Table 3 Definition of overall image quality for all images from a given eye
From: Grading fluorescein angiograms in malarial retinopathy
Image quality | Definition |
|---|---|
Good | Focus and clarity are sufficient for grading of all features to be completed |
Retinal details (small capillaries) are sharply defined and have crisp boundaries. It should be possible to see the ends of the larger vessels approaching the foveal avascular zone (FAZ), if they are not obscured by pathology | |
Fair | The image is less well focused (than good), with it becoming more difficult to determine the ends of the larger vessels approaching the FAZ |
Retinal details are slightly fuzzy but subtle lesions, such as small retinal haemorrhages, can still be seen and graded | |
Poor gradeable | The image is less well focussed (than fair), but it is possible to glean some information for grading |
Clarity is decreased so that subtle lesions might be missed, but is sufficient for assessment of large retinal haemorrhages and large retinal vessels | |
Poor ungradeable | This should be selected if the grader is unable to evaluate or distinguish (with more than 50 % confidence) the absence or presence of any feature in all of the available images |