PURPOSE: To assess a novel magnetic resonance imaging (MRI) protocol for quantifying the optic nerve diameter (OND) as a measure of axonal loss in the optic nerve. METHODS: Included in the study was one eye each from 47 subjects, of whom 9 had no eye disease, 16 had preperimetric glaucoma, 11 had a glaucomatous mean visual field defect of <10 dB and 11 of >10 dB. Each subject underwent automated perimetry, scanning laser polarimetry, optic coherence tomography, scanning laser tomography, and ultrafast high-resolution MRI at 3 T. OND was determined 5, 10, and 15 mm behind the eye with a half Fourier-acquired single-shot turbo spin-echo (HASTE)-sequence requiring 1.5 seconds of data acquisition time per slice and providing a spatial resolution of 0.11 mm. A multiple linear regression model was applied to determine correlations (r) among the different techniques. RESULTS: The correlation (r) was <0.37 for OND measurements taken 5 mm behind the eye. At 10 mm behind the eye, r increased to 0.57 and was statistically significant in four out six instances. In the orbital apex 15 mm behind the eye, r reached a maximum of 0.80 and was statistically significant in all instances. OND correlated best with the retinal nerve fiber layer thickness measured by optic coherence tomography. CONCLUSIONS: Retina- or optic nerve head-related surrogate markers for axonal content correlated closely with the OND, although only when it was measured in the orbital apex. High-resolution MRI using an ultrafast HASTE-sequence at 3 T proved useful for OND quantification and may be a valuable asset in future neuroprotection trials.
PURPOSE: To assess a novel magnetic resonance imaging (MRI) protocol for quantifying the optic nerve diameter (OND) as a measure of axonal loss in the optic nerve. METHODS: Included in the study was one eye each from 47 subjects, of whom 9 had no eye disease, 16 had preperimetric glaucoma, 11 had a glaucomatous mean visual field defect of <10 dB and 11 of >10 dB. Each subject underwent automated perimetry, scanning laser polarimetry, optic coherence tomography, scanning laser tomography, and ultrafast high-resolution MRI at 3 T. OND was determined 5, 10, and 15 mm behind the eye with a half Fourier-acquired single-shot turbo spin-echo (HASTE)-sequence requiring 1.5 seconds of data acquisition time per slice and providing a spatial resolution of 0.11 mm. A multiple linear regression model was applied to determine correlations (r) among the different techniques. RESULTS: The correlation (r) was <0.37 for OND measurements taken 5 mm behind the eye. At 10 mm behind the eye, r increased to 0.57 and was statistically significant in four out six instances. In the orbital apex 15 mm behind the eye, r reached a maximum of 0.80 and was statistically significant in all instances. OND correlated best with the retinal nerve fiber layer thickness measured by optic coherence tomography. CONCLUSIONS: Retina- or optic nerve head-related surrogate markers for axonal content correlated closely with the OND, although only when it was measured in the orbital apex. High-resolution MRI using an ultrafast HASTE-sequence at 3 T proved useful for OND quantification and may be a valuable asset in future neuroprotection trials.
Authors: Robert O Duncan; Pamela A Sample; Christopher Bowd; Robert N Weinreb; Linda M Zangwill Journal: Vision Res Date: 2012-03-29 Impact factor: 1.886
Authors: Robert L Harrigan; Alex K Smith; Bailey Lyttle; Bailey Box; Bennett A Landman; Francesca Bagnato; Siddharama Pawate; Seth A Smith Journal: Mult Scler J Exp Transl Clin Date: 2017-09-13
Authors: Gala Beykin; Anthony M Norcia; Vivek J Srinivasan; Alfredo Dubra; Jeffrey L Goldberg Journal: Prog Retin Eye Res Date: 2020-07-10 Impact factor: 21.198