The Change of Subfoveal Choroidal Thickness After Intravitreal Injection of Ranibizumab and Its Correlation With Visual Acuity in Diabetic Retinopathy

Diabetes is a metabolic disorder affecting the ocular vasculature. Although the principal posterior segment changes in diabetes usually occur in the retinal vasculature, additional changes are also observed in the choroid which provides an important blood supply to the outer retina. Diabetic choroidopathy involves choroidal abnormalities occurring in diabetic patients and may participate in mechanisms that lead to the decrease of visual acuity.

Several studies demonstrated the possibility of imaging of the choroid using spectral-domain OCT. Many studies investigated variation in the choroidal thickness (CT) occurring with changes in age and axial length, or in different ocular diseases, Diabetic macular edema (DME) is a major cause of visual loss in diabetic patients.

OCT (Optical coherence tomography) is a non-invasive imaging technique, that was used to obtain a high definition segments of retina. Lately, EDI (enhanced depth imaging) spectral-domain OCT has been explained. (EDI) program routinely captures a cross sectional picture with the choroid near the zero delay line to enhance sensitivity on the external edge of the choroid.

Functional imaging findings also presented a decrease in choroidal flow of the blood in eyes with diabetic retinopathy.

The current purpose of (EDI-OCT), which employing the enhanced depth of field from the inverted picture by locating the OCT device near to the eye, has helped the researchers to study the anatomic variations in the choroid in diabetic eyes.