Name: Evaluations of Oxygenation and Vascular Perfusion in Pre-Clinical Models of Cancer and Wound Healing Using OS-DCE OAI (Video) | JoVE Journal
Uploaded: 2026-04-07T13:00:00.000+00:00
Duration: 8 min 13 s
Description: Learn a unified OS-DCE OAI protocol for simultaneous assessment of oxygenation and vascular perfusion in orthotopic breast cancer tumors and cutaneous wounds using mouse models. This noninvasive method enables early detection of physiological changes.

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The authors would like to thank Dr. Neal Burton at iThera Medical, GmbH, for consultation. This work was funded by UW-Madison Radiology NRSA grant (2T32CA009206-46), ITPT Radiological Sciences Trainee Pilot Grant, Clinical and Translational Science Award (CTSA) program, the National Center for Advancing Translational Sciences (NCATS), grant UL1TR002373 and TL1TR002375, NIH R43 CA265603, NIH R01 EB034261, NIH R21 EB037731, and a Falk Catalyst Award from the Falk Medical Research Trust.

<ol><li>Wang, L. V., Hu, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Photoacoustic+tomography%3A+In+vivo+imaging+from+organelles+to+organs%5BTitle%5D)+AND+%22Science%22%5BJournal%5D)">Photoacoustic tomography: In vivo imaging from organelles to organs.</a> Science. 335 (6075), 1458-1462 (2012).</li>
<li>Ntziachristos, V., Razansky, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Molecular+imaging+by+means+of+multispectral+optoacoustic+tomography+%28MSOT%29%5BTitle%5D)+AND+%22Chem+Rev%22%5BJournal%5D)">Molecular imaging by means of multispectral optoacoustic tomography (MSOT).</a> Chem Rev. 110 (5), 2783-2794 (2010).</li>
<li>Sourbron, S. P., Buckley, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Classic+models+for+dynamic+contrast-enhanced+MRI%5BTitle%5D)+AND+%22NMR+Biomed%22%5BJournal%5D)">Classic models for dynamic contrast-enhanced MRI.</a> NMR Biomed. 26 (8), 1004-1027 (2013).</li>
<li>Hupple, C. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+light-fluence-independent+method+for+the+quantitative+analysis+of+dynamic+contrast-enhanced+multispectral+optoacoustic+tomography+%28DCE+MSOT%29%5BTitle%5D)+AND+%22Photoacoustics%22%5BJournal%5D)">A light-fluence-independent method for the quantitative analysis of dynamic contrast-enhanced multispectral optoacoustic tomography (DCE MSOT).</a> Photoacoustics. 10, 54-64 (2018).</li>
<li>Xiao, T. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Applying+dynamic+contrast-enhanced+MSOT+imaging+to+intratumoral+pharmacokinetic+modeling%5BTitle%5D)+AND+%22Photoacoustics%22%5BJournal%5D)">Applying dynamic contrast-enhanced MSOT imaging to intratumoral pharmacokinetic modeling.</a> Photoacoustics. 11, 28-35 (2018).</li>
<li>Han, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Dynamic+2-deoxy-D-glucose-enhanced+multispectral+optoacoustic+tomography+for+assessing+metabolism+and+vascular+hemodynamics+of+breast+cancer%5BTitle%5D)+AND+%22Photoacoustics%22%5BJournal%5D)">Dynamic 2-deoxy-D-glucose-enhanced multispectral optoacoustic tomography for assessing metabolism and vascular hemodynamics of breast cancer.</a> Photoacoustics. 32, 100531(2023).</li>
<li>Pickles, M. D., Manton, D. J., Lowry, M., Turnbull, L. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prognostic+value+of+pre-treatment+DCE-MRI+parameters+in+predicting+disease-free+and+overall+survival+for+breast+cancer+patients+undergoing+neoadjuvant+therapy%5BTitle%5D)+AND+%22Eur+J+Radiol%22%5BJournal%5D)">Prognostic value of pre-treatment DCE-MRI parameters in predicting disease-free and overall survival for breast cancer patients undergoing neoadjuvant therapy.</a> Eur J Radiol. 71 (3), 498-505 (2009).</li>
<li>Goel, S., et al. Evaluations of radiotherapy in small animal models of pancreatic cancer with oxygen-enhanced–dynamic contrast-enhanced multispectral optoacoustic tomography (OE-DCE MSOT). Photons Plus Ultrasound: Imaging and Sensing 2023, 12379, (2023).</li>
<li>Yang, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Evaluations+of+a+cutaneous+wound+healing+model+using+oxygen-enhanced+dynamic+contrast-enhanced+photoacoustic+imaging+%28OE-DCE+PAI%29%5BTitle%5D)+AND+%22Mol+Imaging+Biol%22%5BJournal%5D)">Evaluations of a cutaneous wound healing model using oxygen-enhanced dynamic contrast-enhanced photoacoustic imaging (OE-DCE PAI).</a> Mol Imaging Biol. 26 (6), 995-1004 (2024).</li>
<li>Longo, D. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Water-soluble+melanin+derivatives+for+dynamic+contrast-enhanced+photoacoustic+imaging+of+tumor+vasculature+and+response+to+antiangiogenic+therapy%5BTitle%5D)+AND+%22Adv+Healthcare+Mater%22%5BJournal%5D)">Water-soluble melanin derivatives for dynamic contrast-enhanced photoacoustic imaging of tumor vasculature and response to antiangiogenic therapy.</a> Adv Healthcare Mater. 6 (1), 1600550(2017).</li>
<li>Ermolayev, V., Dean-Ben, X. L., Mandal, S., Ntziachristos, V., Razansky, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Simultaneous+visualization+of+tumour+oxygenation%2C+neovascularization+and+contrast+agent+perfusion+by+real-time+three-dimensional+optoacoustic+tomography%5BTitle%5D)+AND+%22Molec+Imaging%22%5BJournal%5D)">Simultaneous visualization of tumour oxygenation, neovascularization and contrast agent perfusion by real-time three-dimensional optoacoustic tomography.</a> Molec Imaging. 26, 1843-1851 (2016).</li>
<li>Chen, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Concurrent+fluorescence+and+volumetric+optoacoustic+tomography+of+nanoagent+perfusion+and+bio-distribution+in+solid+tumors%5BTitle%5D)+AND+%22Biomed+Opt+Express%22%5BJournal%5D)">Concurrent fluorescence and volumetric optoacoustic tomography of nanoagent perfusion and bio-distribution in solid tumors.</a> Biomed Opt Express. 10 (10), 5093-5102 (2019).</li>
<li>Taruttis, A., Morscher, S., Burton, N. C., Razansky, D., Ntziachristos, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Fast+multispectral+optoacoustic+tomography+%28MSOT%29+for+dynamic+imaging+of+pharmacokinetics+and+biodistribution+in+multiple+organs%5BTitle%5D)+AND+%22PLoS+One%22%5BJournal%5D)">Fast multispectral optoacoustic tomography (MSOT) for dynamic imaging of pharmacokinetics and biodistribution in multiple organs.</a> PLoS One. 7 (1), e30491(2012).</li>
<li>Tomaszewski, M. R., Gehrung, M., Joseph, J., Quiros-Gonzalez, I., Disselhorst, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Oxygen-enhanced+and+dynamic+contrast-enhanced+optoacoustic+tomography+provide+surrogate+biomarkers+of+tumor+vascular+function%2C+hypoxia%2C+and+necrosis%5BTitle%5D)+AND+%22Cancer+Res%22%5BJournal%5D)">Oxygen-enhanced and dynamic contrast-enhanced optoacoustic tomography provide surrogate biomarkers of tumor vascular function, hypoxia, and necrosis.</a> Cancer Res. 78 (20), 5980-5991 (2018).</li>
<li>Choi, W., Park, B., Choi, S., Oh, D., Kim, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Recent+advances+in+contrast-enhanced+photoacoustic+imaging%3A+and+practical+challenges%5BTitle%5D)+AND+%22Chem+Rev%22%5BJournal%5D)">Recent advances in contrast-enhanced photoacoustic imaging: and practical challenges.</a> Chem Rev. 123 (11), 7379-7419 (2023).</li>
