Utveckling av en multikanal near infrared spectroscopy (NIRS) givare
(2011) EEM820 20111Department of Biomedical Engineering
- Abstract
- Near-Infrared Spectroscopy (NIRS) has become popular in many research fields for
the past two decades. NIRS technology uses near infrared light for measuring changes
in the concentration of deoxygenated hemoglobin and oxygenated hemoglobin. Noninvasive
near-infrared absorption measurements in tissue have many invaluable
applications in the medical field. Today NIRS is a very attractive technique within for
example brain research and studies of neurological and psychiatric diseases.
The purpose of this thesis is to develop a handheld, multi-channel, low cost and
compact Continuous Wave NIRS system. The system will non-invasively monitor
blood oxygenation and total hemoglobin level in the frontal lobe of the brain by
measuring... (More) - Near-Infrared Spectroscopy (NIRS) has become popular in many research fields for
the past two decades. NIRS technology uses near infrared light for measuring changes
in the concentration of deoxygenated hemoglobin and oxygenated hemoglobin. Noninvasive
near-infrared absorption measurements in tissue have many invaluable
applications in the medical field. Today NIRS is a very attractive technique within for
example brain research and studies of neurological and psychiatric diseases.
The purpose of this thesis is to develop a handheld, multi-channel, low cost and
compact Continuous Wave NIRS system. The system will non-invasively monitor
blood oxygenation and total hemoglobin level in the frontal lobe of the brain by
measuring changes in blood absorption with near-infrared light through tissue. With
LabView 8.6 the NIRS probe was programmed for data processing and thereafter was
analyzed data using MatLab 2007.
For building the NIRS system I utilized eight phototransistors with their own
PCBs (Printed Circuits Board), three LEDs (Light-Emitting Diode), one FPC
(Flexible Printed Circuit) and one computer board. Two wavelengths of 735nm and
850nm were considered due to the different optical properties of oxygenated and
deoxygenated hemoglobin at near-infrared region. This system can measure the
intensity of light scattering through the tissue and from this value and the absorption
coefficients of hemoglobin; the concentrations of the oxygenated and deoxygenated
hemoglobin (Hb and HbO2) can be calculated. The device's possible clinical
application, i.e., as a screening tool for the detection of sleep apnea, was explored
using the breath holding protocol. In persons with sleep apnea there is a reduction in
their oxy-hemoglobin saturation (O2 saturation) due to the cessation of airflow. This is
simulated using the breath holding protocol. With the prototype I built I was able to
show that the total hemoglobin concentration (in proportion to blood volume) within
the detected region increases during the breath holding period, reaches a peak after
the start of re-breathing, and gradually comes back to normal. The results obtained
proved that the device was able to detect the hemodynamic changes during the breath
holding tests.
This project has had many limitations mainly due to time-limit but despite this
the results are clear and show that the device works properly. The NIRS system is a
relatively new technique with many possibilities in the future but much research needs to be done and the knowledge about NIRS still has to be more widespread
before we will see it being used as a tool in the clinical medical field. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/2786718
- author
- Abdi, Aydin LU
- supervisor
- organization
- course
- EEM820 20111
- year
- 2011
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- Swedish
- additional info
- 2011-03
- id
- 2786718
- date added to LUP
- 2012-06-12 11:33:04
- date last changed
- 2014-10-08 14:47:03
@misc{2786718, abstract = {{Near-Infrared Spectroscopy (NIRS) has become popular in many research fields for the past two decades. NIRS technology uses near infrared light for measuring changes in the concentration of deoxygenated hemoglobin and oxygenated hemoglobin. Noninvasive near-infrared absorption measurements in tissue have many invaluable applications in the medical field. Today NIRS is a very attractive technique within for example brain research and studies of neurological and psychiatric diseases. The purpose of this thesis is to develop a handheld, multi-channel, low cost and compact Continuous Wave NIRS system. The system will non-invasively monitor blood oxygenation and total hemoglobin level in the frontal lobe of the brain by measuring changes in blood absorption with near-infrared light through tissue. With LabView 8.6 the NIRS probe was programmed for data processing and thereafter was analyzed data using MatLab 2007. For building the NIRS system I utilized eight phototransistors with their own PCBs (Printed Circuits Board), three LEDs (Light-Emitting Diode), one FPC (Flexible Printed Circuit) and one computer board. Two wavelengths of 735nm and 850nm were considered due to the different optical properties of oxygenated and deoxygenated hemoglobin at near-infrared region. This system can measure the intensity of light scattering through the tissue and from this value and the absorption coefficients of hemoglobin; the concentrations of the oxygenated and deoxygenated hemoglobin (Hb and HbO2) can be calculated. The device's possible clinical application, i.e., as a screening tool for the detection of sleep apnea, was explored using the breath holding protocol. In persons with sleep apnea there is a reduction in their oxy-hemoglobin saturation (O2 saturation) due to the cessation of airflow. This is simulated using the breath holding protocol. With the prototype I built I was able to show that the total hemoglobin concentration (in proportion to blood volume) within the detected region increases during the breath holding period, reaches a peak after the start of re-breathing, and gradually comes back to normal. The results obtained proved that the device was able to detect the hemodynamic changes during the breath holding tests. This project has had many limitations mainly due to time-limit but despite this the results are clear and show that the device works properly. The NIRS system is a relatively new technique with many possibilities in the future but much research needs to be done and the knowledge about NIRS still has to be more widespread before we will see it being used as a tool in the clinical medical field.}}, author = {{Abdi, Aydin}}, language = {{swe}}, note = {{Student Paper}}, title = {{Utveckling av en multikanal near infrared spectroscopy (NIRS) givare}}, year = {{2011}}, }