Robust mouse pattern electroretinograms derived simultaneously from each eye using a common snout electrode.

Area of Science:

• Neuroscience
• Ophthalmology
• Animal Models

Background:

• Pattern electroretinograms (PERGs) are crucial for assessing retinal ganglion cell (RGC) function, particularly in mouse models of optic nerve diseases.
• Current PERG recording methods can be invasive or time-consuming, limiting their application in complex experimental designs.

Purpose of the Study:

• To develop and validate a novel, non-invasive binocular stimulation method for simultaneous PERG recording from both eyes in mice.
• To assess the reliability, amplitude, and signal source of the novel binocular snout PERG technique.

Main Methods:

• Simultaneous PERG recording from both eyes in anesthetized mice using subcutaneous needles placed on the snout.
• Binocular stimulation with contrast-reversing gratings presented on alternating frequency LED tablets.
• Signal retrieval via single-channel acquisition and phase-locking average, with optic nerve crush used to confirm RGC origin.

Main Results:

• High-amplitude binocular snout PERGs were recorded with no measurable interocular cross-talk.
• The method demonstrated high reliability and low interocular asymmetry within and between sessions.
• Optic nerve crush experiments confirmed that retinal ganglion cells are the primary source of the recorded PERG signal.

Conclusions:

• The binocular snout PERG method offers a significant advancement in simplicity and speed for measuring RGC function in mice.
• This technique overcomes limitations of corneal electrodes, facilitating invasive procedures and inter-eye comparisons.
• The binocular snout PERG is a sensitive, reliable, and efficient tool for research in glaucoma and optic nerve disease models.