Medical Imaging Technology Innovations to Minimize the Safety Risks of Angiography for Chronic Kidney Disease Patients
Cardiovascular Disease (CVD) is the leading cause of death in the United States. CVD is
caused by a buildup of plaque in the blood vessels of the heart and brain. CVD is comorbid
with Peripheral Vascular Disease (PVD), which is a buildup of plaque in the extremities
and organs below the stomach. Medical imaging is a clinically indispensable tool for diagnosing CVD and PVD, as well as guiding real-time interventional procedures. Currently,
the two main procedures for diagnosing CVD and PVD are X-Ray and CT angiography,
both of which rely on injection of iodinated contrast agents. However, about 25% of patient
undergoing these procedures suer from Chronic Kidney Disease (CKD). For this patient
subpopulation, iodinated contrast agents are risky and can lead to complete kidney failure.
Physicians risk damaging patients' kidneys in order to alleviate the more imminent threat of
death from a heart attack. Hence, an open challenge remains to develop a safer diagnostic
angiography method that could match current methods in resolution, contrast, and speed.
Here we introduce and develop two new imaging methods for imaging patients with CKD.
The rst method is MR Saline Angiography, an alternative Magnetic Resonance (MR) based
angiographic method for coronary imaging. In combination with the inherent resolution and
speed of traditional MR methods, MR Saline Angiography has the advantage of utilizing
saline as a safe contrast agent. This approach is an improvement upon the commonly used
Gadolinium-based contrast agent that is also toxic to patients with CKD. Using a novel
electromagnetically shielded catheter and a tailored pulse sequence, we have demonstrated
that MR Saline Angiography is a feasible alternative for imaging coronary arteries. The second method is Magnetic Particle Imaging (MPI), a tracer imaging modality, which images
Superparamagnetic Iron Oxide nanoparticles. MPI is an emerging imaging technique with
possible applications in angiography as well as targeted and non-targeted tumor imaging,
hyperthermia, perufsion, cell tracking and targeted drug delivery. Here we study the feasibility
of MPI as an angiographic imaging method by looking at short-term biodistribution
and long-term iron clearance for two most common MPI tracers.