An evaluation using colored doppler ultrasonography of central retinal artery hemodynamics in the healthy eye in individuals with late monocular blindness
Abstract
Structural and functional changes occur in the brain after vision losses. The purpose of the present study was to investigate central retinal artery (CRA) hemodynamics in the healthy eye of individuals developing late monocular blindness (LMB) using colored Doppler ultrasonography. The CRAs of 13 healthy eyes of 13 patients with LMB and of 13 healthy individuals as a control group were evaluated in this prospective study. Peak systolic velocity, end-diastolic velocity, mean flow velocity, systolic/diastolic velocity ratio, and resistivity and pulsatility index (RI, PI) values in the CRAs were determined using colored Doppler ultrasonography in both groups. The mean age of all the individuals examined was 39.3 +/- 12.3 years, and loss of vision in the LMB patients had been present for a mean 22 +/- 13.2 years. The PSH, DHS, and mean flow velocity values in the LMB group were 13.3 +/- 2.5 cm/s, 3.1 +/- 0.8 cm/s, and 6.5 +/- 1.6 cm/s, respectively, significantly lower than in the control group at 18.6 +/- 5 cm/s, 5.5 +/- 2.8 cm/s, and 10 +/- 3.2 cm/s (P< 0.05). The PI, RI, and systolic/diastolic velocity ratio values differences in the both group were not statistically significant (P> 0.05). In conclusion, the absence of a significant difference in RI and PI values between the 2 groups revealed that vascular resistance did not develop in the CRA hemodynamics of healthy eyes of individuals with LMB, although the low velocity values showed an increase in CRA width.