What is Microphthalmia, Anophthalmia, Coloboma?

Anophthalmia (meaning “no eye”) is where no eye or eyes grow at all. It will just look as if the eyelids are closed.  

Microphthalmia (meaning small eye) is where the eye or eyes do not grow to full size, so are smaller than normal. The eye can also be cloudy or completely white and the pupil may be oddly shaped. 

Children with Anophthalmia may be given an artificial eye or eyes called a 'prosthesis' which looks like a normal eye or eyes. 

Most cases of Microphthalmia and Anophthalmia occur by chance and the cause is not known. However, it may be caused by changes in a baby’s genes which means the eye didn't form properly. Occasionally, other parts of the face and mouth may also not grow correctly too. 

Coloboma (pronounced col - a - bow - ma) means that part of one or more structures inside an unborn baby’s eye didn’t develop fully during pregnancy. This underdeveloped tissue is normally in the lower nasal (down and towards the nose) part of the eye and it can be small or large. A coloboma occurs in about one in 5,000 births and develops at around five to seven weeks of pregnancy. 

Coloboma can affect one eye (unilateral) or both eyes (bilateral) and it can affect different parts of the eye. As Coloboma forms during the initial development of the eye, it is present from birth and into adulthood. 

Further advice and support for those with Microphthalmia, Anophthalmia and Coloboma and their families can be found on the Microphthalmia, Anophthalmia & Coloboma Support (MACS) website. 

RNIB Specialist Advice Service Advisors can give further information on this topic