Tag: stroke

Walking Faster Helps Stroke Survivors to Dual-task

Photo by bennett tobias on Unsplash

Training stroke survivors to walk faster during recovery can help improve their ability to perform a task at the same time, known as dual-task walking.

Stroke survivors often struggle to walk and perform cognitive tasks at the same time, for example, walking and holding a conversation, or planning what to do next. To effectively walk in the community, cognitive effort is needed to navigate safely and deal with distractions. Many people are unable to regain this ability after a stroke.

Dual-task training ineffective

To improve the ability to walk and think at the same time, rehabilitation approaches have focused on practising walking and at the same performing a task needing cognition, known as dual-task training. Previous research led by Oxford Brookes University and the University of Oxford found that this training did not improve people’s ability to dual-task walk any more than just walking training.

Researchers reasoned that why people struggle with dual-task walking after a stroke may instead be linked to their walking automaticity – the pattern our brains run which means not having to think about walking. This pattern is linked to the cyclic pattern of walking whereby one step ‘signals’ the next step to follow. When walking very slowly, this pattern could be disrupted so that walking is more like independent steps, rather than a cycle.

Faster walkers improved dual-task walking

The new research re-examined the data to compare how slower walkers and faster walkers responded to dual-task training.

“When we compared slower walkers and people who walked at a faster pace – still slower, but closer to walking speeds we expect to see in people who have not had a stroke – both increased their walking speeds after the training,” said Dr Johnny Collett, Senior Clinical Research Fellow in the Centre for Movement, Occupational and Rehabilitation Sciences at Oxford Brookes University.

“However, those who could walk faster at the beginning of the training also improved their ability to walk and think at the same time.”

Advanced brain imaging tracked responses to training

As part of the study, researchers tracked how people’s brains responded to the training using advanced brain imaging. Changes found in the brain supported the findings that stroke survivors who walked slower, had a less automatic control of  walking. Those who walked at a faster pace had changes in the brain consistent with adaptations needed for controlling gait in more complex environments.

“These findings show that, for those who walk slowly, initially focusing on improving walking speed may increase their capacity to improve dual-task walking,” added Dr Collett. “Greater consideration of walking automaticity may help to better tailor intervention and direct a staged approach of increasing complexity to make people better able to walk in the community.”

Importance for rehabilitation

Dr Rubina Ahmed, Director for Research and Policy at the Stroke Association said: “Stroke strikes every 5 minutes and has devastating physical and mental impacts. Whilst four out of five stroke survivors recover the ability to walk, most find it hard outside of hospital which has a big impact on their well-being and independence. By funding this research our charity has helped to highlight that training focused on walking speeds could be an important part of rehabilitation for some stroke survivors’ recoveries. Research like this is key to finding new treatments and improving stroke care, so that stroke survivors can regain the mobility and independence they need to rebuild their lives.”

Source: Oxford Brookes University

Journal reference: Collett, J., et al. (2021) Dual-task walking and automaticity after Stroke: Insights from a secondary analysis and imaging sub-study of a randomised controlled trial. Clinical Rehabilitation. doi.org/10.1177/02692155211017360.

Using a Gaming Console can Improve Stroke Patient Rehabilitation

Photo by Tima Miroshnichenko from Pexels

A study by the Faculty of Physiotherapy of the University of Valencia (UV) has shown that a physiotherapy programme using the Nintendo Wii console improves the functionality, balance and daily activities of patients who have suffered a cerebrovascular accident or stroke.
Wii research group

The study found that when the Wii is added to conventional physiotherapy techniques, the benefits are significant in stroke patients. Besides improvements in functionality and balance, the physiotherapy programme using the Wii also helps to improve daily activities.

The use of game consoles in medicine has focused on aspects such as helping build motor skills and pain management with virtual reality immersion. They are relatively cheap and available, and simple to use. One study looked at using a Microsoft Xbox to help rehabilitation of patients with Parkinson’s disease.

Previous research had already shown that the Wii can help normal treatments in restoring functionality in some chronic diseases. However, until now, there was little evidence of its use in people who had suffered strokes. “Before conducting the study we realised that not much research had been done with stroke patients, so we wanted to know if console games could promote mobility, balance and the day-to-day life of people with this pathology”, explained Elena Marqués, one of the researchers and professor of Physiotherapy at the UV.

The study recruited 29 participants into two groups, one using the Wii and conventional techniques, and the other performing traditional physiotherapy exercises. “The sample is relatively large considering it is comprised by patients who suffered strokes, as because they have many physical limitations, their treatment is usually much more individualised than that of other pathologies”, said the author.

These video games allow therapists to design rehabilitation programs that improve the principles of brain plasticity. An additional advantage is that the console provides real-time feedback on performance and progress, which can increase patient motivation, fun, and treatment adherence. “It should be taken into account that some patients have not performed any exercise before, regardless of the pathology they have, so being presented as a game can be an incentive”, said Prof Marqués.

