**10. Conclusion**

OCT has become a very valuable tool in the imaging of diabetic retinopathy. It is useful in the diagnosis of DME as well as decision-making regarding the treatment of DME. It is also helpful in following up the cases with DME after treatment with anti-VEGF therapy. It helps in diagnosing non-responders to treatment. It also provides information regarding the vitreoretinal interface and therefore helps decide the need for surgical intervention. It provides reliable qualitative information regarding retinal thickness. Various OCT-based classifications of DME have helped in better understanding of the disease pathogenesis. The evaluation of retinal layers on OCT explains the correlation between the retinal thickness at baseline and the final visual acuity achieved after treatment. The arrival of OCTA has further enhanced the imaging process. It adds to the information provided by SD-OCT or SS-OCT. It gives information regarding the blood supply of the retina, the density of the vessels, changes in the foveal avascular zone and helps to identify neovascular networks. It precludes the use of the invasive fundus fluorescein angiography and hence can be used in people with contraindications to fundus fluorescein angiography.

Thus, OCT has become a vital tool to diagnose and monitor the response of DME to various intravitreal pharmacotherapies including anti-VEGF agents.
