Colour Doppler imaging of retrobulbar circulation in different severity of glaucoma optic neuropathy

Abstract

Aims: To compare retrobulbar hemodynamic measured by colour Doppler imaging (CDI) in patients with a different severity of glaucoma and to correlate variables CDI with the structural parameters of the retina and optic disc.Material and methods: Of 89 eyes studied, 31 had preperimetric, 29 early, 12 moderate and 17 advanced glaucoma. Peak systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI) in ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCAs) were evaluated by CDI and compared between study groups. Retinal nerve fibre layer thickness (RNFL) and optic disc parameters measured with optical coherent tomography (OCT) were correlated with the Doppler variables.Results. In eyes with advanced, moderate and early glaucoma EDV SPCAs were significantly lower as well as RI SPCAs were significantly higher compared to the eyes with preperimetric glaucoma. In eyes with advanced and moderate glaucoma RI CRA (0.74 and 0.71) were significantly higher than in eyes with preperimetric glaucoma (0.68) (p=0.014 and 0.026). In eyes with advanced glaucoma PSV OA and PSV CRA were significantly lower than in eyes with preperimetric glaucoma (32.5 vs. 40.7 cm/s p=0.034 and 8.25 vs. 9.7 cm/s p=0.022, respectively). Positive, variable correlations were found between RNFL and EDV of all measured arteries (0.21<R<0.50, p<0,05).Conclusions: Statistically significant alterations in the Doppler parameters of retrobulbar arteries in association with thinning of the RNFL were observed in patients with glaucoma along with a greater severity of optic neuropathy.