Collie Eye Anomaly
Collie eye anomaly (CEA) is a congenital, developmental defect id the eye
Collie eye is due to an abnormal development of the mesodermal (middle layer) tissues of the eye. This results in defects of the sclera, choroid, optic disk, retina and blood vessels of the retina. These defects can be very extensive and lead to blindness or they can be relatively minor and cause no visual deficits.
The most common form of CEA is choroidal hypoplasia (CH). This is a defect in the choroid or vascular system of the back of the eye. It can be seen in an ocular examination as a non-pigmented area beside the optic disk.
More severe cases of CEA usually have colobomas. In CEA, colobomas are depressions or excavations in the back of the eye and may involve the optic disk and/or area around opric disk. Partial od total retinal detachments may be present in some cases of CEA. These may be unilateral or bilateral and usually develop in young puppies and cause complete blindness. CEA is known hereditary disease and is due to an autosomal recessive gene.
Autosomal recessive heredity |
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