<li>Weber, J., Beard, P. C., Bohndiek, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Contrast+agents+for+molecular+photoacoustic+imaging%5BTitle%5D)+AND+%22Nat+Methods%22%5BJournal%5D)">Contrast agents for molecular photoacoustic imaging.</a> Nat Methods. 13 (8), 639-650 (2016).</li>
<li>Fu, Q. R., Zhu, R., Song, J. B., Yang, H. H., Chen, X. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Photoacoustic+imaging%3A+Contrast+agents+and+their+biomedical+applications%5BTitle%5D)+AND+%22Adv+Materials%22%5BJournal%5D)">Photoacoustic imaging: Contrast agents and their biomedical applications.</a> Adv Materials. 31 (6), 1805875(2019).</li>
<li>Nair, A. B., Jacob, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+simple+practice+guide+for+dose+conversion+between+animals+and+human%5BTitle%5D)+AND+%22J+Basic+Clin+Pharm%22%5BJournal%5D)">A simple practice guide for dose conversion between animals and human.</a> J Basic Clin Pharm. 7 (2), 27-31 (2016).</li>
<li>Alander, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+review+of+indocyanine+green+fluorescent+imaging+in+surgery%5BTitle%5D)+AND+%22Int+J+Biomed+Imaging%22%5BJournal%5D)">A review of indocyanine green fluorescent imaging in surgery.</a> Int J Biomed Imaging. 2012, 940585(2012).</li>
<li>Xia, J., Chen, W. Y., Maslov, K., Anastasio, M. A., Wang, L. H. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Retrospective+respiration-gated+whole-body+photoacoustic+computed+tomography+of+mice%5BTitle%5D)+AND+%22J+Biomed+Opt%22%5BJournal%5D)">Retrospective respiration-gated whole-body photoacoustic computed tomography of mice.</a> J Biomed Opt. 19 (1), 016003(2014).</li>
<li>Liu, S., Wang, T., Zheng, X., Zhu, Y., Tian, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((On+the+imaging+depth+limit+of+photoacoustic+tomography+in+the+visible+and+first+near-infrared+windows%5BTitle%5D)+AND+%22Optics+Express%22%5BJournal%5D)">On the imaging depth limit of photoacoustic tomography in the visible and first near-infrared windows.</a> Optics Express. 32 (1), 5460-5480 (2024).</li>
<li>Oraevsky, A., Clingman, B., Zalev, J., Stavros, A., Yang, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Clinical+optoacoustic+imaging+combined+with+ultrasound+for+coregistered+functional+and+anatomical+mapping+of+breast+tumors%5BTitle%5D)+AND+%22Photoacoustics%22%5BJournal%5D)">Clinical optoacoustic imaging combined with ultrasound for coregistered functional and anatomical mapping of breast tumors.</a> Photoacoustics. 12, 30-45 (2018).</li>
<li>Cox, B., Laufer, J. G., Arridge, S. R., Beard, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Quantitative+spectroscopic+photoacoustic+imaging%3A+a+review%5BTitle%5D)+AND+%22J+Biomed+Opt%22%5BJournal%5D)">Quantitative spectroscopic photoacoustic imaging: a review.</a> J Biomed Opt. 17 (6), 061202(2012).</li>
<li>Khodaverdi, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Two+photoacoustic+spectral+coloring+compensation+techniques+adapted+to+the+context+of+human+in-vivo+oxygenation+measurements%5BTitle%5D)+AND+%22Biomed+Optics+Express%22%5BJournal%5D)">Two photoacoustic spectral coloring compensation techniques adapted to the context of human in-vivo oxygenation measurements.</a> Biomed Optics Express. 16 (6), 2217-2231 (2025).</li>
<li>Reinhart, M. B., Huntington, C. R., Blair, L. J., Heniford, B. T., Augenstein, V. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Indocyanine+green%3A+Historical+context%2C+current+applications%2C+and+future+considerations%5BTitle%5D)+AND+%22Surg+Innov%22%5BJournal%5D)">Indocyanine green: Historical context, current applications, and future considerations.</a> Surg Innov. 23 (2), 166-175 (2016).</li>
</ol>

