Vascular pseudoparkinsonism

Practical Overview of 123I-Ioflupane Imaging in Parkinsonian Syndromes

Parkinsonian syndromes are a heterogeneous group of progressive neurodegenerative disorders involving the nigrostriatal dopaminergic pathway and are characterized by a wide spectrum of motor and nonmotor symptoms. These syndromes are quite common and can profoundly impact the lives of patients and their families. In addition to classic Parkinson disease, parkinsonian syndromes include multiple additional disorders known collectively as Parkinson-plus syndromes or atypical parkinsonism. These are characterized by the classic parkinsonian motor symptoms with additional distinguishing clinical features. Dopamine transporter SPECT has been developed as a diagnostic tool to assess the levels of dopamine transporters in the striatum. This imaging assessment, which uses iodine 123 (123I) ioflupane, can be useful to differentiate parkinsonian syndromes caused by nigrostriatal degeneration from other clinical mimics such as essential tremor or psychogenic tremor. Dopamine transporter imaging plays a crucial role in diagnosing parkinsonian syndromes, particularly in patients who do not clearly fulfill the clinical criteria for diagnosis. Diagnostic clarification can allow early treatment in appropriate patients and avoid misdiagnosis. At present, only the qualitative interpretation of dopamine transporter SPECT is approved by the U.S. Food and Drug Administration, but quantitative interpretation is often used to supplement qualitative interpretation. The authors provide an overview of patient preparation, common imaging findings, and potential pitfalls that radiologists and nuclear medicine physicians should know when performing and interpreting dopamine transporter examinations. Alternatives to 123I-ioflupane imaging for the evaluation of nigrostriatal degeneration are also briefly discussed. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Intenzo and Colarossi in this issue.

The etiopathogenetic and pathophysiological spectrum of parkinsonism

Parkinsonism is a syndrome characterized by bradykinesia, rigidity, and tremor. Parkinsonism is a common manifestation of Parkinson's disease and other neurodegenerative diseases referred to as atypical parkinsonism. However, a growing body of clinical and scientific evidence indicates that parkinsonism may be part of the phenomenological spectrum of various neurological conditions to a greater degree than expected by chance. These include neurodegenerative conditions not traditionally classified as movement disorders, e.g., dementia and motor neuron diseases. In addition, parkinsonism may characterize a wide range of central nervous system diseases, e.g., autoimmune diseases, infectious diseases, cerebrospinal fluid disorders (e.g., normal pressure hydrocephalus), cerebrovascular diseases, and other conditions. Several pathophysiological mechanisms have been identified in Parkinson's disease and atypical parkinsonism. Conversely, it is not entirely clear to what extent the same mechanisms and key brain areas are also involved in parkinsonism due to a broader etiopathogenetic spectrum. We aimed to provide a comprehensive and up-to-date overview of the various etiopathogenetic and pathophysiological mechanisms of parkinsonism in a wide spectrum of neurological conditions, with a particular focus on the role of the basal ganglia involvement. The paper also highlights potential implications in the diagnostic approach and therapeutic management of patients. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.

Poststroke Parkinsonism associates with an increased mortality risk in patients

Background

To determine whether poststroke Parkinsonism (PSP) increases mortality risk in poststroke patients by using Taiwan National Health Insurance Research Database (NHIRD).

Methods

We analyzed NHIRD data of ≥40-year-old patients diagnosed as having stroke [International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) codes 430-438] between 2000 and 2013. Poststroke patients were divided into those with subsequent PSP (ICD-9-CM codes 332, 332.0, and 332.1) and without PSP (non-Parkinsonism, PSN) cohorts, all compared with a sex-, age-, comorbidity-, and index date-matched comparison cohort. We calculated adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of all-cause mortality risk in these cohorts after adjustments for age, sex, and comorbidities.

