Jimmy R. Roehrig

Clinical Results with R2 Imagechecker System

The ImageChecker M1000 system is a Computer Aided Detection System with image analysis and visual display capabilities intended for use as an aid for a radiologist reading routine screening mammograms. The purpose of the device is to assist the radiologist in minimizing observational lapses by identifying areas on mammograms that may warrant a second review. A large study was conducted to answer three primary questions: Will the presence of spurious markers cause an increase in work-up rate? What is the sensitivity of the device on cancers, particularly on those cancers that the radiologist has failed to take action on? Is the system robust with respect to changes in hardware components such as scanners?

Wave-front tilt power spectral density from the image motion of solar pores

We have constructed an image-stabilization system that measures wave-front tilt over a telescope aperture that is due to atmospheric turbulence. This system uses small features on the Sun as point sources. The wave-front tilt power spectral density has been measured with this system out to more than 500 Hz. The spectra show three distinct asymptotic slopes that do not, in general, agree with theoretical predictions based on the Kolmogorov model.