The authors have no conflicts of interest with regard to this work.

DCE OAI PK curves may be affected by a variety of artifacts that reduce the reliability of PK analysis. One common pitfall is the presence of superficial wounds, scabs, or dried blood within the imaging field, which can introduce strong, non-specific absorption at the skin surface and obscure deeper signals (Figure 8). When drawing ROIs within the tumor, care should be taken to avoid including these superficial structures to ensure that the extracted curves reflect intratumoral contrast dyna...

Optoacoustic imaging (OAI), also referred to as photoacoustic imaging or multispectral optoacoustic tomography, is a relatively new modality that couples optical excitation with ultrasound (US) detection to enable deep tissue imaging1,2. In OAI, brief nanosecond laser pulses excite endogenous chromophores such as oxy- and deoxyhemoglobin, producing localized thermoelastic expansion and wideband acoustic waves that are detected by US transducers. These signals enable OAI to yield images with optical contrast at ultrasound-like spatial resolution while achieving centimeter-scale depth of view in vivo. When data are acquired at multiple wavelengths and analyzed with spectral unmixing, Oxygen Sensitive (OS) OAI can estimate relative concentrations of oxy- and deoxyhemoglobin and thereby infer tissue oxygen saturation (%sO&#8322;)2. Blood oxygen saturation provides a functional evaluation of microvascular physiology that is difficult to access noninvasively with other methods.
Vascular perfusion is also useful for evaluations of microvascular physiology. Vascular perfusion represents a combination of vascular flow, permeability, and vessel surface area3. To quantify perfusion, OAI can be used with an exogenous contrast agent to perform Dynamic Contrast Enhanced OAI (DCE OAI). In this approach, temporal imaging before, during, and after contrast agent injection monitors the pharmacokinetics (PK) of the agent. These results can be modeled to measure the wash-in rate (NKtrans) from the blood plasma compartment to the tumor extracellular extravascular compartment, and washout rate (kep) from the tumor extracellular extravascular compartment to the plasma compartment. We have developed a PK modeling method that avoids the notorious problem of light fluence (i.e., scattering and absorbance in tissues that cause variable radiant energy through the tissue)4. Our method normalizes the change in dynamic OAI signal from 0% (pre-injection) to 100% (maximum enhancement) and then uses differential equations to estimate NKtrans wash-in rate and the kep. Other DCE OAI studies have used standard PK modeling methods that suffer from the major assumption that light fluence is uniform throughout the tissue5,6.
DCE OAI results can also be used to assess wash-in rates by making empirical measurements of Maximum Signal Enhancement (MSE), Time-to-Peak (TTP) to reach MSE, slope (typically for injection to TTP), and Initial Area Under the Curve (IAUC; again typically for injection to TTP post-injection)7. It should be noted that if the TTP occurs later in the PK curve, the slope or IAUC can be taken during the linear portion of the curve or from the time of injection to 1 min post-injection. We have shown that empirical measurements can also be useful when evaluating treatments administered to tumor models or when evaluating wound healing8,9. Other studies have also shown value in using empirical measurements to evaluate tumor vascular permeability and liver fibrosis10,11. The shape of the PK curve can also be used to qualitatively categorize tumor vascular perfusion as high or low12,13,14.
In addition, the OAI signal at a single post-injection time point can be used as an empirical evaluation of perfusion, known as non-dynamic Contrast Enhanced OAI (CE OAI)15. A CE OA image that shows a bright tumor or wound is simplistic and highly visual and yet is often only used for a qualitative assessment of high vs. low perfusion. In general, the dynamic change in OAI signals after TTP is not analyzed to empirically evaluate vascular perfusion in tumors. However, as shown below, the wash-in rates in wounds are extremely fast, so that NKtrans, TTP, slope, and IAUC are challenging to measure. Therefore, we have used the linear or exponential slope of the washout phase as an empirical measure of vascular perfusion in wounds9.
Most OAI agents absorb in the near-infrared (NIR) wavelength range, which can penetrate deeper into tissues16,17. However, water absorption at wavelengths greater than 900 nm limits the usable in vivo OAI wavelength range to 700&#8211;900 nm for most applications2. Indocyanine green (ICG) is a prototypical DCE OAI agent because it offers strong NIR absorption at 780&#8211;800 nm, produces a moderately strong OAI signal, and has favorable biocompatibility with FDA approval for clinical use. These features enable intravascular contrast and interpretable PK curves.
We have developed a combined OS-DCE OAI protocol to evaluate oxygenation and vascular perfusion in pre-clinical models of solid tumors and wounds8,9. The OS portion of this protocol can evaluate oxygenation in multiple imaging slices that can cover entire tumor and wound volumes in mouse models. The DCE portion of our protocol has an option to image a single slice of the tumor or wound using multiple laser wavelengths (improving the accuracy of contrast agent detection), or to image as many as 5 slices with a single laser wavelength (improving spatial coverage). We have used OS-DCE OAI to monitor the change in oxygenation and vascular perfusion after treating a tumor model with radiotherapy or with combretastatin A4 phosphate, a vascular disrupting agent4,8. We have also used OS-DCE OAI to monitor wound healing9. DCE OAI gives OAI the ability to monitor progression via vascular perfusion that can be applied to a variety of diseases.

<table><tbody><tr><td>20 G Needle</td><td>Exel INT</td><td>26417</td><td>Hypodermic needle; 20G x 1&quot;, used for preparing heparin solutions</td></tr><tr><td>4T1 cells</td><td>ATCC</td><td>CRL-2539</td><td>Triple negative breast cancer cell line</td></tr><tr><td>Anti-Anti (100x)</td><td>Gibco</td><td>15240-062</td><td>Antibiotic cocktail</td></tr><tr><td>Biopsy punch</td><td>Integra&amp;nbsp;</td><td>33-36</td><td>6 mm disposable biopsy punch&amp;nbsp;</td></tr><tr><td>Cell Culture Grade Water</td><td>Corning</td><td>25-055-CV</td><td>500 mL; tested to USP sterile sater for inection specifications&amp;nbsp;</td></tr><tr><td>Collagen Matrix Solution</td><td>Corning</td><td>354262</td><td>Collagen matrix for tumor fomation and injection</td></tr><tr><td>Ethanol</td><td>Deacon Laboratory</td><td>2701</td><td>General purpose antiseptic</td></tr><tr><td>Eye Lube&amp;nbsp;</td><td>Optixcare&amp;nbsp;</td><td>50-218-8442</td><td>20 g/.70 oz; for animal use only&amp;nbsp;</td></tr><tr><td>Gauze&amp;nbsp;</td><td>Fisherbrand</td><td>22-415-468</td><td>Cotton gauze pad; 3&quot; x 3&quot; (7.6 x 7.6 cm); 12-Ply</td></tr><tr><td>Gloves</td><td>VWR</td><td>76457-130</td><td>Nitrile examination gloves</td></tr><tr><td>Heparin</td><td>Meitheal</td><td>NDC71288-402-10</td><td>10,000 USP units per 10 mL, 1000 USP units per mL; 10 mL Multi-Dose Vial</td></tr><tr><td>Indocyanine green</td><td>TCI</td><td>I0535</td><td>Optoacoustic Contrast Agent</td></tr><tr><td>Isoflurane</td><td>Isospire</td><td>17033-091-25</td><td>A nonflammable, nonexplosive inhalation anesthetic for use in horses and dogs; 250 mL&amp;nbsp;</td></tr><tr><td>Laboratory Film</td><td>Parafilm&amp;nbsp;</td><td>PM-992</td><td>2&quot; x 250&#039;; 1&quot; diameter core</td></tr><tr><td>Nair body bream Hair remover&amp;nbsp;</td><td>Nair</td><td>LL4038</td><td>Depiliatory Cream; rich cocoa butter &amp;amp; vitamin E</td></tr><tr><td>Needle&amp;nbsp;</td><td>Terumo</td><td>NN2732R</td><td>27G x 1 1/4&quot; (6.40 mm x 32 mm); R.W. Reg. Bevel&amp;nbsp;</td></tr><tr><td>Optoacoustic Imaging Machine</td><td>iTheraMedical&amp;nbsp;</td><td>MSOT inVision 512</td><td>Optoacoustic scanner</td></tr><tr><td>PBS, 1x</td><td>Corning&amp;nbsp;</td><td>21-040-CV</td><td>500 mL; Phosphate-buffered saline without calcium and magnesium&amp;nbsp;</td></tr><tr><td>RPMI</td><td>Corning&amp;nbsp;</td><td>10-040-CV</td><td>Cell culture media</td></tr><tr><td>Saline</td><td>Hospira</td><td>NDC0409-4888-02</td><td>10 mL single dose; 0.9% sodium chloride injection, USP</td></tr><tr><td>Stopwatch</td><td>iTheraMedical&amp;nbsp;</td><td>4135333</td><td>Used to record minutes and seconds&amp;nbsp;</td></tr><tr><td>Syringes</td><td>Cardinal Health</td><td>1188128012</td><td>1 mL Insulin Syringe; U-100 Insulin only; 27G x 1/2&quot; (0.35 x 12.7 mm)</td></tr><tr><td>Transparent Wound Dressing</td><td>Tegaderm</td><td>1624W</td><td>transparent film dressing frame style; 2 3/8&quot; x 2 3/4&quot; (6 cm x 7 cm)</td></tr><tr><td>Tweezers</td><td>Termo Electron&amp;nbsp;</td><td>7626</td><td>Used to pull skin back when injecting cells into mice</td></tr><tr><td>Ultrasound gel</td><td>EcoVue</td><td>283</td><td>32 g packet, prpylene glycol free, water soluble, paraben and dye free</td></tr><tr><td>Undyed Sutures</td><td>Ethicon</td><td>VR493</td><td>18&quot; cutting; P-3 3/8 13 mm; undyed and braided, synthetic absorbable suture, non-USP</td></tr><tr><td>Warming pad</td><td>Repti Therm UTH</td><td>120VAC 60Hz 8W&amp;nbsp;</td><td>Used to warm animals while under anesthetic;&amp;nbsp;</td></tr><tr><td>Would Splints</td><td>Grace Bio-Labs</td><td>476684</td><td>Clear Silicone, 14 mm OD x 10 mm ID 0.5 thickness with suture sites&amp;nbsp;</td></tr><tr><td>Wound clips</td><td>Reflex 7</td><td>203-1000</td><td>Reflex skin closure system, 7 mm, stainless stee</td></tr></tbody></table>

