Investigators trained multiple artificial intelligence models to read images from echocardiograms, a type of ultrasound test that evaluates the structure and function of the heart. Their goal was to determine whether AI could use these images to calculate measurements like inflammation and scarring that are normally obtained through another, more costly test called cardiac magnetic resonance imaging (CMRI). By examining findings from 1453 patients who had undergone both tests, they found the AI models could not accomplish this task.
“As compared to echocardiograms, cardiac MRI machines are expensive and not available for many patients, especially those in rural areas, so we had hoped that AI could reduce the need for it,” said Alan Kwan, MD, assistant professor in the Department of Cardiology in the Smidt Heart Institute at Cedars-Sinai and co-senior author of the study. “Our results showed the limited powers of AI in this area.”
A study in the Journal of Orthopaedic Research uses a noninvasive, nonradioactive imaging-based method to measure the structure and function of the Achilles tendon in professional ballet dancers. The method could potentially be developed to help prevent injuries and improve rehabilitation efforts in athletes, as well as in the general public.
The study involved what is called multi-echo ultrashort echo time (UTE) magnetic resonance imaging (MRI) to assess collagen and other components of the Achilles tendon. These structural UTE MRI assessments were combined with functional assessments of the Achilles tendon based on sheer wave elastography (SWE) ultrasound, which measures tendon stiffness.
Professional dancers tended to have more tendon stiffness compared with non-dancers, consistent with prior observations of a training effect from repeated loading with exercise. UTE MRI measures corresponded with the degree of stiffness from SWE ultrasound.
“These findings highlight the potential of integrating UTE and SWE imaging to investigate tendon structure‐function relationships and adaptations to mechanical loading,” the authors write. “Enhanced structure‐function assessment of tendon health and injury status could improve rehabilitation protocols or injury prevention strategies for athletes, including professional dancers.”
The time to carry out diagnostic MRI scans for dementia can be cut to one third of their standard length, according to a new study led by UCL researchers.
The findings, published in Alzheimer’s & Dementia, have been described as a step towards ending ‘the postcode lottery in dementia diagnosis’. Shorter scans would be easier and more comfortable for patients and also enable more people to be scanned at a lower cost. The team behind the study say this could at least double the number of dementia scans able to be done in one day.
Senior author Professor Nick Fox, Director of the UCL Dementia Research Centre at the UCL Queen Square Institute of Neurology, said: “As more treatments that can slow or change the course of dementia are being developed, it’s important to make sure MRI scans are available to everyone. This is because people living with dementia often need an MRI scan as part of their diagnosis before they can access these treatments.
“To help make this possible, our team carried out the first study looking at how new imaging techniques – called parallel imaging – could speed up MRI scans in clinics. Their goal is to move closer to a future where every person with dementia can get a diagnosis through a scan.”
MRI scans often play a key role in an accurate dementia diagnosis, including ruling out other causes of symptoms and assisting in diagnosing the type of dementia. Emerging disease-modifying treatments such as lecanemab and donanemab also require an MRI scan before starting treatment and for safety monitoring during the course of treatment. Reducing the cost of scanning would contribute to lowering the total cost of delivering for such treatments.
The ADMIRA study (Accelerated Magnetic Resonance Imaging for Alzheimer’s disease), part funded by Alzheimer’s Society’s Heather Corrie Impact Fund, aimed to understand the reliability of fast MRI scans compared to standard-of-care clinical scans. The neurologists on the study were joined by co-authors from the UCL Hawkes Institute and the UCL Advanced Research Computing Centre in the faculty of Engineering.
The research team scanned 92 people in an outpatient setting where an MRI brain scan was planned as part of their routine clinical assessment. The accelerated scans were carried out and enhanced to increase the quality of the image using new scanning methods. Three neuroradiologists examined these scans, and weren’t aware if they were looking at fast or standard-of-care scans.
Co-author Professor Geoff Parker (UCL Hawkes Institute and UCL Medical Physics and Biomedical Engineering) said: “Our research has taken advantage of recent breakthroughs in scanner technology. Our task was to work out just how fast we could scan while maintaining image quality good enough for diagnosis.”
