title: The accuracy of quantitative parameters in (99m) Tc-MAG3 dynamic renography: a national audit based on virtual image data.
abstract: Assessment of image analysis methods and computer software used in (99m) Tc-MAG3 dynamic renography is important to ensure reliable study results and ultimately the best possible care for patients. In this work, we present a national multicentre study of the quantification accuracy in (99m) Tc-MAG3 renography, utilizing virtual dynamic scintigraphic data obtained by Monte Carlo-simulated scintillation camera imaging of digital phantoms with time-varying activity distributions. Three digital phantom studies were distributed to the participating departments, and quantitative evaluation was performed with standard clinical software according to local routines. The differential renal function (DRF) and time to maximum renal activity (Tmax ) were reported by 21 of the 28 Swedish departments performing (99m) Tc-MAG3 studies as of 2012. The reported DRF estimates showed a significantly lower precision for the phantom with impaired renal uptake than for the phantom with normal uptake. The Tmax estimates showed a similar trend, but the difference was only significant for the right kidney. There was a significant bias in the measured DRF for all phantoms caused by different positions of the left and right kidney in the anterior-posterior direction. In conclusion, this study shows that virtual scintigraphic studies are applicable for quality assurance and that there is a considerable uncertainty associated with standard quantitative parameters in dynamic (99m) Tc-MAG3 renography, especially for patients with impaired renal function.
authors.affiliation: Department of Medical Radiation Physics, Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: Gustav
authors.initials: G
authors.lastname: Brolin
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Edenbrandt
authors.affiliation: Department of Medical and Health Sciences, Division of Cardiovascular Medicine/Section of Clinical Physiology and Nuclear Medicine, Linköping University, Linköping, Sweden.
authors.forename: Göran
authors.initials: G
authors.lastname: Granerus
authors.affiliation: Department of Radiation Physics/Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Olsson
authors.affiliation: EQUALIS AB, Uppsala, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Afzelius
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Agneta
authors.initials: A
authors.lastname: Gustafsson
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Cathrine
authors.initials: C
authors.lastname: Jonsson
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Lund, Sweden.
authors.forename: Jessica
authors.initials: J
authors.lastname: Hagerman
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Clinical Physiology, Central Hospital, Karlstad, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Johansson
authors.affiliation: EQUALIS AB, Uppsala, Sweden.|Department of Radiation Sciences, Diagnostic Radiology, Umeå University, Umeå, Sweden.
authors.forename: Katrine
authors.initials: K
authors.lastname: Riklund
authors.affiliation: Department of Medical Radiation Physics, Clinical Sciences Lund, Lund University, Lund, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Ljungberg
mesh_terms: D003198:Computer Simulation; D005240:Feasibility Studies; D005260:Female; D015902:Gamma Cameras; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007668:Kidney / Q000000981:diagnostic imaging* / Q000503:physiopathology; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D009010:Monte Carlo Method; D015588:Observer Variation; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D011866:Radioisotope Renography / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D019275:Radiopharmaceuticals / Q000008:administration & dosage*; D015203:Reproducibility of Results; D012984:Software; D013548:Sweden; D017263:Technetium Tc 99m Mertiatide / Q000008:administration & dosage*
chemical_list: D019275:Radiopharmaceuticals; D017263:Technetium Tc 99m Mertiatide
keywords: 99mTc-MAG3; Monte Carlo imaging simulations; differential renal function; digital phantoms; dynamic renography; quality assurance