evaluations of oxygenation and vascular perfusion in pre-clinical models of cancer and wound healing using os-dce oai

Evaluations of Oxygenation and Vascular Perfusion in Pre-Clinical Models of Cancer and Wound Healing Using OS-DCE OAI

Oxygen-sensitive optoacoustic imaging (OS OAI) and dynamic contrast&#8211;enhanced optoacoustic imaging (DCE OAI) provide complementary, noninvasive readouts of tissue physiology. OS OAI leverages multispectral detection of endogenous oxyhemoglobin and deoxyhemoglobin to generate maps of blood oxygen saturation (%sO&#8322;), while DCE OAI tracks the in vivo pharmacokinetics of a near-infrared absorber to quantify vascular perfusion and permeability. The goal of this protocol is to present a unified OS-DCE OAI workflow that enables simultaneous assessment of oxygenation and perfusion in two widely used pre-clinical settings: orthotopic breast cancer tumors and full-thickness cutaneous wounds.
In this protocol, we demonstrated OAI of mouse models of breast cancer or a laceration wound. For OS OAI, multi-slice multispectral scans are acquired at 700&#8211;875 nm to allow spectral unmixing and estimation of %sO&#8322;. For DCE OAI, repeated acquisitions at &#8804;5-s temporal resolution are performed before and after intravenous bolus injection of indocyanine green (ICG), using either multispectral sampling at 700-875 nm or single-wavelength sampling at 800 nm to generate time versus OA signal amplitude curves. The development of animal models, preparation for OA imaging, OS OAI and DCE OAI acquisitions, and analyses to measure characteristics of oxygenation and vascular perfusion are detailed, along with key troubleshooting guidance for motion artifacts, superficial absorbers, and failed injections.
Together, this OS-DCE OAI protocol yields an integrated functional portrait of hypoxia and vascular transport that can detect physiological changes in tumors and wounds earlier than gross anatomical measures. OS-DCE OAI is readily adaptable to other disease models.

OAI signal can generate maps of oxygen saturation in tumors and wounds 
Following acquisition and reconstruction of multispectral OAI datasets, regions of interest (ROIs) can be defined within tumors or wound beds to quantify signal intensity at different wavelengths. Spectral unmixing algorithms are then applied to separate the contributions of oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) from the composite optoacoustic signal. This processing enables the generation of quantitative maps o...

Here, we present a protocol for performing Oxygen Sensitive &#8211; Dynamic Contrast Enhanced Optoacoustic Imaging (OS-DCE OAI) for evaluating pre-clinical models of cancer and wound healing. OS OAI can image oxy&#8209; and deoxyhemoglobin, mapping tissue oxygenation. DCE-OAI can image the pharmacokinetics of an exogenous contrast agent, thereby mapping vascular perfusion.

Oxygen-sensitive optoacoustic imaging (OS OAI) and dynamic contrast&#8211;enhanced optoacoustic imaging (DCE OAI) provide complementary, noninvasive ...

