Month: April 2024

Categories : IT in HealthcareTags :

When it Comes to Healthcare, AI Still Needs Human Supervision

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Photo by Tara Winstead on Pexels

State-of-the-art artificial intelligence systems known as large language models (LLMs) are poor medical coders, according to researchers at the Icahn School of Medicine at Mount Sinai. Their study, published in NEJM AI, emphasises the necessity for refinement and validation of these technologies before considering clinical implementation.

The study extracted a list of more than 27 000 unique diagnosis and procedure codes from 12 months of routine care in the Mount Sinai Health System, while excluding identifiable patient data. Using the description for each code, the researchers prompted models from OpenAI, Google, and Meta to output the most accurate medical codes. The generated codes were compared with the original codes and errors were analysed for any patterns.

The investigators reported that all of the studied large language models, including GPT-4, GPT-3.5, Gemini-pro, and Llama-2-70b, showed limited accuracy (below 50%) in reproducing the original medical codes, highlighting a significant gap in their usefulness for medical coding. GPT-4 demonstrated the best performance, with the highest exact match rates for ICD-9-CM (45.9%), ICD-10-CM (33.9%), and CPT codes (49.8%).

GPT-4 also produced the highest proportion of incorrectly generated codes that still conveyed the correct meaning. For example, when given the ICD-9-CM description “nodular prostate without urinary obstruction,” GPT-4 generated a code for “nodular prostate,” showcasing its comparatively nuanced understanding of medical terminology. However, even considering these technically correct codes, an unacceptably large number of errors remained.

The next best-performing model, GPT-3.5, had the greatest tendency toward being vague. It had the highest proportion of incorrectly generated codes that were accurate but more general in nature compared to the precise codes. In this case, when provided with the ICD-9-CM description “unspecified adverse effect of anesthesia,” GPT-3.5 generated a code for “other specified adverse effects, not elsewhere classified.”

“Our findings underscore the critical need for rigorous evaluation and refinement before deploying AI technologies in sensitive operational areas like medical coding,” says study corresponding author Ali Soroush, MD, MS, Assistant Professor of Data-Driven and Digital Medicine (D3M), and Medicine (Gastroenterology), at Icahn Mount Sinai. “While AI holds great potential, it must be approached with caution and ongoing development to ensure its reliability and efficacy in health care.”

Source: The Mount Sinai Hospital / Mount Sinai School of Medicine

Categories : Gastrointestinal Pain ManagementTags :

Acid-lowering Meds Linked to Greater Risk of Migraines

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Photo by Usman Yousaf on Unsplash

People who take acid-reducing drugs may have a higher risk of migraine and other severe headache than people who do not take these medications, a new study has shown. The acid-reducing drugs include proton pump inhibitors such as omeprazole and esomeprazole, histamine H2-receptor antagonists, or H2 blockers, such as cimetidine and famotidine, and antacid supplements.

The study, study published in Neurology®Clinical Practice, an official journal of the American Academy of Neurology, does not prove causation; only an association.

In acid reflux, stomach acid flows into the oesophagus, usually after a meal or when lying down, causing heartburn and ulcers. People with frequent acid reflux may develop gastroesophageal reflux disease, or GORD, which can lead to cancer of the oesophagus.

“Given the wide usage of acid-reducing drugs and these potential implications with migraine, these results warrant further investigation,” said study author Margaret Slavin, PhD, RDN, of the University of Maryland in College Park. “These drugs are often considered to be overprescribed, and new research has shown other risks tied to long-term use of proton pump inhibitors, such as an increased risk of dementia.”

For the study, researchers looked at data on 11,818 people who provided information on use of acid-reducing drugs and whether they had migraine or severe headache in the past three months.

A total of 25% of participants taking proton pump inhibitors had migraine or severe headache, compared to 19% of those who were not taking the drugs. A total of 25% of those taking H2 blockers had severe headache, compared to 20% of those who were not taking those drugs. And 22% of those taking antacid supplements had severe headache, compared to 20% of those not taking antacids.

When researchers adjusted for other factors that could affect the risk of migraine, such as age, sex and use of caffeine and alcohol, they found that people taking proton pump inhibitors were 70% more likely to have migraine than people not taking proton pump inhibitors. Those taking H2 blockers were 40% more likely and those taking antacid supplements were 30% more likely.

