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Carta Revisado por pares

F. Graham Sommer,

... 147–156. Crossref, Medline, Google Scholar3 Krishnamurthi G, Stantz KM, Steinmetz R, et al. Functional imaging in small animals using x-ray computed tomography: study of physiologic measurement reproducibility. IEEE ...

Tópico(s): Pediatric Urology and Nephrology Studies

2007 - Radiological Society of North America | Radiology

Artigo

Ganapathy Krishnamurthi, Keith M. Stantz, Ralf Steinmetz, Vincent H. Gattone, Minsong Cao, Gary D. Hutchins, Yun Liang,

X-ray computed tomography (CT) has been traditionally used for morphologic analysis and in the recent past has been used for physiology imaging. This paper seeks to demonstrate functional CT as an effective tool for monitoring changes in tissue physiology associated with disease processes and cellular and molecular level therapeutic processes. We investigated the effect of noise and sampling time on the uncertainty of tissue physiologic parameters. A whole body compartmental model of mouse was formulated ...

Tópico(s): Medical Imaging Techniques and Applications

2005 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Medical Imaging

Artigo

Robert A. Kruger, Daniel R. Reinecke, Gabe A. Kruger, Michael Thornton, Paul A. Picot, Timothy G. Morgan, Keith M. Stantz, Charles A. Mistretta,

We have designed and built a prototype PCT (photoacoustic CT) scanner suitable for small animal imaging that acquires a sparse set of 128 photoacoustic, radial "projections" uniformly distributed over the surface of a hemisphere in response to optical absorption from a tunable, pulsed NIR (near-infrared) laser. Acquisition of a denser set of projections is achieved by rotating the hemispherical array about its vertical axis and acquiring additional, interleaved projections. Each detector in the array ...

Tópico(s): Optical Imaging and Spectroscopy Techniques

2009 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Artigo Acesso aberto Revisado por pares

Ning Cao, Minsong Cao, Helen Chin-Sinex, Marc S. Mendonca, Song-Chu Ko, Keith M. Stantz,

To image the intratumor vascular physiological status of pancreatic tumors xenografts and their response to anti-angiogenic therapy using dynamic contrast-enhanced computed tomography (DCE-CT), and to identify parameters of vascular physiology associated with tumor x-ray sensitivity after anti-angiogenic therapy.Nude mice bearing human BxPC-3 pancreatic tumor xenografts were treated with 5 Gy of radiation therapy (RT), either a low dose (40 mg/kg) or a high dose (150 mg/kg) of DC101, the anti-VEGF receptor- ...

Tópico(s): Cancer, Hypoxia, and Metabolism

2014 - Elsevier BV | International Journal of Radiation Oncology*Biology*Physics

Artigo

Keith M. Stantz, Yun Liang, Cristopher A. Meyer, Shawn D. Teague, Mark M. Stecker, Gary D. Hutchins, Gordon McLennan, Scott A. Persohn,

Purpose: To evaluate whether functional multi-slice computed tomography (MSCT) can identify regional areas of normally perfused and ischemic myocardium in a porcine model. Material and Methods: Three out bred pigs, two of which had ameroids surgically implanted to constrict flow within the LAD and LCx coronary arteries, were injected with 25 mL of iopromide (Isovue) at a rate of 5 mL/second via the femoral or jugular vein. Sixty axial scans along the short axis of the heart was acquired on a 16-slice CT scanner ( ...

Tópico(s): Advanced X-

2003 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Artigo Acesso aberto Revisado por pares

Yiu-Hsin Chang, Devin Miles, P. Harter, Jogendra Singh Pawar, Chang‐Deng Hu, Keith M. Stantz,

... its down-regulator TREX1 when exposed to X-ray (low-LET) and fast neutron (high-LET). Our ...

Tópico(s): Viral Infections and Vectors

2022 - Elsevier BV | Biophysical Journal

Artigo Acesso aberto

Justin Sick, Nicholas J. Rancilio, Caroline V. Fulkerson, Jeannie M. Plantenga, Deborah W. Knapp, Keith M. Stantz,

Background and purposeUltrasound (US) is a non-invasive, non-radiographic imaging technique with high spatial and temporal resolution that can be used for localizing soft-tissue structures and tumors in real-time during radiotherapy (RT) (inter- and intra-fraction). A comprehensive approach incorporating an in-house 3D-US system within RT is presented. This system is easier to adopt into existing treatment protocols than current US based systems, with the aim of providing millimeter intra-fraction ...

Tópico(s): Advanced X-

2019 - Elsevier BV | Physics and Imaging in Radiation Oncology

Artigo

Yun Liang, Keith M. Stantz, Ganapathy Krishnamurthi, Rosemary Steinmetz, Gary D. Hutchins,

Micro-computed tomography (microCT) is capable of obtaining high-resolution images of skeletal tissues. However its image contrast among soft tissues remains inadequate for tumor detection. High speed functional computed tomography will be needed to image tumors by employing x-ray contrast medium. The functional microCT development will not only facilitate the image contrast enhancement among different tissues but also provide information of tumor physiology. To demonstrate the feasibility of functional ...

Tópico(s): Medical Imaging Techniques and Applications

2003 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Artigo Revisado por pares

Ning Cao, Seung Hyun Song, Minsong Cao, Michael Shaffer, T. Maleki, Babak Ziaie, Sungahn Ko, Keith M. Stantz,

Purpose: The objectives are to: 1) longitudinally monitor and evaluate the physiology and oxygenation status of pancreatic tumor after treatment by anti‐angiogenic drug (DC101, anti‐VEGFR2 monoclonal antibody); and 2) to generate oxygen within tumor using a novel device, Implantable Micro‐ Oxygen Generator, IMOG. Functional and molecular imaging modalities, Dynamic Contrast‐Enhanced CT (DCE‐CT) and Photoacoustic Computed Tomography Spectroscopy (PCT‐S) will be used to longitudinally monitor tumor responses ...

Tópico(s): Cancer Research and Treatments

2012 - Wiley | Medical Physics

Artigo Revisado por pares

Ning Cao, Seung Hyun Song, Michael Shaffer, T. Maleki, María González Cao, Chia‐Sui Kao, Keith M. Stantz, Babak Ziaie, Sungahn Ko,

Purpose/Objective(s)Over the past decades, little progress has been made to improve the extremely low survival rates observed in patients diagnosed with pancreatic cancer (overall 5-year survival rate is less than 5%). Extreme hypoxia observed in pancreatic tumors significantly contributes to the ineffectiveness of conventional radiation and chemotherapy. To overcome this hypoxia-induced ineffective radiation treatment, we used a novel device, the Implantable Micro-oxygen Generator (IMOG) for in-situ ...

Tópico(s): Molecular Communication and Nanonetworks

2012 - Elsevier BV | International Journal of Radiation Oncology*Biology*Physics

Artigo

Keith M. Stantz, Bo Liu, Robert A. Kruger,

Purpose: The purpose of this study is to evaluate the influence of photon propagation on the NIR spectral features associated with photoacoustic imaging. Introduction: Photoacoustic CT spectroscopy (PCT-S) has the potential to identify molecular properties of tumors while overcoming the limited depth resolution associated with optical imaging modalities (e.g., OCT and DOT). Photoacoustics is based on the fact that biological tissue generates high-frequency acoustic signals due to volume of expansion ...

Tópico(s): Optical Imaging and Spectroscopy Techniques

2007 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Artigo

Minsong Cao, Keith M. Stantz, Yun Liang,

Initial animal study for quantifying myocardial physiology through contrast-enhanced dynamic x-ray CT suggested that beam hardening is one of the limiting factors for accurate regional physiology measurement. In this study, a series of simulations were performed to investigate its deterioration effects and two correction algorithms were adapted to evaluate for their efficiency in improving the measurements. The simulation tool consists of a module simulating data acquisition of a real polyenergetic ...

Tópico(s): Medical Imaging Techniques and Applications

2006 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Artigo

Ganapathy Krishnamurthi, Keith M. Stantz, Rosemary Steinmetz, Gary D. Hutchins, Yun Liang,

High-speed X-ray computed tomography (CT) has the potential to observe the transport of iodinated radio-opaque contrast agent (CA) through tissue enabling the quantification of tissue physiology in organs and tumors. The concentration of Iodine in the tissue and in the left ventricle is extracted as a function of time and is fit to a compartmental model for physiologic parameter estimation. The reproducibility of the physiologic parameters depend on the (1) The image-sampling rate. According to our ...

Tópico(s): Advanced MRI Techniques and Applications

2004 - SPIE | Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE