REVIEW
SA JOURNAL OF DIABETES & VASCULAR DISEASE
96
VOLUME 7 NUMBER 3 • SEPTEMBER 2010
worldwide and the type of programme utilised will depend largely
on the availability of personnel (trained ophthalmic nurses, general
practitioners, endocrinologists, optometrists, technicians doing
fundus photography).
Single-field fundus photography is not a substitute for a
comprehensive ophthalmic examination, but there is level I evidence
that it can serve as a screening tool for diabetic retinopathy to identify
patients with retinopathy for referral for ophthalmic evaluation and
management. The advantages of single-field fundus photography
interpreted by trained readers are: ease of use (only one photograph
is required), convenience, and ability to detect retinopathy.
13
Having
said that, this technology is not considered a replacement for a
comprehensive eye evaluation by an ophthalmologist, but in a
resource-poor area, it can be of considerable assistance in sifting
through a large number of patients to prioritise referrals to the
ophthalmologist.
Ancillary tests
Apart from colour fundus photography, other useful ancillary tests
sometimes ordered by the ophthalmologist include:
• optical coherence tomography (OCT). This is a new imaging
technique using near-infrared frequency light to obtain an
almost living histological picture of the retina, showing the
vitreo-retinal interface, retina and sub-retinal space. It is
extremely useful for exactly quantifying retinal thickness and
diagnosing vitreo-macular traction, which is amenable to
surgery (Figures 4 and 5).
• fundus fluorescein angiography (FFA). This entails the
intravenous administration of fluorescein dye, followed by
fundus photography through a special filter to identify areas
of capillary non-perfusion, new vessels or sources of capillary
leakage resulting in macular oedema (Figures 6–9).
Management
Laser (photocoagulation) ‘surgery’ is still the gold-standard
treatment for diabetic retinopathy. In general, it is advised for
patients with high-risk PDR, CSME or neovascularisation of the
anterior chamber angle (Table 4). Vitrectomy is also an important
part of the treatment strategies for advanced diabetic retinopathy
and has been shown to increase vision-related quality of life.
14
Newer but generally temporary therapies include intra-vitreal
injections of steroids (triamcinolone acetonide) or anti-VEGF
Figure 4.
OCT showing cystoid macular oedema.
Figure 5.
OCT showing vitreo-macular traction
Figure 6.
FFA showing capillary non-perfusion and leakage.
Capillary non-
perfusion
Leakage from
NVE
Figure 7.
FFA showing leakage from new vessels elsewhere.
Leakage
from NVE
Micro-
aneurysms