“It’s important to note that many people do need acid-reducing medications to manage acid reflux or other conditions, and people with migraine or severe headache who are taking these drugs or supplements should talk with their doctors about whether they should continue,” Slavin said.

Slavin noted that the study looked only at prescription drugs. Some of the drugs became available for over-the-counter use at non-prescription strength during the study period, but use of these over-the-counter drugs was not included in this study.

Other studies have shown that people with gastrointestinal conditions may be more likely to have migraine, but Slavin said that relationship is not likely to fully explain the tie between acid-reducing drugs and migraine found in the study.

A limitation of the study is that a small number of people were taking the drugs, especially the H2 blockers.

Source: American Academy of Neurology

Categories : Mental HealthTags :

In Anorexia Nervosa, What Triggers Wilful Starvation?

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Photo from Freepik.

A new study led by investigators at Beth Israel Deaconess Medical Center (BIDMC) suggests that female mice that are prone to anxiety may prefer and actively seek out a starvation-like state in response to repeated exposure to stress. The findings, published in the journal Neuron, may provide a useful experimental model for investigating the neural mechanisms underlying anorexia nervosa – particularly its onset.

“While anorexia nervosa has been documented for over 300 years, its underlying causes remain unknown,” said first author Hakan Kucukdereli, PhD, of the division of Endocrinology, Diabetes and Metabolism in the Department of Medicine at BIDMC.

“Current animal models fail to capture a key hallmark of the disorder – wilful starvation. Thus, there has been the pressing need for a pre-clinical mouse model that captures the intentional seeking of a starvation state.”

In healthy individuals, the state of hunger (or caloric deficit) is a mildly uncomfortable state that drives food-seeking behavior. In the lab, Kucukdereli, senior author Mark L. Andermann, and colleagues knew that precise stimulation of a few thousand neurons known as AgRP neurons will cause even a well-fed mouse to seek out another meal.

They also knew that actual food restriction – which activates these AgRP neurons – and the artificial starvation state caused by stimulating these neurons can tamp down anxiety, thereby promoting food-seeking. (Imagine a hungry mouse in your kitchen that needs to be bold enough to hunt for food, even when your cat is around.)

Based on prior associations between stress, anxiety, and anorexia nervosa, Andermann and colleagues hypothesised that exposure to high levels of stress may actually trigger individuals to wilfully seek starvation as a means of reducing anxiety. The scientists trained 15 male and 17 female mice to run through a virtual reality corridor where they could choose to stop in one room associated with stimulation of their AgRP neurons or a second room associated with no stimulation.

In the absences of stress, male mice avoided AgRP stimulation; however, only a minority of female mice exhibited a strong aversion to it. Subsequent to repeated stress, however, many of these same mice behaved very differently. When the researchers exposed the mice to a five-minute period of unpredictable tail shocks, the males became, on average, less averse to AgRP stimulation. Meanwhile, female mice tended to preferAgRP stimulation following stress.

“Strikingly, a subset of females, but not males, began to vigorously seek this starvation-like state following stress,” said Andermann, who is also a professor of Medicine and Neurobiology at Harvard Medical School. “Surprisingly, individuals’ baseline levels of anxiety-like behavior measured weeks before the experiment could predict which females will develop a preference for this starvation-like state.”

Using machine learning to analyse the animals’ facial expressions, the researchers found that, after exposure to stress, female mice with strong preference for AgRP stimulation also showed facial expressions that directly correlated with their behaviour, potentially reflecting relief associated with a reduction in anxiety.

“Future research can link these moment-to-moment changes in facial expressions with ongoing activity of many neurons in brain regions that track physiological states or that process negative emotions,” Kucukdereli said. “Our approach lays the groundwork for future work that will identify the neural circuits that underlie the voluntary maintenance of long-term starvation in individuals with anorexia nervosa.”

