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Related to nanophthalmos: Microphthalmos
abnormal smallness in all dimensions of one or both eyes in the absence of other ocular defects; see microphthalmos.
Abnormal smallness of the eye.
[micro + G. ophthalmos, eye]
microphthalmiaA congenital reduction in eye size, with the ocular bulb measuring 1/2 of the normal volume in extreme cases, due to an abnormal development of the optic vesicle in the optic cup.
• Congenital—e.g., encephalo-ophthalmic dysplasia, focal dermal hypoplasia, Hallermann-Streiff syndrome, incontinentia pigmenti, Lenz microphthalmia syndrome, retinopathy of prematurity, trisomy 13-15.
• Infectious—e.g., CMV, herpes, rubella, toxoplasmosis.
• Toxins—e.g., foetal alcohol syndrome.
14/105; 3–11% of all cases of blindness.
Congenital anomaly in which the eyeball is abnormally small and often deeply set in a small orbit. It is typically hyperopic. Syn. microphthalmos; microphthalmus. When there is no other abnormality (e.g. coloboma of the iris, microphthalmos with cyst), the condition is called nanophthalmos (Fig. M10). See anophthalmia; monophthalmia; pseudoptosis.