When a picture is taken of a child and the flashlight turns the eyes red, both eyes should be the same shade of red. If one eye lacks the red in the photograph, or if the red is a different shade between the two eyes, there could be an abnormality.
But double flashes and cameras which eliminate red-eye have taken away one of the tell-tale signs of cataracts and eye cancers.
Dr Justin Mora said New Zealand had screening programmes at birth and in pre-school, but the family photo album was sometimes used to pick up eye abnormalities.
"The red-eye reflect is a useful tool; the technology that removes it has taken one of our little tricks."
Mora said anyone who lacked the red-eye reflect in one eye should have their eyes examined.
In the two-hour operation at Auckland Eye in Remuera for little Benjamin, Mora used microscopic "cutting and sucking" tools to remove the cataracts.
Without the surgery, Benjamin would have been blind within a year.
The visit and urgent surgery was funded by a Canadian Christian charity which flew the family from Vanuatu and organised for an Auckland couple to host the family.
"We have been looked after so well," Benjamin's grandfather Alick Daniel said.
