The back of the eye is examined with a variety of ophthalmoscopes, which give a stereoscopic and panoramic view of the tumour and its surroundings.



Picture showing the examiner performing binocular indirect ophthalmoscopy while comparing the tumour appearances with an old photograph. The use of transparencies has recently been superseded by digital photographs.


Most tumours can be diagnosed by their appearance on ophthalmoscopy or slit-lamp examination. It may be necessary to monitor a lesion over several months or years to detect growth, thereby confirming the diagnosis.

Difficulties can arise if the tumour is not visible because of haemorrhage or cataract. These can be overcome by treating the cataract, waiting for the haemorrhage to clear spontaneously, or perhaps removing the haemorrhage surgically.