Reducing the small-heart effect in pediatric
gated myocardial perfusion single-photon
emission computed tomography
Hiroto Yoneyama, PhD,
Kenichi Nakajima, MD,
Koichi Okuda, PhD,
Shinro Matsuo, MD,
Masahisa Onoguchi, PhD,
Seigo Kinuya, MD,
Lars Edenbrandt, MD, PhD
Department of Radiological Technology, Kanazawa University Hospital, Kanazawa, Japan
Department of Nuclear Medicine, Kanazawa University Hospital, Kanazawa, Japan
Department of Physics, Kanazawa Medical University, Kanazawa, Japan
Department of Health Science, Graduate School of Medical Science, Kanazawa University,
Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg,
Received Nov 7, 2015; accepted Apr 10, 2016
Background. We compared two reconstruction algorisms and two cardiac functional
evaluation software programs in terms of their accuracy for estimating ejection fraction (EF) of
small hearts (SH).
Methods. The study group consisted of 66 pediatric patients. Data were reconstructed using
a ﬁltered back projection (FBP) method without the resolution correction (RC) and an iterative
method based on an ordered subset expectation maximization (OSEM) algorithm with the RC.
EF was evaluated using two software programs of quantitative gated single-photon emission
computed tomography (SPECT) (QGS) and cardioREPO. We compared the EF of gated
myocardial perfusion SPECT to echocardiographic measurement (Echo).
Results. Forty-eight of 66 patients had an end-systolic volume < 20 mL which was used as
the criterion for being included in the SH group, and the SH effect led to an overestimation of
EF. While signiﬁcant differences were observed between Echo (66.9 ± 5.0%) and QGS-FBP
without RC (76.9 ± 8.4%, P < .0001), QGS-OSEM with RC (76.6 ± 8.6%, P < .0001), and
cardioREPO-FBP without RC (72.1 ± 10.0%, P 5 .0011), no signiﬁcant difference was
observed between Echo and cardioREPO-OSEM with RC (67.4 ± 6.1%) in SH group.
Conclusions. In pediatric gated myocardial perfusion SPECT, the SH effect can be sig-
niﬁcantly reduced when an OSEM algorithm is used with RC in combination with the speciﬁc
cardioREPO algorithm. (J Nucl Cardiol 2017;24:1378–88.)
Key Words: Ejection fraction
Æ small-heart effect Æ resolution correction Æ quantitative gated
Electronic Supplementary Material The online version of this
article (doi:10.1007/s12350-016-0518-z) contains supplementary
material, which is available to authorized users.
Reprint requests: Hiroto Yoneyama, PhD, Department of Radiological
Technology, Kanazawa University Hospital, 13-1 Takara-machi,
Kanazawa 920-8641, Japan; email@example.com
Copyright Ó 2016 American Society of Nuclear Cardiology.