Developing a professional pathway in health equity to facilitate curricular transformation at the University of Michigan Medical School.

PROBLEM: Medical schools are challenged to realign curricula to address society's needs in a rapidly changing environment, and to support new instruction and assessment methods that require substantial faculty time. APPROACH: In 2010, the University of Michigan Medical school began planning the Global Health and Disparities Path of Excellence (GHD Path), an optional co-curriculum for students interested in health disparities, with explicit goals to (1) draw attention to the school's social mission; (2) test new, faculty-intensive methods of learning and assessment for all students; and (3) serve as a template for additional co-curricular paths. OUTCOMES: Intended outcomes of the program include enhancing students' competency in leadership related to ameliorating health disparities and the study institution's ability to plan feasible and effective schoolwide reforms in self-directed learning, faculty advising systems, narrative-based feedback for goal setting, Web-based student portfolios, and additional Paths of Excellence. NEXT STEPS: During academic year 2013-2014, the GHD Path is adding more community-based experiences. The faculty development and support model will be streamlined to decrease resources required for program development while retaining key features of the advising system. Lessons from the GHD Path are central to planning schoolwide reform of instructional methods, faculty advising, and student portfolios. The use of a small-scale program to pilot new ideas to inform longer-term, larger-scale changes at our institution might prove useful to other schools striving to meet societal needs while implementing innovative methods of instruction and assessment.

Evaluation of preprocessing steps to compensate for magnetic field distortions due to body movements in BOLD fMRI.

Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is currently the dominant technique for non-invasive investigation of brain functions. One of the challenges with BOLD fMRI, particularly at high fields, is compensation for the effects of spatiotemporally varying magnetic field inhomogeneities (DeltaB(0)) caused by normal subject respiration and, in some studies, movement of the subject during the scan to perform tasks related to the functional paradigm. The presence of DeltaB(0) during data acquisition distorts reconstructed images and introduces extraneous fluctuations in the fMRI time series that decrease the BOLD contrast-to-noise ratio. Optimization of the fMRI data-processing pipeline to compensate for geometric distortions is of paramount importance to ensure high quality of fMRI data. To investigate DeltaB(0) caused by subject movement, echo-planar imaging scans were collected with and without concurrent motion of a phantom arm. The phantom arm was constructed and moved by the experimenter to emulate forearm motions while subjects remained still and observed a visual stimulation paradigm. These data were then subjected to eight different combinations of preprocessing steps. The best preprocessing pipeline included navigator correction, a complex phase regressor and spatial smoothing. The synergy between navigator correction and phase regression reduced geometric distortions better than either step in isolation and preconditioned the data to make them more amenable to the benefits of spatial smoothing. The combination of these steps provided a 10% increase in t-statistics compared to only navigator correction and spatial smoothing and reduced the noise and false activations in regions where no legitimate effects would occur.

Hybrid two-dimensional navigator correction: a new technique to suppress respiratory-induced physiological noise in multi-shot echo-planar functional MRI.

A troublesome source of physiological noise in functional magnetic resonance imaging (fMRI) is due to the spatio-temporal modulation of the magnetic field in the brain caused by normal subject respiration. fMRI data acquired using echo-planar imaging are very sensitive to these respiratory-induced frequency offsets, which cause significant geometric distortions in images. Because these effects increase with main magnetic field, they can nullify the gains in statistical power expected by the use of higher magnetic fields. As a study of existing navigator correction techniques for echo-planar fMRI has shown that further improvements can be made in the suppression of respiratory-induced physiological noise, a new hybrid two-dimensional (2D) navigator is proposed. Using a priori knowledge of the slow spatial variations of these induced frequency offsets, 2D field maps are constructed for each shot using spatial frequencies between +/-0.5 cm(-1) in k-space. For multi-shot fMRI experiments, we estimate that the improvement of hybrid 2D navigator correction over the best performance of one-dimensional navigator echo correction translates into a 15% increase in the volume of activation, 6% and 10% increases in the maximum and average t-statistics, respectively, for regions with high t-statistics, and 71% and 56% increases in the maximum and average t-statistics, respectively, in regions with low t-statistics due to contamination by residual physiological noise.