Congenital Microphthalmia is a part of a spectrum of that begins with Anophathalmia result when there insult to embryo after outgrowth of optic vesicle. The condition may be associated with orbital cyst.
Microphthalmia may be unilateral or bilateral, can occur as an isolated disorder or associated with other ocular, craniofacial or systemic anomalies.
In older age group patient this disorder may result from surgery, trauma, inflammation, radiation and process that result in disorganisation of eye ball (phthiasis bulbi). In these patient small eye ball often associated with intra orbital calcification.
An eye with axial length less than 21mm in adult or less than 19mm in a year old child defined as Microphthalmia. In full term infants size of globe axial length measures 17.3mm. In a 2 year old child size of the globe is 90% of the adult (20-22mm)
On CT / MRI congenital Microphthalmia seen as small eye balls with poorly developed orbits.
The principle conditions in which Microphthalmia may be seen as an associated finding are:
Microphthalmia with orbital cyst.
Persistent hyperplasic primary vitreous.
Retinopathy of prematurity.
Post inflammatory herpes, cmv.
MIDAS syndrome (Microphthalmia, Dermal Aplasia, Sclerocornea)
Trisomy 13 and 18 syndrome.