Source: Beth Israel Deaconess Medical Center

Categories : Ageing Mental HealthTags :

Trial with Warning Letters on Antipsychotic’s Risks Safely Cut Prescribing

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Photo by Towfiqu Barbhuiya on Unsplash

Warning letters from Medicare can safely cut prescribing of a powerful but risky antipsychotic, according to a new study published in JAMA Network Open. Researchers used data from Medicare, the U.S. public health insurance system for over 65s, to study the effects of the letters on hundreds of thousands of older adults with dementia. The study, by Columbia University Mailman School of Public Health, found a significant and lasting reduction in prescribing but no signs of adverse effects on patient health.

“Our study shows that low-cost letter interventions can safely reduce antipsychotic prescribing to patients with dementia,” said Adam Sacarny, PhD, assistant professor of Health Policy and Management at Columbia Mailman School. The work was conducted with researchers at the London School of Economics, Harvard T.H. Chan School of Public Health and Johns Hopkins University.

The researchers evaluated a large trial in which Medicare sent warning letters to high prescribers of quetiapine, the most popular antipsychotic in the U.S. Antipsychotics are frequently prescribed to people with dementia, but can cause numerous harms in this group. Researchers therefore studied the hundreds of thousands of older adults with dementia who were treated by the prescribers in the trial. Most previous studies on reducing prescribing in dementia care consisted of small trials or observational analyses, with limited evidence from large-scale randomised studies.

The results were striking. “People with dementia living in nursing homes and in the community were prescribed less and we did not detect negative health impacts for these groups,” said Michelle Harnisch, research student at the London School of Economics and first author of the study.

The findings are important because antipsychotics, such as quetiapine, are often used in dementia care to address behavioural symptoms. About 1 in 7 nursing home residents receives an antipsychotic every quarter. However, the drugs have a number of well-known risks. These include weight gain, cognitive decline, falls, and death. In turn, physician specialty societies, government regulators, and policymakers have aimed to reduce prescribing of these medications to people with dementia.

To test whether the warning letters reduced prescribing safely, the researchers used administrative data from Medicare to link the 5055 physicians in the original trial to the Medicare records of their patients with dementia. They ultimately analysed 84 881 patients in nursing homes and 261,288 patients living in the community.

The intervention reduced quetiapine use among nursing home patients by 7% and community-dwelling patients by 15%. The researchers did not find adverse effects across numerous health outcomes, including cognitive function, behavioural symptoms, depression, or metabolic outcomes like diabetes. There were signs of improved mental health outcomes, and the risk of death for patients living in the community fell slightly.

This research follows up on the original evaluation of the warning letters. In that study, members of the same research team also showed that the letters reduced prescribing. However, they focused on a considerably smaller sample of patients and studied a limited set of health outcomes. In contrast, the new research evaluates a number of key health indicators for dementia care and substantially expands the patient sample with a focus on dementia.

“These results show that this intervention and others like it could be leveraged to make prescribing safer and improve dementia care” noted Sacarny. “Similar interventions could also be adapted to other contexts to promote high-quality care.”

Source: Columbia University’s Mailman School of Public Health

Categories : NeurologyTags :

How Spinal Cords can ‘Learn’ without Brain Involvement

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In this study, spinal cords that associated limb position with an unpleasant experience learned to reposition the limb after only 10 minutes, and retained a memory the next day. Spinal cords that received random unpleasantness did not learn. Credit: RIKEN

Researchers in Japan have discovered the neural circuitry in the spinal cord that allows brain-independent motor learning. This study by Aya Takeoka at the RIKEN Center for Brain Science and colleagues found two critical groups of spinal cord neurons, one necessary for new adaptive learning, and another for recalling adaptations once they have been learned. The findings, published in Science, could help scientists develop ways to assist motor recovery after spinal cord injury.

It has been long been known that motor output from the spinal cord can be adjusted through practice even without a brain. This has been shown most dramatically in headless insects, whose legs can still be trained to avoid external cues. Until now, no one has figured out exactly how this is possible, and without this understanding, the phenomenon is not much more than a quirky fact. As Takeoka explains, “Gaining insights into the underlying mechanism is essential if we want to understand the foundations of movement automaticity in healthy people and use this knowledge to improve recovery after spinal cord injury.”

