In the report, the researchers describe the case of a 32-year-old man who wasn't wearing a helmet when his all-terrain vehicle crashed. Initially, his CT scans showed bleeding and swelling on the right side of the brain, which controls left-sided body movement. A week later, while the man was still in a coma, a conventional MRI scan showed brain bruising and swelling in the same area. When he awoke three weeks later, the man couldn't move his left leg, arm and hand.
"There are about 1.7 million cases of TBI in the country each year, and all too often conventional scans show no injury or show improvement over time even though the patient continues to struggle," said co-senior author and UPMC neurosurgeon David O. Okonkwo, M.D., Ph.D., associate professor, Department of Neurological Surgery, Pitt School of Medicine. "Until now, we have had no objective way of identifying how the injury damaged the patient's brain tissue, predicting how the patient would fare, or planning rehabilitation to maximize the recovery."
HDFT might be able to provide those answers, said co-senior author Walter Schneider, Ph.D., professor of psychology at Pitt's Learning Research and Development Center (LRDC), who led the team that developed the technology. Data from sophisticated MRI scanners is processed through computer algorithms to reveal the wiring of the brain in vivid detail and to pinpoint breaks in the cables, called fiber tracts. Each tract contains millions of neuronal connections.
"In our experiments, HDFT has been able to identify disruptions in neural pathways with a clarity that no other method can see," Dr. Schneider said. "With it, we can virtually dissect 40 major fiber tracts in the brain to find damaged areas and quantify the proportion of fibers lost relative to the uninjured side of the brain or to the brains of healthy individuals. Now, we can clearly see breaks and identify which parts of the brain have lost connections."
HDFT scans of the study patient's brain were performed four and 10 months after he was injured; he also had another scan performed with current state-of the-art diffusion tensor imaging (DTI), an imaging modality that collects data points from 51 directions, while HDFT is based on data from 257 directions. For the latter, the injury site was compared to the healthy side of his brain, as well as to HDFT brain scans from six healthy individuals.
Only the HDFT scan identified a lesion in a motor fiber pathway of the brain that correlated with the patient's symptoms of left-sided weakness, including mostly intact fibers in the region controlling his left leg and extensive breaks in the region controlling his left hand. The patient eventually recovered movement in his left leg and arm by six months after the accident, but still could not use his wrist and fingers effectively 10 months later.
Memory loss, language problems, personality changes and other brain changes occur with TBI, which the researchers are exploring with HDFT in other research protocols.
UPMC neurosurgeons also have used the technology to supplement conventional imaging, noted Robert Friedlander, M.D., professor and chair, Department of Neurological Surgery, Pitt School of Medicine, and UPMC Endowed Professor of Neurosurgery and Neurobiology. He is not a member of this research study.
"I have used HDFT scans to map my approach to removing certain tumors and vascular abnormalities that lie in areas of the brain that cannot be reached without going through normal tissue," he said. "It shows me where significant functional pathways are relative to the lesion, so that I can make better decisions about which fiber tracts must be avoided and what might be an acceptable sacrifice to maintain the patient's best quality of life after surgery."
Dr. Okonkwo noted that the patient and his family were relieved to learn that there was evidence of brain damage to explain his ongoing difficulties. The team continues to evaluate and validate HDFT's utility as a brain imaging tool, so it is not yet routinely available.
"We have been wowed by the detailed, meaningful images we can get with this technology," Dr. Okonkwo said. "HDFT has the potential to be a game-changer in the way we handle TBI and other brain disorders."
Co-authors include lead author Samuel L. Shin, Ph.D., Allison J. Hricik, M.S., Megan Maserati, and Ava M. Puccio, Ph.D., all of the Department of Neurological Surgery; Timothy Verstynen, Ph.D., Sudhir Pathak, M.S., and Kevin Jarbo, all of LRDC; and Sue R. Beers, of the Department of Psychiatry, all of the University of Pittsburgh. The study was funded by the Defense Advanced Research Projects Agency.
For video and images, contact Anita Srikameswaran at SrikamAV@upmc.edu or Tim Betler at BetlerTC@upmc.edu.
For more information about the Schneider lab's HDFT research efforts, go to www.hdft.info
Anita Srikameswaran | EurekAlert!
Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center
Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy