Posts tagged stroke
Articles and news from the latest research reports.
Doctors aim to help stroke patients overcome disability by helping rewire their brains
Researchers at the University of Glasgow are hoping to help victims of stroke to overcome physical disabilities by helping their brains to ‘rewire’ themselves.
Doctors and scientists from the Institute of Cardiovascular and Medical Sciences will undertake the world’s first in-human trial of vagus nerve stimulation in stroke patients. Stroke can result in the loss of brain tissue and negatively affect various bodily functions from speech to movement, depending on the location of the stroke.
The study, which will be carried out at the Western Infirmary in Glasgow, will recruit 20 patients who suffered a stroke around six months ago and who have been left with poor arm function as a result.
Each participant will receive three one-hour sessions of intensive physiotherapy each week for six weeks to help improve their arm function.
Half of the group will also receive an implanted Vivistim device, a vagus nerve stimulator, which connects to the vagus nerve in the neck. When they are receiving physiotherapy to help improve their arm, the device will stimulate the nerve.
It is hoped that this will stimulate release of the brain’s own chemicals, called neurotransmitters, that will help the brain form new neural connections which might improve participants ability to use their arm.
Lead researcher Dr Jesse Dawson, a Stroke Specialist and Clinical Senior Lecturer in Medicine, said: “When the brain is damaged by stroke, important neural connections that control different parts of the body can be damaged which impairs function.
“Evidence from animal studies suggests that vagus nerve stimulation could cause the release of neurotransmitters which help facilitate neural plasticity and help people re-learn how to use their arms after stroke; particularly if stimulation is paired with specific tasks. A slightly different type of vagus nerve stimulation is already successfully used to manage conditions such as depression and epilepsy.
“This study is designed to provide evidence to support whether this is the case after stroke but our primary aim is to assess feasibility of vagus nerve stimulation after stroke.
“It remains to be seen how much we can improve function, but if we can help people perform even small actions again, like being able to hold a cup of tea, it would greatly improve their quality of life.”
(Source: gla.ac.uk)
Stem cells aid recovery from stroke
Stem cells from bone marrow or fat improve recovery after stroke in rats, finds a study published in BioMed Central’s open access journal Stem Cell Research & Therapy. Treatment with stem cells improved the amount of brain and nerve repair and the ability of the animals to complete behavioural tasks.
Stem cell therapy holds promise for patients but there are many questions which need to be answered, regarding treatment protocols and which cell types to use. This research attempts to address some of these questions.
Rats were treated intravenously with stem cells or saline 30 minutes after a stroke. At 24 hours after stroke the stem cell treated rats showed a better functional recovery. By two weeks these animals had near normal scores in the tests. This improvement was seen even though the stem cells did not appear to migrate to the damaged area of brain. The treated rats also had higher levels of biomarkers implicated in brain repair including, the growth factor VEGF.
A positive result was seen for both fat (adipose) and bone-marrow derived stem cells. Dr Exuperio Díez-Tejedor from La Paz University Hospital, explained, “Improved recovery was seen regardless of origin of the stem cells, which may increase the usefulness of this treatment in human trials. Adipose-derived cells in particular are abundant and easy to collect without invasive surgery.”
(Source: biomedcentral.com)
Stroke Survivors with PTSD More Likely to Avoid Treatment
A new survey of stroke survivors has shown that those with post-traumatic stress disorder (PTSD) are less likely to adhere to treatment regimens that reduce the risk of an additional stroke. Researchers found that 65 percent of stroke survivors with PTSD failed to adhere to treatment, compared with 33 percent of those without PTSD. The survey also suggests that nonadherence in PTSD patients is partly explained by increased ambivalence toward medication. Among stroke survivors with PTSD, approximately one in three (38 percent) had concerns about their medications. Results of the study, led by Columbia University Medical Center researchers, are published today in the British Journal of Health Psychology.
According to data from the American Stroke Association, nearly 795,000 Americans each year suffer a new or recurrent stroke. Stroke is the fourth-leading cause of death and the top cause of disability in the United States. Survivors of strokes are often prescribed treatment regiments, including antiplatelet agents, antihypertensive agents, and statins, which help reduce the risk of subsequent strokes. Previous research has shown that PTSD triggered by medical events—which affects 18 percent of stroke survivors—may impair recovery.
“Unfortunately, too many stroke survivors are not compliant with these regimens, even though we know that adherence to post-stroke treatment regimens is one of the most important components of reducing the risk of a future stroke,” said Ian M. Kronish, MD, MPH, assistant professor of medicine (Center for Behavioral Cardiovascular Health) and one of the study’s authors.
