Archive for September, 2010

Considerations When Choosing an MRI Centre

By Kim, September 30th, 2010

Not all MRI’s are created equal. Important factors to consider when choosing where to have your MRI include the strength of the facility’s magnet, the protocols which they offer, whether they have invested in dedicated coils specific to the body part being imaged, as well as the overall design of the magnet. Dr. Jason Clement reviews these considerations in the following video.

MR Enterography, an important option for Crohn’s Disease sufferers.

By Kim, September 08th, 2010

Crohn’s disease is a chronic inflammatory bowel disease that affects more than 80,000 Canadians.  The disease is characterized by inflammation and lesions on the intestinal walls throughout the length of the gastrointestinal tract, which can be complicated by strictures, abscess formation and fistulae.  It is a complex pathologic process with an unpredictable lifelong course that includes frequent relapses.

While Crohn’s disease can affect people of all ages, it is primarily a disease of young adults with onset typically before age 40 and will be a chronic disease throughout a patient’s life.  As a result, many Crohn’s disease patients will be required to have multiple imaging procedures throughout their lifetime.  Imaging plays an important role in the initial diagnosis of Crohn’s disease as well as the evaluation of symptomatic recurrence, which can provide valuable information on the presence, severity and extent of the disease.

Computed tomography (CT) is currently the most commonly used imaging technique for the noninvasive evaluation of complications associated with Crohn’s disease and for evaluating disease recurrence.  There is, however, mounting concern regarding a patient’s exposure to multiple doses of ionizing radiation, which is associated with CT and the long term adverse effects of such repeated exposure over a patient’s lifetime.

The potential risks from ionizing radiation exposure associated with CT have led to the development of MR techniques used for the evaluation of Crohn’s disease.  MR enterography is able to safely and noninvasively meet the imaging needs of patients with Crohn’s disease without exposing them to ionizing radiation.

MR enterography is an effective tool to evaluate and guide the treatment of patients with Crohn’s disease.  It is a noninvasive imaging technique that yields high contrast images of intestinal inflammation, abscesses and fistulas in the small bowel.  It utilizes dynamic image acquisition following the administration of intravenous contrast to provide information about the time course of bowel wall enhancement.  This serial imaging of bowel wall enhancement over time may help to distinguish active disease from inactive disease. Such dynamic imaging is not routinely performed with CT because of the radiation exposure associated with serial image acquisition.  As a result, MR enterography has been shown to be superior to CT for differentiating between acute and chronic inflammation in areas of the diseased bowel, which is critical for deciding on medical vs. surgical treatment.  Recent studies comparing CT enterography and MR enterography have demonstrated that both techniques are excellent at detecting features associated with Crohn’s disease and that the differences in sensitivity and specificity between the two techniques were not statistically significant.

MR enterography is an excellent and appropriate imaging option for patients with Crohn’s disease who are concerned about exposure to potentially harmful radiation. It is a particularly useful test for those patients who are younger, require frequent follow-up for symptom exacerbation and to monitor disease progression.

For more information on this important topic, please view this video commentary by a local radiologist, Dr. Jonathon Leipsic.