[Diagnostic value of cardiac 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy in Lewy body disorders].
BACKGROUND
Lewy body disorders such as Parkinson's disease (PD) and Lewy body dementia (LBD) are associated with cardiac sympathetic denervation, which can be visualized on 123I-MIBG scintigraphy. Our objectives were to study the diagnostic value of this technique in Lewy body disorders and its relationship with PD clinical variables.


METHODS
We studied 90 patients: 51 with PD, 19 with LBD, 9 with multiple system atrophy (MSA) and 11 controls. Scintigraphy images were qualitatively evaluated and early and delayed heart-to-mediastinum ratios (HMR) were calculated. The main confounding factors (ischemic heart disease, diabetes, hypertension and drugs) were controlled by multivariate linear regression analysis. We investigated correlations between scintigraphy variables and PD variables.


RESULTS
The delayed HMR, which showed better discriminative ability was 2.03 +/- 0.32 in controls, 1.37 +/- 0.30 in PD (p<0.001 vs controls), 1.47+/-0.45 in LBD (p=0.001 vs controls) and 1.69+/-0.28 in MSA (p=0.02 vs controls; p=0.004 vs PD). This ratio was influenced by PD/LBD diagnosis (beta= -0.638; p<0.001) and to a lesser degree, by ischemic heart disease (beta= -0.244; p=0.028). Optimal cut-off value between PD/LBD and controls was 1.71 (83% sensitivity and 82% specificity). Within the PD group, those with a family history of PD/LB showed higher delayed HMR values (1.65+/-0.34 vs 1.30+/-0.24 without history; p<0.001) and proportion with normal scintigraphy (56% vs 5%; p=0.001).


CONCLUSIONS
Cardiac 123I-MIBG scintigraphy is useful in the diagnosis of Lewy body disorders, although its value in PD is conditioned by having a family history of PD.
Servicio de Neurología, Hospital Universitario Virgen de las Nieves, Granada.
F
F
Escamilla-Sevilla
M J
MJ
Pérez-Navarro
M
M
Muñoz-Pasadas
T
T
Ortega-Léon
M
M
Gallego-Peinado
D
D
Cabello-García
M
M
Gómez Río
A
A
Ortega-Moreno
C
C
Carnero-Pardo
A C
AC
Rebollo-Aguirre
A
A
Mínguez-Castellanos
D019797:3-Iodobenzylguanidine; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006321:Heart / Q000294:innervation; D006801:Humans; D020961:Lewy Body Disease / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D010300:Parkinson Disease / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D019275:Radiopharmaceuticals; D013562:Sympathectomy
D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine