qNIRS: quantitative, multi-frequency near-infrared spectroscopy
Instructors: Stanislaw Wojtkiewicz
About this course
The minicourse is organized into three blocks: algorithms, hardware and data analysis, providing participants with a practical and integrated overview of quantitative near-infrared spectroscopy (qNIRS). The course is designed to connect theoretical principles with real-world measurement challenges and device implementation.
The algorithms block will introduce the principles of multi-frequency quantitative measurements. It will also cover device calibration strategies and discuss the advantages of calibration-free instrumentation for improving measurement usability.
The hardware block will present a new class of software-driven NIRS devices capable of multi-frequency domain measurements and high-density diffuse optical tomography in absolute units. Key engineering challenges will also be discussed, including instrumentation constraints, system design trade-offs, and the critical issue of the human-device interface.
The data analysis block will focus on in-vivo multi-frequency data examples and demonstrate how qNIRS can be used to image tissue haemodynamic properties.
Throughout the course, emphasis will be placed on how measurement theory, hardware limitations, and analytical assumptions interact in practice. Participants will also be guided through representative datasets and practical decision points in qNIRS acquisition and interpretation.
What will you learn?
Participants will learn:
- the principles of multi-frequency quantitative near infrared spectroscopy,
- the hardware foundations of qNIRS systems,
- practical approaches to collect gNIRS/fNIRS data,
- key challenges in translating theory into measurement practice,
- examples of in vivo data analysis for tissue haemodynamic imaging.
Participants will gain a practical understanding of how data acquisition, hardware design, and analytical expectations align in order to obtain reliable quantitative measurements.
Course details
Course duration
1 hours
Prerequisites and/or other notes
N/A
Delivery plan
45 minutes of presentation, followed by 15 minutes of questions and discussion:
15 min – introduction to qNIRS theory and principles of multi-frequency measurements
15 min – qNIRS hardware, instrumentation concepts and design challenges
15 min – application and analysis challenges: when practice meets theory
15 min – questions and discussion
Why should you enroll in this course?
This minicourse is intended for researchers and practitioners interested in fNIRS methods, optical instrumentation, and quantitative tissue imaging.
The goal of this minicourse is to introduce functional NIRS carried out in absolute units. This represents a significant shift in experimental design as quantitative measurements do not require a baseline or reference conditions. Instead, actual tissue haemodynamic parameters can be monitored instantaneously in absolute units.
In addition, the multi-frequency approach improves diffuse tomography as the light sensitivity depth varies with light modulation frequency. As a result, measurements carried out at different frequencies provide complementary information from different tissue depths.
The proposed minicourse is distinctive in combining algorithms, instrumentation, and practical data analysis in a unified introduction to qNIRS.