Biomaterial Database

Scanning electron microscopy of posterior polymorphous corneal dystrophy. 1980

F M Polack, and W M Bourne, and S L Forstot, and T Yamaguchi

An 8 1/2-year-old girl had posterior polymorphous dystrophy that required keratoplasty. Similar lesions were found in the patient's mother, thus establishing the genetic trend of the disease. Scanning electron microscopy studies showed areas of endothelial cell degeneration and multiple depressions or pits. These seemed the most advanced and characteristic lesions of posterior polymorphous dystrophy. Transmission electron microscopy studies in areas adjacent to the pits showed an abnormally developed Descemet's membrane covered by two or more layers of elongated endothelial-like cells. Cells over Descemet's membrane seemed to deposit some Descemet's membrane material and both fine and coarse collagen fibrils. Cells had prominent mitochondria, normal endoplasmic reticulum, and desmosomal attachments. Cytoplasmic fibrils and microvilli were usually found in cells lining the anterior chamber. Specular microscopy and scanning electron microscopy recorded the image of only the innermost cells and these appeared as endothelium.

UI	MeSH Term	Description	Entries
D008853	Microscopy	The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.	Compound Microscopy,Hand-Held Microscopy,Light Microscopy,Optical Microscopy,Simple Microscopy,Hand Held Microscopy,Microscopy, Compound,Microscopy, Hand-Held,Microscopy, Light,Microscopy, Optical,Microscopy, Simple
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D003315	Cornea	The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)	Corneas
D003317	Corneal Dystrophies, Hereditary	Bilateral hereditary disorders of the cornea, usually autosomal dominant, which may be present at birth but more frequently develop during adolescence and progress slowly throughout life. Central macular dystrophy is transmitted as an autosomal recessive defect.	Corneal Dystrophies,Granular Dystrophy, Corneal,Groenouw's Dystrophies,Macular Dystrophy, Corneal,Stromal Dystrophies, Corneal,Corneal Dystrophy,Corneal Dystrophy, Hereditary,Corneal Granular Dystrophies,Corneal Granular Dystrophy,Corneal Macular Dystrophies,Corneal Macular Dystrophy,Corneal Stromal Dystrophies,Corneal Stromal Dystrophy,Dystrophy, Corneal,Dystrophy, Corneal Granular,Dystrophy, Corneal Macular,Dystrophy, Corneal Stromal,Dystrophy, Hereditary Corneal,Groenouw Dystrophies,Groenouws Dystrophies,Hereditary Corneal Dystrophies,Hereditary Corneal Dystrophy,Stromal Dystrophy, Corneal
D003886	Descemet Membrane	A layer of the cornea. It is the basal lamina of the CORNEAL ENDOTHELIUM (from which it is secreted) separating it from the CORNEAL STROMA. It is a homogeneous structure composed of fine collagenous filaments, and slowly increases in thickness with age.	Lamina Elastica Posterior,Descemet's Membrane,Descemet Membranes,Descemets Membrane,Elastica Posterior, Lamina,Elastica Posteriors, Lamina,Lamina Elastica Posteriors,Membrane, Descemet,Membrane, Descemet's,Membranes, Descemet,Posterior, Lamina Elastica,Posteriors, Lamina Elastica
D004727	Endothelium	A layer of epithelium that lines the heart, blood vessels (ENDOTHELIUM, VASCULAR), lymph vessels (ENDOTHELIUM, LYMPHATIC), and the serous cavities of the body.	Endotheliums
D005260	Female		Females
D005808	Genes, Recessive	Genes that influence the PHENOTYPE only in the homozygous state.	Conditions, Recessive Genetic,Genetic Conditions, Recessive,Recessive Genetic Conditions,Condition, Recessive Genetic,Gene, Recessive,Genetic Condition, Recessive,Recessive Gene,Recessive Genes,Recessive Genetic Condition