Olfactory function in atypical parkinsonian syndromes

Introduction – Olfaction is markedly impaired in patients with idiopathic Parkinson's disease (IPD). This deficit contrasts with reports of preserved or only mildly reduced olfaction in patients with atypical parkinsonism. However, the sensitivity and specificity of olfactory function testing in the differential diagnosis of parkinsonian syndromes has not been studied. In addition, olfactory function in patients with corticobasal degeneration (CBD) is unknown. Material and methods — Using the University of Pennsylvania Smell Identification Test (UPSIT) with a test score ranging from 0 to 40 we studied olfactory function in patients with IPD as well as other parkinsonian syndromes including CBD and progressive supranuclear palsy (PSP). Results — UPSIT scores in 118 patients with IPD, 29 with MSA, 15 with PSP, and 7 patients with CBD, as well as in 123 healthy control subjects revealed a marked impairment in the IPD group in contrast to mild impairment in MSA patients and normal olfaction in PSP and CBD patients. An UPSIT score of 25/40 was associated with a sensitivity of 77% and a specificity of 85% in differentiating IPD from atypical parkinsonism. Conclusions — These results indicate that olfactory function is differentially impaired or preserved in distinct parkinsonian syndromes and that it might also have some value as a diagnostic pointer. Thus, preserved or mildly impaired olfactory function in a parkinsonian patient is more likely to be related to atypical parkinsonism such as MSA, PSP or CBD, whereas markedly reduced olfaction is more suggestive of IPD.     

Visuospatial functions in atypical parkinsonian syndromes

OBJECTIVES: Visuospatial deficits have been occasionally reported but never systematically studied in atypical parkinsonian syndromes. The interpretation of existing studies is complicated by the possible influence of motor and frontal executive deficits. Moreover, no attempt has been made to distinguish visuoperceptual from visuospatial tasks. The aim of the present study was to assess visuoperceptual and visuospatial abilities in three atypical parkinsonian syndromes while minimising the influence of confounding variables. METHODS: Twenty patients with multiple system atrophy (MSA), 43 with progressive supranuclear palsy (PSP), and 25 with corticobasal degeneration (CBD) as well as 30 healthy age matched controls were examined with the Visual Object and Space Perception Battery (VOSP). RESULTS: Visuospatial functions were intact in MSA patients. PSP patients showed mild deficits related to general cognitive decline and the severity of oculomotor symptoms. The CBD group showed the most pronounced deficits, with spatial tasks more impaired than object based tasks. Performance on object based, but not spatial, tasks was related to general cognitive status. The extent of the visuospatial impairment could not be predicted from disease duration or severity. CONCLUSION: Visuospatial functions are not consistently impaired in atypical parkinsonian syndromes. The degree and pattern of impairment varies across the diseases, suggesting that the observed deficits could have a different neural basis in each condition. The distinction between the object based ("ventral stream") and the space oriented ("dorsal stream") processing might be useful in the interpretation of visuospatial deficits in parkinsonian syndromes, especially in CBD.     

Systematic review of proton magnetic resonance spectroscopy of the striatum in parkinsonian syndromes

It has been suggested that proton magnetic resonance spectroscopy (MRS) of the striatum can differentiate between parkinsonian syndromes. The present study aims to examine this claim by performing a systematic review of the existing literature. A MEDLINE search was performed between 1966 and October 1999, along with searches of conference abstracts and reference lists of papers identified. Eleven groups have used MRS to examine metabolite ratios in the striatum in Parkinsonian syndromes. A number of these have shown reduced N-acetylaspartate/choline (NAA/Cho) and/or N-acetylaspartate/creatine (NAA/Cr) ratios in either idiopathic Parkinson's disease (IPD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP) or corticobasal degeneration. However, the heterogeneity in the results precludes the use of any of these findings in differential diagnosis at the present time. The only group to use absolute metabolite concentrations rather than ratios showed that the decreased NAA/Cho ratio in IPD was because of an increase in choline which is of uncertain biological significance. Further large multicentre trials are required using absolute quantitation of tissue metabolite concentrations and a standardized technique. The patients entering such studies must be rigorously assessed to establish the diagnosis of the type of parkinsonism as accurately as possible. Any discriminatory abnormality must be tested in a large prospective study of newly presenting parkinsonian patients with long-term clinical follow up and ultimate pathological confirmation of the diagnosis as far as possible.     

Anal sphincter EMG in the diagnosis of parkinsonian syndromes

Winge K, Jennum P, Lokkegaard A, Werdelin L. Anal sphincter EMG in the diagnosis of parkinsonian syndromes.
Acta Neurol Scand: 2010: 121: 198–203.
© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Background – The role of electromyography (EMG) recorded from the external anal sphincter (EAS) in the diagnosis of atypical parkinsonian syndromes is a matter for continuous debate. Most studies addressing this issue are retrospective. Methods – In this study, we prospectively investigated six patients with Parkinson’s Disease (IPD), 14 patients with multiple system atrophy (MSA) and eight with progressive supranuclear palsy (PSP) using EMG of the EAS, motor‐evoked potential (MEP) to the EAS and EMG of m. gastrocnemius and nerve conduction velocity measured at the sural nerve. Patients were followed up for 2 years to secure correct diagnosis. Results – The mean duration of motor unit potentials (MUPs) recorded from the EAS was significantly longer in patients with MSA and PSP compared with MUPs recorded from patients with PD (P < 0.005 for both). There were no signs of diffuse loss of motor neurons or peripheral neuropathy. MEP revealed signs of supranuclear affection in patients with MSA, whereas in patients with PSP the mechanism is a focal loss of motor neurons in Onuf’s nucleus. Conclusion – Abnormal EMG of the EAS is strongly suggestive of atypical parkinsonism and the pathophysiology may be different in patients with MSA and PSP.     

Atypical parkinsonian syndromes: a general neurologist's perspective

The differential diagnosis of atypical parkinsonian syndromes is challenging. These severe and often rapidly progressive neurodegenerative disorders are clinically heterogeneous and show significant phenotypic overlap. Here, clinical, imaging, neuropathological and genetic features of multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration and frontotemporal lobar degeneration (FTLD) are reviewed. The terms corticobasal degeneration and FTLD refer to pathologically confirmed cases of corticobasal syndrome and frontotemporal dementia (FTD). Frontotemporal lobar degeneration clinically presents as the behavioral variant FTD, semantic variant primary progressive aphasia (PPA), non‐fluent agrammatic variant PPA, logopenic variant PPA and FTD associated with motor neuron disease. While progressive supranuclear palsy and corticobasal syndrome have been called Parkinson‐plus syndromes in the past, they are now classified as FTD‐related disorders, reflecting that they pathologically differ from α‐synucleinopathies like multiple system atrophy and Parkinson disease. The contribution of genetic factors to atypical parkinsonian syndromes is increasingly recognized. Genes involved in the etiology of FTLD include MAPT, GRN and C9orf72. Novel neuroimaging techniques, including tau positron emission tomography imaging, are being investigated. Multimodal magnetic resonance imaging approaches and automated magnetic resonance imaging volume segmentation techniques are being evaluated for optimized differential diagnosis. Current treatment options are symptomatic, and disease modifying therapies are under active investigation.     

The final diagnoses of patients with clinically suspected atypical parkinsonian syndromes

We report on 189 patients who were evaluated for APS. Final diagnoses included 77 cases of PSP, 32 patients with MSA and 11 patients with CBS. 35 patients were diagnosed or confirmed with iPD, while in 26 cases a differentiation between iPD and APS could not be definitely made.     

Abnormal metabolic networks in atypical parkinsonism

Spatial covariance analysis has been used with ¹⁸F‐fluorodeoxyglucose (FDG) PET to detect and quantify specific metabolic patterns associated with Parkinson's disease (PD). However, PD‐related patterns cannot necessarily serve as biomarkers of the processes that underlie the atypical parkinsonian syndromes. In this FDG PET study, we used strictly defined statistical criteria to identify disease‐related metabolic patterns in the imaging data from patients with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP), the two most common of these atypical conditions. We found that MSA and PSP were each associated with a specific, highly stable metabolic brain network (P < 0.0001, bootstrap estimation). The MSA‐related pattern was characterized by decreased metabolism in the putamen and cerebellum. The PSP‐related pattern was characterized by metabolic decreases in the brainstem and medial frontal cortex. For both conditions, pattern expression was significantly elevated in patients relative to age‐matched healthy control subjects (P < 0.001). For each condition, we validated the associated disease‐related metabolic pattern by computing its expression on an individual scan basis in two independent patient cohorts, and in one subsequent healthy volunteer cohort. We found that for both MSA and PSP, prospective assessments of pattern expression accurately discriminated patients from controls (P < 0.001). These findings suggest that the major atypical parkinsonian syndromes are associated with distinct patterns of abnormal regional metabolic activity. These disease‐related networks can potentially be used in conjunction with functional brain imaging as quantifiable biomarkers for the assessment of these pathological conditions. © 2008 Movement Disorder Society     

进行性核上性麻痹与多系统萎缩的头部MRI和FDG-PET比较

目的对比研究进行性核上性麻痹(PSP)与多系统萎缩(MSA)的脑干MRI表现和头部葡萄糖代谢特征。方法对11例PSP患者、37例MSA患者和43例健康对照进行头部MRI平扫检查,并计算MRI正中矢状面T1加权像上中脑截面面积,其中5例PSP和19例MSA进行了18F-FDG PET检查。结果(1)MRI:11例PSP正中矢状位T1加权像均可见中脑上缘平坦或凹陷表现,呈"蜂鸟征",而MSA患者和健康对照组未见上述表现。37例MSA患者中有34例轴位T2加权像桥脑可见"十字征"样长T2异常信号。PSP患者正中矢状位T1加权像上中脑截面面积分别低于MSA组和健康对照组(P<0.01)。(2)PET:PSP组主要表现为对称性额叶低代谢;MSA组主要表现为额、顶、颞叶普遍低代谢,纹状体对称性代谢降低,丘脑代谢高于纹状体。结论PSP中脑MRI特征和头部葡萄糖代谢特征与MSA和健康对照有明确差异,有助于PSP与MSA的鉴别诊断。     

Freezing of gait in postmortem-confirmed atypical parkinsonism.

The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies.     

Milestones in atypical and secondary Parkinsonisms

During the last decades, atypical parkinsonian disorders such as multiple system atrophy, dementia with Lewy bodies, progressive supranuclear palsy, and corticobasal degeneration along with secondary parkinsonian disorders have been increasingly recognized as important causes of parkinsonism. Although treatment options are largely limited to date, remarkable progress has occurred through advances in the fields of molecular biology and diagnostic neuroimaging, resulting in intense preclinical drug discovery programs. Early‐investigation‐assisted clinical diagnosis has become more crucial than ever because disease‐modifying therapies will hopefully become available within this decade. © 2011 Movement Disorder Society     

Lack of autonomic nervous dysfunction in progressive supranuclear palsy, a study of blood pressure variability

Blood pressure and heart rate variability were analyzed in eight patients with progressive supranuclear palsy in comparison with two control groups (10 healthy patients and 10 patients with multiple system atrophy). Blood pressure and heart rate were recorded using digital photoplethysmography with the patient in supine position and during a head-up-tilt test (70° for 10 minutes). Spectral analysis was performed using fast Fourier transformation for 512 consecutive systolic blood pressure and heart rate values. The head-up-tilt test induced a significant increase in systolic blood pressure in patients with progressive supranuclear palsy and in healthy patients and a significant systolic blood pressure decrease in patients with multiple system atrophy. During the head-up-tilt test, low-frequency energy of systolic blood pressure (70–130 mHz) that reflected baroreflex-dependent sympathetic tone also increased in patients with progressive supranuclear palsy and in healthy patients. By contrast, in patients with multiple system atrophy, the low-frequency energy of systolic blood pressure decreased significantly. The changes observed in the low-frequency band and the high-frequency band of heart rate (reflecting parasym-pathetic drive to the heart) were not different among the three groups. These data show the lack of impairment in autonomic nervous system activity in patients with progressive supranuclear palsy.     

Applause sign in parkinsonian disorders and Huntington's disease

The applause sign has been previously reported to be indicative of neurodegenerative disorders, such as progressive supranuclear palsy (PSP). In order to determine the sensitivity, specificity, and positive predictive value, we tested it in patients with PSP, Parkinson's disease (PD), multiple system atrophy (MSA), corticobasal degeneration (CBD), and Huntington's disease (HD). Subjects were asked to clap three times after demonstration by the examiner. The performance was scored as follows: 3 = claps only three times; 2 = claps four times; 1 = claps 5 to 10 times; 0 = claps >10 times. The clap test was videotaped and rated. Patients with CBD, MSA, and PSP showed significant differences in clap scores compared with normal controls. The test differentiated patients with CBD from those with PD (P < 0.005) and HD (P < 0.005), but failed to discriminate patients with PSP from other parkinsonian groups. The specificity of the applause sign is 100% in distinguishing parkinsonian patients from normal subjects with the highest sensitivity in CBD patients. We concluded that the applause sign is highly specific for parkinsonian disorders but it is not a specific sign for PSP; it appears to be most sensitive for CBD. © 2008 Movement Disorder Society     

A comparison of depression,anxiety, and health status in patients with progressive supranuclear palsy and multiple system atrophy

The objective of this study was to compare subjective health status and its correlates in progressive supranuclear palsy (PSP) and multiple system atrophy (MSA). One hundred eighty‐eight patients with PSP and 286 patients with MSA completed EQ‐5D and Hospital Depression and Anxiety Scale. The impact on mobility, usual activities, and self‐care was similarly high in both groups after similar duration. Fifty‐six percent of PSP and 43% of MSA had probable depression, and 37% of both groups had probable anxiety. Patients with PSP had significantly higher depression scores, but groups did not differ in anxiety scores. Patients with MSA had significantly greater pain/discomfort than patients with PSP. The most important association with subjective health status was with depressive symptoms, which accounted for 38% and 29% of EQ‐5D variance in patients with PSP and MSA, followed by disease severity and anxiety scores. We conclude that depressive symptoms were common in both disorders, but more severe in PSP. Anxiety symptoms affected 37% of patients in both groups and contributed to impaired subjective health status. Pain was more problematic in MSA than PSP. © 2010 Movement Disorder Society     

Proton magnetic resonance spectroscopy in parkinson's disease and atypical parkinsonian disorders

Proton magnetic resonance spectroscopy (¹H-MRS), localized to the lentiform nucleus, was carried out in 12 patients with idiopathic Parkinson's disease (IPD), seven patients with multiple-system atrophy (MSA), seven patients with progressive supranuclear palsy (PSP), and 10 healthy age matched controls. The study assessed the level of N-acetylaspartate (NAA), creatine–phosphocreatine (Cr), and choline (Cho) in the putamen and globus pallidus of these patients. NAA/Cho and NAA/Cr ratios were significantly reduced in MSA and PSP patients. No significant difference was found between IPD patients and controls. These results suggest an NAA deficit, due to neuronal loss, in the lentiform nucleus of MSA and PSP patients. ¹H-MRS is a noninvasive technique that can provide useful information regarding striatal neuronal loss in basal ganglia of patients with atypical parkinsonian disorders and represents a potential tool for diagnosing these disorders.     

Botulinum toxin treatment in atypical parkinsonian disorders associated with disabling focal dystonia

We investigated the efficacy of botulinum toxin A (BtxA) therapy in patients with atypical parkinsonian disorders (APD) exhibiting different types of disabling focal dystonia unresponsive to oral drug therapy. Eight patients with functionally disabling focal dystonia out of a series of 60 consecutive patients with APDs regularly treated at our outpatient movement disorders clinic were included. Patients were diagnosed according to established criteria and had disabling limb dystonia (n=4) or craniocervical dystonia (n=4) unresponsive to oral pharmacological treatment. Localization and dose of BtxA injections was determined individually based on clinical examination as well as EMG in patients with limb dystonia. BtxA reduced dystonic symptoms in all patients; only one developed a transient local side-effect. BtxA was particularly effective in the long-term treatment (up to 50 months) of blepharospasm associated with progressive supranuclear palsy (PSP). BtxA also alleviated PSP-associated retrocollis and orofacial dystonia with lower lip retraction associated with PSP and multiple system atrophy. BtxA treatment of limb dystonia in corticobasal degeneration (CBD) temporarily improved hand and arm function in early disease stages while treatment in advanced stages reduced pain, facilitated hygiene and prevented secondary contractures. Limb dystonia was also alleviated by BtxA therapy in one patient with neuronal multisystem degeneration of undetermined cause. The results suggest that BtxA therapy may represent an effective means of alleviating disabling focal dystonia in different APDs. Particularly in early stage APD with disabling limb dystonia local BtxA injections may result in functional improvement. Received: 14 March 2001, Accepted: 25 July 2001     

Incidence of Parkinson's disease and atypical parkinsonism: Russian population‐based study

Data on the incidence of Parkinson's disease (PD) and atypical parkinsonian syndromes (APS) in East European countries and Asia are limited. The objective of this prospective population‐based study was to determine the incidence of PD and APS in the Russian population. The study area was a large district of Moscow with a population of 1,237,900 inhabitants. Multiple sources of case ascertainment were used to identify incident cases of PD and APS between July 2006 and December 2008. All incident cases were examined by a specialist and followed up prospectively to confirm the diagnosis. The age‐standardized incidence rates per 100,000/year were 9.03 [95% confidence interval (CI) 8.01–10.15] for PD, 0.11 (95% CI 0.03–0.23) for multiple system atrophy, 0.14 (95% CI 0.08–0.21) for progressive supranuclear palsy, and 0.02 (95% CI 0.01–0.12) for corticobasal degeneration. The age‐standardized male‐to‐female ratio of PD was 0.87 for all ages and 1.46 for those aged 60 and older. A high proportion of new cases with PD (34%) and APS (50%) had comorbid depressive symptoms. Given the rapid growth of the elderly population in Eastern Europe and Asia, the epidemiology of PD and APS in these regions should be investigated in greater depth. The incidence of PD in our study was slightly lower than in studies of Western populations and the male‐to‐female ratio was closer to those reported in studies from Asia. The clinical implication of our study is that it highlights the need for better diagnosis and treatment of depression in early stages of PD. © 2010 Movement Disorder Society