Magnetic resonance imaging shows that reduced brain blood flow that may be caused by blockages in the veins is not limited or specific to multiple sclerosis, according to a study published online in the journal Radiology. This indicates that the blockage, known as chronic cerebrospinal venous insufficiency (CCSVI), is likely an accessory process to MS and not necessarily related to the disease.
Recent research suggested a strong correlation between CCSVI and MS, which has led to the development of controversial treatments that involve placing stents in veins leading from the brain. To clarify the issue, Simone Marziali, MD, and colleagues from the University of Rome in Italy investigated the relationship between CCSVI and MS, using dynamic susceptibility contrast-enhanced (DSC) MRI, which offers more accurate assessment of brain flow than that of color-Doppler-ultrasounds (CDU). DSC MR imaging is a more accurate test to assess brain blood flow than is CDU, and the two were used to assess two different anatomical structures.
Thirty-nine patients with MS and 26 healthy controls participated in the study. The patients with MS had tested positive for CCSVI by CDU.
The researchers found that the CCSVI-positive patients did show decreased blood flow and volume compared with the controls, but there was no significant interaction between the MS and the CCSVI for any of the blood flow parameters. There was also no correlation between the cerebral blood flow and volume in the brain’s white matter and the severity of disability among the patients.
“This study clearly demonstrates the important role of MRI in defining and understanding the causes of MS,” said Marziali. “I believe that, in the future, it will be necessary to use powerful and advance diagnostic tools to obtain a better understanding of this and other diseases still under study.”