Color Doppler imaging of the retrobulbar circulation in nonexudative and exudative age-related macular degeneration

Introduction
To study ocular perfusion in the ophthalmic artery, central retinal artery, nasal and temporal posterior ciliary arteries in nonexudative and exudative age-related macular degeneration.

Material and methods
Twenty five subjects with nonexudative age-related macular degeneration were compared to twenty five subjects with exudative age-related macular degeneration and to twenty five age-matched control subjects. Color Doppler imaging measured peak systolic velocity (PSV) and end diastolic velocity (EDV) in the ophthalmic artery, central retinal artery, nasal and temporal posterior ciliary arteries of one eye. The resistivity index (RI) and the pulsatility index (PI) were calculated.

Results
There were statistically significant differences between: subjects with nonexudative age-related macular degeneration and subjects with exudative age-related macular degeneration in EDV, RI and PI in the ophthalmic artery and PSV in the temporal posterior ciliary artery, subjects with nonexudative age-related macular degeneration and control subjects in RI in central retinal artery, subjects with nonexudative age-related macular degeneration and control subjects in RI and PI in nasal posterior ciliary artery, subjects with exudative age-related macular degeneration and control subjects in PI in nasal posterior ciliary artery.

Conclusions
The study results showed reduced ocular blood flow in patients with nonexudative age-related macular degeneration compared to patients with exudative age-related macular degeneration and to control subjects. The higher RI in central retinal artery in nonexudative age-related macular degeneration compared to control subjects, suggest there may be a more generalized perfusion abnormality beyond the choroid.