Injectable Electronic Meshes
A team of Harvard scientists has created 2-by-4-centimeter meshes of silicone nanowires that are so thin and flexible they can be placed in a saline solution, drawn up into a syringe and injected into a living host.
“The meshes rolled up like tiny scrolls when they were drawn into the needle,” IEEE’s Spectrum reports. After injection, they slowly resume their natural shape.
In mouse models, the nanowire meshes are attached to conductive polymer leads going outside the mice’s heads for electronic access. The researchers note that signal activity along the leads increased over three months of testing. Brain cells migrate across the mesh’s surface, the scientists report, suggesting the technology could be used to help repair stroke injury or other damage in the brain. Other possible uses include the control of prosthetics, the researchers say.
MicroTransponder Vivistim System
Now being tested in mice, these silicone devices may one day help repair brain damage.
Commonly used to treat patients with depression and epilepsy, vagus nerve stimulation (VNS) is now part of a clinical trial for stroke patients. The Vivistim System, made by MicroTransponder, consists of an implantable VNS device and a wireless controller operated by a therapist.
While the patient undergoes physical rehabilitation, the therapist watches for successful completion of a prescribed task and activates the stimulator. The act of neural stimulation, combined with a specific muscle movement, helps the patient rebuild motor neuron circuits, enabling the brain to relearn how to direct muscles to perform those movements.
MicroTransponder has a similar VNS system, Serenity, on the market for treatment of tinnitus.
Gastric Emptying Breath Test
This vagus nerve stimulator treats upper-body movement deficits in stroke survivors.
This test provides a minimally invasive diagnostic solution for gastroparesis.
Gastroparesis, a disease in which the stomach does not properly move food into the small intestine, causes numerous problems, including nausea, reflux and vomiting, dehydration, and malnutrition. Endoscopy, X-rays and emptying tests using radioactive material are the traditional diagnostic tools. However, the FDA has approved a test that is noninvasive, except for food products ingested, and does not involve radiation.
The Gastric Emptying Breath Test (GEBT) consists of powdered egg, saltine crackers and Spirulina, a nutritional supplement that contains enriched blue-green algae, which can be measured by breath tests.
The patient fasts overnight, then, after an initial breath test, eats the GEBT meal. Breath samples at periodic intervals help clinicians determine how fast the stomach is emptying. The FDA notes that this test, developed by Advanced Breath Diagnostics, LLC, can be used in any clinical setting, requires no specialized training and is harmless except to patients with food allergies.