2015 Galvanizing Engineering in Medicine (GEM) Awards

The CTRI announces the selection of four physician-engineer teams as the 2015 recipients of the GEM awards. GEM, an initiative of the CTRI and the UC San Diego Institute of Engineering in Medicine (IEM), supports projects that identify clinical challenges for which engineering solutions can be developed and implemented to improve health care. The GEM recipients and their projects are below.

Gert Cauwenberghs, PhD Jacobs School of Engineering Gabriel Silva, PhD Jacobs School of EngineeringWilliam Freeman, MD Department of Ophthalmology UC San Diego
Gert Cauwenberghs, PhD
Jacobs School of Engineering
Gabriel Silva, PhD
Jacobs School of Engineering
William Freeman, MD
Department of Ophthalmology
UC San Diego

Title: Micropower Integrated Nano-engineered Retinal Interface

Common retinal degenerative disorders such as retinitis pigmentosa and age-related macular degeneration cause irreversible loss of vision. Retinal prosthetic devices replace the retinal photoreceptor functions by producing electrical stimulation for inducing visual perception artificially. However, recent retinal prostheses have achieved very limited success in regaining vision–achieving only up to a few dozen of pixelized phosphenes. This project pursues a fully integrated nano-engineered retinal prosthesis that completely departs from the status quo with a path forward to restore natural, high-resolution vision in the affected population. The engineering effort pertains to the design and development of high-performance light-sensitive electrode arrays, as well as innovation in the wireless interface, communication, stimulation waveform generation, system control, and biocompatible packaging and surgical assembly. The project will culminate with in vivo experiments for validation of restored light responsivity through the nano-engineered implant in a rabbit model, as a stepping stone to further developments toward clinical trials.

Juan Carlos del Alamo, PhD Jacobs School of Engineering Andrew Kahn, MD, PhD Division of Cardiovascular Medicine UC San Diego
Juan Carlos del Alamo, PhD
Jacobs School of Engineering
Andrew Kahn, MD, PhD
Division of Cardiovascular Medicine
UC San Diego

Title: Solution: Development of Patient-specific Indices of Left-ventricular Blood Stasis by Echocardiographic Imaging and Analyses of Intraventricular Flow

Congestive heart failure affects over five million people in the United States. Approximately half of these people have left ventricular systolic dysfunction, a disorder in which the main pumping chamber of the heart is weaker than normal. These patients have an increased risk of thrombi  forming within the heart, which can then embolize to the brain, causing strokes. Consequently, the rate of stroke in these patients is much higher than normal. Blood thinning medications are known to decrease the risk of thrombi forming and causing strokes, but are generally not used because this benefit is offset by an increased risk of internal bleeding.

Blood stasis is known to increase the risk of thrombus formation by initiating the coagulation cascade. We hypothesize that assessment of left ventricular blood flow patterns and stasis by novel analyses of echocardiographic data can predict the risk of intraventricular thrombus formation. To test this hypothesis, we will develop and implement several patient-specific indices of left-ventricular blood stasis based on imaging data and computational analyses of left ventricular flow, transport, and mixing. We will then test these indices in patients with left ventricular systolic dysfunction and a history of blood clots in the heart, and compare the results with those from a matched group without a history of blood clots. Our overall goal is to improve patient outcomes and decrease stroke rates by identifying those patients who would most benefit from treatment with blood thinning medication.

Andrew D. McCulloch, PhD Jacobs School of Engineering David Krummen, MD Division of Cardiovascular Medicine UC San Diego
Andrew D. McCulloch, PhD
Jacobs School of Engineering
David Krummen, MD
Division of Cardiovascular Medicine
UC San Diego

Title: Development of a Non-Invasive Quantitative Tool to Detect and Localize Human Ventricular Fibrillation Mechanisms

Ventricular fibrillation (VF) is a life threatening arrhythmia for which therapy targeting its sustaining mechanisms is not routinely available. Recent data from our laboratory suggest that electrical rotors are important drivers of sustained VF. Electrical rotors are areas of spinning electrical activation located at sites throughout the heart which perpetuate fibrillation. Using biventricular, 64-electrode basket catheter endocardial mapping in humans, we have shown that VF rotor ablation decreases VF inducibility and clinical events in an animal model and a patient with VF. It would be clinically useful to detect and localize VF rotors using noninvasive methods in order to identify candidates for targeted treatment and help guide the ablation of rotors, prior to invasive mapping.

In this project, we aim to develop a non-invasive tool to quantitatively analyze the Electrocardiogram (ECG) during VF to determine the specific types of VF-sustaining mechanisms present (rotor or focal source). It will also determine the location of such sources to help guide targeted therapy of VF. If successful, this project may allow more widespread use of radiofrequency ablation to reduce the burden of VF in patients at high risk of the arrhythmia.

Donald J. Sirbuly, PhD NanoEngineering Department Robert Weinreb, MD Shiley Eye Institute UC San Diego
Donald J. Sirbuly, PhD
NanoEngineering Department
Robert Weinreb, MD
Shiley Eye Institute
UC San Diego

Title: Continuous and Direct Intraocular Pressure Monitoring via Fluid-sensitive 3D Photonic Crystal Implants

Glaucoma is a neurodegenerative disease that affects over 60 million people around the world and more than three million in the U.S. This disease, if not properly monitored and treated, is the leading cause of irreversible blindness. Although glaucoma is a complex eye disease, pressure inside the eye (i.e. intraocular pressure or IOP) is recognized as the leading risk factor for disease and pressure also may be a causal factor in some glaucoma patients. Normal eye pressures typically range from 12-22 mm Hg, but can fluctuate very rapidly from day to day or even within hours. This makes single measurements at periodic eye exams a weak indicator of the status of the disease. Ideally, patients would have their IOP monitored throughout the 24-hour day to get meaningful statistics. However, this currently can only be achieved by visiting the doctor and using instruments such as a tonometer. There is therefore an immediate need for the development of a continuous IOP sensor that can accurately collect pressure data more frequently, particularly while the patient is away from the doctor's office. In this proposal we aim to develop an IOP sensor implant that transmits pressure data through a color change of a 3D photonic crystal (3DPC). We will use self-assembly and 3D printing techniques to fabricate small (< 5 mm3) 3DPC implants with a pressure sensitivity of < 1 mm Hg. The colorimetric change will be correlated to the IOP and can be read-out at any time interval using a standard iPhone camera.