(123) I]FP-CIT-SPECT asymmetry index to differentiate Parkinson's disease from vascular parkinsonism

Contrafatto D, Mostile G, Nicoletti A, Dibilio V, Raciti L, Lanzafame S, Luca A, Distefano A, Zappia M. [¹²³I]FP‐CIT‐SPECT asymmetry index to differentiate Parkinson’s disease from vascular parkinsonism.
Acta Neurol Scand: 2012: 126: 12–16.
© 2011 John Wiley & Sons A/S. Objectives – Differential diagnosis between vascular parkinsonism (VP) and Parkinson’s Disease (PD) is often difficult, due to the overlap in clinical presentation and the lack of specificity at neuroimaging. Aim of the study was to identify a possible reliable marker at SPECT imaging useful to distinguish the two conditions. Material and methods – We studied 20 PD, 20 VP and 20 essential tremor (ET) patients as control group, who had undergone a cerebral [¹²³I] FP‐CIT SPECT. A semiquantitative analysis was performed on DaTSCAN SPECT imaging and to establish the degree of asymmetry of the ligand uptake the Striatal Asymmetry Index (SAI) was used. Results – The binding of the ligand in the most affected side resulted significantly lower in VP than in ET patients but higher compared to PD patients. SAI was significantly higher in PD compared to VP (P < 0.001) and ET (P < 0.001) groups. We found that a cut‐off of SAI greater than 14.08 could differentiate PD from VP with a 100% specificity and a 50% sensitivity. Conclusions – SAI detected using [¹²³I]FP‐CIT SPECT can be used to differentiate VP and PD with a good degree of certainty.     

Differences in nigro‐striatal impairment in clinical variants of early Parkinson’s disease: evidence from a FP‐CIT SPECT study

Introduction: In idiopathic Parkinson’s disease (PD), two different clinical phenotypes are usually distinguished: a tremor dominant variant (TD) and an akinetic‐rigid type (ART). TD patients are characterized by a slower disease progression and a minor cognitive impairment. Striatal density of DAT, as quantified by FP‐CIT SPECT, has been reported to correlate with rigidity and akinesia but not with tremor. Objective: To evaluate FP‐CIT uptake in TD and ART phenotypes. Methods: We retrospectively evaluated from our database the pre‐synaptic nigro‐striatal function of 24 patients with TD‐PD and 38 patients with ART‐PD who underwent a FP‐CIT SPECT within 1 year from disease onset. Results: Disease duration, age at the time of SPECT scan and disease severity as measured with Unified Parkinson’s Disease Rating scale part III (UPDRS III) were not statistically different between the two groups. Putamen contralateral to the most clinically affected side showed a lower FP‐CIT uptake in ART patients compared to TD patients. No statistically significant differences emerged when considering bilateral caudate and ipsilateral putaminal uptake, as well as asymmetry indices and caudate/putamen ratios. FP‐CIT contralateral putaminal uptake correlated with the severity of rigidity and hypokinesia but not with tremor. Conclusions: These data suggest that other neurotransmitter systems apart from the nigro‐striatal dopaminergic system are involved in the generation of Parkinsonian tremor, and they are consistent with previous evidence of a lack of correlation between tremor severity and FP‐CIT uptake. Putaminal relative sparing in TD patients could partially explain the slower disease progression reported in this PD phenotype.     

Midbrain serotonin transporters in de novo and L‐DOPA‐treated patients with early Parkinson’s disease – a [123I]‐ADAM SPECT study

Background: Dopaminergic availability is known to linearly decline in Parkinson’s disease (PD). In contrast, temporal characteristics of serotonergic markers like the serotonin transporter (SERT) in relation to clinical staging of PD and dopaminergic cell loss are less clear. This study investigated SERT availability using [¹²³I]‐ADAM and single‐photon emission tomography (SPECT) in drug‐naive, de novo patients, i.e., in a PD stage where dopaminergic decline starts to lead to the occurence of the characteristic motor symptoms. Methods: Nine de novo patients with PD and 9 age‐matched healthy controls were studied. Measurements were repeated after 3 months of levodopa treatment in patients with PD, and dopaminergic transporter (DAT) binding was examined at baseline using [¹²³I]‐FP‐CIT SPECT. Results: No alterations of SERT availability were found between groups, and neither correlation between SERT and DAT nor effects of levodopa treatment on SERT was found in patients with PD. Conclusions: These preliminary findings indicate that midbrain SERT is preserved in unmedicated patients at this early stage of PD, supporting the view that serotonergic decline temporally follows dopaminergic cell loss.     

