Table 2.

Limitations of diabetic retinopathy screening

Limitation	Reason	Solution	References
Poor quality of images	Small pupil	Mydriasis	[9, 20, 36, 77]
	Poor transparency of optic media	Cataract extraction	[8, 9, 16, 18, 20, 75, 77, 79–82]
Screening program organizational problems	Need for trained photographers, graders and retina specialists	Training of technicians, nurses and general practitioners In-home testing with self-preliminary images reading AI grading	[7, 9, 10, 12, 13, 17, 18, 20, 22, 26–29, 33, 37–40, 42, 43, 45, 47–52, 55, 58, 59, 63, 65–68, 74–76, 76, 80–82]
High cost of screening	Expensive screening devices and software, crew costs	Mobile screening sets Cheap portable cameras Smartphone screening Telescreening AI-assisted screening	[9, 12, 23, 27, 33, 41, 43, 47, 58, 60, 64, 65, 67, 68, 73, 77, 81, 86]
Poor sensitivity of DR detection	1-, 2- or 3-field images- with too small coverage of retina	Ultra-wide fundus cameras use	[8, 9, 11, 15, 22, 23, 30, 33, 36, 39–42, 44, 46, 47, 49, 51, 57, 60, 61, 64–70, 75–77, 81, 82]
Low percentage of follow-up	Social and educational factors	Basic diabetic education	[19, 21, 23, 24, 34, 51, 86, 87, 89]
No positive results of telescreening	Small widespread in population	Diabetic education	[10, 11]
	Need for co-pay	Better social insurance
The more advanced the diagnosis, the more expensive	Expensive and complex screening schemes	Common use of AI	[39]
Long waiting time for final diagnosis	Insufficient screening system	AI grading	[9, 33, 38, 55, 68, 81]
Lack of an integrated virtual platform for DR screening	Lack of proper software	Development of screening software	[70]