Utilidad del [99m] Tc TRODAT-1 en el diagnóstico de la enfermedad de Parkinson / Utility of (99m) Tc TRODAT-1 imaging in diagnosing Parkinson's disease

Propósito de la revisión: la enfermedad de Parkinson (EP) es un trastorno degenerativo caracterizado clínicamente por presentar temblor en reposo, rigidez y bradicinesia. El propósito es determinar la utilidad de la molécula TRODAT-1 en el diagnóstico de la EP. Metodología: se realizó una búsqueda en las bases de datos: PUBMED, COCHRANE , MEDLINE , LILACS y SCIE LO en un periodo de 10 años desde enero de 1998 a enero de 2008. Se obtuvieron 26 artículos, éstos se analizaron y se seleccionaron 10, de los cuales sólo seis respondían a las necesidades del estudio, de acuerdo con los criterios de inclusión. De los seis artículos analizados, cuatro fueron clasificados como evidencia grado (+) y los dos restantes evidencia grado (-) de acuerdo con las guías NI CE. Todos los artículos revisados reportan una disminución importante en la captación del TRODAT-1 a nivel estriatal, su utilidad en el diagnóstico de EP en estadios tempranos, bajo costo y seguridad. Sólo tres reportan valores de sensibilidad y especificidad, pero su nivel de calidad no permite hacer una comparación de los mismos. Conclusiones: se propone realizar estudios de prueba diagnóstica comparados con el diagnóstico clínico de la enfermedad, que tengan un acuerdo en la forma de plantear las mediciones semicuantitativas de las unidades de captación utilizando las mismas fórmulas para hacerlos comparables (Acta Med Colomb 2010; 35: 119-125).

Purpose: Parkinson disease (PD) is a degenerative disorder. The clinical symptoms of this disease are resting tremor, rigidity and bradykinesia. The purpose of this literature review is to determine the utility of TRODAT -1 in the diagnosis of PD. A search covered PUBMED, COCHRANE, MEDLINE, LILACS and SCIELO databases, between January 1998 and January 2008. Study selection: twenty six articles were obtained with their respective abstracts. After the first review, ten of them were chosen and only six of them met the inclusion criteria. Four articles were classified as grade evidence (+) and two as grade evidence (-) according to NICE guides. All the articles reviewed report significantly decreased striatal uptake of TRODAT-1 in early PD patients, suggesting that this is a useful, safe, and inexpensive tool in the diagnosis of early PD. It was not possible to perform a meta-analysis with the chosen articles because only three of them reported sensitivity and specificity, and each of these used different criteria for their semi-quantitative analyses. This variability makes comparison of the semiquantitative uptake criteria impossible. Conclusions: establishment of a universal technique for quantitation of TRODAT-1 uptake is necessary in order to make meta-analysis viable and allow comparison of the usefulness of this agent among large numbers of patients and multiple populations (Acta Med Colomb 2010; 35: 119-125).

Application of SPM for Comparison of Striatal Dopamine Transporter Density between the Early Stage of the Parkinsonian Variant of Multiple System Atrophy and Parkinson's Disease

OBJECTIVE: Nigrostriatal dopaminergic neuronal degeneration is common to idiopathic Parkinson's disease(PD) and multiple system atrophy(MSA); although the topography of the nigral cell loss and striatal dopamine deficiency may differ. Currently, several functional neuroimaging techniques have been developed to differentiate between these two diseases. However, since the basal ganglia are usually poorly delineated in parkinsonian disorders on most functional neuroimaging techniques, most studies have failed to show the different pathologic changes among the parkinsonian disorders. In this study, we investigated alternation in regional loss of dopamine transporter binding using statistical parametric mapping(SPM) in patients with PD and the parkinsonian variant of MSA(MSA-P). METHODS: Ten PD and five MSA-P patients within 3 years of duration were studied with dual isotope brain SPECT following simultaneous injection of 370 MBq [99mTc] HMPAO and 111 MBq [123I] IPT. RESULTS: The basal ganglia were clearly visible on the fusion image, which was possible for quantitative and sta- tistical analysis. MSA-P patients showed significant loss of dopamine transporter binding in the left globus pallidus, anterior putamen and caudate nucleus in comparison to PD patients. CONCLUSION: This result may provide a useful tool to differentiate the pattern of loss of dopamine transporter bin- ding between PD and MSA-P.