Abstract
Purpose: :
Ocular pulse amplitude (OPA) reflects the modulation of the intraocular pressure (IOP) due to the cardiac cycle. OPA is the difference between the systolic and diastolic IOP. This study was performed to correlate OPA and flow velocities of the retrobulbar vessels.
Methods: :
48 glaucoma patients (age 62 ± 16; 24f, 22m) were included in a prospective study. OPA was determined by dynamic contour tonometry (DCT) measuring IOP values at high frequency. Color Doppler imaging (Siemens Sonoline Sienna) was used to assess peak systolic (PSV) and end–diastolic velocities (EDV) in the ophthalmic artery (OA), the central retinal artery (CRA), the central retinal vein (CRV), the temporal (TPCA) and the nasal short ciliary arteries (NPCA). Furthermore, systemic blood pressure values and the heart frequency rate were determined.
Results: :
Mean OPA was 3.0 ± 1.7 mmHg. Mean PSV in the TPCA (7.1± 1.1 cm/s; r = 0.57; p < 0.0001) and in the NPCA (6.9± 1.1cm/s; r= 0.45; p<0.0016) were significantly correlated to the OPA. No correlation was found for OPA and flow velocities in OA and in CRA. Furthermore, there was no correlation between OPA and cardiovascular parameters and IOP.
Conclusions: :
In this study we found a correlation between ocular pulse amplitude and flow velocities of the short posterior ciliary arteries. Future studies are needed to prove the diagnostic relevance of assessment of OPA.
Keywords: optic flow • intraocular pressure • blood supply