Automated animal gimbal steering for retinal imaging and stimulation

Area of Science:

• Biomedical Engineering
• Ophthalmology
• Optomechanics

Background:

• Retinal imaging and stimulation in animals often requires precise alignment with ophthalmoscopes.
• Maintaining eye-ophthalmoscope alignment is challenging, especially with stationary equipment, leading to vignetting and extended imaging times.
• Current methods may cause excessive light exposure and discomfort for the animals.

Purpose of the Study:

• To introduce novel optomechanical devices for automated steering of anesthetized animals during retinal imaging and/or stimulation.
• To ensure consistent centering of the eye's entrance pupil with the ophthalmoscope's exit pupil, preventing vignetting.
• To enhance animal welfare and reduce procedural burdens in ophthalmic research.

Main Methods:

• Development of optomechanical steering devices using commercially available manual linear stages and motorized rotating components.
• Implementation of simple operating procedures for maintaining pupil alignment during imaging.
• Demonstration of the system's efficacy in mice for capturing image sequences for tiling.

Main Results:

• The proposed devices successfully steered anesthetized mice for stationary ophthalmoscope use, maintaining pupil alignment.
• The system facilitated image sequence capture for tiling, comparable to microscopy techniques.
• The automated steering reduced imaging time and retinal light exposure.

Conclusions:

• Optomechanical steering devices offer a practical solution for precise retinal imaging and stimulation in animal models.
• This technology is adaptable to various animal species, imaging modalities, and explanted eyes.
• The system improves efficiency, reduces light exposure, and enhances animal welfare in ophthalmic research.