RESUMEN
AIM: The aim of this study was to quantitatively evaluate the striatal uptake in 3 groups of patients: essential tremor (ET), drug-induced parkinsonism (DIP), and Parkinson disease (PD), using a voxel-based methodology and volumes of interests (VOIs) analysis. PATIENTS AND METHOD: Sixty patients from the Neurology Department Movement Disorders outpatient clinic in a tertiary hospital with I-123-FP-CIT SPECT were selected. After a clinical follow-up period of 2 years, a final clinical diagnosis of DIP was established for 20 patients (first group); 20 patients were diagnosed with ET (second group), and the third group was made up of 20 patients with a qualitatively pathologic SPECT who were diagnosed with PD.Once processed, DIP studies were spatially normalized to Montreal Neurologic Institute space and an average image was computed to create an I-123-FP-CIT SPECT template using statistical parametric mapping (SPM). Then all the I-123-FP-CIT images from all groups (DIP, ET, and PD) were registered to the new template. VOIs were defined in a digital atlas in Montreal Neurologic Institute space (caudate nucleus, putamen, and occipital cortex). Finally, mean counts were extracted from all VOIs and putamen-occipital and caudate-occipital ratios were computed. Analysis of variance tests were performed with all ratios.A SPM study of patterns evaluated the efficacy of the automated technique to determine whether the significant differences among groups corresponded to the same regions that the method purported to evaluate. RESULTS: The analysis of variance test revealed significant differences between DIP and ET as compared with PD, both in the putamen and in the caudate nucleus. There were significant differences between DIP and ET populations only in the putamen but not in the caudate.The SPM found a lower uptake in the PD group in comparison with the ET and DIP groups. Therefore, in the organic parkinsonism cases, the most significant changes in uptake decrease were found in the putamen nuclei when compared with the DIP and the ET cases. No significant changes were observed between the ET and DIP groups. CONCLUSIONS: This study provides a fairly simple, reproducible, and useful methodology to be applied in everyday practice to quantify the studies of dopamine transporters using FP-CIT.We present the different ratios for putamen and caudate nucleus for 3 different groups with FP-CIT images. We obtained an optimal discrimination threshold value between the reference population and the pathologic population for the putamen ratio.
Asunto(s)
Temblor Esencial/complicaciones , Temblor Esencial/diagnóstico por imagen , Neostriado/diagnóstico por imagen , Neostriado/patología , Trastornos Parkinsonianos/complicaciones , Trastornos Parkinsonianos/diagnóstico por imagen , Tropanos/farmacocinética , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Estadísticos , Curva ROC , CintigrafíaRESUMEN
Botulinum neurotoxin (BoNT) is an effective treatment for cervical dystonia (CD). Long-term changes of several variables, including the dose of BoNT, in these patients is largely unknown. We reviewed the clinical charts of 275 patients with CD treated with BoNT type A (BoNT-A) for at least 5 years since 1989 at ten tertiary centers. The mean dose of BoNT-A per session during the first 5 years of treatment was calculated and the appearance of resistance was noted. The dose of BoNT-A for the whole group showed a significant trend to increase over time (year 1: 180 ± 65 U; year 5: 203 ± 63 U; ANOVA: p < 0.0001). However, when we studied the evolution of the dose of BoNT-A for those patients (n = 49) first injected after 2000 (introduction of current BOTOX preparation in our country), there was no significant increase in dose (year 1: 181.8 ± 75 U; year 5: 181.7 ± 75 U; ANOVA p: ns). A total of 19 patients became secondary nonresponders; all but one of these patients began BoNT-A treatment before 2000. In summary, there is a statistically significant increase of mean dose of BoNT-A per session over time, and this could be explained by the appearance of secondary nonresponders. On the other hand, those patients initially treated after 2000 did not show any statistically significant increase in dose for 5 years. This could be explained by better experience and techniques, fewer immunogenic problems with the current BoNT-A, and also less variability of the dose per vial.
Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Fármacos Neuromusculares/uso terapéutico , Tortícolis/tratamiento farmacológico , Adulto , Análisis de Varianza , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
INTRODUCTION: The D(2) receptor is the most widely expressed dopaminergic receptor in the central nervous system, and it is present at the pre- and postsynaptic dopaminergic regions. It is mainly located in the neostriatum as well as in the globus pallidus, substantia nigra, cerebral cortex, thalamus, etc. The objective of this study was to analyze qualitatively and quantitatively the distribution pattern of the postsynaptic dopamine receptors through SPECT with iodobenzamide (IBZM) in patients with parkinsonism and to determine the benefit of this imaging technique in the differential diagnosis of the parkinsonian syndromes. MATERIALS: A total of 26 patients with clinical and imaging (Iodine-123 fluoropropyl-carbomethoxy-3 beta-(4-iodophenyltropane) [FP-CIT]) diagnostics of parkinsonism, to all of which a study of postsynaptic D(2) receptors with IBZM was made, were retrospectively reviewed. Of total, 12 patients were male (42.85%). The average age was 73 years old (range, 64-83 years). The patients were imaged using SPECT 2 hours after administration of I-123 Iolopride (IBZM) and their images were evaluated qualitatively and quantitatively. To measure the relative density of the D(2) receptors, the studies were registered to a common space in which the structures to be analyzed were delimited over a RM template. Caudate/frontal (C/FI) and putamen/frontal (P/FI) activity indexes were obtained. RESULTS: Of total, 10 patients presented normal IBZM uptake (C/FI of 1.23 + or - 0.13; P/FI of 1.53 + or - 0.11). The 16 studies listed as abnormal were divided into 2 degrees: (I) appearance of thalamic activity with preserved striatal uptake and (II) thalamus and frontal increased uptake with decrease of striatal activity. In the patients with abnormal patterns, the region that showed a greater reduction of uptake was the putamen (P/FI of 1.1 + or - 0.07 for degree 1, P < 0.05 and P/FI of 1.25 + or - 0.19 for degree 2, P < 0.001). For the differential diagnosis of Parkinson disease in relation to the atypical parkinsonisms, the sensitivity was 68.4% (confidence interval, 51.9-87.6) and the specificity was 57.1% (confidence interval, 20.2-88.2). The patients with Parkinson disease with longer evolution times showed a decrease of D(2) activity (3/7). CONCLUSION: The appearance of thalamic activity may be an early indicator of a decrease of D(2) striatal receptors in atypical parkinsonisms and in patients with long-term Parkinson disease.