The relationship between alterations in cerebral blood volume (CBV) and central chemosensitivity regulation was studied under neutral metabolic conditions and during metabolic acidosis. Fifteen healthy subjects (56±10 years) were investigated. To …
Interrogation of tissue with light offers the potential for noninvasive chemical measurement, and penetration with near-infrared wavelengths (750-1000 nm) is greater than with visible light. Specific absorption by clinically relevant compounds such …
Background and Purpose - Patients with orthostatic hypotension due to sympathetic failure become symptomatic when standing, although their capability to maintain cerebral blood flow is reported to be preserved. We tested the hypothesis that in …
Background and Purpose - With increasing age, assuming the upright position is more often accompanied by symptoms such as dizziness and lightheadedness, possibly as a result of a diminished oxygen supply to the brain due to impaired cerebral …
Near-infrared spectroscopy (NIRS) was used to assess human motor-cortex oxygenation changes in response to cyclic coupled movements of hand and foot. Using a highly sensitive NIRS instrument, we showed that it was possible to detect reproducible …
Five patients with chronic progressive external ophthalmoplegia (CPEO) and 27 healthy controls were examined by near-infrared spectroscopy (NIRS) for the noninvasive and direct quantitative measurement of muscle oxygen consumption and forearm blood …
In the past, the measurement of O2 consumption (Ȯ2) by the muscle could be carried out noninvasively by near-infrared spectroscopy from oxyhemoglobin and/or deoxyhemoglobin measurements only at rest or during steady isometric contractions. In the …
For a long time continuous wave near infrared instruments have been used to detect oxygenation changes in tissue. These instruments have proven to be reliable. The new generation of instruments, such as phase-modulated systems, or time-of-flight …
In the last four years near infrared spectroscopy (NIRS) has been used in cerebral functional activation studies to monitor changes in concentration of oxy-, deoxy- and total hemoglobin ([O 2 Hb], [HHb] and [tHb] respectively) in response to …