A portable near infrared spectroscopy system for bedside monitoring of newborn brain

BACKGROUND: Newborns with critical health conditions are monitored in neonatal intensive care units (NICU). In NICU, one of the most important problems that they face is the risk of brain injury. There is a need for continuous monitoring of newborn's brain function to prevent any potential brain injury. This type of monitoring should not interfere with intensive care of the newborn. Therefore, it should be non-invasive and portable. METHODS: In this paper, a low-cost, battery operated, dual wavelength, continuous wave near infrared spectroscopy system for continuous bedside hemodynamic monitoring of neonatal brain is presented. The system has been designed to optimize SNR by optimizing the wavelength-multiplexing parameters with special emphasis on safety issues concerning burn injuries. SNR improvement by utilizing the entire dynamic range has been satisfied with modifications in analog circuitry. RESULTS AND CONCLUSION: As a result, a shot-limited SNR of 67 dB has been achieved for 10 Hz temporal resolution. The system can operate more than 30 hours without recharging when an off-the-shelf 1850 mAh-7.2 V battery is used. Laboratory tests with optical phantoms and preliminary data recorded in NICU demonstrate the potential of the system as a reliable clinical tool to be employed in the bedside regional monitoring of newborn brain metabolism under intensive care

Non-invasive neuroimaging: generalized linear models for interpreting functional near infrared spectroscopy signals

Proceedings of the 3rd International IEEE/EMBS Conference on Neural Engineering, 2007, pp. 461-464.Cognitive activity is related to important changes in the local blood flow level and in the oxygenation of the blood. These two effects lead to a modification of the optical properties of the cerebral cortex. With the aid of the functional Near InfraRed Spectroscopy (fNIRS) technique it is possible, through optical measures, to achieve information about the hemodynamic features of the brain activation. The aim of this study was to find a method to identify and to map the cerebral areas activated during a sustained attention task (Conner’s Continuous Performance Test – CPT) in a group of healthy subjects. This information will be of fundamental interest for a following study on a group of patients that will be administered the same examination. We propose a new analysis method based on the theory of Generalized Linear Model (GLM) in order to obtain intuitive cerebral activation maps during the performing of cognitive tasks