Note disease’s culmination in pink colour of part of the eye (7)

'of part of the eye' is the definition.
(I've seen this in another clue)

'note disease's culmination in pink colour' is the wordplay.
'note' becomes 'n' (abbreviation).
'disease's culmination' becomes 'e' (I can't explain this - if you can you should give a lot more credence to this answer).
'in' is an insertion indicator.
'pink colour' becomes 'coral' (I've seen this before).
'n'+'e'='ne'
'ne' inserted within 'coral' is 'CORNEAL'.

Can you help me to learn more?