title: Review of the linogram and sinogram: an easy way to detect off-peak artifacts in myocardial perfusion SPECT.
abstract: The correct energy window setting and a stable photopeak position are crucial for good data acquisition. We report a patient whose myocardial perfusion SPECT images showed mildly irregular radiotracer uptake when the patient was prone but not when the patient was supine. Review of the sinogram showed clear interruptions in the sinusoidal shape of the raw data when the patient was prone. Detailed technical evaluation revealed that the artifact was caused by an unstable photopeak position due to malfunction of a power supply board of the gamma-camera. This case emphasizes the importance of reviewing the sinogram display and raw data to assess the integrity of data acquisition and to reveal any potential technical problems such as a spontaneous shift of the photopeak.
authors.affiliation: Department of Nuclear Medicine, Emam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mommennezhad
authors.forename: Seyed Rasoul
authors.initials: SR
authors.lastname: Zakavi
authors.forename: Ramin
authors.initials: R
authors.lastname: Sadeghi
authors.forename: Vahid Reza Dabbagh
authors.initials: VR
authors.lastname: Kakhki
mesh_terms: D016477:Artifacts; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008875:Middle Aged; D055420:Perfusion Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology