Abstract
Purpose :
Application of tailored MRI sequences should improve diagnostic accuracy in acute optic neuritis (ON) and chronic optic neuropathy. This retrospective, observational study compares short tau inversion recovery (STIR) and 3D-fluid attenuation inversion recovery (FLAIR) in acute and chronic ON and correlates radiographic metrics to vision function and optical coherence tomography (OCT) structure.
Methods :
Orbital MRIs of 57 patients (56% female; mean age 50.8±16.7 years) with acute ON (n=15), chronic ON (n=31), or clinically normal (n=11) were retrospectively analyzed by masked neuroradiologists (2) and neuro-ophthalmologist (1) for presence of lesion, lesion signal normalized to normal frontal white matter, and lesion length. Clinical data included visual acuity (VA), OCT retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness, and automated perimetry mean deviation (MD) at presentation and outcome.
Results :
The diagnostic accuracy per reader for acute and chronic ON were 73-100% and 58-71%, respectively, for STIR and 87-100% and 48-71%, respectively for 3D-FLAIR. Diagnostic accuracy for chronic ON was lower than acute ON for one reader on STIR and both readers on 3D-FLAIR (p=0.02). Average ROI of acute and chronic ON lesions were higher than clinically normal cases on STIR (p=0.01 and p<0.01, respectively) and 3D-FLAIR (p=0.07 and p=0.08, respectively). Presenting LogMar VA for acute ON correlated with mean lesion length (r=0.55) and ROI (r=0.54) on STIR (p<0.05). The mean lesion length on STIR correlated to presenting (r=-0.67) and final (r=-0.92) GCL in acute ON (p<0.01) and to RNFL (r=-0.44) and GCL (r=-0.48) in chronic ON cases (p<0.05). In acute ON, the mean lesion length on FLAIR correlated with the presenting GCL (r=-0.69, p<0.01); and the outcome GCL with the mean lesion ROI on STIR (r=-0.67, p<0.05). No MRI features correlated with final VA or MD for acute or chronic ON.
Conclusions :
3D-FLAIR and STIR have similar detection rates for ON lesions, but FLAIR had slightly greater sensitivity for acute ON. Use of a normalized quantitative ROI increased diagnostic accuracy for detecting abnormal signal. In acute ON, longer lesions and increased signal on STIR corresponded to worse presenting VA and greater structural loss reflected by OCT GCL and RNFL thinning, suggesting MRI might help predict outcome neuronal loss in acute ON.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.