High altitude cerebral edema (HACE) is a severe and often fatal condition that can affect mountain climbers, hikers, skiers and travelers at high altitudes—typically above 7,000 feet, or 2,300 meters.
HACE results from swelling of brain tissue due to leakage of fluids from the capillaries. Symptoms include headache, loss of coordination and decreasing levels of consciousness.
"HACE is a life-threatening condition," said Michael Knauth, M.D., Ph.D., from the University Medical Center's Department of Neuroradiology in Goettingen, Germany. "It usually happens in a hostile environment where neither help nor proper diagnostic tools are available."
Dr. Knauth and colleagues at the University Hospitals in Goettingen and Heidelberg, Germany, compared brain MRI findings among four groups of mountaineers: climbers with well documented episodes of HACE; climbers with a history of high altitude illness; climbers with a history of severe acute mountain sickness (AMS); and climbers with a history of isolated high altitude pulmonary edema (HAPE), a life-threatening accumulation of fluid in the lungs that occurs at high altitudes. Two neuroradiologists assessed the brain MRI findings without knowing the status of the mountaineers and assigned a score based on the number and location of any microhemorrhages.
"In most cases, these microhemorrhages are so small that they are only visible with a special MRI technique called susceptibility-weighted imaging," Dr. Knauth said. "With this technique, the microhemorrhages are depicted as little black spots."
The MRI results showed brain microhemorrhages almost exclusively in HACE survivors. Of the 10 climbers with a history of HACE, eight had evidence of microhemorrhages on MRI. The other two had uncertain results. Only two of the remaining 26 climbers were positive for microhemorrhages.
"It was previously thought that HACE did not leave any traces in the brains of survivors," Dr. Knauth said. "Our studies show that this is not the case. For several years after, microhemorrhages or microbleeds are visible in the brains of HACE survivors."
Survivors of the most clinically severe cases of HACE had the most prominent evidence of microhemorrhages on MRI. The bleeds were found predominantly in the corpus callosum, the thick band of nerve fibers that connects the right and left halves of the brain, and showed a characteristic distribution different from other vascular diseases like vasculitis, or blood vessel inflammation.
"The distribution of microhemorrhages is a new and sensitive MRI sign of HACE and can be detected years after HACE," Dr. Knauth said. "We will further analyze our clinical and MRI data on patients with acute mountain sickness, which is thought to be a precursor of HACE."
In the meantime, Dr. Knauth does not think HACE survivors need to give up climbing.
"We cannot give such a strong recommendation," he said. "However, mountaineers who have already experienced HACE once should acclimatize to the altitude very slowly."
Coauthors are Kai Kallenberg, M.D., Peter Bartsch, M.D., and Kai Schommer, M.D.
Note: Copies of RSNA 2012 news releases and electronic images will be available online at RSNA.org/press12 beginning Monday, Nov. 26.
RSNA is an association of more than 50,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill.
Editor's note: The data in these releases may differ from those in the published abstract and those actually presented at the meeting, as researchers continue to update their data right up until the meeting. To ensure you are using the most up-to-date information, please call the RSNA Newsroom at 1-312-949-3233.
For patient-friendly information on MRI of the brain, visit RadiologyInfo.org.
Linda Brooks | EurekAlert!
Researchers show p300 protein may suppress leukemia in MDS patients
28.03.2017 | University of Miami Miller School of Medicine
When writing interferes with hearing
28.03.2017 | Université de Genève
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Physics and Astronomy
28.03.2017 | Health and Medicine
28.03.2017 | Life Sciences