| 1. |
- Farzam, Parisa, et al.
(author)
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Pre-clinical longitudinal monitoring of hemodynamic response to anti-vascular chemotherapy by hybrid diffuse optics
- 2017
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In: Biomedical Optics Express. - : OPTICAL SOC AMER. - 2156-7085. ; 8:5, s. 2563-2582
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Journal article (peer-reviewed)abstract
- The longitudinal effect of an anti-vascular endothelial growth factor receptor 2 (VEGFR-2) antibody (DC 101) therapy on a xenografted renal cell carcinoma (RCC) mouse model was monitored using hybrid diffuse optics. Two groups of immunosuppressed male nude mice (seven treated, seven controls) were measured. Tumor microvascular blood flow, total hemoglobin concentration and blood oxygenation were investigated as potential biomarkers for the monitoring of the effect of therapy twice a week and were related to the final treatment outcome. These hemodynamic biomarkers have shown a clear differentiation between two groups by day four. Moreover, we have observed that pre-treatment values and early changes in hemodynamics are highly correlated with the therapeutic outcome demonstrating the potential of diffuse optics to predict the therapy response at an early time point. (C) 2017 Optical Society of America
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| 2. |
- Han, Songfeng, et al.
(author)
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Non-contact scanning diffuse correlation tomography system for three-dimensional blood flow imaging in a murine bone graft model.
- 2015
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In: Biomedical Optics Express. - 2156-7085. ; 6:7
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Journal article (peer-reviewed)abstract
- A non-contact galvanometer-based optical scanning system for diffuse correlation tomography was developed for monitoring bone graft healing in a murine femur model. A linear image reconstruction algorithm for diffuse correlation tomography was tested using finite-element method based simulated data and experimental data from a femur or a tube suspended in a homogeneous liquid phantom. Finally, the non-contact system was utilized to monitor in vivo blood flow changes prior to and one week after bone graft transplantation within murine femurs. Localized blood flow changes were observed in three mice, demonstrating a potential for quantification of longitudinal blood flow associated with bone graft healing.
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| 3. |
- Johansson, Johannes D., et al.
(author)
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Optical investigation of antiangiogenic therapy in renal cell carcinoma
- 2015
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Conference paper (other academic/artistic)abstract
- Diffuse optical spectroscopy and diffuse correlation spectroscopy was used to monitor antiangiogenic therapy in renal cell carcinoma. The measurements allowed for hemodynamic characterization of the tumors and to monitor the initial antiangiogenic effect and relate it to final vessel density and tumor size.
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| 4. |
- Johansson, Johannes D., et al.
(author)
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Practical height correction for diffuse optical spectroscopy to account for curved tissue surfaces
- 2014
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In: Proceedings Biomedical optics 26-30 April 2014, Miami, Florida, United States. - : Optical Society of America. - 9781557529978
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Conference paper (other academic/artistic)abstract
- Non-contact broadband diffuse optical spectroscopy that is meant for longitudinal study of superficial tumor models suffers from systematic errors due to tissue surface. We propose a practical height correction algorithm to minimize these errors.
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| 5. |
- Johansson, Johannes D, et al.
(author)
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Scanning, non-contact, hybrid broadband diffuse optical spectroscopy and diffuse correlation spectroscopy system.
- 2016
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In: Biomedical Optics Express. - 2156-7085. ; 7:2, s. 481-498
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Journal article (peer-reviewed)abstract
- A scanning system for small animal imaging using non-contact, hybrid broadband diffuse optical spectroscopy (ncDOS) and diffuse correlation spectroscopy (ncDCS) is presented. The ncDOS uses a two-dimensional spectrophotometer retrieving broadband (610-900 nm) spectral information from up to fifty-seven source-detector distances between 2 and 5 mm. The ncDCS data is simultaneously acquired from four source-detector pairs. The sample is scanned in two dimensions while tracking variations in height. The system has been validated with liquid phantoms, demonstrated in vivo on a human fingertip during an arm cuff occlusion and on a group of mice with xenoimplanted renal cell carcinoma.
