  We present an approach for utilizing astrometric orbit information to improve
the yield of planetary images and spectra from a follow-on direct detection
mission. This approach is based on the notion-strictly hypothetical-that if a
particular star could be observed continuously, the instrument would in time
observe all portions of the habitable zone so that no planet residing therein
could be missed. This strategy could not be implemented in any realistic
mission scenario. But if an exoplanet's orbit is known from astrometric
observation, then it may be possible to plan and schedule a sequence of imaging
observations that is the equivalent of continuous observation. A series of
images-optimally spaced in time-could be recorded to examine contiguous
segments of the orbit. In time, all segments would be examined, leading to the
inevitable detection of the planet. In this paper, we show how astrometric
orbit information can be used to construct such a sequence. Using stars from
astrometric and imaging target lists, we find that the number of observations
in this sequence typically ranges from 2 to 7, representing the maximum number
of observations required to find the planet. The probable number of
observations ranges from 1.5 to 3.1. This is a dramatic improvement in
efficiency over previous methods proposed for utilizing astrometric orbits. We
examine how the implementation of this approach is complicated and limited by
operational constraints. We find that it can be fully implemented for internal
coronagraph and visual nuller missions, with a success rate approaching 100%.
External occulter missions will also benefit, but to a lesser degree.
