Diagnosis and Ancillary Testing

DIAGNOSIS AND ANCILLARY TESTING
Psychophysical abnormalities are commonly found in diabetic patients and they manifest as poor night vision (dark adaptation) and poor recovery from bright lights (photo stress) [67]. Color vision also suffers alterations in patients with diabetes ,blue-yellow discrimination being affected earlier than red-green discrimination. Clinical examination should include best corrected visual acuity, slit-lamp examination to detect iris neovascularization, intraocular pressure because of the increased risk of glaucoma, gonioscopy to rule out angle neovascularization and fundus examination following pupillary dilatation to assess the severity of DR. A number of tests ancillary to the clinical examination may enhance patient care, the most common including color fundus photography, fluorescein angiography, ultrasonography and optical coherence tomography.
Color fundus photography
Being a more reproducible technique, color fundus photography is frequently used in clinical research studies. It may be useful for documenting significant progression of disease and response to treatment, but it is rarely valuable in cases of minimal DR. Also, for detecting retinal thickening associated with macular edema and fine caliber NVD or NVE, clinical examination appears to be superior.

Fluorescein angiography
In selected patients with DR, fluorescein angiography is most helpful to assess the severity of DR, to determine sites of leakage in macular edema, to judge the extent of capillary nonperfusion and to confirm neovascularization [40]. Still, we must be aware of the potential risks associated with the procedure because severe medical complications may occur, including death [68].
Ultrasonography
In diabetic eyes with op...

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...l[85]. The patients received either intensified or standard treatment with hypogycemic agents, targeting a HbA1c of 6% respectiv 7.0–7.9%. The trial analysed a subgroup of 2856 patients concerning the relation between glycemic control and incidence and progression of retinopathy and the results showed that glycemic control reduce with 33% the risk of progression.
There are some metaanalysis showing that effect of metabolic control on retinopathy is overestimated and there are not sufficient data to sustain that a relative risk reduction will apear after improving HbA1c [86]. Disglycemia can be involved in progression of retinopathy as hypoglycemia is also underestimated. In the group with intensive treatment a 30% increase of severe hypoglycemia was noted compared with standard group, but still are not enough data to blame hypoglycemia for progressing retinopathy.