Abstract
Purpose:
To assess differences in non-invasive cerebrospinal fluid (CSF) pressure, ocular hemodynamic parameters and to evaluate their correlation with neuroretinal rim area (NRA) in normal-tension glaucoma (NTG) and healthy controls.
Methods:
18 patients with NTG (age 56.2(10.2)) and 9 healthy controls (age 51.3(6.3)) were included in the prospective clinical trial. Non-invasive CSF pressure was measured using novel two-depth Orbital Doppler device (Vittamed 205, Kaunas, Lithuania), technology based on simultaneous blood flow signals in intracranial and extracranial segments of the ophthalmic artery (OA). Retrobulbar blood flow was measured using Color Doppler imaging (CDI, Accuvix, Seoul, Korea) in the OA and central retinal (CRA) arteries, assessing peak-systolic (PSV) and end-diastolic (EDV) velocities, and calculated resistance index (RI). Confocal laser scanning tomography (HRT, Heidelberg, Germany) was used to measure NRA. The level of significance p<0.05 was considered significant.
Results:
CSF pressure was statistically significantly lower in NTG (8.08(2.64) mmHg), compared with healthy controls (10.8(2.60) mmHg), p=0.02. Patients with NTG also had decreased CRA EDV (3.57(0.86) cm/s) and increased CRA RI (0.64(0.07)), compared with healthy subjects (respectively, 4.79(1.18) cm/s and 0.58(0.06)), p<0.05. Lower CSF pressure was associated with decreased NRA (c=0.67, p=0.002) in NTG group. Lower ocular perfusion pressure was related to decreased CRA EDV (c=0.52, p=0.02) in NTG. Higher CRA RI was correlated with decreased NRA (c=-0.63, p=0.005) in healthy controls.
Conclusions:
Normal-tension glaucoma patients had lower CSF pressure which correlated with decreased neuroretinal rim area. Additionally, lower ocular perfusion pressure was related with decreased CRA EDV. CSF pressure seems to be of major importance in normal-tension glaucoma and future investigations are needed to elucidate the involvement of CSF pressure in glaucoma management.
Keywords: 568 intraocular pressure •
627 optic disc