Surgical Procedures, Operative Commons^™

Improved Sensitivity To Fluorescence For Cancer Detection In Wide-Field Image-Guided Neurosurgery, Michael Jermyn, Yoann Gosselin, Pablo A. Valdes, Mira Sibai, Kolbein Kolste

Dartmouth Scholarship

In glioma surgery, Protoporphyrin IX (PpIX) fluorescence may identify residual tumor that could be resected while minimizing damage to normal brain. We demonstrate that improved sensitivity for wide-field spectroscopic fluorescence imaging is achieved with minimal disruption to the neurosurgical workflow using an electron-multiplying charge-coupled device (EMCCD) relative to a state-of-the-art CMOS system. In phantom experiments the EMCCD system can detect at least two orders-of-magnitude lower PpIX. Ex vivo tissue imaging on a rat glioma model demonstrates improved fluorescence contrast compared with neurosurgical fluorescence microscope technology, and the fluorescence detection is confirmed with measurements from a clinically-validated spectroscopic probe. Greater PpIX …

Feasibility Of Atrial Delivery And Tracking Of Stem Cells In A Porcine Model, Nina Garlie, Timothy Hacker, Eric G. Schmuck, Jill Koch, Jayant Khitha, Amish Raval, Indrajit Choudhuri

Journal of Patient-Centered Research and Reviews

Background: Many patients undergoing open heart surgery have sinus node dysfunction and atrial fibrillation, leading to adverse outcomes. Mesenchymal stem cells (MSC) delivered at the time of surgery may have a reparative effect on atrial tissue, thereby improving sinus node function and reducing or preventing atrial fibrillation. Stem cell delivery to the atrium is entirely unstudied. This is a significant gap in medical research, as atrial disease contributes significantly to health care costs.

Purpose: The purpose of this pilot study is to establish a technique to deliver MSC to the atria through an open-chest model, to assess the safety of …

Initial Validation Of A Novel Method Of Presurgical Language Localization Through Functional Connectivity (Fcmri), Stephanie M. Noble, Dustin Scheinost, Susan Y. Bookheimer, Patricia Walshaw, R Todd Constable, Christopher F. Benjamin

Yale Day of Data

OBJECTIVE: Neurosurgery is potentially curative in chronic epilepsy but can only be offered to patients if the surgical risk to language is known. Clinical functional magnetic resonance imaging (fMRI) is an ideal, noninvasive method for localizing language cortex yet remains to be validated for this purpose. We have recently presented a novel method for localizing language cortex. Here we present a preliminary evaluation of this method’s validity. We hypothesized language regions identified using this novel method would demonstrate stronger functional connectivity than randomly generated set of proximal networks. METHOD: fMRI data were collected from sixteen temporal lobe patients …

Review Of Fluorescence Guided Surgery Visualization And Overlay Techniques, Jonathan T. Elliott, Alisha V. Dsouza, Scott C. Davis, Jonathan D. Olson, Keith Paulsen, David Roberts, Brian Pogue

Dartmouth Scholarship

In fluorescence guided surgery, data visualization represents a critical step between signal capture and display needed for clinical decisions informed by that signal. The diversity of methods for displaying surgical images are reviewed, and a particular focus is placed on electronically detected and visualized signals, as required for near-infrared or low concentration tracers. Factors driving the choices such as human perception, the need for rapid decision making in a surgical environment, and biases induced by display choices are outlined. Five practical suggestions are outlined for optimal display orientation, color map, transparency/alpha function, dynamic range compression, and color perception check.

Speckle-Tracking Echocardiographic Measures Of Right Ventricular Function Correlate With Improvement In Exercise Function After Percutaneous Pulmonary Valve Implantation., Shahryar M. Chowdhury, Ziyad M. Hijazi, John T. Fahey, John F. Rhodes, Saibal Kar, Raj Makkar, Michael Mullen, Qi-Ling Cao, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Speckle-tracking echocardiographic (STE) measures of right ventricular (RV) function appear to improve after transcatheter pulmonary valve implantation (TPVI). Measures of exercise function, such as ventilatory efficiency (the minute ventilation [VE]/carbon dioxide production [VCO2] slope), have been shown to be prognostic of mortality in patients who may require TPVI. The aim of this study was to evaluate the correlation between STE measures of RV function and changes in VE/VCO2 after TPVI.

