This is the macular OCT (ocular coherence tomography) of a 70 year old woman attending the diabetic clinic. Her visual acuity is 6/9 in both eyes. Early bilateral nuclear sclerosis are evident in both eyes. 

a. The area that taken by the OCT is within 500um of the fovea. What does the picture show?

Answer
Thickening of the retina with cystic spaces suggestive of macular oedema.

 

b. Clinically you can not detect any macular oedema despite the picture above. Should the patient have focal argon laser?

Answer
By definition the patient has significant macular oedema. While 
significant macular oedema is a clinical diagnosis it can be difficult 
to detect in patients with cloudy media such as cataract. Also early
macular oedema may be difficult to detect with indirect ophthalmoscope, a better visualization may be achieved with fundus contact lens in uncertain cases. 
 

c. Another diabetic patient has had recurrent vitreous haemorrhage despite repeated pan-photocoagulation. Fundoscopy reveals a persistent peripheral neovascularization. How can OCT help in further management?

Answer
Vitreous haemorrhage may result from pulling of vitreous on the 
peripheral neovascularization. This may be difficult to visualize 
clinically but detectable with an OCT. In such cases, the treatment
of choice is vitreoretinal surgery instead of repeat photocoagulation.
 

End of  viva 6