(Press-News.org) Each year, more than 35,000 patients in the United States are implanted with spinal cord stimulators to treat chronic pain. Unfortunately, up to half of such patients receive only very limited pain relief. To help more patients, scientists are developing a new device to deliver therapeutic stimulation in a more targeted way, reaching nerve fibers deep within the spinal cord.
Standard devices, first introduced in 1967, work by delivering a low electrical current to the spinal cord that interferes with the body's pain signals. Such devices, however, are only able to deliver therapeutic current to a thin layer of nerve fibers along the outside of the spinal cord. That's because the electrodes delivering the current are placed within the cerebrospinal fluid, which is itself conductive and so dissipates some of the current.
The new device, called the Human Spinal Cord Modulation System (HSCMS), is designed to be in direct contact with the spinal cord, held in place by a small loop of wire. Because the spinal cord moves during normal patient activity, that loop has to exert enough pressure for the HSCMS to stay in contact with the spinal cord but not so much that the pressure restricts blood flow or causes direct injury.
To test the pressure exerted by the HSCMS's design, researchers attached the device to a silicone model of the spinal cord previously developed to have the same biomechanical characteristics as living tissue. They then slowly compressed the loop, measuring the pressure exerted on the silicone model. The results, which were accepted for publication in the American Institute of Physics (AIP) Journal of Applied Physics, show the device's loop design exerts pressure at a similar level as is normally found on the spinal cords of healthy people, and so passes an important safety test for further development of the device.
### Article: "Dynamic loading characteristics of an intradural spinal cord stimulator" is published in the Journal of Applied Physics.
Link: http://jap.aip.org/resource/1/japiau/v113/i2/p026103_s1
Authors:
M. S. Oliynyk (1), G. T. Gillies(1,2), H. Oya (3), S. Wilson (3), C. G. Reddy (3), and
M. A. Howard III (3)
(1) University of Virginia, Department of Biomedical Engineering
(2) University of Virginia, Department of Physics
(3) University of Iowa Hospitals and Clinics
Relieving chronic pain
2013-03-25
ELSE PRESS RELEASES FROM THIS DATE:
Using fluctuating wind power
2013-03-25
Incorporating wind power into existing power grids is challenging because fluctuating wind speed and direction means turbines generate power inconsistently. Coupled with customers' varying power demand, many wind-farm managers end up wasting power-generation capacity and limiting the service life of turbines through active control – including fully stopping turbines – in order to avoid any possible damage to the power grid from spikes in supply. In a paper published in the American Institute of Physics' Journal of Renewable and Sustainable Energy, researchers propose a ...
Ultra-precision positioning
2013-03-25
Ultra-precision positioning is required for the success of many scientific applications, including manufacturing semiconductors, aligning optics and manipulating cells. One of the challenges of ultra-precise positioning is providing sufficient torque through small, precise angles. In a paper accepted for publication in the Review of Scientific Instruments, a journal of the American Institute of Physics, researchers describe a new rotary actuator that accurately delivers more torque than previous devices.
Like many other ultra-precise rotary actuators, the new device's ...
EARTH: Scientists reopen a lunar cold case
2013-03-25
Alexandria, VA – When Apollo 17 splashed down in the Pacific Ocean on Dec. 19, 1972, it ended an era of manned spaceflight to the moon. The science, however, continues.
Armed with analytical techniques not available in the 1970s, researchers around the country have been re-examining the more than 380 kilograms of lunar rocks collected four decades ago during the Apollo missions. Using new investigations, such as petrographic and chemical composition studies and updated solar radiation and engineering measurements, these "cold case" scientists, many of them young innovators, ...
Scientists propose alternative method for the study of ions
2013-03-25
Scientists at the Department of Physics of the University of Oulu have teamed up with scientists in France, Russia and Japan to propose a new experimental method for researching positively charged ions. The study, In the Finnish side carried out by postdoctoral researcher Saana-Maija Huttula and Professor Marko Huttula in Oulu, was published in Physical Review Letters on 12 March 2013. The study involved investigating the electronic structure of the argon ions using synchrotron radiation. The proposed theoretical simulations were done using methods developed by an electron ...
Research: Women over 40 still need effective contraception
2013-03-25
Women reaching the age of 40 tend to be less vigilant about birth control because they think the risk of pregnancy is low – or that birth control can cause health problems - but a review of the evidence by a team that includes a Women & Infants Hospital of Rhode Island physician recently underscored the need to be vigilant about contraception even in perimenopause.
"Despite declining fertility, women over age 40 still require effective contraception if they want to avoid pregnancy," according to Rebecca H. Allen, MD, MPH, of Women & Infants' Department of Obstetrics and ...
Businesses increase revenue with social media
2013-03-25
Researchers at Aalto University, the University at Buffalo, and Texas A&M University have proven a link between customers' use of social media and higher revenue.
Now there is proof that customers who engage with a business through social media contribute more to the bottom line than customers who do not, said Ashish Kumar, assistant professor of marketing at Aalto University.
Our study showed that social media activities help strengthen the bond between the customer and the firm. Participating customers on a firm's social media site contribute 5.6% more revenue and ...
How can we prepare better for emergencies?
2013-03-25
Well designed and planned exercises are essential to ensure that the UK can respond effectively to emergencies of all kinds, according to research funded by the Economic and Social Research Council (ESRC). The emergencies may take the form of a terrorist attack, flooding, pandemic flu, rail or air disaster - or any major disruptive event requiring an emergency response.
The number of such exercises taking place across the UK each year within what the researchers call the 'resilience community' - including emergency services, local authorities, central government departments ...
Laser empties atoms from the inside out
2013-03-25
An international team of plasma physicists has used one of the world's most powerful lasers to create highly unusual plasma composed of hollow atoms.
The experimental work led by scientists from the University of York, UK and the Joint Institute for High Temperatures of Russian Academy of Sciences demonstrated that it is possible to remove the two most deeply bound electrons from atoms, emptying the inner most quantum shell and leading to a distinctive plasma state.
The experiment was carried out using the petawatt laser at the Central Laser Facility at the Science and ...
Ephemeral vacuum particles induce speed-of-light fluctuations
2013-03-25
Two forthcoming EPJ D papers challenge established wisdom about the nature of vacuum. In one paper, Marcel Urban from the University of Paris-Sud, located in Orsay, France and his colleagues identified a quantum level mechanism for interpreting vacuum as being filled with pairs of virtual particles with fluctuating energy values. As a result, the inherent characteristics of vacuum, like the speed of light, may not be a constant after all, but fluctuate. Meanwhile, in another study, Gerd Leuchs and Luis L. Sánchez-Soto, from the Max Planck Institute for the Physics of Light ...
Glass-blowers at a nano scale
2013-03-25
Have you ever thrown into the fire - even if you shouldn't have - an empty packet of crisps? The outcome is striking: the plastic shrivels and bends into itself, until it turns into a small crumpled and blackened ball. This phenomenon is explained by the tendency of materials to pick up their original features in the presence of the right stimulus. Hence, this usually happens when heating materials that were originally shaped at high temperatures and cooled afterwards.
EPFL researchers realized that this phenomenon occurred to ultrathin quartz tubes (capillary tubes) ...