The invention provides methods and apparatus for enhanced PCI and dual-use radiation imaging systems. In one implementation high resolution storage phosphor plate radiation detector (an area detector) is employed for conventional attenuation radiation imaging and/or PCI (including conventional PCI and coded aperture PCI). Slit and slot scan implementations for dual-use systems are introduced. Dedicated single and dual-use slit and slot scan system for conventional attenuation imaging and PCI are described that employ face-on or edge-on detectors. Slit and slot scan systems that employ area detectors are described. Edge-on, structured cell detector designs are described. Applications of edge-on structured cell detectors for CT, Nuclear Medicine, PET, and probe detectors are described.