Before jumping into the neural circuitry, the researchers first developed an experimental setup that allowed them to study mouse spinal cord adaptation, both learning and recall, without input from the brain. Each test had an experimental mouse and a control mouse whose hindlegs dangled freely. If the experimental mouse’s hindleg drooped down too much it was electrically stimulated, emulating something a mouse would want to avoid. The control mouse received the same stimulation at the same time, but not linked to its own hindleg position.

After just 10 minutes, they observed motor learning only in the experimental mice; their legs remained high up, avoiding any electrical stimulation. This result showed that the spinal cord can associate an unpleasant feeling with leg position and adapt its motor output so that the leg avoids the unpleasant feeling, all without any need for a brain. Twenty-four hours later, they repeated the 10-minute test but reversed the experimental and control mice. The original experimental mice still kept their legs up, indicating that the spinal cord retained a memory of the past experience, which interfered with new learning.

Having thus established both immediate learning, as well as memory, in the spinal cord, the team then set out to examine the neural circuitry that makes both possible. They used six types of transgenic mice, each with a different set of spinal neurons disabled, and tested them for motor learning and learning reversal. They found that mice hindlimbs did not adapt to avoid the electrical shocks after neurons toward the top of the spinal cord were disabled, particularly those that express the gene Ptf1a.

When they examined the mice during learning reversal, they found that silencing the Ptf1a-expressing neurons had no effect. Instead, a group of neurons in the ventral part of the spinal cord that express the En1 gene was critical. When these neurons were silenced the day after learning avoidance, the spinal cords acted as if they had never learned anything. The researchers also assessed memory recall on the second day by repeating the initial learning conditions. They found that in wildtype mice, hindlimbs stabilised to reach the avoidance position faster than they did on the first day, indicating recall. Exciting the En1 neurons during recall increased this speed by 80%, indicating enhanced motor recall.

“Not only do these results challenge the prevailing notion that motor learning and memory are solely confined to brain circuits,” says Takeoka, “but we showed that we could manipulate spinal cord motor recall, which has implications for therapies designed to improve recovery after spinal cord damage.”

Source: RIKEN

Categories : Injury & Trauma Metabolic DisordersTags :

Shoe Technology Reduces Risk of Diabetic Foot Ulcers

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Credit: Pixabay CC0

Researchers have developed a new shoe insole technology that helps reduce the risk of diabetic foot ulcers, which can lead to hospitalisation and leg, foot or toe amputations. They describe the technology in The International Journal of Lower Extremity Wounds.

“The goal of this innovative insole technology is to mitigate the risk of diabetic foot ulcers by addressing one of their most significant causes: skin and soft tissue breakdown due to repetitive stress on the foot during walking,” said Muthu B.J. Wijesundara, principal research scientist at The University of Texas at Arlington Research Institute (UTARI).

Diabetes can damage the small blood vessels that supply blood to the nerves, leading to poor circulation and foot sores, also called ulcers. About one-third of people with diabetes develop foot ulcers during their lifetime. Those who have foot ulcers often die at younger ages than those without ulcers.

“Although many shoe insoles have been created over the years to try to alleviate the problem of foot ulcers, studies have shown that their success in preventing them is marginal,” Wijesundara said. “We took the research a step further by creating a pressure-alternating shoe insole that works by cyclically relieving pressure from different areas of the foot, thereby providing periods of rest to the soft tissues and improving blood flow. This approach aims to maintain the health of the skin and tissues, thereby reducing the risk of diabetic foot ulcers.”

In an article in the peer-reviewed International Journal of Lower Extremity Wounds, Wijesundara and UTA colleagues Veysel Erel, Aida Nasirian and Yixin Gu, along with Larry Lavery of UT Southwestern Medical Center, described their innovative insole technology. After this successful pilot project, the next step for the research team will be refining the technology to make it more accessible for users with varying weights and shoe sizes.

“Considering the impact of foot ulcers, it’s exciting that we may be able to make a real difference in the lives of so many people,” Wijesundara said.

Source: University of Texas at Arlington

Categories : AgeingTags :

New Study Explains Why we Move More Slowly with Age

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It’s one of the inescapable realities of aging: The older we get, the slower we tend to move – whether we’re walking around the block or just reaching for the remote control. A new study led by CU Boulder engineers helps explain why.

