Standardization of metaiodobenzylguanidine heart to mediastinum ratio using a calibration phantom: effects of correction on normal databases and a multicentre study

• Published in: European journal of nuclear medicine and molecular imaging 2012-01, Vol.39 (1), p.113-119
• Main Authors: Nakajima, Kenichi, Okuda, Koichi, Matsuo, Shinro, Yoshita, Mitsuhiro, Taki, Junichi, Yamada, Masahito, Kinuya, Seigo
• Format: Article
• Language: English
• Subjects: 3-Iodobenzylguanidine - pharmacokinetics; Aged; Alzheimer Disease - diagnostic imaging; Alzheimer Disease - metabolism; Alzheimer's disease; Calibration; Cameras; Cardiology; Databases, Factual; Dementia disorders; Diagnosis, Differential; Heart; Hospitals; Humans; Imaging; Lewy bodies; Lewy Body Disease - diagnostic imaging; Lewy Body Disease - metabolism; Mathematical models; Mediastinum; Medical imaging; Medicine; Medicine & Public Health; Myocardium - metabolism; Neurodegenerative diseases; Nuclear Medicine; Oncology; Original Article; Orthopedics; Phantoms, Imaging; Radiology; Reference Standards; Retrospective Studies; Societies, Scientific; Standardization; Tomography, Emission-Computed, Single-Photon - instrumentation; Tomography, Emission-Computed, Single-Photon - standards
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-011-1963-1

Purpose This study was performed to demonstrate that the results obtained with a calibration phantom could be used as a tool for standardizing measurement of heart to mediastinum (H/M) ratio in cardiac metaiodobenzylguanidine (MIBG) imaging. Methods Images of the phantom containing 123 I-MIBG were acquired on the cameras in 10 hospitals (11 camera types) to determine the relationship between H/M ratios using different collimators: low-energy (LE) and medium-energy (ME)/low–medium-energy (LME) collimators. The effect of standardization on the ME-comparable H/M ratio was examined in two settings: a Japanese standard MIBG database ( n  = 62) and multicentre studies ( n  = 49). In a multicentre study, probable Alzheimer’s disease (AD, n  = 18) and probable dementia with Lewy bodies (DLB, n  = 31) were studied and standardized by the calibration phantom method. Results Linear regression equations between LE and ME collimators were obtained for the phantom study in all institutions. When the H/M ratio with an LE collimator was corrected based upon the calibration phantom, the corrected values were comparable to those obtained using ME collimators. The standard database also exhibited a normal distribution after standardization as determined by skewness and goodness-of-fit test. A mixture of the populations by LE and ME collimators showed significant separation of AD and DLB groups (F ratio = 24.9 for the late H/M), but the corrected values resulted in higher F ratios for both early and late H/M (F ratio = 34.9 for the late H/M). Conclusion Standardization of H/M ratios by the heart-chest calibration phantom method is feasible among different collimator types. This method could be practically used for multicentre comparison of H/M ratios.