Study finds chronic abnormal brain blood flow in Gulf War veterans

September 13, 2011, Radiological Society of North America

Blood flow abnormalities found in the brains of veterans with Gulf War illness have persisted 20 years after the war, and in some cases have gotten worse, according to a new study published online in the journal Radiology.

"We confirmed that abnormal continued or worsened over the 11-year span since first being diagnosed, which indicates that the damage is ongoing and lasts long term," said principal investigator Robert W. Haley, M.D., chief of epidemiology in the Departments of Internal Medicine and Clinical Sciences at the University of Texas (UT) Southwestern Medical Center in Dallas. "We also identified a special MRI procedure that better diagnoses and distinguishes between the three main types of Gulf War illness."

Gulf War illness is a poorly understood chronic condition associated with exposure to neurotoxic chemicals and nerve gas. It affects an estimated 25 percent of the 700,000 military personnel deployed to the 1991 Persian Gulf War, according to the U.S. Department of Affairs' scientific advisory committee.

There are three main syndromes associated with Gulf War illness, producing a variety of symptoms, including fatigue, neuropathic pain, memory and concentration deficits, balance disturbances and depression.

The hippocampus is the part of the brain responsible for forming long-term memories and helping with . Many Gulf War illness , such as memory loss, confusion, irritability and disorders in motion control suggest impairment of the hippocampus.

In 1998, Dr. Haley's research team published a study using single computed tomography (SPECT) to assess hippocampal blood flow in veterans with Gulf War Syndrome. For the current study, the researchers used a novel technique called arterial spin labeled (ASL) MRI to assess hippocampal regional (rCBF) in 13 control participants and 35 patients with Gulf War syndromes 1 (impaired cognition), 2 (confusion-ataxia) and 3 (central neuropathic pain).

Each patient received intravenous infusions of saline in an initial session, and physostigmine in a second session 48 hours later. Physostigmine is a short-acting cholinesterase inhibitor, used to test the functional integrity of the cholinergic system, a neurotransmitter system involved in the regulation of memory and learning.

"ASL scanning after giving this medication is particularly well suited to diagnosing Gulf War illness, because it picks up brain abnormalities too subtle for regular MRI to detect," said co-author Richard W. Briggs, Ph.D., professor of radiology at UT Southwestern. "This allows us to make the diagnosis in a single two-hour session without the need for exposure to ionizing radiation."

The findings replicated the results of the initial SPECT study of largely the same group of veterans. The results showed that abnormal hippocampal blood flow persisted and may have progressed 11 years after initial testing and nearly 20 years after the Gulf War, suggesting chronic alteration of hippocampal blood flow.

Physostigmine significantly decreased rCBF in and veterans with syndrome 1, but significantly increased rCBF in the right hippocampus of veterans with syndrome 2 in the original study. The abnormal increase in rCBF was now found to have progressed to the left hippocampus with syndrome 2 and to both hippocampi of the veterans with syndrome 3.

"Having an objective diagnostic test allows researchers to identify ill veterans for future clinical trials to test possible treatments," Dr. Haley said. "It is also critical for ongoing genomic studies to see why some people are affected by chemical exposures, and why others are not."

More information: "Hippocampal Dysfunction in Gulf War Veterans: Investigation with ASL Perfusion MR Imaging and Physostigmine Challenge." at radiology.rsna.org/

Related Stories

Recommended for you

Forces from fluid in the developing lung play an essential role in organ development

January 23, 2018
It is a marvel of nature: during gestation, multiple tissue types cooperate in building the elegantly functional structures of organs, from the brain's folds to the heart's multiple chambers. A recent study by Princeton researchers ...

Anemia discovery offers new targets to treat fatigue in millions

January 22, 2018
A new discovery from the University of Virginia School of Medicine has revealed an unknown clockwork mechanism within the body that controls the creation of oxygen-carrying red blood cells. The finding sheds light on iron-restricted ...

More surprises about blood development—and a possible lead for making lymphocytes

January 22, 2018
Hematopoietic stem cells (HSCs) have long been regarded as the granddaddy of all blood cells. After we are born, these multipotent cells give rise to all our cell lineages: lymphoid, myeloid and erythroid cells. Hematologists ...

How metal scaffolds enhance the bone healing process

January 22, 2018
A new study shows how mechanically optimized constructs known as titanium-mesh scaffolds can optimize bone regeneration. The induction of bone regeneration is of importance when treating large bone defects. As demonstrated ...

Researchers illustrate how muscle growth inhibitor is activated, could aid in treating ALS

January 19, 2018
Researchers at the University of Cincinnati (UC) College of Medicine are part of an international team that has identified how the inactive or latent form of GDF8, a signaling protein also known as myostatin responsible for ...

Bioengineered soft microfibers improve T-cell production

January 18, 2018
T cells play a key role in the body's immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.