Results

PSP was noted in 11.87% (1,644/13,846) of poststroke patients. In the PSN, PSP, and comparison cohorts, mortality incidence rates were 69.1, 124.9, and 38.8 per 1,000 person-years, respectively. Compared with the comparison cohort, the mortality risks in patients aged 40 to 64, 65 to 74, and ≥75 years were respectively 2.21-, 1.91-, and 1.86-fold higher mortality risks in the PSN cohort and 4.57-, 2.84-, and 2.27-fold higher mortality risks in the PSP cohort. Male sex further increased mortality risk in poststroke patients with PSP.

Conclusions

Long-term all-cause mortality risk is increased by 1.39 times in poststroke patients with PSP than in those without. Our findings depict vital information in incidence and risk of PSP. Those would aid clinicians and the government to improve future poststroke care.

Clinical features and neuropsychological profile in vascular parkinsonism

BACKGROUND

The clinical profile in vascular parkinsonism (VP) patients is well described in the literature, but little is known about the neuropsychological features of this disease. The aim of our study was to evaluate the clinical characteristics and the profile of cognitive impairment in patients with VP.

METHODS

We prospectively evaluated 12 patients with VP, 15 with Parkinson's disease (PD) and 13 healthy controls (HC) with similar age and sex distribution. Different clinical and demographic details were collected. All subjects underwent detailed neurological and neuropsychological examinations. The neuropsychological tests included analysis of global efficiency, executive function, verbal memory, language and visuospatial function.

RESULTS

VP patients exhibited lower disease duration, older age at onset and higher frequency of cardiovascular risk factors. Non-motor symptoms were found to be more frequent in PD. We found that VP patients developed cognitive impairment with a significantly higher frequency than HC of a similar age. Additionally, we found that these patients had a global pattern of cognitive impairment, including executive function, verbal memory and language. Only visuospatial function was more impaired in PD than in HC.

CONCLUSIONS

Our data contribute to clarify the pattern of neuropsychological impairment in VP. Therefore, in the clinical evaluation, besides assessing the motor status of the patient, given that these symptoms are frequently found not to be self-reported complaints, the neurologist should evaluate them routinely as a comprehensive assessment of this disease.

Impact of subcortical white matter lesions on dopamine transporter SPECT

Subcortical arteriosclerotic encephalopathy (SAE) can affect the nigrostriatal system and presumably cause vascular parkinsonism (VP). However, in patients with SAE, the differentiation of VP from idiopathic Parkinson's disease (IPS) is challenging. The aim of the present study was to examine the striatal dopamine transporter (DAT) density in patients with parkinsonism and SAE. Fifteen consecutive patients with parkinsonian symptoms displayed SAE, as detected by magnetic resonance imaging (MRI). Fifteen retrospectively chosen, matched patients with diagnosis of IPS without any abnormalities in MRI served as a reference group. DAT SPECT was performed using the tracer ¹²³I-FP-CIT. Scans were acquired on a triple-head SPECT system (Multispect 3, Siemens) and analysed using the investigator-independent BRASS™ software (HERMES). In the SAE group, a DAT deficit was observed in 9/15 patients. In contrast, all patients from the IPS group showed a reduced DAT binding (p = 0.008). The specific binding ratios (BR) of putamen contralateral to the side of the more affected limb versus occipital lobe were in trend higher in patients with SAE versus patients in the IPS-group (p = 0.053). Indices for putaminal asymmetry (p = 0.036) and asymmetry caudate-to-putamen (p = 0.026) as well as the ratio caudate-to-putamen (p = 0.048) were significantly higher in IPS patients having no SAE. DAT deficit was less pronounced in patients with SAE and parkinsonism than in patients with IPS without any abnormalities in the MRI. A potential role of DAT SPECT in the differential diagnosis of VP and IPS requires more assessments within prospective studies.

Cerebral white matter lesions and lacunar infarcts contribute to the presence of mild parkinsonian signs

BACKGROUND AND PURPOSE

Mild parkinsonian signs (MPS) are common in elderly people and may be an early stage of parkinson(ism). They might be related to cerebral small-vessel disease, although this association remains incompletely understood. To identify subjects at early stages of the disease, we investigated whether the presence of MPS was dependent on the severity and location of small-vessel disease, including white matter lesions and lacunar infarcts.

METHODS

Four hundred thirty individuals, with small-vessel disease, aged between 50 and 85 years, without dementia or parkinsonism, were included in this analysis and underwent MRI scanning. The number and location of lacunar infarcts were rated. White matter lesion volume was assessed by manual segmentation with automated delineating of different regions. Presence of MPS was based on the motor section of the Unified Parkinson's Disease Rating Scale. Associations were determined using logistic regression analysis adjusted for age, sex, and total brain volume.

RESULTS

Severe white matter lesions and the presence of lacunar infarcts were independently associated with the presence of MPS (OR, 2.6; 95% CI, 1.3-4.9 and OR, 1.8; 95% CI, 1.0-3.0). Frontal and parietal white matter lesions and, to a lesser extent, lacunar infarcts in the thalamus were associated with a higher risk of MPS. The presence of lacunar infarcts was independently related to the bradykinesia category of parkinsonian signs.

CONCLUSIONS

This study shows that severe small-vessel disease, especially at certain locations, is associated with MPS signs in older adults. Our findings suggest that small-vessel disease interrupts basal ganglia-thalamocortical circuits involving both the frontal and parietal lobes and hence may result in MPS.

Vascular Parkinsonism and cognitive impairment: literature review, Brazilian studies and case vignettes

Vascular Parkinsonism (VP) is a form of secondary Parkinsonism resulting from cerebrovascular disease. Estimates of the frequency of VP vary greatly worldwide; 3% to 6% of all cases of Parkinsonism are found to have a vascular etiology. In a Brazilian community-based study on Parkinsonism, 15.1% of all cases were classified as VP, the third most common form, with a prevalence of 1.1% in an elderly cohort. Another Brazilian survey found a prevalence of 2.3% of VP in the elderly. VP is usually the result of conventional vascular risk factors, particularly hypertension, leading to strategic infarcts of subcortical gray matter nuclei, diffuse white matter ischaemic lesions and less commonly, large vessel infarcts. Patients with VP tend to be older and present with gait difficulties, symmetrical predominant lower-body involvement, poor levodopa responsiveness, postural instability, falls, cognitive impairment and dementia, corticospinal findings, urinary incontinence and pseudobulbar palsy. This article intends to provide physicians with an insight on the practical issues of VP, a disease potentially confounded with vascular dementia, idiopathic Parkinson's disease, dementia with Lewy bodies and other secondary causes of Parkinsonism.

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.

Higher level gait disorders in subcortical chronic vascular encephalopathy: a single photon emission computed tomography study

BACKGROUND

the so-called higher level gait disorders include several types of gait disorders in which there are no major modifications in strength, tone, sensitivity, coordination and balance. Brain activation sites related to walking have been investigated using SPECT in humans. The aim of the study was to investigate brain activation during walking in subjects with high-level gait disorders due to chronic subcortical vascular encephalopathy.

SUBJECTS

twelve patients with a chronic vascular encephalopathy were enrolled in the study. Seven subjects had apraxic gait while in the other five the gait was normal. All patients had undergone a recent cerebral magnetic resonance that revealed diffused chronic ischemic lesions within the white matter.

METHODS

all 12 patients underwent a regional cerebral blood flow (rCBF) brain SPECT study with (99m)Tc-Bicisate on two separate days and under two different conditions: at rest (baseline) and while walking (functional).

RESULTS

the rCBF increase induced by the treadmill test (functional-baseline), bilaterally in the medial frontal gyrus and in the anterior lobes of the cerebellum, resulted significantly (P < 0.001) lower in patients with gait apraxia versus those without it.

CONCLUSIONS

this study of the brain with SPECT records the areas of perfusion deficit that appear in apraxic subjects when they walk, compared with the recordings obtained with the same investigation performed at rest.