The research is one of the first studies to experimentally tease apart the competing reasons why people over age 65 might not be as quick on their feet as they used to be. The group reported that older adults may move slower, at least in part, because it costs them more energy than younger people – perhaps not too shocking for anyone who’s woken up tired the morning after an active day.

The findings could one day give doctors new tools for diagnosing a range of illnesses, including Parkinson’s disease, multiple sclerosis and even depression and schizophrenia, said study co-author Alaa Ahmed. 

“Why we move the way we do, from eye movements to reaching, walking and talking, is a window into aging and Parkinson’s,” said Ahmed, professor in the Paul M. Rady Department of Mechanical Engineering. “We’re trying to understand the neural basis of that.”

She and her colleagues published their findings this month in the journal JNeurosci.

For the study, the group asked subjects age 18 to 35 and 66 to 87 to complete a deceptively simple task: to reach for a target on a screen, akin to playing a video game on a Nintendo Wii. By analysing patterns of these reaches, the researchers discovered that older adults seemed to modify their motions under certain circumstances to conserve their more limited supplies of energy. 

“All of us, whether young or old, are inherently driven to get the most reward out of our environment while minimising the amount of effort to do so,” said Erik Summerside, a co-lead author of the new study who earned his doctorate in integrative physiology from CU Boulder in 2018.

Using engineering to understand the brain

Ahmed added that researchers have long known that older adults tend to be slower because their movements are less stable and accurate. But other factors could also play a role in this fundamental part of growing up.

According to one hypothesis, the muscles in older adults may work less efficiently, meaning that they burn more calories while completing the same tasks as younger adults – like running a marathon or getting up to grab a soda from the refrigerator.

Alternatively, aging might also alter the reward circuitry in the human brain. Ahmed explained that as people age, their bodies produce less dopamine, a brain chemical responsible for giving you a sense of satisfaction after a job well done. If you don’t feel that reward as strongly, the thinking goes, you may be less likely to move to get it. People with Parkinson’s disease experience an even sharper decline in dopamine production.

In the study, the researchers asked more than 80 people to sit down and grab the handle of a robotic arm, which, in turn, operated the cursor on a computer screen. The subjects reached forward, moving the cursor toward a target. If they succeeded, they received a reward – not a big one, but still enough to make their brains happy.

“Sometimes, the targets exploded, and they would get point rewards,” Ahmed said. “It would also make a ‘bing bing’ sound.”

Moving slower but smarter

That’s when a contrast between the two groups of people began to emerge.

Both the 18 to 35-year-olds and 66 to 87-year-olds arrived at their targets sooner when they knew they would hear that ‘bing bing’ – roughly 4% to 5% sooner over trials without the reward. But they also achieved that goal in different ways.

The younger adults, by and large, moved their arms faster toward the reward. The older adults, in contrast, mainly improved their reaction times, beginning their reaches about 17 milliseconds sooner on average.

When the team added an 8-pound (3.6kg) weight to the robotic arm for the younger subjects, those differences vanished.

“The brain seems to be able to detect very small changes in how much energy the body is using and adjusts our movements accordingly,” said Robert Courter, a co-lead author of the study who earned his doctorate in integrative physiology from CU Boulder in 2023. “Even when moving with just a few extra pounds, reacting quicker became the energetically cheaper option to get to the reward, so the young adults imitated the older adults and did just that.”

The research seems to paint a clear picture, Ahmed said. Both the younger and older adults didn’t seem to have trouble perceiving rewards, even small ones. But their brains slowed down their movements under tiring circumstances.

“Putting it all together, our results suggest that the effort costs of reaching seem to be determining what’s slowing the movement of older adults,” Ahmed said.

The experiment can’t completely rule out the brain’s reward centres as a culprit behind why we slow down when we age. But, Ahmed noted, if scientists can tease out where and how these changes emerge from the body, they may be able to develop treatments to reduce the toll of aging and disease.

Source: University of Colorado Boulder

Categories : Diet and NutritionTags :

Social Media can Influence Young People to Eat More Healthily

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Photo by Alex Haney

Researchers from Aston University have found that people following healthy eating accounts on social media for as little as two weeks ate more fruit and vegetables and less junk food.

