Coherent Hemodynamics Spectroscopy - a non-invasive and real-time diagnostic technology to identify and monitor brain damage


Non-invasive and real-time optical diagnostic technology that offers new way to identify and monitor brain damage resulting from traumatic injury, stroke or vascular dementia.


Cerebrovascular diseases are the second leading cause of death and dementia, and the leading cause of disability worldwide. More accurate measurements of the concentration and oxygen saturation of hemoglobin in brain tissue will improve efforts in early detection of cerebral ischaemia, vascular cognitive impairment, assessment of recovery from strokes, and functional brain studies. The medical diagnosis of brain disorders can be difficult due to the sensitivity of brain tissue to invasive medical probes and there is a significant need for non-invasive diagnosis and monitoring.



This hemodynamic perturbation model treats the complex microvasculature as a whole, without making assumptions about its detailed architecture, and without introducing a large number of parameters to describe it.  Thus, an advantageous compromise is made, sufficiently describing the complexity of the microvasculature while making use of a limited number of free parameters. The hemodynamic perturbation model utilizes a new frequency-resolved measurement scheme that opens up a new technical avenue that may find numerous applications in the design of new instrumental techniques and in a number of research areas. The hemodynamic perturbation model is capable of predicting data representative of localized cerebral autoregulation which is an improvement over conventional methods. Conventional cerebral autoregulation measurement systems rely on inferring data representative of global cerebral autoregulation based on a systemic measurement of arterial blood pressure and a global cerebral measurement of blood flow.


Coherent hemodynamics spectroscopy (CHS) measures blood flow, blood volume, and oxygen consumption in the brain. It uses near infrared (NIR) light technology to scan brain tissue, and then applies mathematical algorithms to interpret that information.  The researchers have developed a novel quantitative hemodynamic model which can relate physiological perturbations in cerebral blood volume, blood flow, and oxygen consumption to the associated hemodynamic effects that are measurable with functional near-infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI). CHS in conjunction with the new hemodynamic model, is capable of assessing cerebral hemodynamics integrity and localized cerebral autoregulation.


CHS has been demonstrated on a group of healthy human subjects, validating its feasibility and ability to provide measures of local cerebral autoregulation. The quantitative hemodynamic model has been validated on fNIRS and fMRI data reported in the literature to demonstrate its accuracy at relating measured fNIRS and fMRI signals with the associated perturbations in CBV, CBF, and CMRO2.


Published in Canada, Europe and the United States


Licensing Contact

Chiara Vannucci