Mild Parkinsonian signs: An overview of an emerging concept

Mild Parkinsonian signs (MPS) include gait and balance changes, rigidity, bradykinesia, and tremor. MPS can occur commonly during the clinical examination of older people who do not have known neurological disease, with prevalence estimates for MPS as a whole ranging from 15% to 95%. MPS are generally progressive and they are coupled with functional difficulties, impaired gait and balance, and increased risks of mild cognitive impairment, dementia, and mortality. The mechanistic basis for these signs is unclear, but is likely to be multifactorial, with possible factors including an age-associated decline in dopaminergic nigrostriatal activity, the early development of neurodegenerative (Lewy body or Alzheimer's type) pathologies in the basal ganglia, or the accumulation of vascular pathology in the brain. It would be valuable to identify those individuals with MPS who are at increased risk for the development of future Alzheimer's disease, full-blown Parkinson's disease, or strokes, and to develop therapeutic strategies to intervene to lessen the likelihood of MPS-related morbidity and mortality.

Subacute hemicorporal parkinsonism in 5 patients with infarcts of the basal ganglia

In 1929, Critchley introduced the term "vascular parkinsonism" (VP), which has been the subject of considerable controversy in neurology. Parkinsonism does not appear to be a frequent consequence of striatal infarcts, although unilateral parkinsonism has been reported as an acute or subacute onset syndrome following strategic infarcts in the striatum. Previous 123-I ioflupane SPECT (DaTSCAN) studies involving radioisotope labeling of the dopamine transporter protein at presynaptic level in patients with IPD (idiopathic Parkinson's disease) have found this technique to be highly sensitive in exploring the nigrostriatal pathway. Previous studies of VP with DatSCAN have been inconclusive. The present study correlates clinical data (unilateral parkinsonism following contralateral lenticular infarction), and radiological (CT/MRI) and functional neuroimaging findings (DatSCAN) in 5 patients with CT/MRI criteria for striatal infarcts. Finally, in 2 of these patients a diagnosis of IPD was made because of the follow-up of clinical signs and pathological DaTSCAN findings not concordant with the size and location of the vascular lesion.

Parkinsonism and tremor disorders. A clinical approach

Differentiation of idiopathic Parkinson's disease from other causes of Parkinsonism, such as Multiple System Atrophy, Progressive Supranuclar Palsy and Vascular Parkinsonism can be difficult. Clinicopathological studies suggest that the clinical diagnosis of idiopathic Parkinson's disease is 76% reliable. Also, clinical differentiation of tremor prominent Parkinsonism from Essential Tremor or Drug induced Parkinsonism may be problematic, especially in the early stages of the disease. Since these disorders are obviously different in clinical progress, it is important for the clinician to address the patient's and family's concerns about prognosis from a firm diagnostic footing. In this article the clinical features of the common and important causes of Parkinsonism and tremor disorders are reviewed and a practical approach is suggested.

[123I] FP-CIT spect study in vascular parkinsonism and Parkinson's disease

There is substantial evidence to support a role for small vessel disease (SVD) as a cause for vascular parkinsonism (VP). Using [(123)I] FP-CIT SPECT (single photon emission computed tomography), we have tried to determine whether VP patients have pre-synaptic dopaminergic function similar to PD patients, and whether the severity of parkinsonian symptoms as well as the levodopa response in VP patients are correlated with pre-synaptic dopaminergic dysfunction. Thirteen patients fulfilling operational clinical criteria for VP had [(123)I] FP-CIT scans. Mean [(123)I] FP-CIT uptake in the basal ganglia was significantly lower in VP patients than in healthy controls, and the asymmetry index was not significantly different between these groups. In contrast, compared with the PD group, only the mean asymmetry index was significantly lower in VP patients. None of the parameters measured was significantly different between VP patients who had an insidious onset of parkinsonism (VPi) and those who had an acute onset (VPa). There was a significant correlation between the bilateral basal ganglia FP-CIT uptake reduction in the VP patients and UPDRS motor scores, but not with the mean % reduction in motor UPDRS after levodopa. We suggest that in the majority of VP patients, pre-synaptic dopaminergic function is reduced. The presence of a rather symmetrical FP-CIT uptake in the basal ganglia may help to distinguish VP from PD and could therefore be used as a criterion for the clinical diagnosis of VP.

