New technique revolutionizes eye imaging

By Esther Nakkazi

A new study shows it is possible to take magnetic resonance imaging (MRI) pictures of the eye as it moves across a scene, an artwork, or as we read.

Eye motion is a major confound for MRI in neuroscience or ophthalmology and the technique will open new possibilities in fields such as sleep and dream research and more generally for understanding brain activity in disorders of consciousness.

The new MRI technique published in the journal Progress in Neurobiology reveals for the first time simultaneous details about the eye, its musculature, and oculomotor properties and analysis of its anatomy and neurophysiology according to a press release from the centre Hospitalier universitaire Vaudois.

The study conducted by the Radiology Department of the University Hospital Center and University of Lausanne (CHUV-UNIL) as well as Fondation Asile des aveugles (FAA) is based on recent advances in MRI that allow for taking many snapshots of an object that repeatedly moves, such as the beating heart or moving eye.

Researchers can also study eye position even when the eyes are closed which would open new possibilities in fields such as sleep and dream research as well as more generally for understanding brain activity in disorders of consciousness.

“This is the first time scientists are able to image the eye while it moves, establishing a link between behavior and anatomy," says Dr. Benedetta Franceschielo, a post-doctoral fellow and lead author of the study, who works in the team of Professor Micah Murray, principal investigator of this project.

"This will open a new field of ophthalmic MRI, where we will be finally able to combine multiple assessments within a single, fast, session. The applications are infinite. They span from medical diagnosis to eye-brain mechanisms,” explains Dr. Franceschielo.

Eye movements are a major obstacle for imaging the eye, especially in the cases of children, the elderly, or patients with eye disease. The necessity to fixate ordinarily restricts the range of compliant participants; something often challenging for pediatric and aged populations alike.

“We have removed the onus of maintaining central fixation. Because we used standard MRI equipment and eye-tracking hardware, the approach we have developed and validated is readily deployed to the broad scientific community and impacts not only the breadth of participant inclusion but also the extent of naturalistic paradigms that can be investigated," said Professor Murray about the wider impact of this new technological advancement.

“Five years ago, this research would not have been feasible. Only at the confluence of staggering progress in hardware, software, and methodology development in a university setting did this become possible,” says Professor Stuber.

Supported by the Swiss National Science Foundation, the team of researchers is composed of neuroscientists, engineers, mathematicians, and optometrists from laboratories of Professors Micah Murray and Matthias Stuber at the Radiology Department of the CHUV- UNIL, the Center for Biomedical Imaging (CIBM), and FAA.

The team is now refining this technique to optimize it and make it versatile for clinical application in the field of ophthalmology. This invention not only represents a turning point in the way scientists study the eyes but also in cognitive neuroscience.

It has also recently demonstrated its value by allowing the creation of new protocols both in the field of diagnosis in ophthalmology as well as in visual rehabilitation.

Reference: Progress in Neurobiology.
Author: Benedetta Franceschiello, Lorenzo Di Sopra, Astrid Minier, Silvio Ionta, David Zeugin, Michael P.Notter, Jessica A.M.Bastianseen, Joao Jorge, Jérôme Yerly, Mat- thias Stuber, Micah M.Murray.