MRI News

MRI Shows Brain Alterations in Personnel Who Developed Neurological Symptoms in Cuba

Brain imaging of 40 US government personnel who experienced a host of neurological symptoms after possible exposure from an unknown source while serving in Cuba revealed significant differences in brain tissue and connectivity when compared with healthy individuals, according to a new report from researchers at the University of Pennsylvania’s Perelman School of Medicine. The findings were published in JAMA.

“The areas implicated in the patients’ brains, namely the cerebellum as well as the visuospatial and auditory networks, align with the neurological symptoms that were observed in the patients,” says lead author Ragini Verma, PhD, a professor of radiology and head of the DiCIPHR (Diffusion and Connectomics in Precision Healthcare Research) imaging lab at Penn. “These differences persisted even when people with some history of brain injury were excluded from the analysis.”

In 2016, several US government personnel serving in Havana, Cuba, and their family members began to report a variety of neurological symptoms, including difficulty with concentration and memory, dizziness, visual issues, and balance problems. The symptoms were linked to sudden, intensely loud noises heard in their homes and hotel rooms, which State Department officials later referred to as a “sonic attack” or “directional phenomena,” though the specifics of the alleged event remain unsolved.

After initial examinations, the patients were sent to Penn’s Center for Brain Injury and Repair for evaluation, treatment, and rehabilitation in the summer of 2017, under the direction of center director and study coauthor Douglas H. Smith, MD, the Robert A. Groff Professor of Teaching and Research in Neurosurgery.

A 2018 JAMA report published by Penn researchers documented the neurological symptoms experienced by 21 patients who had reported exposure to the mysterious phenomena in Cuba. Summing up these findings, the symptoms were “similar to those found in persistent concussion syndrome, yet there was no evidence of blunt head trauma,” according to Smith.

As part of the investigation into their signs and symptoms, the patients also underwent advanced neuroimaging with multimodal MRI at Penn prior to receiving any comprehensive rehabilitation treatment. This retrospective analysis compared the brain images of 40 potentially-exposed personnel with 48 healthy individuals who were not exposed and did not demonstrate these signs and symptoms.

The group-based analysis, published in the new 2019 JAMA study, used various computational tools to examine structural, diffusion, and functional MRI images, finding statistically significant differences in brain volume, tissue properties, and connectivity between the patients and a healthy control group. There was reduced white matter volume in the affected patients, along with a pattern of differences in measures of water diffusion in the tissue. The imaging also revealed lower functional connectivity in the visuospatial and auditory subnetworks. Notably, differences in tissue volume, water diffusion, and connectivity were found in the cerebellum, the part of the brain responsible for performing voluntary tasks such as walking and writing.

“The cerebellar findings in this neuroimaging study are notable, given that a number of the patients evaluated exhibited abnormalities in balance and the coordinated movement of the eyes, both of which are associated with cerebellar dysfunction in the brain,” says study coauthor Randel Swanson, DO, PhD, an assistant professor of physical medicine and rehabilitation at Penn, and a staff physician at the VA Medical Center in Philadelphia.

According to Verma, the pattern of differences found in this study does not resemble imaging-based investigations of any other pathology, such as concussion and traumatic brain injury.

“These findings may represent something not seen before,” Smith says.

Verma likens the brain to a highway system, comprising roads (white matter) and traffic. Structural MRI provides information about the size of the roads, while diffusion imaging provides insight into the road conditions and how they are connected. An injury to the brain could contribute to a deterioration in the condition of the roads (reflected in white matter differences), leading to an alternate traffic pattern (altered functional connectivity). Therefore, Verma says, a multimodal investigation is essential to see a more complete picture of the injury. As the brain recovers, while the traffic pattern may go back to normal, the overuse of some roads may lead to wear and tear, or compensatory changes in the brain.

“It’s hard to tell where the problem started; the brain differences observed could be an immediate effect of the brain injury, or it could be a compensatory effect of the recovery process,” Verma says. “It’s very difficult to say, especially with a retrospective, heterogeneous study, where people were included at various times after potential exposure. The important thing is that we did see differences at the group level.”

— Source: Penn Medicine

MRI Technology Identifies Genetic Causes of High Liver Iron

A study into the mechanism behind liver iron accumulation confirms three genes are responsible for iron overload in the liver. High liver iron, often referred to as the Celtic Curse, is common in the Irish population, with as many as 1 in 8 suffering from this disease. Previous research has shown that United Kingdom (UK) prevalence of iron overload is 4.8%.

Researchers from Perspectum, together with collaborators from the University of Westminster, University College London, and Lund University in Sweden, were able to noninvasively and rapidly quantify liver iron content using Perspectum Diagnostics’ LiverMultiScan multiparametric MRI technology. More than 8,000 participants who had previously provided DNA samples to the UK Biobank were scanned. Three genes were associated with increased risk of developing higher liver iron content.

“Excess iron is a silent—and often deadly—cause of liver disease,” says Neil McClements, CEO at Haemochromatosis UK. “This study underlines the value to patients of rapidly identifying elevated liver iron through noninvasive MRI screening. Faster diagnosis is a significant benefit to people affected by genetic hemochromatosis, the UK’s most prevalent underdiagnosed genetic condition. Early diagnosis of iron overload caused by genetic hemochromatosis saves lives.”

The study shows the causes of elevated liver iron are systemic rather than liver specific, with the same genes associated with other diseases such as diabetes, high blood pressure, and heart disease. This may lead to new strategies to manage these conditions. New treatments from companies such as La Jolla are currently in clinical trials. This is important, especially when a patient has multiple liver diseases, eg, iron overload and fatty liver disease. The study also provides support for multiparametric MRI as a noninvasive and radiation-free technique for quantifying liver iron content.

“Identifying patients at risk for iron overload allows preventive action to be taken, both in the form of giving blood, and with lifestyle changes such as reducing red meat consumption,” says Rajarshi Banerjee, BMBCh, MA, MSc, PhD, Perspectum’s CEO.

— Source: Perspectum Diagnostics