A new adaptive cerebral interface has just been designed by Carmen Vidaurre Arbizu, an engineer from Pamplona, Spain. The design is completely adaptive and so reduces the time required to become a skilled operator and enhances the control of the user.
The aim of a cerebral interface or brain–computer interface (BCI) is to control technology by thought. The technology supports individuals with communication problems, allowing them to relate to their surroundings more effectively via electrophysiological signals from the brain. Vidaurre’s design utilizes electroencephalograms of the individual, however, there are other recording systems that can be used.
Previously the user and the interface acted in an inter-dependent manner. However, Vidaurre’s system provides feedback to the user. The system consists of two in-line adaptive classifications within a completely adaptive interface and is capable of supplying feedback to inexpert individuals in the first stages of its use. With this system, the interface and the individual adjust to each other, one learning from the other in a reciprocal manner. In this way it has been possible to eliminate the initial trial sessions that previously took place without feedback, thus diminishing the total skill acquisition time and enabling individuals to adapt to an operating strategy directly with the use of feedback.
Trials carried out on individuals without prior experience demonstrate that the majority of the population is capable of learning to control an adaptive BCI. In fact, in the trials undertaken with 30 people in Austria and Pamplona, it was found that 20 had been able to control the interface ‘very well’ within 4 h.
Device to eradicate the pain of migraine before it begins
An electronic device known as transcranial magnetic stimulation (TMS) is set to become the next form of relief for the millions of people who suffer from debilitating migraine pain.
Initial studies to test the device, led by the Ohio State University Medical Center, USA neurology investigators, have demonstrated it to be effective in eliminating migraine pain when administered at the point of onset. A subsequent study will examine the device in a larger population.
The device acts by interrupting the aura phase of the migraine – the phase that precedes the headache. Migraine sufferers often describe ‘seeing’ showers of shooting stars, flashing lights and experiencing loss of vision, weakness, tingling or confusion. This is usually followed by a throbbing headache, nausea and vomiting.
Yousef Mohammad, the principal investigator of the study said, “Perhaps the most significant effect of using the TMS device was on the 2-h symptom assessment, with 84% of the episodes in patients using the TMS occurring without noise sensitivity. Work functioning also improved, and there were no side effects reported.”
The device sends a strong electric current through a metal coil, which creates an intense magnetic field for approximately 1 ms. This magnetic pulse, when held against a person’s head, creates an electric current in the neurons of the brain, interrupting the aura before it results in a throbbing headache.
“The device’s pulses are painless. The patients have felt a little pressure, but that’s all”, said Mohammad.
“In our study sample, 69% of the TMS-related headaches reported to have either no or mild pain at the 2-h post-treatment point compared with 48% of the placebo group. In addition, 42% of the TMS-treated patients graded their headache response, without symptoms, as very good or excellent compared with 26% for the placebo group. These are very encouraging results.”
Up until the late 1990s it was believed that migraine headaches began with vascular constriction, which results in an aura, followed by vascular dilation, which leads to a throbbing headache. However, it was then discovered that neuronal electrical hyper-excitability resulted in a throbbing headache. This new understanding of the migraine mechanism was instrumental in the development of the TMS device.
First implant of World Heart’s next-generation rotary VAD a success
World Heart Corporation’s first human implant of its advanced rotary ventricular assist device (VAD) took place on March 8, 2006 and proved to be successful. The patient was discharged from the hospital after the VAD was explanted, having recovered sufficient cardiac function to restore him to a good quality of life.
The surgical team whose members had completed training at WorldHeart’s Salt Lake City facility, successfully implanted the device into a 67-year-old man with advanced congestive heart failure in early March, as part of an operation that included heart valve repair as well as a coronary artery bypass graft.
“Our surgical and clinical team is extremely pleased to perform the first implant of this unique new device”, said Antonis Pitsis, cardiac surgeon and Director of the Thessaloniki Heart Institute at St Luke’s Hospital, and principal clinical investigator of the feasibility trial. “The WorldHeart rotary VAD has, thus far met our high expectations and it has been particularly rewarding to see the patient doing well. The patient is enjoying interacting with his family.”
James Long, cardiac surgeon and Director of the Utah Artificial Heart Program at LDS Hospital in Salt Lake City, UT, USA, assisted with the operation. Long said, “It is encouraging to see the field of long-term mechanical circulatory support expand with exciting new technologies being utilized in new high-quality centers worldwide. I believe growth of the field will be enhanced by the introduction and validation of such next-generation devices designed for ease of use, enhanced quality of life and improvements with performance, blood compatibility and durability.”
