2006

1. ↑ "Medscape: Medscape Access". Emedicine.medscape.com. 2013-02-14. Retrieved 2013-09-14. 
2. ↑ Johnson DH, Bourne WM, Campbell RJ: The ultrastructure of Descemet's membrane. I. Changes with age in normal cornea. Arch Ophthalmol 100:1942, 1982

External links

• BU Histology Learning System: 08002loa
• Descemet membrane at the US National Library of Medicine Medical Subject Headings (MeSH)
• Diagram at dryeyezone.com

v t e Sensory system – visual system – globe of eye (TA A15.2.1–6, TH 3.11.08.0-5, GA 10.1005) Fibrous tunic (outer) Sclera Episcleral layer Schlemm's canal Trabecular meshwork Cornea Limbus layers Epithelium Bowman's Stroma Descemet's Endothelium Uvea/vascular tunic (middle) Choroid Capillary lamina of choroid Bruch's membrane Sattler's layer Ciliary body Ciliary processes Ciliary muscle Iris Stroma Pupil Iris dilator muscle Iris sphincter muscle Retina (inner) Layers Inner limiting membrane Nerve fiber layer Ganglion cell layer Inner plexiform layer Inner nuclear layer Outer plexiform layer Outer nuclear layer External limiting membrane Layer of rods and cones Retinal pigment epithelium Cells Photoreceptor cells (Cone cell, Rod cell) → (Horizontal cell) → Bipolar cell → (Amacrine cell) → Retina ganglion cell (Midget cell, Parasol cell, Bistratified cell, Giant retina ganglion cells, Photosensitive ganglion cell) → Diencephalon: P cell, M cell, K cell Muller glia Other Macula Foveola Fovea centralis Parafovea Perifovea Optic disc Optic cup Anterior segment Anterior chamber Aqueous humour Posterior chamber Lens Capsule of lens Zonule of Zinn Posterior segment Vitreous humour Other Asthenopia Keratocytes Ocular immune system Tapetum lucidum M: EYE anat (g/a/p)/phys/devp/prot noco/cong/tumr, epon proc, drug (S1A/1E/1F/1L)