“For those with PTSD, this study shows that concerns about medications are a significant barrier to treatment adherence. Stroke survivors should be assessed for concerns about medications and PTSD symptoms, so that interventions may be introduced as early as possible to get patients back on track to avoid future stroke events.”
When the mind controls the machines
Stroke survivors, as well as patients suffering from other serious conditions, may have to deal with the partial or complete inability to move one or more of their limbs. In the most severe cases, the sufferer may become fully paralyzed and in need of permanent assistance.
The TOBI project (Tools for brain-computer interaction) is financed by the European Commission under the Seventh Framework Programme for Research (FP7) and is coordinated by EPFL. Since 2008 it has focused on the use of the signals transmitted by the brain. The electrical activity that takes place in the brain when the patient focuses on a particular task such as lifting an arm is detected by electroencephalography (EEG) through electrodes placed in a cap worn by the patient. Subsequently, a computer reads the signals and turns them into concrete actions as, for instance, moving a cursor on a screen.
Tests involving more than 100 patients
Based on this idea, researchers from thirteen institutions together with TOBI project partners have developed various technologies aimed at either obtaining better signal quality, making them clearer, or translating them into useful and functional applications. During the research, more than 100 patients or handicapped users had the opportunity to test the devices. Three of the technologies developed within the framework of TOBI were publicly presented at the closing seminar of the research program that took place in Sion from 23 to 25 January 2013.
- Robotino, for helping rebuild social ties when bedridden. Combining EEG, signal recognition, obstacle sensors and the internet, researchers have been able to develop a small robot equipped with a camera and a screen that can be controlled remotely by physically disabled people. Thanks to this device, the patient can take a virtual walk in a familiar environment, meet her/his relatives and talk to them, even if they are thousands of miles away from each other.
- Braintree, for writing texts and internet surfing. Researchers have also developed a graphical interface specially adapted for web browsing by severely disabled people. By thinking, the patient is able to move a cursor in a tree structure in order to type a character or choose a command. Depending on the specific situation, the sensors can also detect residual muscular activity to complement the management of the device.
- Functional electrical stimulation, to restore some basic mobility. Coupling EEG with electrical muscle stimulation can allow a patient to voluntarily control the movement of a paralyzed limb. In some cases, intensive training using this system has allowed the patients to regain control of the limb and keep it without assistance. A report on this technique can be seen in this video.
The results of the TOBI research program have restored patients’ hope. They will constitute the basis of subsequent developments to be conducted among the research partners or at industrial level. As for EPFL, such results will be the core of its health research chairs at the new EPFL Valais Wallis academic cluster, which can also count on the participation and support of the SuvaCare rehabilitation clinic in Sion.
Scientists devise unique stroke assessment tool
Scientists at the University of Birmingham have devised a unique screening instrument that provides a ‘one-stop’ brain function profile of patients who have suffered stroke or other neurological damage.
The Birmingham Cognitive Screen (BCoS) can offer a visual snapshot of the cognitive abilities and deficits of an individual which can then be used to guide clinical decision making.
Following brain damage, including stroke, head injury, carbon monoxide poisoning and degenerative change, people can experience a range of cognitive problems as well as difficulty with physical movement. Cognitive problems strongly influence a patient’s ability to recover but patients are not routinely screened to detect them.
The first test of its kind, BCoS has been designed by a team of brain experts co-ordinated by Research Fellow Dr Wai-Ling Bickerton (also a chartered psychologist and occupational therapist) at the University of Birmingham in collaboration with Professors Glyn Humphreys and Jane Riddoch at Oxford University and Dana Samson at Louvain University.
Comprising a user-friendly manual, a test book, a CD containing Auditory Attention Test stimuli, a supply of examiner and examinee booklets and a zip-up pouch of test objects, the test takes 45-60 minutes and is carried out by trained health professionals and covers a range of cognitive abilities, including attention, executive function, spatial awareness, speech and language processing, action planning and control, memory, and number processing.
‘Through research outcomes supported by the Stroke Association, BCoS has already been used to successfully assess more than 1,000 stroke survivors in the West Midlands,’ explains Dr Bickerton. ‘BcoS has been validated against “standard” neuropsychological tests and assessed against measures of cognition and activities of everyday living for patients in the chronic stage.
‘The test has been designed to be highly inclusive and, as such, is an optimal tool for most stroke survivors regardless of the cognitive effects of stroke,’ she says. ‘It is also applicable to individuals with brain injury or dementia.
(Source: birmingham.ac.uk)
New Technique Helps Stroke Victims Communicate
Stroke victims affected with loss of speech caused by Broca’s aphasia have been shown to speak fluidly through the use of a process called “speech entrainment” developed by researchers at the University of South Carolina’s Arnold School of Public Health.
