Seizures travel through the brain within seconds, making it difficult to capture them in detail. To overcome this challenge, researchers developed a new high-resolution light-sheet imaging system that is fast enough to image seizure propagation in 3D within the brain of larval zebrafish.
We have developed a light-sheet microscope that corrects for aberrations, a flaw in the way microscopes form images, in real time and enables rapid volumetric imaging. While most imaging of seizure events in zebrafish captures only 2D images, our system allows for 3D high-resolution imaging in larger volumes than previously possible. ”
Peter Kner, Research Team Leader, University of Georgia
Published in the journal of Optica Publishing Group Biomedical Optics ExpressThe researchers show that the new microscope system can capture volumes of up to 499 × 499 × 150 microns3 at a rate of 4 volumes per second with near-diffraction-limited resolution. They used this system to observe how seizures spread through the nervous system of zebrafish larvae, which are commonly used in neuroscience research.
“The detailed imaging information obtained from our high-speed volumetric imaging technology provides new insights into the mechanisms of seizure formation and propagation and may aid in the development of more effective treatments,” said Kuner. “More generally, this approach could help improve our understanding of how the brain works and provide information on treatments for a variety of brain diseases and disorders.”
Faster 3D imaging
New research has begun with the aim of understanding how seizures spread in the brain and how genes are affected. gado 1b affect this process. The gad1b gene helps regulate the neurotransmitter GABA, which is important for brain development and signal transmission. After capturing normal zebrafish and zebrafish seizure activity using 2D light sheet microscopy, gado 1b The researchers wanted to visualize in 3D how these events unfold across the brain.
Light-sheet microscopy uses a thin sheet of light to illuminate the sample from the side, greatly reducing unfocused background light compared to wide-field microscopy. It is also much faster and less phototoxic than techniques such as confocal microscopy, which also blocks out-of-focus light.
In previous work, researchers built a light-sheet microscope system with a wide field of view and sensorless adaptive optics. This is an approach that calculates optical corrections directly from image quality measurements. However, this system took approximately 1.75 seconds to retrieve one raw volume. This is not fast enough to capture rapidly changing brain activity in 3D.
To create a faster imaging system, the researchers used electrically adjustable lenses to rapidly move the focal plane within the sample. While this sped up image acquisition, the researchers also needed to develop a way to synchronize millisecond-scale adaptive optics updates with the microscope’s camera and scanning components. These improvements have made it possible to achieve continuous high-speed volumetric imaging without sacrificing image quality.
Observe brain seizures
Researchers used a new light-sheet microscope to image the propagation of induced seizures in zebrafish larvae. 600 volumes were acquired continuously in 2.5 minutes. This is 7 times faster than the previous system.
The zebrafish images showed that the seizures originated in the posterior region of the brain, propagated anteriorly toward the optic tectum, a brain region involved in processing visual information, and then gradually subsided over tens of seconds.
Next, the researchers plan to use the system to image more samples, such as zebrafish. gado 1b gene. They are also working on a direct wavefront sensing approach to correct aberrations in zebrafish samples as well as optical systems.
sauce:
Reference magazines:
Liu, B. others. (2026). High-speed volumetric imaging of a zebrafish seizure model using adaptive optics light-sheet microscopy. Biomedical Optics Express. DOI: 10.1364/BOE.596096. https://opg.optica.org/boe/fulltext.cfm?uri=boe-17-8-4216