The WorldHeart rotary VAD is the only bearingless, fully magnetically levitated implantable centrifugal rotary pump in clinical trials. It is an advanced, next-generation, continuous flow pump that uses magnetic levitation to fully suspend the spinning rotor. The pump’s proprietary levitation technology employs a combination of passive magnetic suspension and single-axis active control, which is expected to provide optimal system simplicity and reliability.
Unlike most rotary pumps currently in clinical trials, it does not rely on either a mechanical bearing or a film of blood (blood bearing) to support the rotor. Relative to pumps with blood or mechanical bearings, full magnetic levitation eliminates wear mechanisms within the pump and is expected to provide improved blood compatibility by allowing greater clearances and more favorable, obstruction-free, blood flow around the rotor.
A ground-breaking dissolvable scaffold to grow new skin
A new ground-breaking dissolvable scaffold for growing new areas of skin has been developed by a team of chemists, materials scientists and tissue engineers at the University of Sheffield, UK, with funding from the Engineering and Physical Sciences Research Council. It is thought that the new approach could provide a safer, more effective way of treating burns, diabetic ulcers and similar injuries. The ultrafine, 3D scaffold is made from specially developed polymers, and although it looks similar to tissue paper, its fibers are 100-times finer. Before the scaffold is placed, the patient’s own skin cells are introduced, in order for them to attach themselves, multiplying and growing to sufficiently cover the scaffold. When applied to the wound, after a period of 6–8 weeks the scaffold disintegrated leaving the patients own cells in place.
The approach was initially designed for patients with extensive burns when there is insufficient skin remaining to produce the necessary grafts. Bovine collagen or skin from human donors is currently used in these cases; however such approaches can lead to rejection issues and other health risks.
“Simplicity is the key”, says Tony Ryan, who is leading the team. “Previous attempts to find better ways of encouraging skin cell growth have used chemical additives and other elaborate techniques to produce scaffolds, but their success has been limited. We’ve found that skin cells are actually very ‘smart’ – it’s in their DNA to sort themselves into the right arrangement. They just need a comparatively uncomplicated scaffold (and each other) to help them grow in a safe, natural way.”
Since simple polymers can be used in this approach the materials are already approved for medical applications.
The process is based upon the already established technique of electrospinning. However, the team have made their own key advance in developing, from the same biodegradable polymers, aligned fiber mats to promote nerve or tendon growth.
The next step, hopefully in the next few years, is to develop the technology for clinical use. In addition it is hoped that the technology will be used to grow skin in the laboratory for the testing of cosmetics and similar products.
“Ultimately, we can envisage treatment of burns victims and the undertaking of reconstructive surgery using the scaffold and the patient’s own skin to produce bespoke skin for that patient”, says Ryan. “As an accident-prone mountain biker, I find that prospect very attractive.”
FreeStyle Navigator™ Continuous Glucose Monitoring System study demonstrates accuracy and stability
The FreeStyle Navigator™ Continuous Glucose Monitoring System from Abbott Diabetes Care is an investigational device under US FDA review. The system includes a 5-day sensor, a transmitter and a wireless receiver with a built-in FreeStyle Blood Glucose Monitoring System. The system is designed to provide glucose readings once per minute, high/low glucose alarms and projected glucose alarms. The results of a new study to assess the device met their primary end points and demonstrated accuracy and stability over a 5-day period of use.
The study assessed the accuracy of the device in 58 subjects aged between 18 and 64 years. The device measurements were compared with a laboratory reference. A Clarke Error Grid was used to compare the measurements generated from both the device and the labarory reference. The variance between the two scores was placed on the grid, with zones labeled A, B, C, D or E. Points in zone A are akin to those generated in the laboratory, while points in zone B are clinically acceptable and points in zones C, D and E are progressively less accurate.
“Frequent and accurate glucose monitoring is an essential element of achieving tight glycemic control. The accuracy, particularly in the A zone, of continuous glucose monitoring sensors is critical to assessing the benefits that patients can derive from the technology,” said William L Clarke, Professor of pediatrics at the University of Virginia Health System, VA, USA. “In clinical studies presented by Abbott earlier this week, the FreeStyle Navigator system, under development, has set a new threshold for point glucose accuracy in a continuous glucose monitoring system.”
“We look forward to making FreeStyle Navigator available to people with diabetes and we’re very pleased that the system continues to demonstrate excellent accuracy in clinical studies”, said Ed Fiorentino, President, Abbott Diabetes Care.