Background: Searching for clues about CCSVI and MS in the younger population
Often considered a disease which affects adolescents, multiple sclerosis (MS) has been observed in a small percentage of children. Diagnosed before reaching their teenage years, children with MS experience symptoms of a relapsing-remitting course, characterized by defined attacks (relapses) followed by periods of remission. Symptoms of MS are similar in both children and adults; however certain symptoms such as irritability and low-grade fever can be experienced more frequently in children.
Children with MS can provide a lot of information on the cause and course of the disease, simply because they are younger and can be observed carefully for initial signs that cannot be examined in an adult with MS. Every day, researchers are learning more about MS from pediatric studies, allowing them to zero in on ways to treat and prevent it. They note that if chronic cerebrospinal venous insufficiency (CCSVI) is a causative factor for MS, it should be evident even in the youngest MS population. As well, children with MS provide an opportunity to rule out disability and age-related health conditions as possible factors affecting the prevalence of CCSVI in people with MS.
In June 2010, the National MS Society (USA) and the MS Society of Canada committed over $2.4 million to support seven new research projects that would gain further insight into the relationship between CCSVI and MS. One of the studies is led by Dr. Brenda Banwell, who previously served as the Director of the Pediatric MS Clinic at the Hospital for Sick Children (SickKids) in Toronto and went on to join the Children's Hospital of Philadelphia as the new chief of Neurology.
To further examine the role of CCSVI in the pediatric MS population, Dr. Banwell assembled a team of pediatric brain imaging experts and neurologists who observed vein abnormalities in children and teenagers with MS, and compared what they found to healthy individuals of the same age. Preliminary results from the study, published last month in the American Journal of Neuroradiology, did not identify CCSVI as a key feature of pediatric MS.
The study:
Twenty-six children with MS (aged 18 years or younger), 26 age-matched healthy children, and 13 individuals with pediatric-onset MS (initially diagnosed as pediatric MS but are now adults) underwent ultrasound of the veins in the head and neck. The pediatric ultrasound technologists and pediatric radiologists who assessed the ultrasound data for signs of CCSVI were blinded to participant status. In addition, advanced MRI techniques were performed in the pediatric MS and non-MS groups to look for any irregularities in vein structure and blood flow.
The ultrasound technologists and pediatric radiologists
attended a one week Cerebral Venous Function and Anomaly Program
directed by Dr. Robert Zivadinov in the Buffalo Neuroimaging
Analysis Center at State University of New York. The program
included instruction, demonstration and hands on training in
cerebrospinal venous scanning using similar ultrasound methods
previously outlined by Dr. Zamboni.
Results:
Fifty participants (73.5%) had normal ultrasound findings, 15
(23.1%) met 1 criterion for CCSVI, and 2 children with MS and 1
young adult with pediatric-onset MS met more than 1 criteria for
CCSVI. Statistical analysis of the data pointed to no association
between CCSVI and MS in the pediatric population.
Demographic and disease characteristics did not differ between
children with MS who displayed signs of CCSVI and those children
with MS who did not display signs of CCSVI. Imaging measures of
blood flow in the brain did not differ between the 2 children
with MS who displayed signs of CCSVI and healthy controls; no
child demonstrated venous obstruction. Evaluation of venous
anatomy and blood flow rates indicate that venous outflow is
intact in children with MS.
Overall the findings of the study argue against CCSVI as a
causative factor for MS.
Comment:
Results from the study add to the growing body of information on CCSVI and MS. Researchers emphasize that pediatric studies are critical in determining the early triggers of MS that are unaffected by enhanced age and disability. Ultrasound and MRI data collected by Dr. Banwell and colleagues show minimal signs of CCSVI in children with MS. The MS Society shares in the disappointment many Canadians have about these and similar emerging results and are aware that people with MS want more information about CCSVI. Results from ongoing research studies can offer us more definitive answers and will be continually monitored by the organization.
Sources:
Laughlin S et al. No Evidence for Impairment of Venous
Hemodynamics in Children or Young Adults with Pediatric-Onset
Multiple Sclerosis. American Journal of Neuroradiology 18 July 2013
[Epub ahead of print]