Time-resolved multi-channel optical system for assessment of brain oxygenation and perfusion by monitoring of diffuse reflectance and fluorescence

• Autorzy: Milej D. , Gerega A. , Kacprzak M. , Sawosz P. , Weigl W. , Maniewski R. , Liebert A.

Identyfikatory

DOI

10.2478/s11772-014-0178-y

• Języki publikacji: EN

Abstrakty

EN

Time-resolved near-infrared spectroscopy is an optical technique which can be applied in tissue oxygenation assessment. In the last decade this method is extensively tested as a potential clinical tool for noninvasive human brain function monitoring and imaging. In the present paper we show construction of an instrument which allows for: (i) estimation of changes in brain tissue oxygenation using two-wavelength spectroscopy approach and (ii) brain perfusion assessment with the use of single-wavelength reflectometry or fluorescence measurements combined with ICG-bolus tracking. A signal processing algorithm based on statistical moments of measured distributions of times of flight of photons is implemented. This data analysis method allows for separation of signals originating from extra- and intracerebral tissue compartments. In this paper we present compact and easily reconfigurable system which can be applied in different types of time-resolved experiments: two-wavelength measurements at 687 and 832 nm, single wavelength reflectance measurements at 760 nm (which is at maximum of ICG absorption spectrum) or fluorescence measurements with excitation at 760 nm. Details of the instrument construction and results of its technical tests are shown. Furthermore, results of in-vivo measurements obtained for various modes of operation of the system are presented.

Słowa kluczowe

EN

diffuse reflectance and fluorescence; time-resolved optical measurements; brain perfusion; brain oxygenation

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2014
• Tom: Vol. 22, No. 1
• Strony: 55--67
• Opis fizyczny: Bibliogr. 84 poz., rys., tab.

Twórcy

autor

Milej D.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

autor

Gerega A.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

autor

Kacprzak M.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

autor

Sawosz P.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

autor

Weigl W.

• Warsaw Praski Hospital, Department of Intensive Care and Anesthesiology, 67 Al. Solidarności Str., 03–401 Warsaw, Poland

autor

Maniewski R.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

autor

Liebert A.

• Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, 4 Ks. Trojdena Str., 02–109, Warsaw, Poland

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