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.
MR-guided focused ultrasound surgery is a safe, effective treatment for uterine fibroids. The number and size of fibroids do not affect outcome, according to a pair of studies presented at the 2005 RSNA meeting.
MR imaging has demonstrated a high sensitivity for detecting ductal carcinoma in situ, and it could play a complementary role to mammography in finding and evaluating this very common type of cancer, according to a study in The Breast Journal.
Nationwide, an estimated 80% of alcoholics are also chronic smokers. Yet research considering the relationship between addiction to both tobacco and alcohol is scant.
Among European radiologists, concerns about ionizing radiation exposure give MR an edge in specific applications, including colorectal cancer screening in younger patient populations. But in the U.S., such concerns have not dampened enthusiasm for CT, particularly in neurovascular studies.
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.
Radiologists can make a more accurate preoperative diagnosis of damage to knee cartilage by using four radiologic signs, according to a study from Duke University Medical Center. Using the signs to identify the extent and type of damage to knee cartilage makes interpreting MRI with a higher degree of accuracy easier for any radiologist, regardless of level of expertise.
MR imaging has a high sensitivity for detecting ductal carcinoma in situ and could play a complementary role to mammography in finding and evaluating this common type of cancer, according to a study published in Breast Journal.
A whole-body PET/CT scan can be used to stage and further pinpoint cancers spotted on optical colonoscopy, a research team for Essen University reported Monday. The team also reported that PET/CT scans may be useful in restaging recurrent breast cancer.
The most striking feature for me at ECR this year is the expansion of company-sponsored satellite meetings. Usually limited to lunch sessions, they now run in parallel to the proffered papers, competing with the scientific session marathon.
A small study from a breast cancer surveillance program of high-risk women found that annual MR imaging did not detect additional cancers beyond conventional screening with both mammography and clinical physical examination.
