Pulsatile ocular blood flow among normal subjects and patients with high tension glaucoma.

PURPOSE

To estimate pulsatile ocular blood flow (POBF) among normal subjects and to compare various parameters in eyes of primary open angle glaucoma with high intraocular pressure (IOP).

METHODS

POBF was estimated in 95 eyes of 95 normal subjects above the age of 40 years and in 35 eyes of 35 primary open angle glaucoma patients using the OBF system (OBF Labs Ltd., UK). Correlation of age, gender, IOP, pulse amplitude, pulse volume and pulse rate with POBF was studied. POBF values were measured in glaucomatous patients before IOP control and one month later after control of IOP to < 22 mmHg.

RESULTS

The mean POBF among normal subjects was 1382.2 +/- 413 ml/min (range 636-2291 m/min). Females had a significantly higher mean POBF (1512 +/- 347 ml/min) than males (1193 +/- 312 ml/min). The mean IOP among normal subjects was 12.6 mmHg and in glaucoma patients, 29.1 mmHg. Mean POBF in glaucomatous eyes with initially elevated IOP was 718.9 +/- 322.6 ml/min, which improved after IOP control to 1129 +/- 291 ml/min. IOP had a strong (P < .01) negative correlation with POBF (r = -0.667)

CONCLUSIONS

POBF among eyes of normal subjects in this study is higher than reported among Caucasian eyes. Primary open angle glaucoma eyes with high IOP have significantly reduced ocular blood flow. Therapy aimed at lowering IOP has a positive effect onocular haemodynamics.