Abstract
Abstract: :
Purpose: Choroidal perfusion abnormalities may play an important role in the pathogenesis of AMD. We analyzed the association between choroidal vascular hemodynamics and systemic blood pressure in patients with AMD. Methods: The study population consisted of 31 subjects enrolled at Scheie Eye Institute in the Complications of Age-Related Macular Degeneration Prevention Trial. All patients had ten or more large drusen in each eye. Fluorescein angiograms were obtained and relative foveolar choroidal blood velocity (ChVel), volume (ChVol), and flow (ChFlow) were measured using laser Doppler flowmetry (LDF, Oculix). Upon completion of LDF measurements, brachial artery systolic (BPs) and diastolic blood pressure (BPd) were measured by sphygmomanometry and intraocular pressure (IOP) was determined by Goldmann applanation tonometry. Fluorescein angiograms were analyzed in a masked fashion for evidence of patchy choroidal filling, defined as one or more MPS disc areas of prolonged, patchy choroidal hypofluorescence present in the early phases of the angiogram. Results: The age of the patients ranged from 58 to 85 years, 74±8 (mean ± standard deviation). The mean blood pressure ranged from 82 to 114 mmHg with an average of 98 ± 10 mmHg; the BPs ranged from 125 to 166 mmHg, 140 ± 16 mmHg; the average BPd was 77±8 mmHg, ranging from 64 to 88 mmHg. Nine of the 31 fluorescein angiograms showed evidence of patchy choroidal filling. There was a significant positive correlation between the time until complete filling of the choroid (ChorFILL) and mean blood pressure (R=+0.81;p=0.008), diastolic blood pressure (R=+0.83; p=0.006), and systolic blood pressure (R=+0.75; p=0.019. Patients with higher blood pressure tended to have more prolonged ChorFILL. There was no significant correlation between ChFILL and ChVel (R=+0.18; p=0.64), ChVol (R=-0.40; p=0.28), or ChFlow (R=-0.48; p=0.20). Conclusions: Our results show that increased systemic blood pressure is associated with prolonged choroidal filling time in AMD patients. Systemic hypertension is a risk factor for the development of AMD and its effect on the development of AMD may be mediated by choroidal circulatory abnormalities. Acknowledgements: Supported by NIH grants EY 12769 and EY 12279, the Vivian S. Lasko Research Fund and Research to Prevent Blindness.
Keywords: 308 age-related macular degeneration • 345 choroid • 331 blood supply