
The use of ultrasound in medical technology is becoming more and more prevalent every day. They have been reported to be used to treat patients with type 2 diabetes & waking coma patients.
And now, a team of researchers at the University of Southern California (USC) is developing a new treatment model that can stimulate retinal neurons with ultrasound.
With the growing rate of aged humans across the world, a `silver tsunami’ is predicted through experts, and with regards to this, it isn’t always unexpected that the number of humans with visible impairment is also anticipated to surge.
In many cases, a degenerative disease of the retina, that is, progressive degeneration of the retina’s photosensitive receptors, is expected. There is still no non-invasive treatment for this disorder, so new technologies are still needed to restore the loss of vision.
The treatment currently used by ophthalmologists is invasive surgery, which requires implantation of an electrode device inside the eye. Therefore, this novel approach could be a non-surgical solution to facilitate the treatment of vision loss.
“Now we are working on animals to replace electrical stimulation with ultrasound stimulation,” said Qifa Zhou, professor of biomedical engineering & ophthalmology at the University of Southern California. He is also leading the research with Mark S. Humayun, co-inventor of Argus II, the world’s first artificial retina.
Stimulating the retina
Treatment is performed using a wearable ultrasound device that stimulates the retina by applying mechanical pressure to the eye. So the neurons will-be activated and will send signals to brain.
“The neurons in the retina of the eye have mechanosensitive channels that respond to mechanical stimuli,” says Gancy Lu, is a Ph.D student in Zhou’s lab. “These neurons activated when we use ultrasound to generate mechanical pressure.”
To test the approach, the researchers used blind rats and stimulated their eyes using high-frequency ultrasound. They projected patterns onto specific areas of the eye, but because the rats couldn’t tell the scientists what they were seeing, the team used an array of electrodes to measure activity in the rat’s visual cortex. The results showed that the rats perceived the visualization projected to the eye.
The next step would be to test the method in non-human primates and then apply ultrasound waves to wearable contact lenses. “Currently, we use a transducer places in the front of the eye of mice to send ultrasound signals to the retina, but the ultimate goal is to create a wireless lens transducer,” Zhou said.
The study was published in the journal BME Fronters.