My research focuses on optoacoustic imaging system to measure oxygenation and perfusion of wounds and tumors. Current methods are limited to measuring perfusion and oxygenation simultaneously, but our protocol enable real-time and noninvasive assessment. This protocol is applicable to both preclinical and clinical studies of wounds, tumors, and vascular disease, although it is limited to imaging depth of approximately up to 10 centimeters.To begin, prepare a 2.14-millimolar solution of the indocyanine green, or ICG contrast agent, in sterile water. Filter the solution with a 0.3-micrometer syringe filter and fill a sterile laboratory syringe with 100 microliters of the filtered solution. Now fill the imaging tank with deionized distilled water and set the tank temperature to 36 degrees Celsius for a mouse with less than 25 grams body weight.If performing DCE-OAI, flush a 27-gauge tail vein catheter with heparinized saline. Insert the catheter into a lateral tail vein of an anesthetized mouse and secure it to prevent it from being removed from the tail vein. Confirm that no air bubbles are present.Next, prepare a sterile laboratory syringe with a volume no greater than 500 microliters that can connect to the catheter. Fill the syringe with 100 microliters of 2.14-millimolar ICG. Next, apply a thin layer of clear ultrasound gel to the tumor or wound area.Then apply ultrasound gel to the cradle to make a seal between the cradle and the tumor or wound area. Place the mouse in the cradle according to the manufacturer's instructions. Position the mouse in the holder with the nose firmly inside the nose cone.Use cuffs to restrain the mouse's hands and feet. Use the tooth loop to stabilize the head. When imaging a mouse, use a cradle with a rat nose cone to lift the head from the bottom of the cradle and reduce the risk of accidental drowning if water leaks into the cradle.Now place the mouse and cradle into the OAI instrument according to the manufacturer's instructions. Observe the mouse cradle for any leaks. If performing DCE-OAI, connect the catheter to the syringe containing the contrast agent.Equilibrate the mouse before imaging by allowing 10 minutes for stabilization of mouse physiology in the warm water tank. To position the mouse relative to the OAI transducer, move the mouse or the OAI transducer so that the tumor or wound is located within the multi-slice image set. Optimize the speed of sound for the image set during the equilibration period.Maintain consistent animal orientation and slice position for all mice and at all time points to ensure rigorous results. Select the image slice parameters to acquire multiple slices covering the entire tumor or wound area with a one-millimeter slice thickness. Then select the absorption wavelengths for OS-OAI at 700, 730, 760, 800, 850, and 875 nanometers.Configure signal averaging to acquire 10 averages per wavelength before acquiring the next wavelength and before moving to the next imaging slice. Then set the number of repetitions to maintain a total acquisition time of approximately two minutes. Perform a minimum of three repetitions to ensure measurement stability.Now acquire the OS-OA images using the previously set parameters. Set the DCE-OAI acquisition parameters for a single-slice imaging protocol with multiple wavelengths. Position up to five imaging slices centered on the tumor or wound area with one-millimeter slice thickness.Select the optimal absorption wavelength for the contrast agent by setting the wavelength to 800 nanometers for ICG in an in-vivo environment. Set the number of averages and repetitions to maintain a temporal resolution of five seconds or less and a total acquisition time of 11.0 to 11.2 minutes for a 10-hertz imaging repetition rate. To acquire the DCE-OA images, start the acquisition and collect 12 image sets.Then administer 100 microliters of contrast agent via the catheter while continuing acquisition. Continue imaging to acquire the remaining 128 image sets for 10.2 minutes post-injection to capture wash-in and wash-out kinetics. Monitor the imaging process to ensure images are acquired and observe the mouse breathing rate to confirm stable physiology during scanning.Then remove the mouse and cradle from the instrument. Remove the mouse from the cradle and allow it to recover from anesthesia. Return the mouse to a warmed cage and monitor until ambulatory.Finally, analyze OA images and compute quantitative parameters to assess tumor or wound physiology and contrast dynamics. Quantitative maps of oxyhemoglobin, deoxyhemoglobin, total hemoglobin, and blood oxygen saturation were generated from multi-spectral OAI data sets using spectral unmixing. DCE-OAI provided empirical pharmacokinetic parameters, including maximum signal enhancement, time to peak, slope, area under the curve, signal loss, and contrast enhancement at 10 minutes.Pharmacokinetic modeling enabled estimation of wash-in and wash-out rates, represented by NKtrans and Kep maps. Wound models showed slower wash-out rates immediately after injury that increased during healing, indicating changes in vascular perfusion. This protocol allows a dynamic, non-invasive measurement of tissue oxygenation and perfusion.The key challenge is minimizing motion and maintaining consistent positioning for reliable measurement.

