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Fredensborg FLH, Thilsing-Hansen K, Simonsen JA, Grupe P, Farahani ZA, Andersen CW, Gjedde A, Hvidsten S. Dynamic multi-pinhole collimated brain SPECT of Parkinson's disease by [ 123I]FP-CIT: a feasibility study of fSPECT. Sci Rep 2024; 14:6624. [PMID: 38503852 PMCID: PMC10951323 DOI: 10.1038/s41598-024-57152-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/13/2024] [Indexed: 03/21/2024] Open
Abstract
We investigated the feasibility of using a dopamine transporter (DaT) tracer ligand ([123I]FP-CIT) along with novel multi-pinhole brain collimators for dynamic brain single photon emission computed tomography (SPECT) in suspected Parkinson's disease patients. Thirteen patients underwent dynamic tracer acquisitions before standard imaging. Uptake values were corrected for partial volume effects. Specific binding ratio (SBRcalc) was calculated, reflecting binding potential relative to non-displaceable binding (BPND) in the cortex. Additional pharmacokinetic parameters (BPND, R1, k2) were estimated using the simplified reference tissue model, revealing differences between Kahraman low-score (LS) and high-score (HS) groups. Results showed increasing striatal tracer uptake until 100 min post-injection, with consistent values afterward. Uptake and SBRcalc ratios matched visual assessment. LS patients had lower putamen than caudate nucleus tracer uptake, decreased BPND values, while R1 and k2 values were comparable to HS patients. In conclusion, dynamic multi-pinhole SPECT using DaT tracer with the extraction of pharmacokinetic parameters is feasible and could help enable early differentiation of reduced and normal DaT values.
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Affiliation(s)
- Filip L H Fredensborg
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark.
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | | | - Jane A Simonsen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Peter Grupe
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Ziba A Farahani
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | | | - Albert Gjedde
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Translational Neuropsychiatry Unit, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- Department of Neurology and Neurosurgery, McGill University, Montréal, Québec, Canada
| | - Svend Hvidsten
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
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Simonsen JA, Thilsing-Hansen K, Høilund-Carlsen PF, Gerke O, Andersen TL. Glomerular filtration rate: comparison of simultaneous plasma clearance of 99mTc-DTPA and 51Cr-EDTA revisited. Scand J Clin Lab Invest 2020; 80:408-411. [PMID: 32362172 DOI: 10.1080/00365513.2020.1759138] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The issue of whether 99mTc-DTPA can replace 51Cr-EDTA for measurement of plasma clearance as a surrogate for glomerular filtration rate (GFR) is of great relevance to daily clinical practice. Prompted by the shortage of 51Cr-EDTA we conducted a head-to-head comparison in patients attending our department for GFR determination. The two tracers (3.7 MBq of 51Cr-EDTA and 8 MBq of 99mTc-DTPA) were administered intravenously immediately after each other, and the standard number of blood samples were drawn. Fifty-four patients were enrolled. In 51 of these, single-sample measurement was performed with the following results: GFREDTA was 84.6 ± 23.3 mL/min, GFRDTPA was 84.2 ± 24.7 mL/min. The mean difference was 0.4 ± 2.8 mL/min, p = 0.32, and results based on the two tracers were highly correlated (r = 0.995). GFRDTPA exceeded GFREDTA at high GFR values (difference < 0 at GFREDTA >91.4 mL/min) and vice versa (difference > 0 at GFREDTA < 91.4 mL/min). However, differences fell within few GFR units that most often will have no clinical consequence. We therefore conclude that 99mTc-DTPA can replace 51Cr-EDTA for single-sample determination of GFR in a clinical setting.
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Affiliation(s)
- Jane A Simonsen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | | | - Poul F Høilund-Carlsen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Oke Gerke
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Thomas L Andersen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
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Roberts AS, Chirumamilla M, Thilsing-Hansen K, Pedersen K, Bozhevolnyi SI. Near-infrared tailored thermal emission from wafer-scale continuous-film resonators. Opt Express 2015; 23:A1111-9. [PMID: 26406741 DOI: 10.1364/oe.23.0a1111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We experimentally investigate the near-infrared emission from simple-to-fabricate, continuous-film Fabry-Perot-type resonators, consisting only of unstructured dielectric and metallic films. We show that the proposed configuration is suitable for realization of narrowband emitters, tunable in ranges from mid- to near-infrared, and demonstrate emission centered at the wavelength of 1.7 μm, which corresponds to the band gap energy of GaSb-based photodetectors. The emission is measured at 748 K and follows well the emissivity as predicted from reflection measurements and Kirchhoff's reciprocity. The considered emitter configuration is spectrally highly tunable and, consisting of only few unstructured layers, is amenable to wafer-scale fabrication at low cost by use of standard deposition procedures.
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Leissner T, Lemke C, Jauernik S, Müller M, Fiutowski J, Tavares L, Thilsing-Hansen K, Kjelstrup-Hansen J, Magnussen O, Rubahn HG, Bauer M. Surface plasmon polariton propagation in organic nanofiber based plasmonic waveguides. Opt Express 2013; 21:8251-8260. [PMID: 23571915 DOI: 10.1364/oe.21.008251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Plasmonic wave packet propagation is monitored in dielectric-loaded surface plasmon polariton waveguides realized from para-hexaphenylene nanofibers deposited onto a 60 nm thick gold film. Using interferometric time resolved two-photon photoemission electron microscopy we are able to determine phase and group velocity of the surface plasmon polariton (SPP) waveguiding mode (0.967c and 0.85c at λ(Laser) = 812nm) as well as the effective propagation length (39 μm) along the fiber-gold interface. We furthermore observe that the propagation properties of the SPP waveguiding mode are governed by the cross section of the waveguide.
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Affiliation(s)
- Till Leissner
- University of Kiel, IEAP, Leibnizstr. 19, 24118 Kiel, Germany.
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Tavares L, Kjelstrup-Hansen J, Thilsing-Hansen K, Rubahn HG. Organic nanofibers integrated by transfer technique in field-effect transistor devices. Nanoscale Res Lett 2011; 6:319. [PMID: 21711821 PMCID: PMC3211406 DOI: 10.1186/1556-276x-6-319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 04/08/2011] [Indexed: 05/12/2023]
Abstract
The electrical properties of self-assembled organic crystalline nanofibers are studied by integrating these on field-effect transistor platforms using both top and bottom contact configurations. In the staggered geometries, where the nanofibers are sandwiched between the gate and the source-drain electrodes, a better electrical conduction is observed when compared to the coplanar geometry where the nanofibers are placed over the gate and the source-drain electrodes. Qualitatively different output characteristics were observed for top and bottom contact devices reflecting the significantly different contact resistances. Bottom contact devices are dominated by contact effects, while the top contact device characteristics are determined by the nanofiber bulk properties. It is found that the contact resistance is lower for crystalline nanofibers when compared to amorphous thin films. These results shed light on the charge injection and transport properties for such organic nanostructures and thus constitute a significant step forward toward a nanofiber-based light-emitting device.
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Affiliation(s)
- Luciana Tavares
- NanoSYD, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark
| | - Jakob Kjelstrup-Hansen
- NanoSYD, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark
| | - Kasper Thilsing-Hansen
- NanoSYD, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark
| | - Horst-Günter Rubahn
- NanoSYD, Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sønderborg, Denmark
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Kjelstrup-Hansen J, Liu X, Henrichsen HH, Thilsing-Hansen K, Rubahn HG. Conduction and electroluminescence from organic continuous and nanofiber thin films. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pssc.200983812] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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