Previous research has shown that positive social norms about fruit and vegetables increases individuals’ consumption. The research team sought to investigate whether positive representation of healthier food on social media would have the same effect. The research was led by Dr Lily Hawkins, whose PhD study it was, supervised by Dr Jason Thomas and Professor Claire Farrow in the School of Psychology.

The researchers recruited 52 volunteers, all social media users, with a mean age of 22, and split them into two groups. Volunteers in the first group, known as the intervention group, were asked to follow healthy eating Instagram accounts in addition to their usual accounts. Volunteers in the second group, known as the control group, were asked to follow interior design accounts. The experiment lasted two weeks, and the volunteers recorded what they ate and drank during the time period.

Overall, participants following the healthy eating accounts ate an extra 1.4 portions of fruit and vegetables per day and 0.8 fewer energy dense items, such as high-calorie snacks and sugar-sweetened drinks, per day. This is a substantial improvement compared to previous educational and social media-based interventions attempting to improve diets.

Dr Thomas and the team believe affiliation is a key component of the change in eating behaviour. For example, the effect was more pronounced amongst participants who felt affiliated with other Instagram users.

The 2018 NHS Health Survey for England study showed that only 28% of the UK population consumed the recommended five portions of fruit and vegetables per day. Low consumption of such food is linked to heart disease, cancer and stroke, so identifying ways to encourage higher consumption is vital. Exposing people to positive social norms, using posters in canteens encouraging vegetable consumption, or in bars to discourage dangerous levels of drinking, have been shown to work. Social media is so prevalent now that the researchers believe it could be an ideal way to spread positive social norms around high fruit and vegetable consumption, particularly amongst younger people.

Dr Hawkins, who is now at the University of Exeter, said: “Our previous research has demonstrated that social norms on social media may nudge food consumption, but this pilot demonstrates that this translates to the real world. Of course, we would like to now understand whether this can be replicated in a larger, community sample.”

Source: Aston University

Categories : Cardiovascular DiseaseTags :

Study Finds Positive Effects with Anaesthetic Drug after Cardiac Arrest

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Photo by Mat Napo o Unsplash

If a patient is successfully resuscitated after a cardiac arrest and circulation resumes, they are not out of the woods yet. A number of factors can influence whether and how they survive the trauma in the subsequent phase. But a multicentre study of 571 patients has shown that the administration of the anaesthetic midazolam has a positive effect.

In cases where the patient required anaesthesia after successful resuscitation, midazolam improved the chances of optimal oxygen saturation and CO2 levels in the blood. The risk of a renewed drop in blood pressure or a renewed circulatory arrest didn’t increase. “This specific group of patients who have been successfully resuscitated should definitely be included in the guidelines for pre-hospital anaesthesia. Midazolam has proven to have a particularly positive effect in this group,” concludes Dr Gerrit Jansen, lead author of the study, which was published in the journal Deutsches Ärzteblatt International.

In the event of a cardiac arrest, rapid intervention is essential: If first aiders carry out resuscitation measures in good time, the patient’s circulation can be restarted in the best-case scenario. “However, it’s often the case that the patient hasn’t yet regained consciousness,” explains Gerrit Jansen. In this phase, there are various factors that can affect the chances of survival and subsequent permanent limitations due to the circulatory arrest.

“Some patients display protective reflexes after resuscitation, such as coughing or defensive movements, which make the emergency responders’ work more difficult. They often have to perform extended airway management, for example by intubating the patient in the same way as during surgery. This frequently requires sedation or anaesthesia,” explains Jansen. Until now, there has been concern that anaesthetic drugs could have a negative impact on the circulatory system, which has only just been restored. According to the study, however, this is not the case.

Of the 571 people included in the study who survived a cardiac arrest and were admitted to hospital, 395 were sedated, 249 of them with midazolam. The chance that their blood oxygen saturation levels were in the optimal range following a cardiac arrest increased twofold when midazolam was administered. The chance that carbon dioxide was effectively exhaled increased by a factor of 1.6 with the drug. “Our statistical methods confirmed a correlation between these results and the administration of midazolam, without any indication of negative circulatory effects,” says Gerrit Jansen.

