Table 6.

Tele-ophthalmology Programs and Systems

		TELE-OPHTHALMOLOGY PROGRAM VALIDATION CATEGORY LEVELS
INTERNATIONAL CLASSIFICATION LEVEL OF DR	ETDRS LEVEL OF DR	CATEGORY 1 SYSTEMS IDENTIFY	CATEGORY 2 SYSTEMS IDENTIFY	CATEGORY 3 SYSTEMS IDENTIFY	CATEGORY 4 SYSTEMS IDENTIFY
No apparent DR	DR absent	No or minimal DR	Patients without sight-threatening DR or DME	No DR, NPDR, early and high-risk DR, and DME for follow-up and treatment strategies	All levels of DR or DME; photographs match, exceed, or can replace ETDRS photographs in any clinical or research program.
Mild DR	Very mild NPDR
Moderate NPDR	Moderate NPDR	More than minimal DR—but patients require additional screening
Severe NPDR	Severe NPDR, very severe NPDR		Patients with sight-threatening DR, NPDR, and PDR
PDR	PDR, High Risk PDR, Very Severe or Advanced PDR

DME, diabetic macular edema; DR, diabetic retinopathy; ETDRS, Early Treatment Diabetic Retinopathy Study (30°, stereo seven-standard field, color, 35-mm slides as reference); NPDR, nonproliferative diabetic retinopathy; PDR, proliferative diabetic retinopathy.