There are a few experimental challenges. For example, the presence of hair in the scalp can cause artifact in the acquired images. The age of the animal also plays a key role since the thickness of the skull is currently a limitation for the detection of deeper signals.
Many purely optical imaging techniques require an invasive procedure and can only image about one millimeter deep. With PAUSAT, we combine the advantages of both ultrasound and optical imaging. We can get both structural and functional information surrounding ischemic stroke in a completely safe and non-invasive way.
Being able to evaluate the evolution of an injury with or without treatment from the same animal at different time points allows us to collect very valuable information. And also to reduce the number of animals required for different studies. We are constantly working on ways to improve the imaging speed, depth, resolution and contrast for both photoacoustic and ultrasound imaging.
With better imaging systems, we can answer more fundamental biological questions and evaluate new experimental treatments.