The recommendations that follow summarize the content of the guideline. Please refer to the original guideline document for more detailed recommendations. Each recommendation is rated based on the level of the evidence and the grades of recommendation. Definitions of the level of evidence (Ia-IV) and the grades of recommendations (A, B, C, and GPP) are defined at the end of the Major Recommendations field.
Detection and Screening for Diabetic Retinopathy
Detection of Diabetic Retinopathy
C - As patients with sight-threatening retinopathy may not have symptoms, life-long evaluation for retinopathy by fundal screening of diabetic patients is a valuable and necessary strategy (American Academy of Ophthalmology Quality of Care Committee, 1993; Kohner & Porta, 1991; American Diabetes Association, 1998; Aiello et al., 1998). (Grade C, Level IV)
Screening for Diabetic Retinopathy
C - It is commended that organization of the screening for diabetic retinopathy be the primary responsibility of the doctor-in-charge of the diabetic patients (Kohner & Porta, 1991). (Grade C Level IV)
GPP - Screening may be performed by fundal photography (preferred method), indirect ophthalmoscopy with slit-lamp biomicroscopy, or direct ophthalmoscopy through dilated pupils. In Singapore, fundal photography has been used for many years. The fundal photography facility should be made widely available to all medical practitioners who wish to send their patients for diabetic retinopathy screening. (GPP)
GPP - Patients with fundi that are poorly visualized due to media opacity should be referred to the ophthalmologist. (GPP)
Screening strategies depend on the rate of appearance and progression of diabetic retinopathy and on the risk factors that alter these rates. The recommended schedule for the initial and follow-up examinations is outlined in the table below.
Table. Eye Examination Schedule
Condition |
Recommendation of 1st Exam |
Routine Minimum Follow-Up |
Type 1 DM |
Within 3 to 5 years of diagnosis of diabetes |
Yearly |
Type 2 DM |
At diagnosis |
Yearly |
Pregnancy in pre-existing DM |
Prior to conception and during 1st trimester |
Physician's discretion depending on results of 1st trimester exam |
Adapted from American Diabetes Association Clinical Practice Recommendations 2004 (Fong et al., 2004)
Classification of Retinopathy
C - All diabetic patients who are found to have retinopathy by their physicians need to be referred to an ophthalmologist for evaluation (American Academy of Ophthalmology Quality of Care Committee, 1993; Kohner & Porta, 1991; American Diabetes Association, 1998; Aiello et al., 1998).
(Grade C, level IV)
See original guideline document for details about the classification of diabetic retinopathy.
Treatment of Diabetic Retinopathy
Rationale for Treatment
A - Early referral to an ophthalmologist is particularly important for patients with type 2 diabetes and severe non-proliferative (pre-proliferative) retinopathy, since laser treatment at this stage is associated with 50% reduction in the risk of severe visual loss and vitrectomy (American Diabetes Association, 1998; Aiello et al., 1998; Ferris, 1996). (Grade A, Level Ia)
Treatment Strategies for Diabetic Retinopathy
A - The following table shows recommended treatments for various degrees of diabetic retinopathy (Early Treatment Diabetic Retinopathy Study Research Group [ETDRS], 1985; ETDRS "Treatment techniques," 1987; ETDRS "Techniques for scatter," 1987; ETDRS, 1991; ETDRS, 1995).
Table. Treatment Strategies
Degree of Retinopathy |
Treatment |
No macular edema |
None |
Macular edema threatening or involving macular centre |
Focal/grid macular laser |
NPDR Mild/Moderate
Severe/Very severe
|
None
Consider scatter laser*
|
PDR Non high-risk & High-risk Advanced
|
Scatter laser without delay
Scatter laser without delay+ |
NPDR - Non-proliferative diabetic retinopathy
PDR - Proliferative diabetic retinopathy
*Especially in older-onset patients (type 2)
+See Section 5.3 on vitreous surgery in the original guideline document
(Grade A, Level Ib)
Vitreous Surgery
GPP - It is advisable to refer cases requiring vitreous surgery to an ophthalmologist familiar with vitreoretinal surgery.
Sight-Threatening Diabetic Retinopathy with Cataract
GPP - In patients in whom the presence of cataract precludes adequate photocoagulation, cataract surgery followed by prompt laser treatment is recommended. However, laser treatment should be given before cataract surgery if fundal visibility permits.
Ophthalmic Follow-up of Diabetic Patients
C - The timing of the follow-up examination of patients with diabetic retinopathy is dependent on the status of the retinopathy.
Table. Ophthalmic Follow-up
Status of Retinopathy |
Follow-up (months) |
No retinopathy |
12 |
Mild/moderate NPDR without retinal edema |
6 to 12 |
Mild/moderate NPDR with retinal edema, but not threatening or involving macula |
4 to 6 |
Mild/moderate NPDR with CSME or threatening the macula (Treat with laser) |
1 to 4 |
Severe or very severe NPDR (Treat with laser) |
1 to 4 |
PDR (Treat with laser) |
1 to 4 |
Adapted from AAO summary Benchmarks, June 2001
NPDR - Non proliferative diabetic retinopathy
CSME - Clinically significant macular edema
PDR - Proliferative diabetic retinopathy
(Grade C, Level IV)
Definitions:
Levels of Evidence
Level Ia: Evidence obtained from meta-analysis of randomised controlled trials
Level Ib: Evidence obtained from at least one randomised controlled trial
Level IIa: Evidence obtained from at least one well-designed controlled study without randomisation
Level IIb: Evidence obtained from at least one other type of well-designed quasi-experimental study
Level III: Evidence obtained from well-designed non-experimental descriptive studies, such as comparative studies, correlation studies, and case studies
Level IV: Evidence obtained from expert committee reports or opinions and/or clinical experiences of respected authorities
Grades of Recommendation
Grade A (evidence levels Ia, Ib): Requires at least one randomised controlled trial as part of the body of literature of overall good quality and consistency addressing the specific recommendation
Grade B (evidence levels IIa, IIb, III): Requires availability of well conducted clinical studies but no randomised clinical trials on the topic of recommendation
Grade C (evidence level IV): Requires evidence obtained from expert committee reports or opinions and/or clinical experiences of respected authorities. Indicates absence of directly applicable clinical studies of good quality
GPP (good practice points): Recommended best practice based on the clinical experience of the guideline development group.