Diagnostic accuracy of cardiac metaiodobenzylguanidine scintigraphy in Parkinson disease.
OBJECTIVE
To estimate the diagnostic accuracy of cardiac (123)I-metaiodobenzylguanidine (MIBG) scintigram for detection of Parkinson disease.


METHODS
A cross-sectional study with index test of MIBG scintigram and reference standard of U.K. Parkinson's Disease Brain Bank Criteria was performed in 403 patients. Ratio of cardiac-to-mediastinum MIBG accumulation was determined at 20 min (early H/M) and 4 h (late H/M). Area under the receiver-operator characteristic (ROC) curve, sensitivity and specificity in detecting Parkinson disease were analyzed. Accuracy was analyzed in a subgroup of patients with disease duration of 3 years or less.


RESULTS
Area under the ROC curve was 0.89 using either early or late H/M as a diagnostic marker (95% CI 0.85-0.92 for early H/M and 0.86-0.93 for late H/M). Sensitivity and specificity were 81.3% (76.1-85.8%) and 85.0% (77.7-90.6%) for early H/M and 84.3% (79.3-88.4%) and 89.5% (83.01-94.1%) for late H/M. In the subgroup with duration of 3 years or less, the ROC curve area, sensitivity, and specificity were 0.86 (0.79-0.92), 76.0% (64.8-85.1%), and 83.9% (71.7-92.4%) for early H/M and 0.85 (0.78-0.92), 73.3% (61.9-82.9%), and 87.5% (75.9-94.8%) for late H/M.


CONCLUSIONS
Although diagnostic accuracy of cardiac MIBG scintigram is high, it is limited because of insufficient sensitivity in patients with short duration.
Sawada
H
H
Clinical Research Center, Utano National Hospital, Kyoto, Japan. sawada@unh.hosp.go.jp
Oeda
T
T
Yamamoto
K
K
Kitagawa
N
N
Mizuta
E
E
Hosokawa
R
R
Ohba
M
M
Nishio
R
R
Yamakawa
K
K
Takeuchi
H
H
Shimohama
S
S
Takahashi
R
R
Kawamura
T
T
D019797:3-Iodobenzylguanidine; D003430:Cross-Sectional Studies; D006801:Humans; D055414:Myocardial Perfusion Imaging; D010300:Parkinson Disease / Q000175:diagnosis*; D012372:ROC Curve; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine