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Full-Text Articles in Medicine and Health Sciences
Contrast Enhanced-Magnetic Resonance Imaging As A Surrogate To Map Verteporfin Delivery In Photodynamic Therapy, Kimberley S. Samkoe, Amber Bryant, Jason R. Gunn, Stephen P. Pereira, Tayyaba Hasan, Brian W. Pogue
Contrast Enhanced-Magnetic Resonance Imaging As A Surrogate To Map Verteporfin Delivery In Photodynamic Therapy, Kimberley S. Samkoe, Amber Bryant, Jason R. Gunn, Stephen P. Pereira, Tayyaba Hasan, Brian W. Pogue
Dartmouth Scholarship
The use of in vivo contrast-enhanced magnetic resonance (MR) imaging as a surrogate for photosensitizer (verteporfin) dosimetry in photodynamic therapy of pancreas cancer is demonstrated by correlating MR contrast uptake to ex vivo fluorescence images on excised tissue. An orthotopic pancreatic xenograft mouse model was used for the study. A strong correlation ([i]r=0.57 ) was found for bulk intensity measurements of T1-weighted gadolinium enhancement and verteporfin fluorescence in the tumor region of interest. The use of contrast-enhanced MR imaging shows promise as a method for treatment planning and photosensitizer dosimetry in human photodynamic therapy (PDT) of pancreas …
Impact Of Treatment Response Metrics On Photodynamic Therapy Planning And Outcomes In A Three-Dimensional Model Of Ovarian Cancer, Sriram Anbil, Imran Rizvi, Jonathan P. Celli, Nermina Alagic, Brian W. Pogue, Tayyaba Hasan
Impact Of Treatment Response Metrics On Photodynamic Therapy Planning And Outcomes In A Three-Dimensional Model Of Ovarian Cancer, Sriram Anbil, Imran Rizvi, Jonathan P. Celli, Nermina Alagic, Brian W. Pogue, Tayyaba Hasan
Dartmouth Scholarship
Common methods to characterize treatment efficacy based on morphological imaging may misrepresent outcomes and exclude effective therapies. Using a three-dimensional model of ovarian cancer, two functional treatment response metrics are used to evaluate photodynamic therapy (PDT) efficacy: total volume, calculated from viable and nonviable cells, and live volume, calculated from viable cells. The utility of these volume-based metrics is corroborated using independent reporters of photodynamic activity: viability, a common fluorescence-based ratiometric analysis, and photosensitizer photobleaching, which is characterized by a loss of fluorescence due in part to the production of reactive species during PDT. Live volume correlated with both photobleaching …
White Light-Informed Optical Properties Improve Ultrasound-Guided Fluorescence Tomography Of Photoactive Protoporphyrin Ix, Brendan P. Flynn, Alisha V. Dsouza, Stephen C. Kanick, Scott C. Davis, Brian W. Pogue
White Light-Informed Optical Properties Improve Ultrasound-Guided Fluorescence Tomography Of Photoactive Protoporphyrin Ix, Brendan P. Flynn, Alisha V. Dsouza, Stephen C. Kanick, Scott C. Davis, Brian W. Pogue
Dartmouth Scholarship
Subsurface fluorescence imaging is desirable for medical applications, including protoporphyrin-IX (PpIX)-based skin tumor diagnosis, surgical guidance, and dosimetry in photodynamic therapy. While tissue optical properties and heterogeneities make true subsurface fluorescence mapping an ill-posed problem, ultrasound-guided fluorescence-tomography (USFT) provides regional fluorescence mapping. Here USFT is implemented with spectroscopic decoupling of fluorescence signals (auto-fluorescence, PpIX, photoproducts), and white light spectroscopy-determined bulk optical properties. Segmented US images provide a priori spatial information for fluorescence reconstruction using region-based, diffuse FT. The method was tested in simulations, tissue homogeneous and inclusion phantoms, and an injected-inclusion animal model. Reconstructed fluorescence yield was linear with PpIX …