MRI

Adenosine rest-stress perfusion may represent nearly half the imaging volume at some clinics, but due to safety questions some physicians are sticking with dobutamine for pharmacological stress testing.

British researchers have used T2* measures of cardiac iron loading to show the value of a new drug treatment for b-thalassemia, a genetic blood disorder. The laborious clinical trial involved transporting a mobile MRI system three times from London to the Mediterranean island of Sardinia.

In cardiac catheterization, it's known as the money shot: coronaries floating in space with the shadow of the heart behind them. It is also the hardest shot to get, because of the amount of tissue that x-rays must penetrate. As patients get larger, the going gets tougher. But for MRI, capturing this shot has become a piece of cake.

Physicians have yet to find a simple, inexpensive test to screen for the risk of sudden cardiac death. But they are learning how cardiac MR imaging may help stratify risk and guide treatment for conditions that can strike without warning.

Delayed-enhancement MRI creates a clear picture of the atrial scarring produced during pulmonary vein RF ablation, according to researchers at Beth Israel Deaconess Medical Center in Boston.

Researchers from Seoul National University Medical Center found that ultrasound-only detected breast cancers are not very sensitive to a mammography computer-aided detection system.

Results from a prospective study bolster confidence that a negative adenosine perfusion contrast MR test means patients have a good chance of surviving the next six months without major heart problems.

Football coaches can't foresee when their players might get injured. But musculoskeletal radiologists may be able to predict who is going to hurt the most, and where.

I have a personal interest in finding better ways of treating stroke. My favorite uncle was struck down by one in 1994, just as I was reporting on how the combination of tPA and head CT could produce miracles.

Figuring out how to treat postinfarction left ventricular remodeling using delayed-enhancement cardiac MR is not so cut and dried as it seems. Bright signal may signify dead myocardial tissue during DE-MR viability studies, but bright and dark myocardium both have stories to tell when dealing with remodeling.

The 2006 Society for Cardiovascular Magnetic Resonance meeting showed that the most productive areas of cardiac MR research are those that exploit the modality's inherent strengths.

We have good news to report in this month's cover story: Research in stroke imaging is beginning to widen the window of time in which drug-based or mechanical therapy can be used to preserve brain function following an ischemic stroke. But we have bad news to report as well: More than a decade after research established the value of thrombolytic therapy to revascularize the brain and preserve brain tissue, the use of tissue plasminogen activator for stroke therapy remains stubbornly in the 2% range. Many victims go untreated for the nation's number three cause of death and a leading cause of serious long-term disability.

Parallel imaging has reduced acquisition time for contrast MR, making it possible to use 3D MR angiography in imaging infants with suspected congenital abnormalities.

Buffalo psychologist Jamie Shiffner, Ph.D., beat the odds. The acute stroke patient was lucky enough to have everything go right after being struck down. With ischemic stroke, time is brain. Within moments of Shiffner's collapse at home on the evening of April 11, 2005, millions of neurons in his brain began dying every minute. The left side of Shiffner's body went numb, and attempts to talk resulted in nonsense phrases.

MR imaging of pacemakers and implantable cardioverter devices is not for every imaging service. But the procedure is feasible, despite American College of Radiology recommendations to the contrary, according to a study from Oklahoma.

Tumors require new blood vessels in order to grow beyond a few millimeters in size. Once this "angiogenic switch" is thrown, a series of events occur that lead to the progression and spread of cancer. The vessels formed by tumors are not only larger and more numerous but also more permeable than normal vessels1 (Figure 1). Thus, when a patient with a tumor is injected with a gadolinium-chelate MR contrast agent, the tumor enhances more than the surrounding normal tissue.

Signal-to-noise ratio has long been the standard for gauging the performance of MR scanners. Its calculation, however, can be tedious, especially when several scanners are involved.

High-field MR perfusion imaging with arterial spin labeling (ASL) can be performed safely and effectively on clinical pediatric populations for several neurological indications, according to Harvard University researchers.

The skull is often thought of as packaging for the brain, but a new study suggests that the skull and brain are linked developmentally and evolutionarily.

Though an MR scanner is hardly cuddly, it could become a baby’s best friend. Or so Christopher Looney would say.

We all make mistakes, and some cost more than others. Now, researchers have peered inside the brain to see what happens at the moment we realize our error -- and its price. Their findings may have implications for understanding obsessive-compulsive disorder.

Medical imaging is poised to play a key role in drug research, including evaluating therapy and characterizing disease.

The market for 3T MRI is undoubtedly growing. Five years ago, few sites were using a 3T scanner for anything other than research. Now the higher field strength devices can be found in many clinical radiology departments and outpatient imaging clinics across the U.S. Clinical 3T is making inroads in Europe, too, though at a pace commensurate with its smaller MR base.

Whole-body MR scanners that operate at high field strengths are becoming widely available, and new 3T models have been launched in recent years. This generation of scanners offers exciting possibilities for radiological diagnosis while also posing challenges.

Neuroradiologists understand that high-grade tumors interrupt the blood-brain barrier, which presents as contrast enhancement on CT and MRI. Renewed interest in the phenomenon of permeability, however, has researchers looking beyond simple contrast enhancement and toward molecular mechanisms involved in permeability that may help them treat brain tumors more effectively.

An MR-based study has revealed associations between a gene variant and impulsive, violent behavior in humans, particularly males with a history of child abuse. The findings prompted National Institutes of Health director Dr. Elias A. Zerhouni to tout the power of imaging genomics to better understand brain circuitry underlying diversity in human temperament.

MR spectroscopy can help reduce breast MRI false positives, which tend to increase during certain times of the menstrual cycle, according to researchers at Memorial Sloan-Kettering Cancer Center.

Imaging women with MR while they perform stress maneuvers can identify and characterize unsuspected pelvic organ prolapse, compared with imaging them while at rest, according to a study presented in Phoenix at the annual meeting of the Society of Computed Body Tomography and Magnetic Resonance.

Stenting of the carotid artery may offer more than reduced stroke risk, especially to patients with impaired brain perfusion. Researchers have found that the procedure improves cognitive speed, verbal fluency, and delayed recall.

Your investment portfolio is tanking, and you question your stock choices. Perhaps an fMR scan can get you back on track.