Evaluation of acute anterior ischaemic optic neuropathy using diffusion tensor imaging

Adequate diagnosis of acute anterior ischaemic optic neuropathy (AION) is challenging to achieve with traditional medical imaging approaches. The aim of this study was to evaluate the detection capacity of diffusion tensor imaging for abnormalities of the optic nerve in acute AION patients.

Diffusion tensor imaging data were collected from 31 patients with acute AION and 20 healthy subjects. The mean fractional anisotropy and apparent diffusion co-efficient subsequently were evaluated across all subjects.

In affected nerves, the mean fractional anisotropy was reduced and the mean apparent diffusion co-efficient was increased in acute AION patients compared with control nerves (p < 0.001), as well as clinically unaffected contralateral nerves (p < 0.001). The mean fractional anisotropy and apparent diffusion co-efficient demonstrated no difference between normal control nerves and clinically unaffected contralateral nerves (p = 0.73 and 0.92, respectively).

Diffusion tensor imaging of the optic nerves demonstrated diagnostic potential for acute AION and could serve as a novel tool for the detection and evaluation of therapies.