Color Doppler imaging of ophthalmic artery blood flow velocity: a study of repeatability and agreement.

PURPOSE: Color Doppler imaging (CDI) is a relatively new technique that allows quantification of blood flow velocity in orbital and ocular vasculature. Despite the numerous clinical studies that have used CDI, repeatability of this technique and agreement between observers have not been documented. METHODS: The authors performed a prospective investigation of the repeatability and agreement between observers on ophthalmic artery blood flow velocity measurements in 35 patients (35 eyes). RESULTS: Results on the estimated error of measurement (variability between repeated readings on the same subject) indicate good repeatability of the measurements; in fact, the measurement variances were only 5.6% for the peak systolic velocity, 11.4% for the end diastolic velocity, and 6.2% for the mean envelope velocity. The statistical analysis of repeatability showed a very narrow 95% confidence interval for both observers. The measurement of agreement between the two observers demonstrated the existence of a good concordance of the measurements taken by each observer on each subject. CONCLUSIONS: Results suggest that CDI is a reliable tool for quantitative assessment of ophthalmic artery blood flow velocity.

Ocular hypotensive effect of sublingual administration of timolol.

PURPOSE: A randomized clinical, trial to assess ocular hypotensive effect of sublingual administration of timolol was performed. PATIENTS AND METHODS: Seventeen (9 male, 8 female; age range 45 to 68 years) with bilateral ocular hypertension were selected for the study. Each patient was evaluated with regard to IOP, arterial blood pressure and heart rate before and after each of the following experimental treatment: unilateral ocular administration of 20 microliters of 0.5% timolol solution; sublingual administration of 20 microliters of 0.5% timolol solution; unilateral ocular administration of 20 microliters of saline solution (placebo); sublingual administration of 20 microliters of saline solution (placebo). The sequence of the treatments and the eye topically treated were randomly chosen. At least four weeks wash-out elapsed between each experimental treatment. RESULTS: Our results showed that sublingual administration of timolol was able to induce a bilateral significant reduction of the IOP. This reduction was not statistically different from that obtained in the eye treated with timolol. A significantly greater reduction of the IOP was obtained by sublingual timolol than in the contralateral eye after unilateral topical administration of timolol solution. No significant modification of arterial blood pressure and heart rate were evidenced after the treatment. CONCLUSIONS: Sublingual administration seems to be a new interesting way for reducing the IOP. Long term studies are required in order to test efficacy and safety of this new treatment.