She pointed out that other benefits include the Wii being easy to use, relatively affordable and, most importantly, can be used individually and at home, without needing to visit a rehab centre. This is particularly useful with COVID lockdowns.

This is one of the first studies using consoles as a therapeutic option, but it can be extended to patients with other pathologies, “because it allows you to work the balance with the console table, both in the chronic phase and in the subacute phase”, said Marqués.

Strengthening mirror neurons

Many Wii games use the remote control, but the console also offers a balance table that detects weight transfer by reflecting it in an avatar on the screen, letting the patient observe his/her own movements and generate positive feedback.

Thus, when the person observes his/her movements, the plasticity changes that depend on the use of sensory areas belonging to the mirror neuron system are strengthened. This exemplifies, among other factors, the improvements the Wii can provide in such patients. This feedback could result in a strengthening of the learning mechanisms of different motor and sensory activities and ultimately improving quality of life.

Source: Asociación RUVID

Boy’s Brain Rewires After Stroke as a Newborn

Photo by cottonbro from Pexels

Researchers have reported the case of a boy whose brain was able to rewire after a severe stroke that damaged much of his brain.

In the seventh grade, 13-year old Daniel Carr amazed his baseball coach with his ability to throw with his left hand, saying that it was the fastest he’d ever seen. However, he was unable to properly catch with his right hand.

Hearing this from the coach, Kellie Carr, Daniel’s mother, realised that his son had a number of quirks, such as favouring his left side when he was an infant, and his left-handedness emerged well before the normal age of two or three. However, she was unable to get any explanation for this until she met Nico Dosenbach, MD, PhD, who informed her that her son had had a stroke when he was a newborn.

MRI scans revealed large, bilateral voids in Daniel’s brain, but incredibly, he had no cognitive, behavioural or motor problems other than a lack of strength and dexterity in his right arm.
“The extent of Daniel’s injuries may be on the edge of what’s compatible with life,” Dosenbach said.

Dainel’s remarkable recovery can be explained by his young age at the time the stroke.

“The brain can compensate more quickly and completely for strokes sustained in early childhood,” he said. “By contrast, large strokes in adults often cause death or severe functional impairment with little chance of recovery. However, the mechanics behind this are only beginning to be understood.”

More MRI scans were done on Daniel’s brain to determine its structure and pathology. Dosenbach and Laumann conducted high-resolution functional MRI scans to understand how Daniel’s brain had reorganised itself.
With his mother’s consent, Daniel was further tested over a period of six years, including batteries of neurological tests, and more scans done. Timothy Laumann, MD, PhD, now a fourth-year psychiatry resident at Barnes-Jewish Hospital, had the expertise to analyse the data.

Looking at his medical records, the physician-scientists noted that he had an infection as a newborn, and was hospitalised with an IV drip. However, none of the physicians had suspected a stroke, which happens to one in every 4000 newborns. Daniel was sent home after a week, the doctors having suspected a viral infection.

“The risk of having a pediatric stroke greatly increases with a medical problem, especially an infection during the newborn period,” Dosenbach said. “However, usually there are more obvious signs that a stroke occurred. I can understand how no one suspected it.”

The researchers compared the images of Daniel’s brain to others of young adults, as well as Dosenbach’s own brain, which he had imaged and studied extensively.

“Part of Daniel’s brain structure is gone,” Laumann explained, referring to their analysis of the MRI data. “He’s missing almost a quarter of his cortex.”

The dead tissue was replaced by pockets of cerebrospinal fluid, which acts as a shock absorber, as well as delivering nutrients and removing waste. The surviving neurons formed interconnected islands that restored cognitive and motor functions, and neighbourhoods of healthy tissue were again reconnected.

“Our findings illustrate the brain’s tenacity at reorganizing and recovering functions damaged by a massive stroke affecting both sides of his brain,” Dosenbach said. “Future studies of functional remapping relative to tissue loss may provide additional insights. Our results raise the possibility that variability in outcomes may depend on specific features unique to an individual’s brain.”

Despite the extensive damage, Daniel completed tertiary education and now works as a diesel mechanic.

“His stroke still shocks me,” Kellie Carr said. “How could I have not known? But looking back, maybe it was better that way. I might have babied Daniel and been afraid to let him be a regular kid. Maybe the best thing for him was living normally.”

Daniel agreed: “I think about my right hand daily because I have to constantly think five steps ahead to figure out how to compensate for not being able to use it properly, like I did with the baseball glove. But the last thing I want is for people to act like something is wrong with me. I’m fine.”

Source: Medical Xpress

Journal information: Timothy O Laumann et al. Brain network reorganisation in an adolescent after bilateral perinatal strokes, The Lancet Neurology (2021). DOI: 10.1016/S1474-4422(21)00062-4

Central Retinal Artery Occlusion Needs to be Treated as A Stroke

The American Heart Association published a new scientific statement, “Management of Central Retinal Artery Occlusion,” which laid out the best methods to treat what is effectively a small stroke in the eye.

