•DigiScope (EyeTel Imaging, Subsidiary of Advanced Diagnostics, Inc, Boston, MA): 1 field [11]

It has also been reported that a single-field

nonmydriatic monochromatic wide-field digital photograph of the disk and macula was more sensitive for diabetic retinopathy screening than mydriatic ophthalmoscopy, the currently accepted screening method [12].

13.11Is Mydriasis Needed While Using Nonmydriatic Camera?

Pupillary dilatation improves the gradability of a single-field 45° digital fundus image during telescreening of diabetic retinopathy. It was reported that after pupillary dilatation, the nongradability of digital fundus images reduced from 29.1% to 8.6% [13].

13.12Validation Studies on Telescreening

13.12.1 Accuracy of Telescreening

Kawasaki et al. reported that 92% of the diabetic patients were successfully evaluated for diabetic retinopathy using telemedicine as a screening tool [14]. Tennant et al. advocated telemedicine for screening of DR [15]. They used a stereoscopic fundus digital imaging technology, and they were able to identify microaneurysms, clinically significant and nonsignificant macular edema, neovascularization, and intraretinal microvascular abnormalities with great precision. The findings in this study were confirmed by direct examination when the patient was presented for treatment. Liesenfield et al. demonstrated 92% sensitivity and 81% specificity in identifying macular edema using two-field 50° nonstereo images in the study of telescreening of diabetic retinopathy [16]. We reported 79% agreement of telescreening for presence or absence of DR and 73% agreement for diagnosis of sight-threatening retinopathy [17].

13.12.2Patient Satisfaction in Telescreening

A patient satisfaction questionnaire was prepared to assess the prominent aspects of patient satisfaction in teleophthalmology screening. 44.4% respondents felt that telescreening was more satisfying than in person evaluation. Sixty percent felt that both models were equally satisfying. Patients who asked questions during the screening were 2.18 times more likely to be satisfied with teleophthalmology than those who did not ask any question [18, 19].

13.12.3 Cost Effectivity

Marberley et al. modeled the cost-effectiveness of diabetic retinopathy screening by comparing traveling retinal specialists and retinal photography with a portable digital camera. They concluded that the retinal camera was a relatively cost-effective screening method for diabetic retinopathy in isolated communities [20, 21].

The cost-effectiveness of such screening programs increased substantially if exams for diabetic retinopathy were combined with screening for other diseases that posed a risk to the same patient population [22]. Javitt et al. used a computer model, incorporating data from the various population-based studies and clinical trials from the multicenter studies to study the costeffectiveness of detecting and treating diabetic retinopathy [23–28]. The resulting analysis and projections indicated that preventive programs aimed at improving eye care for diabetic patients produced substantial savings. Hence, they were considered as highly cost-effective health investments for society. Diabetic retinopathy screening was considered to be more cost effective than any other routinely provided health interventions for diabetic patients.

Telescreening had a considerably lower cost per case when compared to the base hospital from the societal perspective. Based on the preliminary cost-effectiveness analysis, it was found that the cost per diabetic patient screened would be $3.84 with the mobile teleophthalmology screening.