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Related to Blue Sclera: osteogenesis imperfecta


see eyeeye,
organ of vision and light perception. In humans the eye is of the camera type, with an iris diaphragm and variable focusing, or accommodation. Other types of eye are the simple eye, found in many invertebrates, and the compound eye, found in insects and many other
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the external tough fibrous tunic of the eye, which performs a supportive and protective function. In most vertebrates the sclera contains cartilaginous tissue and bony laminae that form a sclerotic ring. (Chondrichthians and modern amphibians and mammals do not have sclerotic rings.)

In humans the sclera consists of a dense fibrous tissue in which intermixed collagenous and elastic fibers are arranged predominantly in meridional and equatorial directions. Connective tissue cells are located between the fibers, and pigment cells (melanocytes) are found where the optic nerve leaves the eye. The external layer of the sclera contains a highly motile system of slender collagenous fibers and laminae separated from one another by slitlike cavities (Tenon’s capsule); the fibers and laminae facilitate rotation of the eyeball in various directions. The external surface of the sclera is attached to the tendons of the oculomotor muscles.

In humans the thickness of the sclera at the posterior pole of the eyeball is approximately 1 mm, at the equator approximately 0.3–0.4 mm, and at the anterior pole of the eyeball at the site of the transition into the cornea approximately 0.6 mm. Small branching cavities are found at the junction of the sclera and cornea; the cavities join to form Schlemm’s canal, which drains fluid from the anterior chamber of the eye.



The hard outer coat of the eye, continuous with the cornea in front and with the sheath of the optic nerve behind.


the firm white fibrous membrane that forms the outer covering of the eyeball
References in periodicals archive ?
(2) Osteogenesis imperfecta patients present with multiple fractures; however, these are more severe than in pycnodysostosis, and have associated features such as choanal atresia and blue sclera. (1) Osteopetrosis also causes generalised osteosclerosis and increased bone density; however, the medullary cavities in the long bones are obliterated, and patients present with anaemia.
The spectrum of changes that have been reported are nystagmus, strabismus, microphthalmos, ptosis, blue sclera, pigmentation of the conjunctiva, corneal changes, cataract, optic atrophy, vitreous haemorrhage and myopia.
Examination of the eye revealed mi-crocornea, and blue sclera affecting the upper outer quadrants of both sclera.
The diagnosis of MS was established on the characteristics of tall stature, intermaxillary narrowness, myopia, retinitis pigmentosa, blue sclera, scoliosis, pectus excavatum, arachnodactyly and diminished ratio of Us/Ls.