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| 6. |
- Lindner, Claus, et al.
(author)
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Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies.
- 2016
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:1
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Journal article (peer-reviewed)abstract
- The in vivo optical and hemodynamic properties of the healthy (n = 22) and pathological (n = 2) human thyroid tissue were measured non-invasively using a custom time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) system. Medical ultrasound was used to guide the placement of the hand-held hybrid optical probe. TRS measured the absorption and reduced scattering coefficients (μa, μs') at three wavelengths (690, 785 and 830 nm) to derive total hemoglobin concentration (THC) and oxygen saturation (StO2). DCS measured the microvascular blood flow index (BFI). Their dependencies on physiological and clinical parameters and positions along the thyroid were investigated and compared to the surrounding sternocleidomastoid muscle. The THC in the thyroid ranged from 131.9 μM to 144.8 μM, showing a 25-44% increase compared to the surrounding sternocleidomastoid muscle tissue. The blood flow was significantly higher in the thyroid (BFIthyroid = 16.0 × 10-9 cm2/s) compared to the muscle (BFImuscle = 7.8 × 10-9 cm2/s), while StO2 showed a small (StO2, muscle = 63.8% to StO2, thyroid = 68.4%), yet significant difference. Two case studies with thyroid nodules underwent the same measurement protocol prior to thyroidectomy. Their THC and BFI reached values around 226.5 μM and 62.8 × 10-9 cm2/s respectively showing a clear contrast to the nodule-free thyroid tissue as well as the general population. The initial characterization of the healthy and pathologic human thyroid tissue lays the ground work for the future investigation on the use of diffuse optics in thyroid cancer screening.
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| 7. |
- Lindner, Claus, et al.
(author)
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Diffuse optical characterization of the human thyroid
- 2016
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Conference paper (peer-reviewed)abstract
- The human thyroid was measured by ultrasound-guided near-infrared time-resolved spectroscopy and diffuse correlation spectroscopy characterizing the healthy thyroid and nodules allowing us to envision applications in thyroid cancer screening.
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| 8. |
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| 9. |
- Mireles, Miguel, et al.
(author)
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Non-invasive and quantitative in vivo monitoring of gold nanoparticle concentration and tissue hemodynamics by hybrid optical spectroscopies
- 2019
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In: Nanoscale. - : ROYAL SOC CHEMISTRY. - 2040-3364 .- 2040-3372. ; 11:12, s. 5595-5606
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Journal article (peer-reviewed)abstract
- Owing to their unique combination of chemical and physical properties, inorganic nanoparticles show a great deal of potential as suitable agents for early diagnostics and less invasive therapies. Yet, their translation to the clinic has been hindered, in part, by the lack of non-invasive methods to quantify their concentration in vivo while also assessing their effect on the tissue physiology. In this work, we demonstrate that diffuse optical techniques, employing near-infrared light, have the potential to address this need in the case of gold nanoparticles which support localized surface plasmons. An orthoxenograft mouse model of clear cell renal cell carcinoma was non-invasively assessed by diffuse reflectance and correlation spectroscopies before and over several days following a single intravenous tail vein injection of polyethylene glycol-coated gold nanorods (AuNRs-PEG). Our platform enables to resolve the kinetics of the AuNR-PEG uptake by the tumor in quantitative agreement with ex vivo inductively coupled plasma mass spectroscopy. Furthermore, it allows for the simultaneous monitoring of local tissue hemodynamics, enabling us to conclude that AuNRs-PEG do not significantly alter the animal physiology. We note that the penetration depth of this current probe was a few millimeters but can readily be extended to centimeters, hence gaining clinical relevance. This study and the methodology presented here complement the nanomedicine toolbox by providing a flexible platform, extendable to other absorbing agents that can potentially be translated to human trials.
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| 10. |
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