Michael J Hoch1, Mary T Bruno, Timothy M Shepherd. 1. Department of Radiology and Imaging Sciences (MJH), Emory University, Atlanta, Georgia; Department of Radiology, Section of Neuroradiology (MTB, TMS), New York University Langone Medical Center, New York, New York; and Center for Advanced Imaging Innovation and Research (CAI2R) (TMS), New York, New York.
Abstract
BACKGROUND: Clinical orbital MRI protocols are routinely used to study the optic nerves and exclude compressive lesions, infarctions, or inflammation. However, the small caliber and divergent oblique orientations of the optic nerves make it challenging to characterize them well with conventional MRI, especially since adjacent air-filled bony structures distort the MRI signal and motion is a problem even in cooperative, healthy volunteers. EVIDENCE ACQUISITION: Over the past 3 years we have experimented with multiple novel MRI approaches and sequences to better characterize the optic nerves. The perfect MRI protocol would be quantitative and sensitive to subtle optic nerve pathologic changes, provide high spatial resolution, be rapidly acquired, and resistant to motion degradation. RESULTS: This review provides an update of recent MRI sequence innovations for the optic nerves being currently translated into clinical practice. Methods discussed include rapid MRI with compressed sensing or simultaneous multislice approaches, postprocessing techniques for quantitative T2 mapping or track density imaging, and multiple MRI sequences for measuring diffusion in the optic nerves. CONCLUSIONS: Recently-developed orbit-specific MRI coils, quantitative sequences, and rapid acquisition techniques can improve our future ability to study optic nerve pathologies noninvasively. As advanced MRI becomes more proficient at characterizing the optic nerves, its role in the clinical management of patients should increase.
BACKGROUND: Clinical orbital MRI protocols are routinely used to study the optic nerves and exclude compressive lesions, infarctions, or inflammation. However, the small caliber and divergent oblique orientations of the optic nerves make it challenging to characterize them well with conventional MRI, especially since adjacent air-filled bony structures distort the MRI signal and motion is a problem even in cooperative, healthy volunteers. EVIDENCE ACQUISITION: Over the past 3 years we have experimented with multiple novel MRI approaches and sequences to better characterize the optic nerves. The perfect MRI protocol would be quantitative and sensitive to subtle optic nerve pathologic changes, provide high spatial resolution, be rapidly acquired, and resistant to motion degradation. RESULTS: This review provides an update of recent MRI sequence innovations for the optic nerves being currently translated into clinical practice. Methods discussed include rapid MRI with compressed sensing or simultaneous multislice approaches, postprocessing techniques for quantitative T2 mapping or track density imaging, and multiple MRI sequences for measuring diffusion in the optic nerves. CONCLUSIONS: Recently-developed orbit-specific MRI coils, quantitative sequences, and rapid acquisition techniques can improve our future ability to study optic nerve pathologies noninvasively. As advanced MRI becomes more proficient at characterizing the optic nerves, its role in the clinical management of patients should increase.
Authors: Michael Xiang; Cynthia Chan; Lei Wang; Khushboo Jani; Samantha J Holdsworth; Michael Iv; Erqi L Pollom; Scott G Soltys Journal: Br J Radiol Date: 2019-05-22 Impact factor: 3.039
Authors: Jeffrey R Sims; Anna M Chen; Zhe Sun; Wenyu Deng; Nicole A Colwell; Max K Colbert; Jingyuan Zhu; Anoop Sainulabdeen; Muneeb A Faiq; Ji Won Bang; Kevin C Chan Journal: J Magn Reson Imaging Date: 2020-10-02 Impact factor: 4.813
Authors: Sara Collorone; Baris Kanber; Leen Hashem; Niamh Cawley; Ferran Prados; Indran Davagnanam; Frederik Barkhof; Olga Ciccarelli; Ahmed Toosy Journal: J Neuroophthalmol Date: 2021-09-23 Impact factor: 4.415