Color Doppler imaging and glaucoma: comparison of Doppler Waveform and velocities of retrobulbar vessels between a glaucomatous patient and a healthy subject

Purpose To compare the colour Doppler imaging (CDI) waveform and velocities of the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCA) of a patient with normal tension glaucoma (NTG) compared to a healthy subject. Methods The right eye of two subjects (a patient with NTG and a healthy subject) were investigated. The same examiner performed CDI examination of the OA, CRA and SPCA using the CDI device ESAOTE MYLAB™ (probe LA533 13-6 MHz small parts-vascular linear array). The peak systolic velocity (PSV), the end-diastolic velocity (EDV), the resulting resistivity index (RI) were evaluated. Two aspects of the Doppler waveform were considered: the Early Systolic Acceleration (the slope of the fastest moving portion of the systolic component, ESA) and the ratio between the mean velocities of the systolic and diastolic components (Sm/Dm). Results All the measured velocities, except for the PSV in the ophthalmic artery, are reduced and the RIs are increased in the glaucomatous patient compared to the healty subject. Moreover, ESA is reduced and Sm/Dm increased if compared to the healthy volunteer. Conclusion The values obtained are in agreement with the literature. Further studies are needed to evaluate the degree of the pathological alterations and their role in the progression of the optic nerve injury.