The team found that the quicker scans reduced time in the scanner by 63% and they were as reliable as the standard-of-care scans for diagnosis and visual ratings.
First author Dr Miguel Rosa-Grilo (UCL Queen Square Institute of Neurology) said: “We were confident that the new scan would prove non-inferior to the standard scan, given the high image quality – but it was remarkable how well it performed.”
Richard Oakley, Associate Director of Research and Innovation at Alzheimer’s Society, said: “Dementia is the UK’s biggest killer, but one in three people living with the condition haven’t had a diagnosis. An early and accurate diagnosis isn’t just a label, it’s the first step to getting vital care, support and treatment.
“While MRIs aren’t the only way to diagnosis dementia, very few people with concerns about their cognitive health are offered one as part of the diagnosis process, mainly because they are expensive and not widely available. These faster MRIs, which take less than half the time of standard scans, could help end this postcode lottery in dementia diagnosis, cut costs and potentially give more people access to them.
“MRI scans can be an uncomfortable and daunting experience for patients, so anything we can do to make it an easier process is really positive.
“So far, this shortened MRI scan has been tested at one specialist centre with one type of MRI scanner, so more research is needed to make sure this works across different types of scanners and a diverse range of people. We’re hugely encouraged by this progress and eager to see how it continues.”
The team will now build on their early results by making sure the approach works across different types of MRI machines, so it can benefit as many hospitals and clinics as possible.
Photo by Mariana Kurnyk: https://www.pexels.com/photo/two-baked-breads-1756062/
A research team led by the University of Nottingham has used magnetic resonance imaging (MRI) to better understand the impact a gluten free diet has on people with coeliac disease, which could be the first step towards finding new ways of treating the condition.
Coeliac disease is a chronic condition affecting around one person in every 100 in the general population. When people with coeliac disease eat gluten, which is found in pasta and bread, their immune system produces an abnormal reaction that inflames and damages the gut tissue and causes symptoms such as abdominal pain and bloating.
The only treatment is a life- long commitment to a gluten free diet, which helps recovery of the gut tissue but still leaves many patients with gastrointestinal symptoms.
Luca Marciani, Professor of Gastrointestinal Imaging at the University, led the study. He said: “Despite being a common chronic condition, we still don’t precisely know how coeliac disease affects the basic physiological functioning of the gut and how the gluten free diet treatment may further change this.
“We launched the MARCO study to try and address this issue, by using MRI along with gut microbiome analysis to give us new insights into how a gluten-free diet affects people with coeliac disease.”
The team recruited 36 people who had just been diagnosed with coeliac disease and 36 healthy volunteers to participate in the study. Images were taken of their guts with MRI, along with blood and stool samples. The patients then followed a gluten free diet for one year and came back to repeat the study. The healthy participants came back one year later too and repeated the study, but they did not follow any diet treatment.
The study found that the newly diagnosed patients with coeliac disease had more gut symptoms, more fluid in the small bowel and that the transit of food in the bowel was slower than in the healthy controls.
The microbiota (the ‘bugs’ living in the colon) of the patients showed higher levels of ‘bad bugs’ such as E.coli. After one year of a gluten free diet, gut symptoms, bowel water and gut transit improved in the patients, but without returning to normal values. But the gluten free diet also reduced some of the ‘good bugs’ in the microbiota, such as Bifidobacteria associated with reduced intake of starch and wheat nutrients, due to the different diet.
The patient study was conducted by Radiographer Dr Carolyn Costigan, from Nottingham University Hospitals, as part of her PhD studies at the University of Nottingham.
It was particularly interesting to see how the imaging results on gut function correlated with changes in the ‘bugs’ in the colon microbiota. The findings increase our understanding of gut function and physiology in coeliac disease and open the possibility of developing prebiotic treatments to reverse the negative impact of the gluten free diet on the microbiome.”
