Saikat Sengupta1,2, David S Smith1,2, Alex K Smith3, E Brian Welch1,2,4, Seth A Smith1,2,4. 1. Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, United States. 2. Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, United States. 3. The Centre for Functional MRI of the Brain, The University of Oxford, Oxford, United Kingdom. 4. Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, United States.
Abstract
Purpose: The eye and its accessory structures, the optic nerve and the extraocular muscles, form a complex dynamic system. In vivo magnetic resonance imaging (MRI) of this system in motion can have substantial benefits in understanding oculomotor functioning in health and disease, but has been restricted to date to imaging of static gazes only. The purpose of this work was to develop a technique to image the eye and its accessory visual structures in motion. Methods: Dynamic imaging of the eye was developed on a 3-Tesla MRI scanner, based on a golden angle radial sequence that allows freely selectable frame-rate and temporal-span image reconstructions from the same acquired data set. Retrospective image reconstructions at a chosen frame rate of 57 ms per image yielded high-quality in vivo movies of various eye motion tasks performed in the scanner. Motion analysis was performed for a left-right version task where motion paths, lengths, and strains/globe angle of the medial and lateral extraocular muscles and the optic nerves were estimated. Results: Offline image reconstructions resulted in dynamic images of bilateral visual structures of healthy adults in only ∼15-s imaging time. Qualitative and quantitative analyses of the motion enabled estimation of trajectories, lengths, and strains on the optic nerves and extraocular muscles at very high frame rates of ∼18 frames/s. Conclusions: This work presents an MRI technique that enables high-frame-rate dynamic imaging of the eyes and orbital structures. The presented sequence has the potential to be used in furthering the understanding of oculomotor mechanics in vivo, both in health and disease.
Purpose: The eye and its accessory structures, the optic nerve and the extraocular muscles, form a complex dynamic system. In vivo magnetic resonance imaging (MRI) of this system in motion can have substantial benefits in understanding oculomotor functioning in health and disease, but has been restricted to date to imaging of static gazes only. The purpose of this work was to develop a technique to image the eye and its accessory visual structures in motion. Methods: Dynamic imaging of the eye was developed on a 3-Tesla MRI scanner, based on a golden angle radial sequence that allows freely selectable frame-rate and temporal-span image reconstructions from the same acquired data set. Retrospective image reconstructions at a chosen frame rate of 57 ms per image yielded high-quality in vivo movies of various eye motion tasks performed in the scanner. Motion analysis was performed for a left-right version task where motion paths, lengths, and strains/globe angle of the medial and lateral extraocular muscles and the optic nerves were estimated. Results: Offline image reconstructions resulted in dynamic images of bilateral visual structures of healthy adults in only ∼15-s imaging time. Qualitative and quantitative analyses of the motion enabled estimation of trajectories, lengths, and strains on the optic nerves and extraocular muscles at very high frame rates of ∼18 frames/s. Conclusions: This work presents an MRI technique that enables high-frame-rate dynamic imaging of the eyes and orbital structures. The presented sequence has the potential to be used in furthering the understanding of oculomotor mechanics in vivo, both in health and disease.
Authors: Leon C Ho; Ian A Sigal; Ning-Jiun Jan; Alexander Squires; Zion Tse; Ed X Wu; Seong-Gi Kim; Joel S Schuman; Kevin C Chan Journal: Invest Ophthalmol Vis Sci Date: 2014-08-07 Impact factor: 4.799
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: Bianca A W Hoeben; Enrica Seravalli; Amber M L Wood; Mirjam Bosman; Witold P Matysiak; John H Maduro; Astrid L H M W van Lier; Matteo Maspero; Gijsbert H Bol; Geert O Janssens Journal: Clin Transl Radiat Oncol Date: 2021-08-29