title: SPECT/CT: an update on technological developments and clinical applications.
abstract: Functional nuclear medicine imaging with single-photon emission CT (SPECT) in combination with anatomical CT has been commercially available since the beginning of this century. The combination of the two modalities has improved both the sensitivity and specificity of many clinical applications and CT in conjunction with SPECT that allows for spatial overlay of the SPECT data on good anatomy images. Introduction of diagnostic CT units as part of the SPECT/CT system has also potentially allowed for a more cost-efficient use of the equipment. Most of the SPECT systems available are based on the well-known Anger camera principle with NaI(Tl) as a scintillation material, parallel-hole collimators and multiple photomultiplier tubes, which, from the centroid of the scintillation light, determine the position of an event. Recently, solid-state detectors using cadmium-zinc-telluride became available and clinical SPECT cameras employing multiple pinhole collimators have been developed and introduced in the market. However, even if new systems become available with better hardware, the SPECT reconstruction will still be affected by photon attenuation and scatter and collimator response. Compensation for these effects is needed even for qualitative studies to avoid artefacts leading to false positives. This review highlights the recent progress for both new SPECT cameras systems as well as for various data-processing and compensation methods.
authors.affiliation: 1 Department of Medical Radiation Physics, Lund University, Lund, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Ljungberg
authors.affiliation: 2 Division of Nuclear Medicine, Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA.
authors.forename: P Hendrik
authors.initials: PH
authors.lastname: Pretorius
mesh_terms: D001859:Bone Neoplasms / Q000000981:diagnostic imaging; D002104:Cadmium; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D064847:Multimodal Imaging; D055414:Myocardial Perfusion Imaging; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging; D011829:Radiation Dosage; D013691:Tellurium; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation; D014057:Tomography, X-Ray Computed / Q000295:instrumentation; D015032:Zinc
chemical_list: C474490:CdZnTe; D002104:Cadmium; D015032:Zinc; D013691:Tellurium