Detecting visual deficits in retinal degeneration mice using photoacoustic tomography

We established a photoacoustic tomography and ultrasound imaging system capable of resolving visually evoked hemodynamic responses in the cortical and subcortical visual regions of the brains of freely behaving mice. By searching for anatomical landmarks in the US imaging planes, we can locate brain regions of interest and continuously record HR in these regions. The system was examined in retinal degeneration mice using a 60-second protocol and in Claudin 5 knockdown mice and mice with vision deficits using a 100-minute-long vision research protocol. We found that: 1) visually evoked HR amplitudes increase as visual stimulation intensity increases in both scotopic and photopic conditions; and 2) HR amplitudes increase during the light adaptation time course.