Striatal dopamine transporter imaging correlates with depressive symptoms and tower of London task performance in Parkinson's disease

We studied whether the ¹²³I‐FP‐CIT uptake in the striatum correlates with depressive symptoms and cognitive performance in patients with Parkinson's disease (PD). Twenty patients with PD without major depression and/or dementia (mean age 61.7 ± 12.7 years) underwent the ¹²³I‐FP‐CIT SPECT. Depressive symptoms and cognitive performance were assessed in the ON state. The ratios of striatal to occipital binding for the entire striatum, putamina, and putamen to the caudate (put/caud) index were calculated in the basal ganglia. The association between neuropsychiatric measures and dopamine transporter (DAT) availability was calculated; multiple regression analysis was used to assess association with age and disease duration. We found significant correlations between Montgomery and Asberg Depression Rating Scale (MARDS) and Tower of London (TOL) task scores and ¹²³I‐FP‐CIT uptake in various striatal ROIs. Multiple regression analysis confirmed the significant relationship between TOL performance and put/caud ratio (P = 0.001) and to age (P = 0.001), and between MADRS and left striatal (P = 0.005) and putaminal DAT availability (P = 0.003). Our pilot study results demonstrate that imaging with ¹²³I‐FP‐CIT SPECT appears to be sensitive for detecting dopaminergic deficit associated with mild depressive symptoms and specific cognitive dysfunction in patients with PD, yet without a current depressive episode and/or dementia. © 2008 Movement Disorder Society     

Residual striatal dopaminergic nerve terminals in very long‐standing Parkinson's disease: A single photon emission computed tomography imaging study

Molecular imaging studies of Parkinson's disease (PD) progression mostly focus on the first 5 years after disease onset, demonstrating rapid initial nigrostriatal neuronal loss. The fate of residual functional dopaminergic nerve terminals in patients with long‐standing PD has not yet been specifically explored. Therefore, we performed [¹²³I]‐FP‐CIT single photon emission computed tomography (SPECT) in 15 patients with very long‐standing PD (mean disease duration 20.6 ± 6.3 years). Measurable uptake of [¹²³I]‐FP‐CIT was still detected in the striata of all patients. As seen in early stages, reduction of tracer uptake in the putamen was more prominent than in the caudate nucleus. Asymmetry in tracer uptake between the two putamen and caudate nuclei was preserved. These findings indicate that degeneration of dopaminergic neurons in PD is not total even after many years of illness. Data should be considered in exploring underlying causes of progressive loss of nigrostriatal dopaminergic neurons and development of future novel dopaminergic therapeutic strategies in PD. © 2010 Movement Disorder Society     

[123I]FP‐CIT SPET imaging in drug‐induced Parkinsonism

We assessed the status of dopamine nerve terminals in patients treated with dopamine receptor blocking agents (DRBAs) who had developed drug‐induced parkinsonism (DIP). We performed [¹²³I]FP‐CIT SPET in 32 consecutive patients who were on DRBAs for at least 6 months and developed extrapyramidal signs. The UPDRS‐III was used to assess clinical severity. Twenty‐six age‐ and sex‐matched healthy subjects served as control group. Putamen [¹²³I]FP‐CIT SPET binding was reduced in 14 and normal in the remaining 18 patients. There was no difference between the two groups for age, duration of DRBAs treatment, UPDRS III, tremor, rigidity, and bradykinesia subscores for upper and lower limbs. Conversely, symmetry of parkinsonian signs and presence bucco‐linguo‐masticatory dyskinesias were more frequent in individuals with normal tracer binding. Imaging of the dopamine transporter may help to identify subjects with DIP secondary to a loss of dopamine nerve terminals. © 2008 Movement Disorder Society     

Head‐to‐head comparison of 18F‐FP‐CIT and 123I‐FP‐CIT for dopamine transporter imaging in patients with Parkinson's disease: A preliminary study

¹²³I‐FP‐CIT and ¹⁸F‐FP‐CIT are radiotracers which are widely used to diagnose Parkinson's disease (PD). However, to our knowledge, no studies to date have made head‐to‐head comparisons between ¹²³I‐FP‐CIT and ¹⁸F‐FP‐CIT. Therefore, in this study, ¹²³I‐FP‐CIT SPECT/CT was compared with ¹⁸F‐FP‐CIT PET/CT in the same cohort of subjects. Patients with PD and essential tremor (ET) underwent ¹²³I‐FP‐CIT SPECT/CT and ¹⁸F‐FP‐CIT PET/CT. Visual and semiquantitative analyses were conducted. The specific binding ratio (SBR) and putamen to caudate ratio (PCR) were compared between subjects who underwent ¹²³I‐FP‐CIT SPECT/CT and ¹⁸F‐FP‐CIT PET/CT. Visual analysis showed that the striatal uptake of both radiotracers was decreased in the PD group, whereas striatal uptake was intact in the ET group. The SBR between ¹²³I‐FP‐CIT SPECT/CT and ¹⁸F‐FP‐CIT PET/CT showed a positive correlation (r = .78, p < .01). However, the mean SBRs on ¹⁸F‐FP‐CIT PET/CT were higher than those on ¹²³I‐FP‐CIT SPECT/CT (2.19 ± .87 and 1.22 ± .49, respectively; p < .01). The PCRs in these two modalities were correlated with each other (r = .71, p < .01). The mean PCRs on ¹⁸F‐FP‐CIT PET/CT were not significantly higher than those on ¹²³I‐FP‐CIT SPECT/CT (1.31 ± .19 and 0.98 ± .06, respectively; p = .06). These preliminary results indicate that the uptake of both ¹²³I‐FP‐CIT and ¹⁸F‐FP‐CIT was decreased in the PD group when compared with the ET controls. Visual analyses using both methods did not affect the diagnostic accuracy in this study. However, semiquantitative analysis indicated a better contrast of ¹⁸F‐FP‐CIT PET/CT relative to ¹²³I‐FP‐CIT SPECT/CT.     

Dopaminergic deficit is not the rule in orthostatic tremor

Involvement of the dopaminergic system in orthostatic tremor is controversial. The aim of this study was to detect possible dopaminergic denervation in primary orthostatic tremor (OT). Twelve consecutive patients with a firm diagnosis of primary orthostatic tremor were compared with age‐matched normal controls. All the patients had a neurological examination, surface polymyography, and quantification of striatal dopamine transporters with ¹²³I‐FP‐CIT SPECT imaging. There was no significant difference in ¹²³I‐FP‐CIT SPECT findings between controls and patients with OT. Longstanding primary orthostatic tremor is not necessarily associated with ¹²³I‐FP‐CIT SPECT abnormalities, as 8 of our patients had more than a 10‐year history of OT. Primary orthostatic tremor without dopaminergic denervation remains a valid entity, although representing only a subtype of high‐frequency OT. A new role may emerge for ¹²³I‐FP‐CIT SPECT in distinguishing between patients whose symptoms will be restricted to OT throughout the disease course and patients at an increased risk of developing PD. © 2008 Movement Disorder Society     

123I]beta-CIT SPECT distinguishes vascular parkinsonism from Parkinson's disease.

We investigated whether [(123)I]-beta-CIT and single-photon emission computed tomography (SPECT) imaging distinguishes patients with clinically suspected vascular parkinsonism (VP) from patients with idiopathic Parkinson's disease (PD). [(123)I]beta-CIT SPECT is a sensitive marker of dopaminergic degeneration, and the degree of striatal binding reduction in PD correlates with disease severity. Thirteen patients who fulfilled rigid clinical criteria for VP (mean +/- S.D.: age, 76.5 +/- 5.3 years; disease duration, 3.6 +/- 2.8 years), 20 PD patients (age, 66.2 +/- 9.5 years; disease duration, 4.3 +/- 2.7 years), and 30 healthy persons (age, 44.6 +/- 19.2 years) underwent [(123)I]beta-CIT SPECT imaging. Age-corrected striatal beta-CIT binding was reduced on average by 40.8% in PD but was near normal in the VP group (mean reduction, 1.2%). This difference was statistically significant (Z = 4.68; P < 0.001). The left-right asymmetry of striatal beta-CIT binding was significantly increased in the PD group compared with normal controls and the VP group (F(2) = 17.4, P <0.001). Moreover, putamen-caudate nucleus ratios were significantly reduced in PD compared with both VP patients and healthy controls (F(2) = 65.5, P < 0.001). Whole striatal beta-CIT binding was more than one standard deviation above the mean PD values in all but one of the individual VP patients. Our findings suggest that the presynaptic dopaminergic deficits seen in PD are absent in most patients with VP. [(123)I]beta-CIT SPECT imaging may be useful to help distinguish between PD and VP patients during life.     