Luca Marciani, Professor of Gastrointestinal Imaging
Dr Frederick Warren from the Quadram Institute, which contributed to the research, said: “This study is the result of an exciting and innovative research collaboration bringing together medical imaging technology and gut microbiome analysis. We provide important insights which pave the way for future studies which may identify novel approaches to alleviate long-term symptoms in coeliac patients.”
A technique that uses MRI as a guide can make radiotherapy safer for prostate cancer patients by better aiming beams at the prostate while sparing nearby tissue in the bladder, urethra, and rectum. That is the finding of a thorough analysis of all published clinical trials of the technique, called magnetic resonance–guided daily adaptive stereotactic body radiotherapy (MRg-A-SBRT). The analysis is published in CANCER.
By providing detailed images, MRg-A-SBRT can be used to adjust a patient’s radiation plan every day to account for anatomical changes and to monitor the position of the prostate in real time while the radiation beam is on to ensure that treatment is being directed accurately to the prostate. Although MRg-A-SBRT is becoming more popular and multiple clinical trials have tested it, it is unclear whether the technique, which requires more time and resources than standard procedures, has an impact on clinical outcomes and side effects compared with other ways of delivering radiation.
To investigate, Jonathan E. Leeman, MD, of the Dana-Farber Cancer Institute and Brigham and Women’s Hospital, and his colleagues combined data from 29 clinical trials testing MRg-A-SBRT versus conventional CT-guided treatment, with a total of 2457 patients.
MRg-A-SBRT was associated with significantly fewer urinary and bowel side effects in the short term following radiation. Specifically, there was a 44% reduction in urinary side effects and a 60% reduction in bowel side effects.
“The study is the first to directly evaluate the benefits of MR-guided adaptive prostate radiation in comparison to another more standard and conventional form of radiation, and it provides support for use of this treatment in the management of prostate cancer,” said Dr Leeman.
Dr Leeman noted that the study also raises further questions regarding this type of treatment. For example, will the short-term benefits lead to long-term benefits, which are more impactful for patients? Longer follow-up will help answer this question because MRg-A-SBRT is a relatively new treatment. Also, which aspect of the technology is responsible for the improved outcomes seen in clinical trials? “It could potentially be the capability for imaging-based monitoring during the treatment or it could be related to the adaptive planning component. Further studies will be needed to disentangle this,” said Dr Leeman.
An accompanying editorial discusses the analysis’ findings, weighs the potential benefits and shortcomings of adopting this treatment strategy for patients, and questions the value of broad adoption.
Results from a clinical trial showed that ultrasound scans are effective in prostate cancer diagnosis, which would be a cheaper option than MRI for low- and middle income countries. The study is published in Lancet Oncology.
“MRI scans are one of the tests we use to diagnose prostate cancer,” said Professor Hashim Ahmed, lead author of the study and Chair of Urology at Imperial College London. “Although effective, these scans are expensive, take up to 40 minutes to perform and are not easily available to all. Also, there are some patients who are unable to have MRI scans such as those with hip replacements or claustrophobia fears. As cancer waiting lists build as a result of the COVID pandemic, there is a real need to find more efficient and cheaper tests to diagnose prostate cancer.
“Our study is the first to show that a special type of ultrasound scan can be used as a potential test to detect clinically significant cases of prostate cancer. They can detect most cases of prostate cancer with good accuracy, although MRI scans are slightly better.
“We believe that this test can be used in low and middle income settings where access to expensive MRI equipment is difficult and cases of prostate cancer are growing.”
Prostate cancer develops slowly and symptoms such as the blood in the urine do not appear until the disease has developed. It usually affects men over 50 and often men with a family history of the disease. Black men are disproportionately impacted by the disease and prostate cancer deaths now exceed those from breast cancer.
One of the principal means of prostate cancer diagnosis is a multi-parametric MRI (mpMRI) scan. However, the 40-minute scan costs £350–450 (R7000-9000).
