Chronic cerebrospinal venous insufficiency is a theoretical hemodynamic condition which has been put forward as a possible cause of multiple sclerosis. Multiple sclerosis is a disease in which nerves degenerate over time, causing problems with muscles, movement, vision and sensation. The theory of chronic cerebrospinal venous insufficiency involves narrowing in the veins which drain blood from the brain and spinal cord. It has been suggested that pressure builds up in these abnormal veins, slowing the rate at which deoxygenated blood leaves the brain and leaving brain tissue low in oxygen. Blood may also flow back into the brain, and immune cells and red blood cells may leak out of veins into brain tissue, possibly causing or worsening multiple sclerosis.
In Italy in 2009, Dr. Paolo Zamboni put forward the theory that chronic cerebrospinal venous insufficiency (CCSVI) could contribute to damage seen in the nervous systems of patients with multiple sclerosis. He published the results of a pilot study that concluded that CCSVI was strongly associated with multiple sclerosis. Zamboni used ultrasound imaging to diagnose chronic cerebrospinal venous insufficiency, and this has continued to be the most frequently used method. During the diagnostic procedure, the veins that drain the brain and spinal cord are assessed for a number of abnormalities including narrowing, back flow of blood and lack of blood flow. One of Zamboni's research studies found that multiple sclerosis patients had a much higher proportion of these abnormalities compared with a healthy control group.
Other research which has been published has shown findings which conflict with Zamboni's results and there is controversy about chronic cerebrospinal venous insufficiency. In some studies no differences in blood flow were found between multiple sclerosis patients and the control group. Not all people with multiple sclerosis can be diagnosed as having CCSVI using the ultrasound technique. It is possible that the ultrasound procedure is not the best way to diagnose the condition, and an X-ray technique known as venography may be more suitable. Some researchers are not convinced that CCSVI represents a real condition.
A technique has been developed to treat chronic cerebrospinal venous insufficiency, in which the narrowed veins are widened by inflating special balloons inside them. This procedure is known as angioplasty. The aim of the treatment is to improve the symptoms of multiple sclerosis.
Although there have been some informal reports of positive results in multiple sclerosis patients following this type of surgery, much more research is needed to determine whether it represents an effective treatment. It has not yet been established that chronic cerebrospinal venous insufficiency is a real disorder, if it occurs more often in association with multiple sclerosis, and whether it is a cause of the disease. Future scientific research may provide answers.