Diffusion restriction of the optic nerve in patients with acute visual deficit.
OBJECTIVE
Diffusion magnetic resonance imaging (MRI) is commonly used in acute stroke, but not considered diagnostic in ischemic optic neuropathy. This study evaluates the presence of diffusion restriction in patients with acute visual loss by analyzing diffusion-weighted images (DWI).


METHODS
A retrospective study of all patients who clinically presented with acute visual loss and who underwent MRI with DWI between January 2011 and May 2012 were evaluated. Patients with suspected brainstem ischemia were used as a control group. Two neuroradiologists evaluated the DWI for the presence of diffusion restriction within the optic nerve.


RESULTS
In all, 34 patients with acute visual deficit and 32 controls were evaluated. In all five cases of acute optic ischemia, diffusion restriction with reduced apparent diffusion coefficient was present. In 2/25 patients with clinically defined optic neuritis, a diffusion restriction was present. No diffusion restriction was seen in the control cases or in cases with other causes for an acute visual deficit.


CONCLUSIONS
DWI can identify ischemic lesions of the optic nerve. As in acute multiple sclerosis lesions, optic neuritis can also present in rare circumstances with diffusion restriction and can therefore not be ruled out solely by DWI MRI.
Department of Diagnostic and Interventional Neuroradiology, University Hospital, Tübingen, Germany.
Benjamin
B
Bender
Christian
C
Heine
Sören
S
Danz
Felix
F
Bischof
Katrin
K
Reimann
Miriam
M
Bender
Thomas
T
Nägele
Ulrike
U
Ernemann
Andreas
A
Korn
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004058:Diffusion; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009900:Optic Nerve / Q000473:pathology*; D018917:Optic Neuropathy, Ischemic / Q000150:complications / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014786:Vision Disorders / Q000209:etiology / Q000473:pathology*; D066127:White Matter / Q000473:pathology*
DWI; MRI; optic ischemia; optic nerve; optic neuritis