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There is often confusion as to the role of the ophthalmoscope in
assessing the front of the eye and the red reflex and this is exemplified
in this article.
The red reflex can be performed from a metre away which is very useful in
small children. From a distance, both eyes can be compared. The value on
the ophthalmoscope can vary but is usually between 0 and +2. I have sent
posters to local GPs to explain how this is performed.
The +10 setting is useful to assess the anterior segment at which point
the ophthalmoscope acts as a magnifier. The instrument needs to be 10cm
from the eye. Cataracts and posterior synechiae can be demonstrated using
+10. Assessing the red reflex with a +10 is not easy.
No competing interests
17 November 2009
M Ashwin Reddy
Consultant Paediatric Ophthalmologist and Retinoblastoma Surgeon
Royal London Hospital, Whitechapel Road, London E1 1BB