Abstract
Purpose: :
To evaluate ocular haemodynamics in patients with non-arteriitic anterior ischaemic optic neuropathy (NAION) by colour Doppler imaging and to correlate blood flow parameters to visual field loss.
Methods: :
Blood flow velocities (peak systolic velocity (PSV) and end-diastolic velocity (EDV)) of the ophthalmic artery, central retinal artery (CRA) and posterior ciliary arteries (PCA) were measured using colour Doppler imaging (Siemens Sonoline Sienna). Retinal arteriovenous passage times (AVP) were evaluated using fluorescein angiography (scanning laser ophthalmoscope) and digital image analysis. The visual field global index mean deviation (MD) of the Humphrey visual field 30-2 was used for statistical analysis.
Results: :
Twenty consecutive patients with acute NAION were included (age 64 years ±11, 13 male, 7 female, mean duration of symptoms 7.6 ±7 days). Initial mean defect was -15.4 ±8.9 dB, AVP was determined with 1.66 ±0.37 and EDV with 2.01 ±0.60 cm/s. EDV of the CRA was significantly correlated to AVP (r=-0.49, p=0.025). MD was significantly correlated to EDV of the CRA (r=0.52, p=0.017). No significant correlation was found for MD and AVP (r=0.09, p=0.70). Furthermore no correlations were detected for MD to PSV and EDV of OA and short PCA.
Conclusions: :
Decreased end-diastolic blood flow velocities of the CRA seem to be linked to the visual field damage in NAION. An improvement of the retrobulbar circulation might be beneficial in the treatment of NAION.
Keywords: neuro-ophthalmology: optic nerve