Aphasia, a severe communication problem caused by damage to the brain’s left hemisphere and characterized by halting speech, occurs in about one-third of people who have a stroke and affects personal and professional relationships. Using the speech entrainment technique, which involves mimicking other, patients showed significant improvement in their ability to speak.
The results of the study are published in a recent issue of the neurology journal Brain.
"This is the first time that we have seen people with Broca’s aphasia speak in fluent sentences,” said Julius Fridriksson, the study’s lead researcher and a professor with the Department of Communication Sciences and Disorders at the Arnold School. “It is a small study that gives us an understanding of how the brain functions after a stroke, and it offers hope for thousands of people who suffer strokes each year."
In Fridriksson’s study, 13 patients completed three separate behavioral tasks that were used to understand the effects of speech entrainment on speech production. During the “speech entrainment–audio visual" portion of the study, participants attempted to mimic a speaker in real-time whose mouth was made visible on the 3.5-inch screen of an iPod Touch and whose speech was heard via headphones.
The “speech entrainment–audio only” condition involved real-time mimicking speech presented via headphones with the screen of the iPod blank. During a spontaneous speech condition, patients spoke about a given topic without external aid.
Each patient also completed a three-week training phase where they practiced speech every day with the aid of speech entrainment. Overall, the training resulted in improved spontaneous speech production, something that is relatively rare in this population. Ultimately the patients were able to produce a short script about their stroke to tell to other people.
Neuroimaging results from the patient subjects have also given Fridriksson and his research team a greater understanding of the mechanism involved in speech entrainment.
"Preliminary results suggest that training with speech entrainment improves speech production in Broca’s aphasia, providing a potential therapeutic method for a disorder that has been shown to be particularly resistant to treatment," Fridriksson said.
Depressed Stroke Survivors May Face Triple the Risk of Death
People who are depressed after a stroke may have a tripled risk of dying early and four times the risk of death from stroke than people who have not experienced a stroke or depression, according to a study released today that will be presented at the American Academy of Neurology’s 65th Annual Meeting in San Diego, March 16 to 23, 2013. “Up to one in three people who have a stroke develop depression,” said study author Amytis Towfighi, MD, with the Keck School of Medicine of the University of Southern California and Rancho Los Amigos National Rehabilitation Center in Los Angeles, and a member of the American Academy of Neurology. “This is something family members can help watch for that could potentially save their loved one.”
Towfighi noted that similar associations have been found regarding depression and heart attack, but less is known about the association between stroke, depression and death.
The research included 10,550 people between the ages of 25 and 74 followed for 21 years. Of those, 73 had a stroke but did not develop depression, 48 had stroke and depression, 8,138 did not have a stroke or depression and 2,291 did not have a stroke but had depression.
After considering factors such as age, gender, race, education, income level and marital status, the risk of dying from any cause was three times higher in individuals who had stroke and depression compared to those who had not had a stroke and were not depressed. The risk of dying from stroke was four times higher among those who had a stroke and were depressed compared to people who had not had a stroke and were not depressed.
“Our research highlights the importance of screening for and treating depression in people who have experienced a stroke,” said Towfighi. “Given how common depression is after stroke, and the potential consequences of having depression, looking for signs and symptoms and addressing them may be key.”
Neurologists Describe the Most Feared and Devastating Strokes
Among the most feared and devastating strokes are ones caused by blockages in the brain’s critical basilar artery system. When not fatal, basilar artery strokes can cause devastating deficits, including head-to-toe paralysis called “locked-in syndrome.”
However, a minority of patients can have good outcomes, especially with new MRI technologies and time-sensitive treatments. These treatments include the clot-busting drug tissue plasminogen activator (tPA), and various new-generation neurothrombectomy devices, according to a review article in MedLink Neurology by three Loyola University Medical Center neurologists.
About 85 percent of strokes are ischemic, meaning they are caused by blockages in blood vessels. (The remaining strokes are caused by bleeding in the brain.) About 4 percent of all ischemic strokes are caused by blockages in the basilar artery system. The basilar artery supplies oxygen-rich blood to some of the most critical parts of the brain.
The first clinical description of a basilar artery stroke was reported in 1868, according to the MedLink article, which was written by Loyola neurologists Sarkis Morales Vidal, MD, (first author); Murray Flaster, MD, PhD; and Jose Biller, MD; and edited by Steven R. Levine, MD, of the SUNY Health Science Center.