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Research

JoVE Journal

Bioengineering

A dual-mode imaging system was developed for non-contact assessment of cutaneous tissue oxygenation and vascular function.

Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function

We present a diffuse optical spectroscopic (DOS) approach that provides quantitative optical biomarkers of skin response to radiation. We describe DOS instrumentation design, optical parameters extraction algorithms and the animal handling procedures required to yield representative data from a pre-clinical mouse model of radiation induced erythema.

Diffuse Optical Spectroscopy for the Quantitative Assessment of Acute Ionizing Radiation Induced Skin Toxicity Using a Mouse Model

Presented here is a protocol for non-invasively monitoring cerebral hemodynamics of neurocritical patients in real-time and at the bedside using diffuse optics. Specifically, the proposed protocol uses a hybrid diffuse optical systems to detect and display real-time information on cerebral oxygenation, cerebral blood flow and cerebral metabolism.

Real-Time Monitoring of Neurocritical Patients with Diffuse Optical Spectroscopies

The assessment of microvascular function by oxygenation-sensitive cardiac magnetic resonance imaging in combination with vasoactive breathing maneuvers is unique in its ability to assess rapid dynamic changes in myocardial oxygenation in vivo and, thus, may serve as a critically important diagnostic technique for coronary vascular function.

Oxygenation-sensitive Cardiac MRI with Vasoactive Breathing Maneuvers for the Non-invasive Assessment of Coronary Microvascular Dysfunction

This protocol presents a physiologically relevant tumor-on-a-chip model to perform high-throughput basic and translational human cancer research, advancing drug screening, disease modeling, and personalized medicine approaches with a description of loading, maintenance, and evaluation procedures.

Establishing a Physiologic Human Vascularized Micro-Tumor Model for Cancer Research

We describe a protocol to non-invasively and continuously measure absolute microvascular blood flow index and blood oxygen saturation using a multi-modal device based on near-infrared diffuse optics. We then evaluate the metabolic rate of oxygen consumption and reactive hyperemia utilizing a vascular occlusion test.

Non-Invasive Monitoring of Microvascular Oxygenation and Reactive Hyperemia using Hybrid, Near-Infrared Diffuse Optical Spectroscopy for Critical Care

Translation of Intravital microscopy findings is challenged by its shallow depth penetration into tissue. Here we describe a dorsal window chamber mouse model that enables co-registration of intravital microscopy and clinically applicable imaging modalities (e.g., CT, MRI) for direct spatial correlation, potentially streamlining clinical translation of intravital microscopy findings.

A Dorsal Skinfold Window Chamber Tumor Mouse Model for Combined Intravital Microscopy and Magnetic Resonance Imaging in Translational Cancer Research

Here, we describe a non-invasive approach using near-infrared spectroscopy to assess reactive hyperemia in the lower limb. This protocol provides a standardized assessment of vascular and microvascular responsiveness that may be used to determine the presence of vascular dysfunction as well as the efficacy of therapeutic interventions.

Near-Infrared Spectroscopy During Reactive Hyperemia for the Assessment of Lower Limb Vascular Function

Quantitative 3D oxygen maps of murine tumors were imaged noninvasively using Pulse Electron Paramagnetic Resonance. Ultrasound B-mode and Power Doppler were used for anatomy and vascular structure. Images from both modalities were superimposed enabling multi-parametric tumor analysis.

Tumor Hypoxia Assessment: In Vivo 3D Oxygen Imaging Through Electron Paramagnetic Resonance

The objective of this research is to recreate and then access the anatomy of the human cardiac venous system using 3D reconstructions generated from contrast-computed tomography scans.

Anatomical Reconstructions of the Human Cardiac Venous System using Contrast-computed Tomography of Perfusion-fixed Specimens

Learn a unified OS-DCE OAI protocol for simultaneous assessment of oxygenation and vascular perfusion in orthotopic breast cancer tumors and cutaneous wounds using mouse models. This noninvasive method enables early detection of physiological changes.

Evaluations of Oxygenation and Vascular Perfusion in Pre-Clinical Models of Cancer and Wound Healing Using OS-DCE OAI

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