Microscintigraphy with high resolution collimators and radiographic detectors.

The potential use of high resolution collimators with standard radiographic detectors in place of conventional gamma cameras for high resolution microscintigraphy is presented. Polycapillary multiple hole collimators are shown to provide 10-100 micron scale spatial resolution. A series of images from arrays of 125I brachytherapy seeds in Lucite phantoms display resolution better than 0.1 mm with good sensitivity and a 30 mm field of view. In addition to application to brachytherapy seed localization, such "cellular" level resolution is necessary for high-resolution in vivo imaging in mouse models. The system could also enable the use of a wider variety of isotopes, including much lower photon energy isotopes in nuclear medicine, as the high resolution collimator allows more flexibility in detector constraints.