Nonuniformity intrinsic flood artifact caused by point-source syringe needle.

The purpose of this study was to investigate the cause of a nonuniformity artifact seen on an intrinsic flood. Methods: Intrinsic floods were acquired on three different cameras using a point source in a 1-cc syringe, with and without a needle attached. Floods were obtained with the syringe placed perpendicular and parallel to the camera face. Results: A nonuniformity artifact was evident if a syringe with a needle was placed perpendicular to the crystal face. Conclusion: If a syringe is used as a point source during the acquisition of an intrinsic quality control flood, the needle should not be placed perpendicular to the camera face.