A novel device for non-invasive cerebral perfusion assessment

Currently brain perfusion can be assessed by the means of radio-invasive methods, such as single-photon emission computed tomography and positron emission tomography, or by hightech methods such as magnetic resonance imaging. These methods are known to be very expensive, with long examination time, and finally, cannot be used for assessing brain oxygen distribution in relation to exercise and/or cognition-tests. The near infrared spectroscopy (NIRS) is a non-invasive diagnostic technique. In real time it is capable of measuring tissue oxygenation using portable instrumentation with a relative low cost. We and other groups previously adopted this instrument for investigation of the oxygen consumption in the muscles at rest and during exercise. NIRS can be now used to assess brain perfusion through the intact skull in human subjects by detecting changes in blood hemoglobin concentrations. Changes in perfusion can be related to both arterial and venous problems. This novel equipment features allow for a wide field of innovative applications where portability, wearability, and a small footprint are essential. The present review shows how to use it in relation to exercise protocols of the upper and lower extremities, measured in healthy people and in conditions of arterial and chronic cerebro-spinal venous insufficiency.