1. Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, 200 1st St. SW, Rochester, MN 55905, USA
2. Department of Quantitative Health Sciences, Mayo Clinic College of Medicine and Science, 200 1st St. SW, Rochester, MN 55905, USA
3. Department of Ophthalmology, Mayo Clinic College of Medicine and Science, 200 1st St. SW, Rochester, MN 55905, USA
4. Department of Radiology, Mayo Clinic College of Medicine and Science, 200 1st St. SW, Rochester, MN 55905, USA