Abstract
Purpose:
To examine differences in ophthalmic artery (OA) and central retinal artery (CRA) blood flow velocities and vascular resistance between diabetic and non-diabetic patients with open angle glaucoma (OAG) after three years.
Methods:
82 patients (17 diabetic, 65 non-diabetic) with OAG were assessed at baseline and three years follow up for retrobulbar blood flow and vascular resistance (RI) using color Doppler imaging in the OA and CRA. Repeated measures analysis of covariance was used to compare the baseline and three year measurements. All measures had 95% confidence intervals with p<0.05 considered statistically significant.
Results:
Diabetic OAG patients had significantly increased OA RI and CRA RI compared to non-diabetic OAG patients (p<0.0126 and p<0.0063 respectively). Diabetic patients had higher OA RI and CRA RI [mean (95% CI)] at three years [x=0.808 (0.833, 0.779); x=0.731 (0.757, 0.702)] than at baseline [x=0.744 (0.773, 0.712); x=0.682 (0.716, 0.645)]. The differences between three-year values from baseline for OA RI and CRA RI were statistically significant [Δ=0.084, (0.135, 0.039), p<0.0001; Δ=0.057 (0.104, 0.016), p<0.0060]. Non-diabetic patients had higher OA RI and lower CRA RI at three years [x=0.774 (0.790, 0.757); x=0.710 (0.725, 0.695)] than at baseline [x=0.755 (0.769, 0.741); x=0.716 (0.731, 0.700)]. The difference between three-year values from baseline for OA RI was statistically significant [Δ=0.021, (0.041, 0.002), p<0.0312]. However, the difference between three-year values from baseline for CRA RI was not statistically significant [Δ=-0.005 (0.012, -0.022), p<0.5327]. Changes in OA and CRA peak systolic velocity and end diastolic velocity, from which RI was derived, after three years were not statistically significant (p>0.05).
Conclusions:
Diabetic patients with OAG had significantly increased OA and CRA vascular resistance compared to non-diabetic OAG patients after three years. Diabetes is known to have systemic vascular manifestations, which may be reflected in their glaucoma pathophysiology. Our data suggests that diabetic patients with OAG may have more ocular vascular contributions to the glaucoma disease process compared to non-diabetic OAG patients.
Keywords: 498 diabetes •
436 blood supply