Hemodynamic study on normal tension glaucoma with color Doppler ultrasound

Objective To investigate the blood supply of optic nerve in normal tension glaucoma (NTG).Methods For both groups of NTG and normal eyes, color Doppler flow image (CDFI) was used to observe the peak systolic velocity (PSV), end diastolic velocity (EDV), and resistivity index (RI) of ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary artery (SPCA), respectively. Results Comparing to the normal group, the PSV, EDV of OA,CRA and SPCA of the NTG group were slower and the differences were statistically significant (t = 2.83,4.57, 2.94,3.17, 6.69, 5.22, P 0.05). The RI of OA, CRA, and SPCA increased in the NTG group which had statistical difference compared with the normal group (t=2.75,2.94,2.89,P 0.05). Conclusions The optic nerve in normal tension glaucoma lacks blood supply. CDFI has high value in normal tension glaucoma's early diagnosis.