Development and validation of a direct-comparison method for cardiac 123I-metaiodobenzylguanidine washout rates derived from late 3-hour and 4-hour imaging
Development and validation of a direct-comparison method for cardiac 123I-metaiodobenzylguanidine washout rates derived from late 3-hour and 4-hour imaging
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DOI：
10.1007/s00259-015-3173-8
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发表时间：
2016-02-01
影响因子：
9.1
通讯作者：
Kinuya, Seigo
中科院分区：
文献类型：
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作者：
Okuda, Koichi;Nakajima, Kenichi;Kinuya, Seigo
目的应用洗出率（WR）评价123-间碘苄胍（MIBG）心肌显像的交感神经支配。然而，WR根据早期和晚期MIBG扫描之间的时间而变化。晚期扫描在注射MIBG后3或4小时进行。本研究的目的是直接比较WR在3小时（WR 3 h）和WR在4小时（WR4h.Methods），我们假设心脏计数将线性减少之间的3小时和4小时的扫描。生成了两个时间点心脏计数的线性回归模型。我们共招募了96名患者，他们在早期（15分钟）和晚期（3小时和4小时）接受了平面I-123-MIBG血管造影。患者被随机分为两组：模型创建组（组1）和临床验证组（组2）。测量15分钟（计数（早期））、3小时（计数（3 h））和4小时（计数（4 h））时的心脏计数。结果在第1组中，实际心脏计数（4 h）/计数（early）与计数（3 h）/计数（early）呈高度显著相关（r = 0.979）;在第2组中，平均估计计数（4小时）为92.8 +/- 31.9，该值与实际计数（4小时）（91.9 +/- 31.9）之间无显著差异。Bland-Altman分析显示偏倚较小，为-0.9，95%一致性限值为-6.2和+4.3。使用估计的心脏计数（4 h）计算的WR 4 h与实际WR 4 h相当（24.3 +/-9.6% vs. 25.1 +/-9.7%，p = ns）。Bland-Altman相关分析及组内相关系数分析显示，估算的WR 4 h与实际WR 4 h具有良好的一致性。结论利用计数（早期）和计数（3 h）建立的线性回归模型能够准确估算心脏计数（4 h）。此外，使用估计计数（4 h）数学计算的WR 4 h与实际WR 4 h相当。
Purpose The washout rate (WR) has been used in I-123-metaiodobenzylguanidine (MIBG) imaging to evaluate cardiac sympathetic innervation. However, WR varies depending on the time between the early and late MIBG scans. Late scans are performed at either 3 or 4 hours after injection of MIBG. The aim of this study was to directly compare the WR at 3 hours (WR3h) with the WR at 4 hours (WR4h).Methods We hypothesized that the cardiac count would reduce linearly between the 3-hour and 4-hour scans. A linear regression model for cardiac counts at two time-points was generated. We enrolled a total of 96 patients who underwent planar I-123-MIBG scintigraphy early (15 min) and during the late phase at both 3 and 4 hours. Patients were randomly divided into two groups: a model-creation group (group 1) and a clinical validation group (group 2). Cardiac counts at 15 minutes (count(early)), 3 hours (count(3h)) and 4 hours (count(4h)) were measured. Cardiac count(4h) was mathematically estimated using the linear regression model from count(early) and count(3h).Results In group 1, the actual cardiac count(4h)/count(early) was highly significantly correlated with count(3h)/count(early) (r = 0.979). In group 2, the average estimated count(4h) was 92.8 +/- 31.9, and there was no significant difference between this value and the actual count(4h) (91.9 +/- 31.9). Bland-Altman analysis revealed a small bias of -0.9 with 95 % limits of agreement of -6.2 and +4.3. WR4h calculated using the estimated cardiac count(4h) was comparable to the actual WR4h (24.3 +/- 9.6 % vs. 25.1 +/- 9.7 %, p = ns). Bland-Altman analysis and the intraclass correlation coefficient showed that there was excellent agreement between the estimated and actual WR4h.Conclusion The linear regression model that we used accurately estimated cardiac count(4h) using count(early) and count(3h). Moreover, WR4h that was mathematically calculated using the estimated count(4h) was comparable to the actual WR4h.