This new study tested multiparametric ultrasound (mpUSS) to image the prostate. Elastography examines tissue hardness, doppler and contrast-enhancement with microbubbles measures blood flow. As cancers are denser and have greater blood supply, they show up more clearly. While mpUSS is more widely available than mpMRI, no large-scale studies have been done thus far to validate its effectiveness as a test to detect prostate cancer cases.
For the trial the team recruited 370 men at risk of prostate cancer. They were identified following initial tests such as a prostate-specific antigen (PSA) test and/or an abnormal digital rectal examination.
The men underwent both mpUSS and mpMRI scans at separate visits. This was then followed by biopsies for 257 patients who had a positive mpUSS or mpMRI test result. Cancer was detected in 133 men, with 83 men diagnosed with clinically significant cancer.
Individually, mpUSS detected 66 cases of clinically significant cancer compared to mpMRI which detected 77 cases.
Although mpUSS detected 4.3% fewer clinically-important prostate cancers compared to mpMRI, this method would lead to 11.1% more patients being biopsied as a result of false positives from the mpUSS.
The researchers believe that mpUSS could be an alternative to mpMRI as a first test for patients at risk of prostate cancer, particularly where mpMRI cannot be carried out. As both imaging tests missed clinically-important cancers detected by the other, using both would increase the detection of clinically-important prostate cancers overall.
Significant alterations in the brain’s white matter in adolescents with autism spectrum disorder (ASD). Credit: RSNA and researcher, Clara Weber
Using specialised MRI, researchers found significant changes in the microstructure of the brain’s white matter, especially in thecorpus callosum in adolescents and young adults with autism spectrum disorder (ASD) compared to controls. This research will be presented next week at the annual meeting of the Radiological Society of North America (RSNA).
“One in 68 children in the U.S. is affected by ASD, but high variety in symptom manifestation and severity make it hard to recognise the condition early and monitor treatment response,” explained Clara Weber, postgraduate research fellow at Yale University School of Medicine. “We aim to find neuroimaging biomarkers that can potentially facilitate diagnosis and therapy planning.”
Researchers reviewed diffusion tensor imaging (DTI) brain scans from a large dataset of patients between the age of six months and 50 years. DTI is an MRI technique that measures connectivity in the brain by detecting how water moves along its white matter tracts. Water molecules diffuse differently through the brain, depending on the integrity, architecture and presence of barriers in tissue.
“If you think of gray matter as the computer, white matter is like the cables,” Weber said. “DTI helps us assess how connected and intact those cables are.”
For the study, clinical and DTI data from 583 patients from four existing studies of distinct patient populations were analysed: infants (median age 7 months), toddlers (median age 32 months), adolescents, and young adults.
“One of the strengths of our study is that we looked at a wide range of age groups, not just school-aged children,” Weber said.
To assess the influences of age and ASD diagnosis on white matter microstructure, the research team created fractional anisotropy, mean diffusivity and radial diffusivity maps using data from the four studies.
Fractional anisotropy is the extent water diffusion is restricted to just one direction. A value of zero means that diffusion is unrestricted in all directions, while one means that diffusion is unidirectional. Mean diffusivity is the overall mobility of water molecules, indicating how densely cells are packed together. Radial diffusivity is the extent water diffuses perpendicular to a white matter tract.
“When white matter integrity is disrupted, we see more water diffusing perpendicularly, which translates to a higher radial diffusivity,” Weber said.
The key finding of the analysis was reduced fractional anisotropy within the anterior/middle tracts of the corpus callosum in adolescent and young adult ASD patients compared to individuals in the control group. The corpus callosum is a thick bundle of nerve fibers that connects and allows the two sides of the brain to communicate. Corresponding increases in ASD-related mean diffusivity and radial diffusivity were found in young adults.
“In adolescents, we saw a significant influence of autism,” Weber said. “In adults, the effect was even more pronounced. Our results support the idea of impaired brain connectivity in autism, especially in tracts that connect both hemispheres.”
Compared to controls, no reduction in fractional anisotropy was seen in the same tracts in toddlers and infants with ASD.
The researchers hope the findings can help improve early diagnosis of ASD and provide potential objective biomarkers to monitor treatment response.
