Abstract
Purpose :
To evaluate the perfusion status of the retina and the choriod at the area of laser effects in diabetic patients using swept-source optical coherence tomography angiography (OCTA) widefield images.
Methods :
Cross-sectional exploratory analyses of OCTA-images recorded at the subspecialty unit of diabetic retinopathy at the Department of Ophthalmology, Medical University Vienna. 12x12mm OCTA images recorded with the Zeiss Plex Elite 9000, (Carl Zeiss Meditec, Jena) were reviewed for laser effects. The over-/underlying capillary networks were graded at the area of each laser spot following a three-step grading system (normal – sparse – missing capillary network). The superficial and deep capillary plexus of the retina and the choriocapillaris were graded separately.
Results :
A total of 1452 laser effects in 48 eyes of 24 patients (12 female, mean age 59 ± 12 yrs) were included in this analyses. In the retina, the superficial and deep capillary network appeared normal in 38% and 34%, sparse in 26% and 28%, and was missing in 36% and 38% at the area evaluated. Capillary dropout in the retina was not restricted to the area of prior laser treatment. The choriocapillaris was either sparse (22%) or completely missing (78%) at the circumscribed area of laser spot. In the area adjacent to the laser effects the perfusion of the choriocapillaris appeared normal.
Conclusions :
OCTA imaging allows the assessment of the perfusion status of each capillary plexus separately even in areas previously treated with laser. Capillary non-perfusion in the choriocapillaris was found in the circumscribed area of laser treatment. Laser coagulation does not only seem to destroy the photoreceptors and the retinal pigment epithelium, but also causes a sustained non-perfusion of choriocapillaries at the area treated.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.