Kombinierte Positronen-Emissions-Tomographie/Computertomographie (PET/CT) für die klinische Onkologie: Technische Grundlagen und Akquisitionsprotokolle

Zusammenfassung

Die kombinierte PET/CT ist eine nicht-invasive bildgebende Methode zur Darstellung anatomischer und molekularer Zusammenhänge durch eine quasi-simultane Untersuchung. Seit der Einführung des PET/CT-Prototypen im Jahr 1998 hat sich die Technologie dieser Bildgebung rasant entwickelt. Die Einführung schneller PET-Detektormaterialien in die PET/CT-Tomographie sowie die Nutzung des CT zur Schwächungskorrektur erlauben onkologische Ganzkörperuntersuchungen in weniger als 30 min. PET/CT bringt auch einen logistischen Vorteil sowohl für den Partienten als auch für den Kliniker, da beide Untersuchungen - soweit klinisch indiziert - quasi-simultan akquiriert werden können und nur ein einziger, integrierter Befund entsteht. Trotzdem gibt es eine Reihe von möglichen methodischen Fehlerquellen, vorrangig durch die CT-basierte Schwächungskorrektur, die jedoch verstanden sind und durch optimierte Akquisitionsprotokolle adressiert werden können. Mittlerweile ist das PET/CT als Bestandteil der diagnostischen Bildgebung etabliert und führt in vielen Fällen zu einer engen Zusammenarbeit der verschiedenen, aber komplementären diagnostischen und therapeutischen Disziplinen der Medizin.

Abstract

Combined PET/CT imaging is a non-invasive means of reviewing both, the anatomy and the molecular pathways of a patient during a quasi-simultaneous examination. Since the introduction of the prototype PET/CT in 1998 a rapid development of this imaging technology is being witnessed. The incorporation of fast PET detector technology into PET/CT designs and the routine use of the CT transmission images for attenuation correction of the PET allow for anato-metabolic whole-body examinations to be completed in less than 30 min. Thus, PET/CT imaging offers a logistical advantage to both, the patient and the clinicians since the two complementary exams - whenever clinically indicated - can be performed almost at the same time and a single integrated report can be created. Nevertheless, a number of pitfalls, primarily from the use of CT-based attenuation correction, have been identified and are being addressed through optimized acquisiton protocols. It is fair to say, that PET/CT has been integrated in the diagnostic imaging arena, and in many cases has led to a close collaboration between different, yet complementary diagnostic and therapeutic medical disciplines.

Schlüsselwörter

PET/CT - Onkologie - Diagnostik - Protokolle

Key words

PET/CT - oncology - diagnostics - protocols

Literatur

• 1 Antoch G, Freudenberg L S, Beyer T, Bockisch A, Debatin J F. To Enhance or Not to Enhance? ¹⁸F-FDG and CT Contrast Agents in Dual-Modality ¹⁸F-FDG PET/CT.  J Nucl Med. 2004;  45 (Suppl) 56S-65S
• 2 Antoch G, Freudenberg L S, Egelhof T. et al . Focal Tracer Uptake: A Potential Artifact in Contrast-Enhanced Dual-Modality PET/CT Scans.  J Nucl Med. 2002;  43 1339-1342
• 3 Antoch G, Kuehl H, Kanja J. et al . Dual-modality PET/CT scanning with negative oral contrast agent to avoid artifacts: Introduction and evaluation.  Radiology. 2004;  230 879-885
• 4 Antoch G, Saoudi N, Kuehl H. et al . Accuracy of whole-body PET/CT for tumor staging in solid tumors: Comparison with CT and PET in 260 patients.  Journal of Clinical Oncology. 2004;  22 4357-4361
• 5 Baum R M, Hofmann M. Nuklearmedizinische Diagnostik neuroendokriner Tumoren.  Onkologe. 2004;  6 598-610
• 6 Bendriem B D, Townsend D N. The theory and practice of 3D-PET. In: Cox PH (ed). Developments in Nuclear Medicine. Vol. 32. Kluwer Academic Publishers, Dordrecht 1998
• 7 Beyer T, Antoch G, Blodgett T. et al . Dual-modality PET/CT imaging: the effect of respiratory motion on combined image quality in clinical oncology.  European Journal of Nuclear Medicine. 2003;  30 588-596
• 8 Beyer T, Antoch G, Kuehl H, Mueller S P. Acquisition Schemes for Combined F-18-FDG-PET/CT Imaging - A European perspective. In: Czernin J et al. (eds). Atlas of PET/CT Imaging in Oncology. Springer, 2004; 30-45
• 9 Beyer T, Antoch G, Muller S. et al . Acquisition Protocol Considerations for Combined PET/CT Imaging.  J Nucl Med. 2004;  45 (Suppl 1) 25S-35S
• 10 Beyer T, Antoch G, Rosenbaum S. et al . Optimized i. v. contrast administration protocols for diagnostic PET/CT imaging.  European Radiology. 2004;  14 (Suppl 2) 422-423
• 11 Beyer T, Kinahan P E, Townsend D W. Optimization of emission and transmission scan duration in 3D whole-body PET.  IEEE Transactions in Nuclear Science. 1997;  44 2400-2407
• 12 Beyer T, Kuehl H, Stattaus J. et al . Respiration artifacts in whole-body studies with 2nd and 3rd generation PET/CT systems employing multi-row CT technology.  The Journal of Nuclear Medicine. 2004;  45 427P
• 13 Beyer T, Lechel U, Mueller S P. et al . Radiation exposure during combined whole-body FDG-PET/CT imaging.  The Journal of Nuclear Medicine. 2004;  45 P426
• 14 Beyer T, Tellmann L, Nickel I. et al . Reduced motion artifacts in the head/neck region of whole-body PET/CT studies through the use of positioning aids.  The Journal of Nuclear Medicine. 2004;  45 P428
• 15 Beyer T, Townsend D W, Brun T. et al . A combined PET/CT tomograph for clinical oncology.  Journal of Nuclear Medicine. 2000;  41 1369-1379
• 16 Bockisch A, Beyer T, Antoch G. et al . Positron emission tomography/computed tomography-imaging protocols, artifacts, and pitfalls.  Molecular Imaging and Biology. 2004;  6 188-199
• 17 Bradley J D, Perez C A, Dehdashti F, Siegel B A. Implementing Biologic Target Volumes in Radiation Treatment Planning fot Non-Small Cell Lung Cancer.  The Journal of Nuclear Medicine. 2004;  45 (Suppl 1) 96S-101S
• 18 Bruckbauer T, Casey M, Valk P E. et al .Optimizing 3D whole body acquisition for oncologic imaging on the ECAT ACCEL LSO PET system. In EANM, Naples 2001
• 19 Charron M, Beyer T, Bohnen N N. et al . Image analysis in patients with cancer studied with a combined PET and CT scanner.  Clinical Nuclear Medicine. 2000;  25 905-910
• 20 Cohade C, Osman M, Marshall L T, Wahl R L. PET-CT: accuracy of PET and CT spatial registration of lung lesions.  Eur J Nucl Med Mol Imaging. 2003;  30 721-726
• 21 Comtat C, Kinahan P E, Fessler J A. et al . Clinically feasible reconstruction of 3D whole-body PET/CT data using blurred anatomical labels.  Physics in Medicine and Biology. 2002;  47 1-20
• 22 Dahlbom M, Hoffman E J, Hoh C K. et al . Whole-body Positron Emission Tomography: Part I. Methods and Performance Characteristics.  Journal of Nuclear Medicine. 1992;  33 1191-1199
• 23 Di Filippo F, Brunken R, Neumann D. et al . Initial clinical experience with ⁸²Rb cardiac PET imaging on a PET/CT system.  The Journal of Nuclear Medicine. 2004;  45 117
• 24 Dizendorf E, Hany T F, Buck A, Schulthess G K von, Burger C. Cause and Magnitude of the Error Induced by Oral CT Contrast Agent in CT-Based Attenuation Correction of PET Emission Studies.  J Nucl Med. 2003;  44 732-738
• 25 Erdi Y E, Nehmeh S A, Pan T. et al . The CT motion quantitation of lung lesions and its impact on PET-measured SUVs.  The Journal of Nuclear Medicine. 2004;  45 1287-1292
• 26 Goerres G, Schmid D, Eyrich G. Do hardware artefacts influence the performance of head and neck PET scans in patients with oral cavity squamous cell cancer?.  Dentomaxillofacial Radiology. 2003;  32 365-371
• 27 Goerres G W, Burger C, Schwitter M R. et al . PET/CT of the abdomen: optimizing the patient breathing pattern.  European Radiology. 2003;  13 734-739
• 28 Goerres G W, Kamel E, Heidelberg T-N H. et al . PET-CT image co-registration in the thorax: influence of respiration.  European Journal of Nuclear Medicine. 2002;  29 351-360
• 29 Goerres G W, Ziegler S I, Burger C. et al . Artifacts at PET and PET/CT Caused by Metallic Hip Prosthetic Material.  Radiology. 2003;  226 577-584
• 30 Halpern B S, Dahlbom M, Quon A. et al . Impact of patient weight and emission scan time duration on PET/CT image quality and lesion detectability.  The Journal of Nuclear Medicine. 2004;  45 797-801
• 31 Hany T F, Steinert H C, Goerres G W, Buck A, Schulthess G K von. PET Diagnostic Accuracy: Improvement with In-Line PET-CT System: Initial Results.  Radiology. 2002;  225 575-581
• 32 Hapdey S, Buvat I, Carrasquillo J, Beegle C, Bacharach S. Characterization of noise induced by CT-based attenuation correction in PET/CT images.  The Journal of Nuclear Medicine. 2004;  45 413P
• 33 Hofmann M, Maecke H, Boerner A R. et al . Biokinetics and imaging with the Somatostatin receptor PET radioligand ⁶⁸Ga-DOTATOC: Preliminary data.  European Journal of Nuclear Medicine. 2001;  28 1751-1757
• 34 Holm S, Toft P, Jensen M. Estimation of the noise contributions from blank, transmission and emission scans in PET.  IEEE Transactions on Nuclear Sciences. 1996;  43 2285-2291
• 35 Hutton B F, Braun M. Software for image registration: algorithms, accuracy, efficacy.  Seminars in Nuclear Medicine. 2003;  XXXIII 180-192
• 36 Kinahan P, Hasegawa B, Beyer T. X-ray Based Attenuation Correction for PET/CT Scanners.  Seminars in Nuclear Medicine. 2003;  XXXIII 166-179
• 37 Kinahan P E, Townsend D W, Beyer T, Sashin D. Attenuation correction for a combined 3D PET/CT scanner.  Medical Physics. 1998;  25 2046-2053
• 38 LaCroix K J, Tsui B MW, Hasegawa B H, Brown J K. Investigantion of the use of X-ray CT images for attenuation correction in SPECT.  IEEE Transactions on Nuclear Science. 1994;  41 2793-2799
• 39 Lartizien C, Comtat C, Kinahan P E. et al . Optimization of Injected Dose Based on Noise Equivalent Count Rates for 2- and 3-Dimensional Whole-Body PET.  J Nucl Med. 2002;  43 1268-1278
• 40 Ling C C, Humm J, Larson S. et al . Towards multidimensional radiotherapy (MD-CRT): Biological imaging and biological conformality.  Int J Radiation Oncol Biol Phys. 2000;  47 551-560
• 41 Namdar M, Hany T, Siegrist P. et al . Improved CAD assessment using a combined PET/CT scanner.  The Journal of Nuclear Medicine. 2004;  45 117P-118P
• 42 Nehmeh S A, Erdi Y E, Ling C C. et al . Effect of Respiratory Gating on Quantifying PET Images of Lung Cancer.  J Nucl Med. 2002;  43 876-881
• 43 Nehmeh S A, Erdi Y E, Rosenzweig K E. et al . Reduction of Respiratory Motion Artifacts in PET Imaging of Lung Cancer by Respiratory Correlated Dynamic PET: Methodology and Comparison with Respiratory Gated PET.  J Nucl Med. 2003;  44 1644-1648
• 44 Pietrzyk U, Herholz K, Fink G. et al . An interactive technique for three-dimensional image registration: Validation for PET, SPECT, MRI and CT brain studies.  Journal of Nuclear Medicine. 1994;  35 2011-2018
• 45 Pietrzyk U, Herholz K, Heiss W-D. Three-dimensional alignment of functional and morphological tomograms.  Journal of Computer Assisted Tomography. 1990;  14 51-59
• 46 Schaller S, Semrbitzki O, Beyer T. et al . An algorithm for virtual extension of the CT field of measurement for application in combined PET/CT scanners.  Radiology. 2002;  225 (Suppl) 497
• 47 Schelbert H. PET/CT: Imaging function and structure. In: Czernin J (ed). JNM supplement to The Journal of Nuclear Medicine. Vol. 45. Society of Nuclear Medicine, 2004; 1S-103S
• 48 Schulthess G K von. Cost considerations regarding an integrated CT-PET system.  European Radiology. 2000;  10 (Suppl 3) S377-S380
• 49 Surti S J, Karp J S. Imaging characteristics of a 3-dimensional GSO whole-body PET camera.  The Journal of Nuclear Medicine. 2004;  45 1040-1046
• 50 Tang H R, Brown J K, Silva A JD. et al . Implementation of a combined X-ray CT scintillation camera imaging system for localizing and measuring radionuclide uptake: Experiments in phantoms and patients.  IEEE Transactions on Nuclear Science. 1999;  46 551-557
• 51 Townsend D W, Beyer T, Jerin J. et al . The ECAT ART scanner for Positron Emission Tomography: 1. Improvements in performance characteristics.  Clinical Positron Imaging. 1999;  2 5-15
• 52 Townsend D W, Beyer T, Meltzer C C. et al . The ECAT ART scanner for Positron Emission Tomography: 2. Research and clinical applications.  Clinical Positron Imaging. 1999;  2 17-30
• 53 Watson C, Casey M, Bendriem B. et al . A new method for assessing and optimizing clinical ¹⁸F-FDG whole-body PET data quality.  The Journal of Nuclear Medicine. 2003;  44 110-111
• 54 Woods R P, Cherry S R, Mazziotta J C. Rapid automated algorithm for aligning and reslicing PET images.  Journal of Computer Assisted Tomography. 1992;  16 620-633
• 55 Woods R P, Mazziotta J C, Cherry S R. MRI-PET registration with automated algorithm.  Journal of Computer Assisted Tomography. 1993;  17 536-546
• 56 Zasadny K R, Kison P V, Quint L Q, Wahl R L. Untreated lung cancer: Quantification of systematic distortion of tumor size and shape on non-attenuation-corrected 2-[Fluorine-18]fluoro-2-deoxy-D-glucose PET scans.  Radiology. 1996;  201 873-876