Andrew Girard

Mentor: Dr. Thomas Mareci
College of Medicine
"I began research at the McKnight Brain Institute because I wanted to learn skills and concepts beyond the scope of the classroom that will be useful to me as a student and future physician. Afters years of study and experimentation in the lab, I applied for the University Scholars program because I wanted to gain more independence in the research process by undertaking a yearlong project and submitting my work for publication. Ultimately, I hope to contribute towards diagnostic advancements which have a significant impact for patients battling diseases and chronic conditions."

Major

Chemical Engineering

Minor

Health Disparities in Society

Research Interests

  • Magnetic Resonance Imaging
  • Electromagnetism
  • Medicine

Academic Awards

  • UF Anderson Scholar Award 2014
  • UF HHMI Science for Life Research Award 2014
  • Dean's List
  • University Scholars Program 2016

Organizations

  • Kappa Sigma Fraternity
  • Tau Beta Pi Engineering Honor Society
  • Community Health Service Corps

Volunteer

  • Shands Hospital
  • Disability Resource Center
  • UF Mobile Outreach Clinic

Hobbies and Interests

  • Hiking
  • Traveling
  • Fishing
  • Football

Research Description

The Mapping of Current Density in an Excised Rat Brain Using Magnetic Resonance Electrical Impedance Tomography
The goal of my research is to map current density in vivo using a technique known as Magnetic Resonance Electrical Impedance Tomography (MREIT). Mapping the current density distribution due to electrical stimulation therapies like Deep Brain Stimulation and Transcranial Direct Current Stimulation can provide vital insights into the underlying regions affected by the treatment, thereby improving the treatment’s efficacy. MREIT is sensitive to phase changes produced in the static magnetic field due to injected currents. These phase changes can be used to compute the magnetic field produced by the current, and the current density distribution can be estimated by solving the inverse problem using Maxwell’s equations. Magnetic fields produced due to low amplitude currents, as used in therapy, are extremely small (on the order of nano tesla) and could be easily masked by the inherent drift of the MRI scanner. Therefore, in order to successfully measure these currents, ensuring that the drift of the static magnetic field is negligible for time periods of data acquisition is warranted. A 4.7 T magnet system will be used for the data acquisition and the stability of the static field will be assessed. After confirming the stability of the main magnetic field, current will be injected using electrodes implanted into an excised rat brain while acquiring images at 4.7 T. The magnetic field maps obtained will be used to compute the current density maps in tissue.