A central retinal artery occlusion (CRAO) is a rare (1 in 100 000 people) form of acute ischaemic stroke arising from a blockage of blood flow to the main artery of the eye. It causes painless, immediate vision loss in the impacted eye from which less than 20% of people will recover from.

“Central retinal artery occlusion is a cardiovascular problem disguised as an eye problem. It is less common than stroke affecting the brain but is a critical sign of ill health and requires immediate medical attention,” said the chair of the statement writing committee Brian C Mac Grory, MBBCh, BAO, MRCP, an assistant professor of neurology and staff neurologist at the Duke Comprehensive Stroke Center at Duke University School of Medicine. “Unfortunately, a CRAO is a warning sign of other vascular issues, so ongoing follow-up is critical to prevent a future stroke or heart attack.”

In a comprehensive review of the literature, committee members from a variety of specialties summarised the state of the science in this condition. They noted that a lack of clinical trials results in physicians not recognising the problem, including that it is a type of stroke, resulting in inaction and differing methods of diagnosis and treatment.

“We know acute CRAO is a medical emergency requiring early recognition and triage to emergency medical treatment,” said Dr Mac Grory. “There is a narrow time window for effective treatment of CRAO and a high rate of serious related illness. So, if a person is diagnosed in a doctor’s office or another outpatient clinic, they should be immediately sent to a hospital emergency department for further evaluation and treatment.”

CRAOs can be caused by problems with carotid arteries, the blood vessels in the neck, but there is also evidence CRAOs could be caused by heart problems such as atrial fibrillation.

CRAO risk factors include age and the presence of cardiovascular risk factors such as type 2 diabetes, smoking, and obesity. 

Currently, the literature suggests that intravenous tissue plasminogen activator (tPA) treatment, a “clot buster” also used for brain strokes, could be effective. However, to be effective and safe tPA must be administered within 4.5 hours of the onset of symptoms

Hyperbaric oxygen and intra-arterial alteplase, were also noted as showing potential but requiring further study. Hyperbaric oxygen can result in an improvement if done within 24 hours of the CRAO event. Other possible treatments needing further research icnclude breaking up clots with novel thrombolytics and using novel neuroprotectants (substances capable of preserving brain function and structure) in concert with other treatments to restore blood flow in the blocked artery.

Since there is potential for future strokes or even heart attacks, patients should undergo screening and treatment of vascular risk factors as a matter of urgency. CRAOs are complex to treat and manage, requiring the joint effort of a team of specialists.

Secondary prevention (including monitoring for complications) must be a collaborative effort between neurologists, ophthalmologists, cardiologists and primary care clinicians. Risk factor modification includes lifestyle and pharmacological interventions.

Source: News-Medical.Net

Journal information: Grory, B. M., et al. (2021) Management of Central Retinal Artery Occlusion: A Scientific Statement From the American Heart Association. Stroke. doi.org/10.1161/STR.0000000000000366.

New Study Has Good and Bad News on TIAs

There is both good and news on transient ischaemic attacks (TIAs) from a more than six-decade long study: TIAs are indeed harbingers of strokes, but also the incidence of post-TIA strokes has been falling over the decades.

A TIA is defined as a passing episode of neurologic dysfunction due to the focal brain, spinal cord, or retinal ischaemia, without acute infarction or tissue injury. The results were derived from the Framingham Heart Study had 14 059 participants and ran for over six decades, allowing for a more-complete picture of strokes that happen after a TIA. Of the participants, 435 had a TIA; these were compared against a second group of 2175 participants who did not have a TIA.

Even after accounting for other risk factors such as hypertension or diabetes, people who had experienced a TIA had a 4.5 to five times greater chance of a stroke. Study lead author Vasileios-Arsenios Lioutas, MD, said that the results show a need for intensive follow-up of TIA : “According to our findings, people continue to have a high risk of stroke for a sustained time after they’ve had a TIA. Therefore, one shouldn’t think that the high-risk period is just in the first 90 days after the attack and then one can relax. It seems these patients should be followed closely over time, keeping in mind that they are at risk for stroke and paying close attention to controlling their cardiovascular risk factors.”

The 66 years of study data was broken into three epochs. One- and five-year risks of post-TIA stroke in the 2000-2017 epoch were 7.6% and 16.1%, compared to 23.9% and 35.5% during the earliest epoch, from 1948 to 1985.

Sudha Seshadri, MD, professor of neurology at The University of Texas Health Science Center at San Antonio, said: “We examined 66 years of follow-up from Framingham participants, which allowed us to study trends over time. We can see that starting in the very early years of the Framingham study, the 1950s, moving on to the most recent times, the risk of subsequent stroke went down a lot.”

Source: News-Medical.Net

Journal information: Lioutas, V-A., et al. (2021) Incidence of Transient Ischemic Attack and Association With Long-term Risk of Stroke. JAMA.doi.org/10.1001/jama.2020.25071.