The Feasibility of Using CT-Guided ROI for Semiquantifying Striatal Dopamine Transporter Availability in a Hybrid SPECT/CT System
Table 1
Striatal, caudate, and putamen BPND from manual SPECT, CT-guided, and MRI-guided ROIs methods; the intra- and interobserver concordance correlation coefficients, Bland-Altman biases, and limits of agreement of manual SPECT and CT-guided ROI methods.
Striatal BPND
Caudate BPND
Putamen BPND
Manual SPECT ROI
Intraobserver (observer A)
First analysis
0.46 ± 0.24
0.55 ± 0.26
0.42 ± 0.24
Second analysis
0.48 ± 0.26
0.58 ± 0.29
0.38 ± 0.26
CCC
0.96
0.96
0.93
95% CI of CCC
0.93–0.98
0.94–0.98
0.89–0.96
Bias (mean difference)
−0.03
−0.03
0.03
Limits of agreement
−0.16, 0.10
−0.16, 0.11
−0.13, 0.20
Interobserver*
Observer B analysis
0.39 ± 0.23
0.48 ± 0.22
0.36 ± 0.24
CCC
0.89
0.89
0.88
95% CI of CCC
0.82–0.93
0.83–0.93
0.80–0.93
Bias (mean difference)
0.07
0.07
0.05
Limits of agreement
−0.11, 0.25
−0.11, 0.25
−0.16, 0.27
CT-guided ROI
Intraobserver (observer A)
First analysis
0.49 ± 0.25
0.54 ± 0.25
0.46 ± 0.27
Second analysis
0.48 ± 0.25
0.52 ± 0.26
0.46 ± 0.27
CCC
0.98
0.97
0.97
95% CI of CCC
0.97–0.99
0.94–0.98
0.95–0.98
Bias (mean difference)
0.01
0.02
0.01
Limits of agreement
−0.08, 0.11
−0.11, 0.14
−0.12, 0.13
Interobserver*
Observer B analysis
0.48 ± 0.26
0.56 ± 0.27
0.45 ± 0.28
CCC
0.97
0.95
0.96
95% CI of CCC
0.95–0.98
0.92–0.97
0.94–0.98
Bias (mean difference)
0.01
−0.02
0.02
Limits of agreement
−0.12, 0.13
−0.18, 0.13
−0.13, 0.16
MRI-guided ROI
0.46 ± 0.25
0.53 ± 0.26
0.43 ± 0.25
BPND: nondisplaceable binding potential; SPECT: single photon emission computed tomography; ROI: region of interest; CCC: concordance correlation coefficient; CI: confidence interval; CT: computed tomography *Interobserver analysis was compared with observer A’s first analysis.
