Clinical interpretation of retinal circulatory measurements. IV. Photocoagulation in diabetic retinopathy and venous occlusive diseases
Ophthalmologica, 193 (1-2):
108--125 (1986)Abstract
Based on the pathomechanism of diabetic retinopathy, the effect of
photocoagulation on retinal microcirculation as assessed by measurements of
retinal microcirculation magnitudes is discussed. The clinico-experimental
results support the opinion that an essential effect of photocoagulation is due
to an improvement in the flow conditions of the noncoagulated central retinal
area with regard to metabolic exchange and stasis situation by the
coagulation-induced occlusion of peripheral capillary areas. Further
clinico-experimental measurements of retinal microcirculation magnitudes for the
assessment of the behavior of microcirculation after photocoagulation in venous
occlusive diseases of the retina are presented. It is shown that retinal
microcirculation immediately after photocoagulation reacts by transitory
instationary flow conditions; in this period it is quite possible that an
additional blood flow reduction over several days will occur. In particular, the
effect of photocoagulation in venous occlusive diseases with narrow arterial
vessels is discussed. It is emphasized that with regard to the therapeutic effect
of photocoagulation as well as to the discussion of pathomechanisms, apart from
blood flow, the differentiated behavior of single retinal vascular areas, such as
arteries, arterioles, capillaries, venules and veins, requires more attention.
Particularly with this in mind, substantial improvements in differential
diagnosis and treatment of retinal circulatory disturbances may be expected from
measurements of retinal circulation magnitudes.