Transcranial brain photoplethysmography to study the venules of cerebral cortex in patients with multiple sclerosis

Abstract

To evaluate the utility of a transcranial brain photoplethysmography parameter as a potential marker for patients with multiple sclerosis. We investigated 38 patients affected by multiple sclerosis, according to the revised McDonald criteria (12 males and 26 females, mean age 41.1 ± 8.5 years, Expanded Disability Status Scale mean value 2.6 ± 2.1) and compared them with 20 age- and sex-matched healthy controls. By means of transcranial brain photoplethysmography, a safe and non-invasive technology, we measured the increase in cerebral blood volume during compression for 10 s of the internal jugular veins of both sides in sitting position. The cerebral blood volume increase was significantly smaller in the multiple sclerosis patients (left frontal cortex: -58%, p < 0.0001; right frontal cortex: -59%, p < 0.0001) compared with the controls. Our study reveals that a minor increase in cerebral blood volume on the frontal cortex of both sides in sitting position is associated with a diagnosis of multiple sclerosis and might be a new marker.