1. A molecular breast imaging system comprising: a first planar gamma detector positioned opposite a second planar gamma detector, each configured to receive photons emitted from a radionuclide present in a subject's breast that is positioned between the first and second gamma detectors; and a processor configured to produce a first detector image associated with photons received by the first gamma detector and a second detector image associated with photons received by the second gamma detector and apply a filter configured to selectively combine the first and second detector images to produce a composite molecular breast image having reduced noise compared to the first and second detector images, wherein the filter is configured to reduce noise in non-target regions and preserve contrast in target regions.