Techniques and Research
ROUTINE MRI SCANS
All MRI machines are capable of performing routine studies of the joints, spine and brain. At AIM our goal is to maximize detail that MRI can obtain by having thin slices. For example, our routine knee images are obtained at 3mm thin slices and our knee meniscus is obtained in 3D at 600micron ultra-thin slices. To learn more about the knee and our imaging view our knee gallery.
MS & CCSVI
Chronic Cerebrospinal Venous Insufficiency (CCSVI) remains a research based cause for Multiple Sclerosis (MS). At AIM we perform a complete contrast enhanced ‘traditional’ MS MRI study of the brain and cervical cord in addition to CCSVI research protocol. Currently in the medical literature, the cause and effect of CCVSI and MS remains uncertain. At AIM, we use the research based Siemen’s MRI protocol developed by Dr. Mark Haake to ensure consistency of MRI data analysis which includes SWI and Flow Quantification. Dr. Haacke’s imaging protocol and more information about MS and MRI can be found at MS-MRI.
SWI, a Siemens MRI sequence developed by Dr. Haake, is able to accurately determine iron or other heavy metal deposits in the brain. Researchers suspect iron build up occurs secondary to blocked or narrowed veins in the head or neck in MS patients. SWI is the only way to accurately visualize these iron deposits.
CCSVI is based on the hypothesis of an outflow (venous) irregularity in the head or neck. A blockage or reversed flow in a draining vein will cause a cerebrospinal vein flow rate change. The flow of the veins within the head can only be shown with Flow Quantification MRI or with Transcranial Ultrasound.
Flow Quantification MRI is able to determine which veins exhibit reduced or reversed flow. We assess the venous flow in multiple areas; including the upper and lower parts of both jugular veins, both transverse sinuses, the superior sagittal sinus and the straight sinus of the brain and/or regions demonstrating vascular narrowing. By assessing all of these structures, accurate blood flow results are obtained. Dr. Haacke recommends Flow Quantification MRI be performed as part of his imaging guidelines. There is also debate as to whether transcranial ultrasound can obtain similar results.
Ultrasound is limited by being highly “user dependent” and regular ultrasound cannot “see” through bone. Flow quantification MRI does not have this problem. In fact, it is equally easy to view the veins inside or outside the skull, neck or chest with Flow Quantification MRI.
A Transcranial Ultrasound machine has been developed to be able to see veins through the skull. As of July 1, 2010 there are no facilities in Vancouver with a transcranial ultrasound machine. A regular ultrasound will only be able to give information of the jugular veins in the neck after they exit the skull.
A definite diagnosis about CCSVI is ideally determined at Venography with pressure data. Research into this field is limited and imaging is still in its preliminary stages.
Presently no governing body in Canada endorses CCSVI Liberation as a treatment option; however, there is mounting evidence that may show promising for some patients. At AIM, we want to ensure the best quality study is preformed with objective flow criteria, to ensure reliable outcome data we feel that is best accomplished using the Haacke protocol with flow quantification before and after treatment.
While AIM doesn’t endorse liberation treatment, CCSVI patients are seeking these procedures at facilities outside of Canada. We and others recommend using MRI for screening and follow up using flow quantification. At AIM we have a research program for anybody who has had the liberation procedure to obtain objective flow quantification information thereby objectively determining if there is flow improvement after your procedure.
CCSVI FOLLOW-UP IMAGING
MS patients whom have undergone CCSVI liberation treament have the local convenience of Follow-Up Imaging at AIM Medical. CCSVI Follow-up Imaging entails an MR Neck Venogram and Flow Quantification MRI to determine vein flow, and if restenosis has occured. Additionally, we will image the brain to investigate if the number of lesions have changed. The entire imaging procedure will take approximately 30 minutes, and will follow with an immediate consultation with our on-site radiologist, whom will review your images with you and provide you with an instante update on your CCSVI status.
As per CCSVI screening, we will then provide you with a written final report and CD of your images. Copies are then forwarded to your general physician, specialists, and your CCSVI treatment facility on your behalf.
“We feel that flow quantification is very beneficial in preparation for treating our patients. It helps corroborate the significance of a stenosis. It may also help identify stenoses that may not be readily seen in 2 dimensions during the venogram. It provides us with evidence of reflux that will help lend credence to flow disturbance in the identified vessel. This of course, may help identify a significant stenosis and may also lend more weight to the significance of what may appear to be a passable stenosis on venography or the anatomic MRV images.
MRV flow quantification has some advantages over the ultrasound. It is operator independent for the most part. We see a very large variability in the quality and accuracy of ultrasound studies performed and sent to us. The MRV and flow quant studies however tend to be quite robust. In general most MRI’s we receive can be compared to an internal standard with a great degree of portability and cross-facility accuracy.” - Dr. J. Joseph Hewett MD, Pacific Interventionalists Inc, www.pacificInterventional.com
AIM COLLABORATES ON OBESITY AND LIPODYSTROPHY RESEARCH
Dr. William Gibson is a Clinical Geneticist with an interest in severe obesity and lipodystrophy. His group applies state-of-the-art assessment of body fat mass, fat distribution and circulating hormones to individuals with severe obesity and genetic lipodystrophy syndromes. The Gibson lab is pleased to be working with our team at AIM Medical Imaging to provide detailed assessment of fat distribution in rare genetic lipodystrophy disorders. Dr. Gibson combines this data with a detailed metabolic profile and targeted assessment of copy-number variants and specific rare nucleotide variants in an effort to discover the cause of the condition.
Ultimately, his goal is to design therapies for these poorly-understood disorders. The Gibson lab then hopes to translate these discoveries into viable treatments for prevention of obesity, type 2 diabetes and cardiovascular disease in people with rare disorders, and in the population as a whole.
Visit Dr. Gibson’s Lab Website.