microphthalmia


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Related to microphthalmia: microphthalmia transcription factor

microphthalmos

 [mi″krof-thal´mus]
a developmental defect causing moderate or severe reduction in size of the eye.

mi·croph·thal·mos

(mī'krof-thal'mos),
Abnormal smallness of the eye.
[micro + G. ophthalmos, eye]

microphthalmia

A 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.

Aetiology
• 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.

Incidence
14/105; 3–11% of all cases of blindness.

microphthalmia

A congenital ↓ in eye size, with the ocular bulb measuring12 of the normal volume in extreme cases, due to an abnormal development of the optic vesicle in the optic cup, which may be
1. Congenital, as in encephalo-ophthalmic dysplasia, focal dermal hypoplasia, Hallermann-Streiff syndrome, incontinentia pigmenti, Lenz's microphthalmia syndrome, retinopathy of prematurity, trisomy 13-15 or.
2. Infectious–eg, CMV, rubella, toxoplasmosis. See TORCH.

microphthalmia

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.
Fig. M10 Right eye microphthalmos (From Kanski 2007, with permission of Butterworth-Heinemann)enlarge picture
Fig. M10 Right eye microphthalmos (From Kanski 2007, with permission of Butterworth-Heinemann)

mi·croph·thal·mos

, microphthalmia (mī'krof-thal'mŏs, -mē-ă)
Abnormal smallness of the eye.
[micro- + G. ophthalmos, eye]

microphthalmia

References in periodicals archive ?
Mutations at the mouse microphthalmia locus are associated with defects in a gene encoding a novel basic-helix-loop-helix zipper protein.
Although microphthalmia and abdominal wall defects have been associated with hyperthermia in human and animal studies (Edwards 2006; Graham et al.
Microphthalmia can affect vision in different ways.
Neonatal herpes usually results from infection of the newborn by virus secreted into the mothers' genital tract during labour and delivery, compared to rare cases of intrauterine infections, and ocular manifestations are conjunctivitis, keratitis, microphthalmia, cataract, iridocyclitis, iris dystrophy, optic neuritis, retinitis, and chorioretinitis (3).
Compared with MEB and WWS patients, the eye involvement in patients with FCMD is more variable, ranging from myopia to retinal detachment, persistent vitreous bodies, persistent hyaloid artery, or microphthalmia (156).
Peter, 40, a painter and decorator, has dedicated the past seven years to researching the effects of fungicides on children born with anophthalmia (no eyes) or microphthalmia.
About 33% of youths affected by congenital rubella have visual defects: Glaucoma - 4%, Cataracts - 20-50% (Krugman, 1965), Microphthalmia (under-sized eyes), or a type of Retinitis pigmentosa discussed below - 50%.
Continued patient enrollment as planned in the Phase 2 monotherapy trial with ARQ 197 in Microphthalmia Transcription Factor (MiT)-associated tumors;
The student, John (a pseudonym), had hearing impairment and cochlear implants; a visual diagnosis of microphthalmia, which enabled him to perceive shapes; and an exceptional intellectual ability that was recognized in school district-wide testing on multiple assessments in the third grade.
Microphthalmia transcription factor in the immunohistochemical diagnosis of metastatic melanoma: comparison with four other melanoma markers.
The article points out that congenital malformations of craniofacial structures comprise a significant class of birth defects such as cleft lip, cleft palate and microphthalmia, affecting more than 1 in every 600 births.
Originally prescribed as an antinausea agent in the 1960s, the developmental toxicity of the drug was discovered after thousands of tragic cases of skeletal appendicular malformations, microphthalmia, and fetal loss occurred in humans (Mellin and Katzenstein 1962).