Abstract
Purpose: :
To investigate the effect of intravitreal anti-VEGF treatment on the vascular microstructure of the foveal avascular zone in patients with macular disease secondary to diabetic macular edema (DME) or branch retinal vascular occlusion (BRVO).
Methods: :
In 62 patients the area (in square millimeters) of the foveal avascular zone was manually assessed by measuring the capillary circumference in an early phase fluorescein angiogram picture (SLO, Heidelberg Retina Angiograph II) The area was measured preoperatively and after any injection given within the observation period of 9 months. Primary end point of this retrospective clinical study was the change in area size of the foveal avascular zone during intravitreal anti-VEGF treatment.
Results: :
We found that the area of the foveal avascular zone increased significantly with any injection of anti-VEGF in patients with macular disease secondary to DME or BRVO. Preoperatively parameters showed a mean area of 0.325 ± 0.123 square millimeters (median 0.305). After 9 months the mean area was assessed at 0.489 ± 0.147 square millimeters (median 0.485). With each injection the area increased significantly by 0.061 square millimeters (p<0.001).
Conclusions: :
Intravitreal injection of anti-VEGF agents seems to alter the vascular structure of the foveal avascular zone. It was found that with each injection the area of the FAZ increased significantly. Impairment of macular micro-perfusion and capillary network needs to be considered with the application of anti-VEGF agents during treatment of macular disease in patients with DME or BRVO.
Keywords: macula/fovea • shape and contour • injection