PMID- 33014546 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20201006 IS - 2156-7085 (Print) IS - 2156-7085 (Electronic) IS - 2156-7085 (Linking) VI - 11 IP - 7 DP - 2020 Jul 1 TI - Fiber photometry for monitoring cerebral oxygen saturation in freely-moving rodents. PG - 3491-3506 LID - 10.1364/BOE.393295 [doi] AB - Hemodynamic parameters, such as tissue oxygen saturation and blood volume fraction, are important markers of brain physiology. They are also widely used surrogate markers of electrophysiological activity. Here, we present a single fiber spectroscopic (SFS) system for monitoring cerebral oxygen saturation in localized, non-line-of-sight brain regions in freely-moving rodents. We adapted the implantation ferrule and patch cable design from commercialized optogenetics and fiber photometry systems, enabling stereotaxic fiber implantation, longitudinal tissue access and measurement from freely-moving animals. The optical system delivers and collects light from the brain through a 200 microm-core-diameter, 0.39NA multimode fiber. We robustly measured oxygen saturation from phantoms with different optical properties mimicking brain tissue. In mice, we demonstrated, for the first time, measurements of oxygen saturation from a highly-localized, targeted brain region over 31 days and continuous measurements from a freely-moving animal for over an hour. These results suggest that single fiber spectroscopy has enormous potential for functional brain monitoring and investigating neurovascular coupling in freely-moving animals. In addition, this technique can potentially be combined with fiber photometry systems to correct for hemodynamic artifacts in the fluorescence detection. CI - (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement. FAU - Yu, Linhui AU - Yu L AUID- ORCID: 0000-0001-6290-9867 AD - University of Calgary, Schulich School of Engineering, Electrical and Computer Engineering, Calgary, Canada. AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. FAU - Thurston, Elizabeth M S AU - Thurston EMS AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. AD - University of Calgary, Department of Neuroscience, Calgary, Canada. AD - These authors contributed equally to this work. FAU - Hashem, Mada AU - Hashem M AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. AD - University of Calgary, Biomedical Engineering Graduate Program, Calgary, Canada. AD - These authors contributed equally to this work. FAU - Dunn, Jeff F AU - Dunn JF AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. AD - University of Calgary, Biomedical Engineering Graduate Program, Calgary, Canada. FAU - Whelan, Patrick J AU - Whelan PJ AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. AD - University of Calgary, Department of Neuroscience, Calgary, Canada. FAU - Murari, Kartikeya AU - Murari K AD - University of Calgary, Schulich School of Engineering, Electrical and Computer Engineering, Calgary, Canada. AD - University of Calgary, Hotchkiss Brain Institute, Calgary, Canada. LA - eng PT - Journal Article DEP - 20200604 PL - United States TA - Biomed Opt Express JT - Biomedical optics express JID - 101540630 PMC - PMC7510909 COIS- The authors declare no conflicts of interest. EDAT- 2020/10/06 06:00 MHDA- 2020/10/06 06:01 PMCR- 2020/07/01 CRDT- 2020/10/05 06:19 PHST- 2020/03/25 00:00 [received] PHST- 2020/05/16 00:00 [revised] PHST- 2020/05/25 00:00 [accepted] PHST- 2020/10/05 06:19 [entrez] PHST- 2020/10/06 06:00 [pubmed] PHST- 2020/10/06 06:01 [medline] PHST- 2020/07/01 00:00 [pmc-release] AID - 393295 [pii] AID - 10.1364/BOE.393295 [doi] PST - epublish SO - Biomed Opt Express. 2020 Jun 4;11(7):3491-3506. doi: 10.1364/BOE.393295. eCollection 2020 Jul 1.