Visualization of retinal and choroidal blood flow with fluorescein leukocyte angiography in rabbits.

PURPOSE

To visualize the retinal and choroidal leukocytes in rabbits with a new technique, fluorescein leukocyte angiography using a scanning laser ophthalmoscope.

METHODS

Blood was withdrawn from an ear vein of a rabbit (New Zealand White), mixed with fluorescein dye in a test tube and centrifuged. The yellow-brown coat layer containing fluorescein-stained leukocytes was collected and injected into the ear vein of the same rabbit while performing fluorescein angiography with a scanning laser ophthalmoscope. The angiographic image displaying circulating fluorescent leukocytes in retinal and choroidal vessels was recorded on a videotape.

RESULTS

Fluorescent leukocytes were clearly visible in the retinal arteries, capillaries, veins and choroidal vessels for more than 1 h. Plugging of leukocytes was seen throughout this period of time in choroidal vessels, while plugging was rare in retinal vessels.

CONCLUSIONS

Fluorescein leukocyte angiography is a new technique which can be used for visualization of the leukocytes in retinal and choroidal vessels non-invasively and in vivo.