“We need to find more objective biomarkers for the disorder that can be applied in clinical practice,” Weber said.
According to a new study, the MRI-derived standardised non-invasive clear cell likelihood score (ccLS) is correlated with the growth rate of small renal masses (cT1a, <4 cm) and could help guide personalised management.
The study was published in the American Roentgen Ray Society’s American Journal of Roentgenology. Extracted from clinical reports, “the ccLS scores the likelihood that the small renal mass represents clear cell renal cell carcinoma, from 1 (very unlikely) to 5 (very likely),” explained corresponding author Ivan Pedrosa from the University of Texas Southwestern Medical Center at Dallas. “Small renal masses with lower ccLS may be considered for active surveillance, whereas small renal masses with higher ccLS may warrant earlier intervention.”
The team’s retrospective study included consecutive small renal masses assigned a ccLS on clinical MRI exams performed from June 2016 to November 2019. Tumour size measurements were obtained from available prior and follow-up cross-sectional imaging examinations, up to June 2020.
Among 389 small renal masses in 339 patients (198 men, 141 women; median age, 65 years) on active surveillance that were assigned a ccLS on clinical MRI examinations, those with ccLS4-5 grew significantly faster (9% diameter, 29% volume yearly) than those with ccLS1-2 (5% diameter, p<.001; 16% volume, p<.001) or ccLS3 (4% diameter, p<.001; 15% volume, p<.001).
With a lack of validated imaging markers to characterise biologic aggressiveness of small renal masses hindering medical decision making, “growth is associated with ccLS in small renal masses,” the authors reiterated, “with higher ccLS correlating with faster growth.”
A new study from Karolinska Institutet in Sweden suggests that early magnetic resonance imaging (MRI) of the heart can greatly increase the rate of diagnosis of broken-heart syndrome, which can happen when there is no obvious cause in the coronary artery.
Myocardial infarction is typically caused by a blockage of the coronary artery by a blood clot. However, in up to 10% of all myocardial infarctions, no obvious cause in the coronary artery is found, and so the working diagnosis MINOCA (myocardial infarction with non-obstructive coronary arteries) is given, which can subsequently lead to one of several diagnoses.
Most of these patients are women, many of whom are diagnosed with takotsubo cardiomyopathy (broken-heart syndrome), characterised by reduced heart function that is likely stress-related, presenting the same symptoms as a standard heart attack.
“Around 80 to 90% of broken-heart sufferers are women, and the disease is associated with mental stress,” said principal investigator Per Tornvall, senior physician and professor at the Department of Clinical Science and Education, Stockholm South General Hospital, Karolinska Institutet. “There also seems to be a link to hypersensitivity towards stress caused by low estrogen levels. Unfortunately, research on the investigation and treatment of myocardial infarction is often done on men, while female heart disease is less studied.”
In a prior study with 150 patients, cardiovascular magnetic resonance (CMR) is often done when examining patients with MINOCA. CMR conducted approximately 10 days after onset can result in a diagnosis in under half the patients, normally takotsubo or myocarditis (inflammation of the heart muscle), Now, the same researchers have tested a new, more sensitive CMR technique two to four days after onset on a comparable group of 148 patients. They found that 77% of the patients could be diagnosed: 35% of takotsubo and 17% of myocardial inflammation, compared with 19 and 7%, respectively, in the first study.
“We don’t know how much effect the improved CMR technique has, but the results suggest that with early examination more patients can get a correct diagnosis and therefore the right treatment,” says Professor Tornvall. “The next step is for us to develop the CMR examination with pharmacological stress of the heart. This will enable us to study the smallest of the blood vessels and hopefully find a cause for the 23% who received no diagnosis.”
Journal information: Peder Sörensson et al. Early Comprehensive Cardiovascular Magnetic Resonance Imaging in Patients With Myocardial Infarction With Nonobstructive Coronary Arteries, JACC: Cardiovascular Imaging (2021). DOI: 10.1016/j.jcmg.2021.02.021