A character in Alexandre Dumas’ novel, “The Count of Monte Cristo,” described as a “corpse with living eyes,” had what appears to be locked-in syndrome. More recently, the book and movie “The Diving Bell and the Butterfly” describe a French journalist with locked-in syndrome. The journalist was mentally intact, but able to move only his left eyelid. He composed a moving memoir by picking out one letter at a time as the alphabet was slowly recited.
The MedLink article reports that an estimated 80 percent of locked-in patients live for at least five years, and some patients have survived for more than 20 years. One survey of long-term survivors found that 86 percent reported their attention level was good, 77 percent were able to read and 66 percent could communicate with eye movements and blinking. Forty-eight percent reported their mood was good.
The review article cites a study of basilar artery stroke patients that found that a month after the stroke, one-third of patients were dead and one-third needed help for activities of daily living such as bathing, dressing and eating.
Most basilar artery strokes are caused by atherosclerosis (hardening of the arteries). The second-leading cause is clots.
Leading risk factors for basilar artery strokes are high blood pressure, diabetes, smoking, high cholesterol, coronary artery disease and peripheral vascular disease. Affected individuals tend to be over age 50. Basilar artery strokes are more common in men than in women.
Dr. Morales is an assistant professor, Dr. Flaster is an associate professor and Dr. Biller is a professor and chair in the Department of Neurology of Loyola University Chicago Stritch School of Medicine.
(Source: loyolamedicine.org)
Innovative system for the rehabilitation of people with brain damage
The Biomechanics Institute of Valencia (IBV) is currently taking part in the European project WALKX with the aim of developing an innovative rehabilitation system to improve the quality of life of people who have suffered brain damage. This system will allow home rehabilitation and improve patient’s autonomy.
WALKX is a two-year research project for the benefit of small and medium sized enterprises (SMEs), co-funded by the European Commission through the Seventh Framework Programme.
The user friendly walking training device the partners are designing will support the patient in raising from sitting to standing position and enable the patient to perform walking training and improve his/her manoeuvrability. “An upper body stabilizing and controllable supporting vest will be developed. Early in the rehabilitation process it will be used under supervision of a therapist, but with greatly reduced need for physical support from the therapists. This is intended to reduce the need for help from others and increase freedom of movement and personal autonomy of the patient”, said Ignacio Bermejo, Market Innovation Director at IBV.
One of the novelties of this device consists of a vest with attachment points on the patient’s waist in order to regulate the mobility of the trunk. Also, the device will be modular and low cost. The role of IBV in this initiative has been to define the design specifications and preclinical testing to validate the prototype. Preclinical tests are done in collaboration with the Department of Physical Medicine and Rehabilitation at the Hospital Universitari i Politècnic La Fe of Valencia.
The project is coordinated by the Norwegian company Made for Movement Group. Besides Biomechanics Institute, other members of the consortium are Innovatsiooni Eesti Instituut (Estonia), INNORA ROBOTICS (Greece), Newtrim and MCT (UK), ENIX (France), Motus (Italy) and MOBILE ROBOTICS SWEDEN (Sweden).
Stroke (cerebrovascular accident) is the most common cause of adult disability in Europe. Roughly 75% of victims survive, but about half of these lose the ability to live independently in their own home. As strokes often result in long term disability rather than death, the rehabilitation and hospitalisation represent a major economic burden for the EU of about €34 Bn annually. Currently, the annual incidence is approximately 2 per 1,000 inhabitants in the EU, and the number is predicted to double over the next 50 years due to the aging of the population.
Botox may help stroke patients
Injecting botox into the arm muscles of stroke survivors, with severe spasticity, changes electrical activity in the brain and may assist with longer-term recovery, according to new research.
Researchers at NeuRA (Neuroscience Research Australia) monitored nerve activity in the arms and brains of stroke survivors before and after botulinum toxin (botox) injections in rigid and stiff muscles in the arm.
They found that botox indeed improved arm muscles, but also altered brain activity in the cortex – the brain region responsible for movement, memory, learning and thinking.
“Botulinum toxin is used to treat a range of muscular and neurological conditions and our data shows that this treatment results in electrical and functional changes within the brain itself”, says Dr William Huynh, lead author of the study and a research neurologist at NeuRA.
“This effect of botox on the brain may arise because the toxin travels to the central nervous system directly, or because muscles treated with botox are sending different signals back to the brain”.
“Either way, we found that botox treatment in affected muscles not only improves muscle disorders in stroke patients, but also normalises electrical activity in the brain, particularly in the half of the brain not damaged by stroke”.
“Restoring normal activity in the unaffected side of the brain is particularly important because we suspect that abnormal information sent from affected muscles to the brain may be disrupting patients’ long-term recovery”, Dr Huynh concluded.
This paper is published in the journal Muscle and Nerve.