“The European guidelines of the European Resuscitation Council don’t yet set out any specific recommendations for possible anesthetic drugs,” explains Jansen. “The German guideline for pre-hospital anaesthesia for patients with cardiovascular risk doesn’t mention patients in cardiac arrest. We’ve therefore carried out pioneering research in this field, the results of which should be incorporated into the recommendations for the benefit of the patients.”

Source: Ruhr-University Bochum

Categories : Neurology Surgeries & ProceduresTags :

Spinal Surgeons can Now Monitor their Procedure’s Effects Mid-surgery

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Photo by Natanael Melchor on Unsplash

With technology developed at UC Riverside, scientists can, for the first time, make high resolution images of the human spinal cord during surgery. The advancement could help bring real relief to millions suffering chronic back pain.

The technology, known as fUSI or functional ultrasound imaging, not only enables clinicians to see the spinal cord, but also enables them to map the cord’s response to various treatments in real time. A paper published today in the journal Neuron details how fUSI worked for six people undergoing electrical stimulation for chronic back pain treatment.

“The fUSI scanner is freely mobile across various settings and eliminates the requirement for the extensive infrastructure associated with classical neuroimaging techniques, such as functional magnetic resonance imaging (fMRI),” said Vasileios Christopoulos, assistant professor of bioengineering at UCR who helped develop the technology. “Additionally, it offers ten times the sensitivity for detecting neuroactivation compared to fMRI.”

Until now, it has been difficult to evaluate whether a back pain treatment is working since patients are under general anaesthesia, unable provide verbal feedback on their pain levels during treatment. “With ultrasound, we can monitor blood flow changes in the spinal cord induced by the electrical stimulation. This can be an indication that the treatment is working,” Christopoulos said.

The spinal cord is an “unfriendly area” for traditional imaging techniques due to significant motion artifacts, such as heart pulsation and breathing. “These movements introduce unwanted noise into the signal, making the spinal cord an unfavorable target for traditional neuroimaging techniques,” Christopoulos said.

By contrast, fUSI is less sensitive to motion artifacts, using echoes from red blood cells in the area of interest to generate a clear image. “It’s like submarine sonar, which uses sound to navigate and detect objects underwater,” Christopoulos said. “Based on the strength and speed of the echo, they can learn a lot about the objects nearby.”

Christopoulos partnered with the USC Neurorestoration Center at Keck Hospital to test the technology on six patients with chronic low back pain. These patients were already scheduled for the last-ditch pain surgery, as no other treatments, including drugs, had helped to ease their suffering. For this surgery, clinicians stimulated the spinal cord with electrodes, in the hopes that the voltage would alleviate the patient’s discomfort and improve their quality of life.

“If you bump your hand, instinctively, you rub it. Rubbing increases blood flow, stimulates sensory nerves, and sends a signal to your brain that masks the pain,” Christopoulos said. “We believe spinal cord stimulation may work the same way, but we needed a way to view the activation of the spinal cord induced by the stimulation.”

The Neuron paper details how fUSI can detect blood flow changes at unprecedented levels of less than 1mm/s. For comparison, fMRI is only able to detect changes of 2cm/s.

“We have big arteries and smaller branches, the capillaries. They are extremely thin, penetrating your brain and spinal cord, and bringing oxygen places so they can survive,” Christopoulos said. “With fUSI, we can measure these tiny but critical changes in blood flow.”

Generally, this type of surgery has a 50% success rate, which Christopoulos hopes will be dramatically increased with improved monitoring of the blood flow changes. “We needed to know how fast the blood is flowing, how strong, and how long it takes for blood flow to get back to baseline after spinal stimulation. Now, we will have these answers,” Christopoulos said.

Moving forward, the researchers are also hoping to show that fUSI can help optimise treatments for patients who have lost bladder control due to spinal cord injury or age. “We may be able to modulate the spinal cord neurons to improve bladder control,” Christopoulos said.

“With less risk of damage than older methods, fUSI will enable more effective pain treatments that are optimised for individual patients,” Christopoulos said. “It is a very exciting development.”

Source: University of California Riverside