Functional brain imaging in pure akinesia with gait freezing: [18F] FDG PET and [18F] FP‐CIT PET analyses

Pure akinesia with gait freezing (PAGF) has characteristic features, including freezing of gait and prominent speech disturbance without rigidity or tremor. The purpose of this study was to investigate changes in brain glucose metabolism and presynaptic dopaminergic function in PAGF. By using [¹⁸F] fluorodeoxyglucose (FDG) PET, 11 patients with PAGF were compared with 14 patients with probable progressive supranuclear palsy (PSP), 13 patients with Parkinson's disease (PD), and 11 normal controls. [¹⁸F] N‐(3‐fluoropropyl)‐2β‐carbon ethoxy‐3β‐(4‐iodophenyl) nortropane (FP‐CIT) PET was performed in 11 patients with PAGF and with 10 normal controls. The PAGF patients showed decreased glucose metabolism in the midbrain when compared with normal controls. PSP patients showed a similar topographic distribution of glucose hypometabolism with additional areas, including the frontal cortex, when compared with normal controls. The FP‐CIT PET findings in patients with PAGF revealed severely decreased uptake bilaterally in the basal ganglia. These findings suggest that both PAGF and PSP may be part of the same pathophysiologic spectrum of disease. However, the reason why PAGF manifests clinically in a different manner needs to be further elucidated. © 2008 Movement Disorder Society     

Parkinson's disease is overdiagnosed clinically at baseline in diagnostically uncertain cases: A 3‐year European multicenter study with repeat [123I]FP‐CIT SPECT

Overdiagnosis of Parkinson's disease (PD) is suggested by specialist review of community diagnosis, and in postmortem studies. In specialist centers 4 to 15% of patients entered into clinical trials as early PD do not have functional imaging support for a PD diagnosis. In a European multicenter, prospective, longitudinal study, we compared clinical diagnosis with functional SPECT imaging using [¹²³I]FP‐CIT (DaTSCAN?, GE Healthcare). Repeat observations were performed over 3 years in patients with tremor and/or parkinsonism in whom there was initial diagnostic uncertainty between degenerative parkinsonism and nondegenerative tremor disorders. Video‐recording of clinical features was scored independently of functional imaging results by two blinded clinicians at 36 months (= gold standard clinical diagnosis). Three readers, unaware of the clinical diagnosis, classified the images as normal or abnormal by visual inspection. The main endpoint was the sensitivity and specificity of SPECT imaging at baseline compared with the gold standard. In 99 patients completing the three serial assessments, on‐site clinical diagnosis overdiagnosed degenerative parkinsonism at baseline in diagnostically uncertain cases compared with the gold standard clinical diagnosis (at 36 months), the latter giving a sensitivity of 93% and specificity of 46%. The corresponding baseline [¹²³I]FP‐CIT SPECT results showed a mean sensitivity of 78% and a specificity of 97%. Inter‐reader agreement for rating scans as normal or abnormal was high (Cohen's = 0.94–0.97). © 2008 Movement Disorder Society     

Vascular parkinsonism: a distinct, heterogeneous clinical entity

OBJECTIVES: The aim of this study was to define the symptoms and signs of suspected vascular parkinsonism (VP) which is still a debatable concept. MATERIAL AND METHODS: Patients with parkinsonism were grouped into patients with suspected VP and Parkinson's disease (PD) after other causes for secondary parkinsonism, and parkinsonism-plus syndromes were excluded. The clinical features of 16 patients with suspected VP to those of 50 diagnosed with PD were compared. All patients were assessed using unified Parkinson's disease rating scale (UPDRS) and all had cerebral MRIs. RESULTS: Patients with VP had significantly older onset age and shorter duration of disease with gait disorder as the most frequent initial symptom. All PD patients had satisfactory response to levodopa treatment, whereas only 38% VP patients had satisfactory response to levodopa treatment. Vascular risk factors were more common in VP (81%) than PD (32%). Postural instability, freezing, gait disturbance, pyramidal signs, and postural tremor were significantly more prevalent in patients with VP than in PD. In VP patients these features were more prominent in the lower limbs. Twenty-five percent had acute onset VP. All patients with VP had ischemic lesions, mainly in subcortical white matter, to a lesser extent basal ganglia and brainstem, in their cerebral MRIs, while 70% of PD patients had normal MRIs. CONCLUSION: The differences in the clinical features support the concept that VP is a distinct clinical entity with heterogeneous clinical, MRI, and possibly pathophysiological features.     

