Abstract
Purpose: :
Apart from laser treatment, several new therapeutic agents have been developed for the treatment of diabetic macular edema (DME) in the recent years. However, it is not clear how the information originating from clinical trials can be used for a treatment decision in an individual case of diabetic macular edema in daily clinical routine and if there are differences in the treatment response according to specific morphologic alteration. For this reason, a new grading system for DME was defined.
Methods: :
110 eyes showing DME were examined using 2 different spectral domain optical coherence tomography (SD OCT) devices (Cirrus©, Carl Zeiss Meditec, and Spectralis OCT©, Heidelberg Engineering) and by performing a fluorescence angiography (FA) of the central and peripheral retina (Spectralis HRA, Heidelberg Engineering). Results were evaluated for characteristic imaging findings that influence the treatment decision in a clinical setting, and based on these findings a grading protocol was generated. In the next step, all OCT and FA images were evaluated by 3 blinded readers in order to evaluate the repeatability of the generated grading system.
Results: :
Giving respect to possible treatment decisions, the evaluation of the OCT and FA images revealed 4 types of diabetic macular edema: Edema secondary to vitreoretinal traction, focal or generalized edema in OCT secondary to focal leakage in FA, generalized edema in OCT secondary to generalized leakage in FA, generalized or focal edema in combination with central or peripheral ischemia. Each of these edema types was further specified by characteristic morphologic details. The generated grading protocol allowed for precise description of the individual amount of retinal alteration showing a significant inter-observer reproducibility between the 3 blinded readers.
Conclusions: :
A novel grading protocol for diabetic macular edema based on 2 imaging techniques was generated allowing for an exact description of the amount of alteration secondary to diabetic vasculopathy. As the main focus was to indicate a possible treatment decision, this grading protocol could be used in a clinical setting, as well as for further specifying inclusion criteria or evaluating a treatment response in a clinical trial.
Keywords: diabetic retinopathy • imaging/image analysis: clinical • retina