The reproducibility of the virtual organ computer-aided analysis program for evaluating 3-dimensional power Doppler ultrasonography of diffuse thyroid disorders.
OBJECTIVE
The aim of this study was to evaluate the intra- observer and inter-observer reproducibility of 3-dimensional (3D) power Doppler ultrasonography with the virtual organ computer-aided analysis (VOCAL) program for measuring thyroid volume and vascular indices in patients with diffuse thyroid disorders.


METHODS
Patients with diffuse goiters were examined by 3D ultrasonography from August 2005 to July 2006. The parameters for vascular assessment included the vascularization index (VI), flow index (FI), vascularization-flow index (VFI), and thyroid size, and were obtained using the VOCAL program. This program used plane A and a 30 degrees rotational step. Intra-observer and inter-observer repeatability are presented as intra-class correlation coefficient (intra-CC) and inter-class correlation coefficient (inter-CC), with values >0.70 being acceptable.


RESULTS
Sixty-three patients in total were enrolled for this study, including 19 patients with simple goiter and 44 patients with autoimmune thyroid disease (AITD) (23 Graves' disease, 21 Hashimoto's thyroiditis). Thyroid volume and 3 vascular indices showed excellent reproducibility in the AITD group (intra- CC>0.9373 and inter-CC>0.8763) and its subgroups. The VI had excellent consistent reproducibility in the simple goiter group (intra-CC>0.8987 and inter-CC>0.8881), but the other parameters did not.


CONCLUSIONS
Based on this study, 3D power Doppler ultrasonography with the VOCAL program is a reliable tool for evaluating diffuse thyroid disorders due to an autoimmune process. The VI is the most reliable parameter.
Division of Endocrinology and Metabolism, China Medical University Hospital, Taichung, Taiwan. chiousc.wulily@msa.hinet.net
S-C
SC
Chiou
M-H
MH
Hsieh
H-Y
HY
Chen
J-D
JD
Lin
C-C
CC
Chen
W-H
WH
Hsu
L-B
LB
Jeng
C-T
CT
Chang
R-H
RH
Chen
T-Y
TY
Wang
W-L
WL
Haung
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D006042:Goiter / Q000000981:diagnostic imaging; D006111:Graves Disease / Q000000981:diagnostic imaging; D050031:Hashimoto Disease / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013959:Thyroid Diseases / Q000000981:diagnostic imaging*; D013961:Thyroid Gland / Q000098:blood supply; D018608:Ultrasonography, Doppler / Q000379:methods*; D014584:User-Computer Interface