Combination of dopamine transporter and D2 receptor SPECT in the diagnostic evaluation of PD, MSA, and PSP.

It is often difficult to differentiate clinically between Parkinson's disease (PD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP).The objective of this work was to investigate whether combined pre‐ and postsynaptic dopaminergic single photon emission computed tomography (SPECT) scanning can reliably demonstrate changes in the nigrostriatal dopaminergic system and help differentiate between normal controls, PD, MSA, and PSP patients. We performed SPECT evaluation of the dopamine transporter (DAT) and dopamine D2 receptors (D2). SPECT scans using [¹²³I]β‐CIT (for DAT) and [¹²³I]IBF (for D2) were performed in 18 patients with PD (12 dopa‐naïve and 6 on levodopa and/or dopamine agonists), 7 with MSA of the striatonigral degeneration type, 6 with PSP, and 29 normal controls. Antiparkinsonian drugs were withheld for at least 12 hours before the scans. DAT and D2 binding potentials (Rv = V₃/V₂) were measured for caudate, anterior, and posterior putamen on the sides ipsilateral and contralateral to the worst motor symptoms. DAT binding in the posterior putamen was markedly reduced in all patients. However, D2 binding in posterior putamen was significantly increased in dopa‐untreated PD, being greater than the normal range in 4 of 12 (33%), and it was significantly reduced in MSA, being below the normal range in 5 of 7 (71%). None of the patients with PD showed reduced D2 binding below the normal range in posterior putamen. The degree of DAT binding could not discriminate between the patient groups. The ratio of posterior putamen to caudate percentage D2 Rv compared with the controls showed an opposite pattern between PD or PSP and MSA; the caudate was greater in 16 of 18 with PD and 6 of 6 with PSP, whereas caudate was less in 5 of 7 with MSA. These findings suggest that DAT SPECT may be useful in differentiating parkinsonism from controls and D2 SPECT in further differentiating MSA from Parkinson's disease and possibly PSP. © 2002 Movement Disorder Society.     

Clinical and [<Superscript>123</Superscript>I]FP-CIT SPET imaging follow-up in patients with drug-induced parkinsonism

We recently found that patients with drug-induced parkinsonism (DIP) may have normal (group I) or abnormal (group II) putamen [¹²³I]FP-CIT DAT (dopamine transporter) binding. In this study we reassessed clinical features and DAT binding in 19 of the original 32 patients (10 of group I and 9 of group II) after a 19–39-month follow-up period and tested the effects of chronic levodopa treatment in both cohorts of patients. In group I patients, [¹²³I]FP-CIT SPET (single photon emission tomography) was still normal in all patients at follow-up; DAT binding and UPDRS (Unified Parkinson’s Disease Rating Scale) motor score values did not differ from baseline. In group II patients, [¹²³I]FP-CIT SPET was still abnormal at follow-up; putamen DAT binding was significantly reduced and UPDRS III score higher compared to baseline. Levodopa treatment improved motor symptoms in three out of ten patients of group I and in eight out of nine patients of group II. No adverse psychiatric effects were observed in any of the patients. This study shows that DAT binding imaging may help to identify subjects with DIP secondary to a loss of dopamine nerve terminals in the context of a progressive degenerative parkinsonism. Patients with DIP may benefit from levodopa therapy, particularly when dopamine nerve terminal defects are present, and this should be considered in the therapeutic management of these patients.     

ECT in Parkinson's disease – dopamine transporter visualised by [123I]-β-CIT SPECT

Summary. Parkinson's disease (PD) is characterised by a loss of dopaminergic neurones in the basal ganglia. These neurones may be visualised by single photon emission computed tomography (SPECT) with the cocaine analogue 2β-carboxymethyl-3-β-(4-iodophenyl)tropane ([¹²³I]β-CIT), which labels the dopamine reuptake sites in the nerve terminals. In order to evaluate the possibility to predict the outcome of ECT a prospective study was per-formed with six PD patients in whom the [¹²³I]β-CIT uptake was measured before and after an electroconvulsive therapy (ECT) series. The side-to-side difference in the radiotracer uptake was found to be significantly lower in striatum located contralaterally to the part of the body with the most pronounced symptomathology. No significant change in uptake of the radioligand was seen after ECT. Patients with best uptake and thus with less advanced PD improved most after ECT. The possibility to use the [¹²³I]β-CIT uptake to predict the outcome of ECT treatment has to be further evaluated. Received February 23, 1999; accepted January 4, 2000     

The role of <Superscript>123</Superscript>I-FP-CIT-SPECT in the differential diagnosis of Parkinson and tremor syndromes: a critical assessment of 125 cases

¹²³I-FP-CIT-SPECT is useful in the differential diagnosis of Parkinson’s disease (PD) and tremor syndromes. Recently, there have been reports on normal nigrostriatal uptake of radio ligands in PD patients, referred to as scans without evidence of dopaminergic deficit (SWEDDs). Furthermore, a dopaminergic deficit has been described in some cases of different tremor types. We sought to clarify the occurrence of SWEDDs in PD and a possible association of various tremor types with PD. We performed a retrospective case analysis of 125 patients with diagnostically uncertain Parkinsonian or non-Parkinsonian tremor syndromes with clinical assessments and ¹²³I-FP-CIT-SPECT. A total of 36/40 (90%) patients with the predominant clinical feature of a postural and/or kinetic tremor showed normal DAT SPECT; 73/85 (86%) with predominant clinical symptoms of PD showed abnormal DAT SPECT with lower overall radio ligand uptake and a significant asymmetry contralateral to the clinically more affected side. In all, 4/40 (10%) of non-Parkinsonian tremor patients had abnormal DAT SPECT, but no corresponding asymmetry of radio ligand uptake. Probable essential tremor was considered clinically in follow-up assessments although final diagnosis of these four tremor cases remains inconclusive. A total of 12/85 (14%) clinically suspected PD patients had normal DAT SPECT (SWEDDs). Clinical reassessment identified two patients with dystonic tremor. Five patients with a positive response to levodopa remained unclear. In four cases of suspected PD with normal DAT SPECT, non-neurologic diseases were identified. One case showed a complete and spontaneous remission of symptoms. DAT SPECT offers an objective method to confirm or exclude a dopaminergic deficit in tremor predominant parkinsonism for clinically inconclusive cases. There was no evidence of a decrease in DAT binding in the majority of patients with postural and/or kinetic tremor. The striatal asymmetry index is a further helpful tool for differentiating PD from non-PD tremor syndromes.     

Severity of neuropsychiatric symptoms and dopamine transporter levels in dementia with Lewy bodies: A 123I‐FP‐CIT SPECT study

Neuropsychiatric symptoms are frequent in dementia with Lewy bodies (DLB). Dopamine transporter (DAT) imaging with ¹²³I‐labeled ligand N‐δ‐(fluoropropyl)‐2β‐carbomethoxy‐3β‐(4‐iodophenyl)tropene (¹²³I‐FP‐CIT), which reliably measures midbrain dopaminergic dysfunction, has provided important evidence on the neurobiological substrate of some of these symptoms including apathy and depression. However, little is known on DAT levels and other distressing symptoms such as delusions and hallucinations. Therefore, ¹²³I‐FP‐CIT imaging was performed in 18 well‐characterized patients with DLB, and striatal DAT levels were correlated with the frequency/severity ratings of several neuropsychiatric symptoms. A wide range of neuropsychiatric symptoms could be observed in the sample. Significant correlations were observed between decreased striatal DAT levels and visual hallucinations. Although there were no correlations between striatal DAT levels and other neuropsychiatric symptoms, when considering the putamen and the caudate nucleus separately, delusions, depression, and apathy were inversely correlated to decreased caudate DAT levels. Theseresults provide intriguing evidence on the involvement of the mesocortical dopaminergic pathways in neuropsychiatric symptoms in DLB. © 2009 Movement Disorder Society     

血管性帕金森综合征多巴反应异质性的队列研究

目的 研究基于病变部位的血管性帕金森综合征（vascular parkinsonism,VP）亚型队列的多巴反应性差异。 方法 对41例VP和45例帕金森病（Parkinson’s disease,PD）患者在基线和2年期随访时进行急性左旋多巴试验评测患者的多巴反应性。将VP组按照磁共振（magnetic resonance imaging,MRI）显示的病变部位分型。对VP各亚型和PD组在基线、2年期随访的多巴反应性进行了比较。应用一致性检验评价基线急性左旋多巴试验对2年期随访时多巴反应性的预测价值。 结果 在基线以及2年期随访时,VP组中基底节病变亚组的多巴反应性程度和急性左旋多巴试验阳性率均高于白质病变亚组,但低于PD组（P<0.05）。2年期随访时VP总体以及基底节病变亚组的多巴反应性低于基线（P<0.05）;白质病变亚组的多巴反应性与基线的差异无统计学意义（P>0.05）。VP组基线急性左旋多巴试验结果与2年期随访时急性左旋多巴试验结果的一致性有统计学意义,kappa值为0.438（P<0.05）;其中白质病变组的阳性预测率和阴性预测率分别为0和100%;基底节病变组的阳性预测率和阴性预测率分别为14.3%和100%。 结论 VP的基底节病变亚组和白质病变亚组的急性多巴反应性随病程进展有不同的变化特征。     

Differential neuropsychological profiles in Parkinsonian patients with or without vascular lesions

The purpose of this study is to compare the neuropsychological profile of patients affected by parkinsonism and vascular lesions to that in patients with PD alone (PD) and to evaluate whether the brain vascular lesion load is associated with neuropsychological variables. Thirty‐six nondemented patients with parkinsonism were divided into 3 groups of 12 patients each, according to both clinical history and the presence of brain vascular lesions and/or dopaminergic denervation as revealed by magnetic resonance and dopamine transporter imaging, respectively. The first group had vascular lesions without dopaminergic denervation (VP group); the second group had vascular lesions and dopaminergic denervation (DD) (VP+DD group); and the third group consisted of patients with dopaminergic denervation (PD group) without vascular lesions. All patients underwent neurological and neuropsychological assessments. The groups differed in disease duration, age at onset, and cerebrovascular risk factors. The VP and VP+DD groups performed worse than the PD group on frontal/executive tasks. Regardless of the presence of dopaminergic denervation, cerebrovascular lesions in hemispheric white matter, basal ganglia, and cerebellum have an important effect in determining early onset and severity of cognitive impairment in patients with parkinsonism. © 2009 Movement Disorder Society     

Decreased single-photon emission computed tomographic {123I}β-CIT striatal uptake correlates with symptom severity in parkinson's disease

Previous studies have utilized single-photon emission computed tomography (SPECT) to demonstrate decreased {¹²³I}β-CIT striatal uptake in idiopathic Parkinson disease (PD) patients. The present study extendss this work by examining SPECT outcome measures in a larger group of PD patients with varying disease severity. Twenty-eight l-dopa-responsive PD patients (Hoehn-Yahr stages 1–4) and 27 healthy controls had SPECT scans at 18 to 24 hours after injection of {¹²³I}β-CIT. Specific to nondisplaceable striatal uptake ratios (designated V_3″) were correlated with Hoehn-Yahr stage and Unified Parkinson's Disease Rating Scale (UPDRS) subscores. Linear discriminant function analyses utilizing striatal uptakes, putamen-to-caudate ratios, and ipsilateral-contralateral asymmetry indices were performed. Decreased striatal tracer uptake (V_3″) was correlated with total UPDRS score for both contralateral and ipsilateral striatum. Putamen uptake was relatively more reduced than caudate with mean putamen:caudate ratios of 0.50 ± 0.17 and 0.82 ± 0.09 for PD patients and controls, respectively. Ipsilateral:contralateral asymmetry was significantly greater in PD patients than controls. Discriminant function analysis utilizing V_3″ for ipsilateral and contralateral caudate and putamen correctly classified all 55 cases. These data demonstrate Marchked differences in {¹²³I}β-CIT SPECT measures in healthy controls and PD patients. The significant correlation of SPECT measures with motor severity suggests {¹²³I}β-CIT may be a useful Marchker of disease severity in PD.