METHODS: Speckle-tracking echocardiography and cardiopulmonary exercise testing were performed at baseline and 6 months after TPVI in 24 patients from four centers. Conventional echocardiographic measures of RV function were …

Clinical Outcomes After Drug-Eluting Stents Versus Coronary Artery Bypass Surgery In High Surgical Risk Patients With Left Main Or Three-Vessel Coronary Artery Disease, Tonga Nfor, Kambiz Shetabi, Wael Hassan, Quinta Nfor, Jayant Khitha, Anjan Gupta, Tanvir Bajwa, Suhail Allaqaband

Journal of Patient-Centered Research and Reviews

Purpose

Previous studies comparing percutaneous coronary intervention (PCI) with coronary artery bypass graft surgery (CABG) in patients with unprotected left main or three-vessel coronary artery disease (LM-3VD) have excluded patients at high surgical risk. We compared clinical outcomes after PCI with drug-eluting stents to CABG in high surgical risk patients with LM-3VD.

Methods

Patients with symptomatic LM-3VD who had Society of Thoracic Surgeons (STS)-predicted operative mortality >5% and were undergoing either PCI with drug-eluting stents or CABG at a tertiary care center from January 2009 to December 2010 were enrolled in this nonrandomized prospective study.

Results

Mean STS score was …

Characteristics Of A Novel Treatment System For Linear Accelerator–Based Stereotactic Radiosurgery, Ning Wen, Haisen Li, Kwang Song, Karen Chin-Snyder, Yujiao Qin, Jinkoo Kim, Maria Bellon, Misbah Gulam, Stephen Gardner, Anthony Doemer, Suneetha Devpura, James Gordon, Indrin Cherry, Farzan Siddiqui, Munther Ajlouni, Robert Pompa, Zane Hammoud, Michael Simoff, Steven Kalkanis, Benjamin Movsas, M. Salim Siddiqui

Internal Medicine Faculty Publications

The purpose of this study is to characterize the dosimetric properties and accuracy of a novel treatment platform (Edge radiosurgery system) for localizing and treating patients with frameless, image-guided stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT). Initial measurements of various components of the system, such as a comprehensive assessment of the dosimetric properties of the flattening filter-free (FFF) beams for both high definition (HD120) MLC and conical cone-based treatment, positioning accuracy and beam attenuation of a six degree of freedom (6DoF) couch, treatment head leakage test, and integrated end-to-end accuracy tests, have been performed. The end-to-end test of the …

Quantitative Spatial Frequency Fluorescence Imaging In The Sub-Diffusive Domain For Image-Guided Glioma Resection, Mira Sibai, Israel Veilleux, Jonathan T. Elliott, Frederic Leblond, Brian Wilson

Dartmouth Scholarship

Intraoperative 5- aminolevulinic acid induced-Protoporphyrin IX (PpIX) fluorescence guidance enables maximum safe resection of glioblastomas by providing surgeons with real-time tumor optical contrast. However, visual assessment of PpIX fluorescence is subjective and limited by the distorting effects of light attenuation and tissue autofluorescence. We have previously shown that non-invasive point measurements of absolute PpIX concentration identifies residual tumor that is otherwise non-detectable. Here, we extend this approach to wide-field quantitative fluorescence imaging by implementing spatial frequency domain imaging to recover tissue optical properties across the field-of-view in phantoms and ex vivo tissue.

Accurate Modelling And Positioning Of A Magnetically-Controlled Catheter Tip, Vi T. H. Le

Theses: Doctorates and Masters

This thesis represents the initial phase of a proposed operator and patient friendly method designed to semi-automate the positioning and directing of an intravascular catheter in the human heart using a variable electromagnetically induced field to control a catheter tip equipped with three tiny fixed magnets oriented in XYZ planes. Here we demonstrate a comprehensive mathematical model which accurately calculates the magnetic field generated by the electromagnet system, and the magnetic torques and forces exerted on a three-magnet tip catheter. From this we have developed an iterative predictive computer algorithm to show the displacement and deflection of the catheter tip. …