[Utility of 123-I ioflupane SPECT in the assessment of patients with Parkinsonian syndrome and cerebral vasculopathy]

OBJECTIVE

To assess the utility of 123-I Ioflupane SPECT (IS) in the identification of the origin of Parkinsonism (vascular or idiopathic) in patients with cerebral vasculopathy (CV) demonstrated by morphological imaging techniques. Also, to assess the therapeutic impact.

MATERIALS AND METHODS

42 patients (16 males and 26 females) with a Parkinsonian syndrome were studied. Average age was 78.7 years (50-88). A dose of 185 MBq of 123 I-Ioflupane was injected in all subjects. SPECT imaging was obtained 5 hours later. All patients had a CT and/or MRI. The final diagnoses, after a minimal follow-up of 12 months, was established by a neurologist expert in movement disorders, based on clinical and imaging features and response to treatment.

RESULTS

14 patients were diagnosed of functional vascular Parkinsonism by alteration of association pathways, 3 of structural vascular Parkinsonism (SVP) with anatomical and functional vascular lesion in striatum, 14 of Parkinson's disease (PD) with CV, 2 of mixed Parkinsonism (PD + SVP) and 9 with others diagnoses different to the previous. The result of IS changed the treatment in 7/42 patients.

CONCLUSION

The IS can have a complementary role to clarify the etiology of Parkinsonism in patients with cerebral vasculopathy. Interpretation of functional and anatomical images within the clinical context of each patient is necessary.

Different clinical and evolutional patterns in late idiopathic and vascular parkinsonism

OBJECTIVE

The aim of this study was to examine the clinical picture of Parkinson's disease (PD) and vascular parkinsonism (VP) in the elderly, in an attempt to differentiate the clinical history, symptoms, signs and response to therapy.

MATERIAL AND METHODS

Thirty-two elderly patients with late onset PD and 45 with VP were enrolled and the clinical features of two groups were compared. All patients underwent brain MRI and were scored using the Unified Parkinson's Disease Rating Scales (UPDRS) -II, -III.

RESULTS

Patients with PD had a younger age at onset and a longer duration of the disease as compared to patients with VP. Nearly all PD patients showed a good response to levodopa therapy, while only 29% of patients with VP were responsive to levodopa treatment. Vascular risk factors as well as postural tremor, gait disorders and pyramidal signs with lower body predominance, were more frequent in patients with VP. Ninety-three % of PD patients had normal MRI, whereas all patients with VP had cerebral vascular lesions. UPDRS-II, -III scores at baseline were higher in VP than in PD patients and their increases throughout the follow-up period were more marked in VP than in PD patients.

CONCLUSIONS

Clinical history, symptoms, signs, response to therapy, and brain imaging help to differentiate PD and VP as two clinical entities with different clinical, prognostic and therapeutic implications, even if the coexistence of PD and a cerebral vascular disease in elderly patients is not infrequent and can make the diagnosis difficult.

Apraxia in movement disorders

The definition of apraxia specifies that the disturbance of performed skilled movements cannot be explained by the more elemental motor disorders typical of patients with movement disorders. Generally this does not present a significant diagnostic problem when dealing with 'higher-level' praxic disturbances (e.g. ideational apraxia), but it can be a major confound in establishing the presence of limb-kinetic apraxia. Most motor disturbances characteristic of extrapyramidal disorders, particularly bradykinesia and dystonia, will compromise the ability to establish the presence of loss of dexterity and deftness that constitutes this subtype. The term 'apraxia' has also been applied to other motor disturbances, such as 'gait apraxia' and 'apraxia of eyelid opening', that perhaps are misnomers, demonstrating the lack of a coherent nomenclature in this field. Apraxia is a hallmark of corticobasal degeneration (CBD) and historically this has received the most attention among the movement disorders. Corticobasal degeneration is characterized by various forms of apraxia affecting limb function, particularly ideomotor apraxia and limb-kinetic apraxia, although buccofacial and oculomotor apraxia can be present as well. The syndrome of parkinsonism and prominent apraxia, designated the 'corticobasal syndrome' (CBS), may be caused by a variety of other central nervous system pathologies including progressive supranuclear palsy (PSP), Alzheimer's disease, dementia with Lewy bodies and frontotemporal dementias. Distinct from the CBS, PSP and Parkinson's disease can demonstrate varying degrees of apraxia on selected tests, especially in those patients with more severe cognitive dysfunction. Diseases that cause the combination of apraxia and a primary movement disorder most often involve a variety of cerebral cortical sites as well as basal ganglia structures. Clinical-pathological correlates and functional imaging studies are compromised by both this diffuse involvement and the confusion experienced in the clinical evaluation of apraxia in the face of the additional elemental movement disorders. Finally, although apraxia results in clear disability in patients with the CBS, it is not clear how milder ideomotor apraxia found on specific testing contributes to patients' overall day-to-day motor disability.

From trepidant abasia to motor network failure--gait disorders as a consequence of subcortical vascular encephalopathy (SVE): review of historical and contemporary concepts

Gait disorders in progressive subcortical vascular encephalopathy (SVE) and their impact on the burden of disability in the growing elderly population are underrepresented in medical scientific literature. The absence of a clear framework for the diagnosis and classification for gait disorders on the basis of SVE has multiple reasons: (1) neither movement disorder specialists nor stroke specialists are truly familiar with this topic and feel responsible for its treatment, (2) the existing terminology lacks a clear concept and a consistent classification, and (3) only in recent years have large prospective trials started to address the natural course of SVE. This article reviews the classical descriptions of gait disturbances with preferential view to our present concept of SVE, and comments on historical and current nosology of gait disorders aiming to propose for a new classification.

Post-stroke movement disorders: report of 56 patients

BACKGROUND

Although movement disorders that occur following a stroke have long been recognised in short series of patients, their frequency and clinical and imaging features have not been reported in large series of patients with stroke.

METHODS

We reviewed consecutive patients with involuntary abnormal movements (IAMs) following a stroke who were included in the Eugenio Espejo Hospital Stroke Registry and they were followed up for at least one year after the onset of the IAM. We determined the clinical features, topographical correlations, and pathophysiological implications of the IAMs.

RESULTS

Of 1500 patients with stroke 56 developed movement disorders up to one year after the stroke. Patients with chorea were older and the patients with dystonia were younger than the patients with other IAMs. In patients with isolated vascular lesions without IAMs, surface lesions prevailed but patients with deep vascular lesions showed a higher probability of developing abnormal movements. One year after onset of the IAMs, 12 patients (21.4%) completely improved their abnormal movements, 38 patients (67.8%) partially improved, four did not improve (7.1%), and two patients with chorea died. In the nested case-control analysis, the patients with IAMs displayed a higher frequency of deep lesions (63% v 33%; OR 3.38, 95% CI 1.64 to 6.99, p<0.001). Patients with deep haemorrhagic lesions showed a higher probability of developing IAMs (OR 4.8, 95% CI 0.8 to 36.6).

CONCLUSIONS

Chorea is the commonest movement disorder following stroke and appears in older patients. Involuntary movements tend to persist despite the functional recovery of motor deficit. Deep vascular lesions are more frequent in patients with movement disorders.

Clinicopathological investigation of vascular parkinsonism, including clinical criteria for diagnosis

Vascular parkinsonism (VP) is difficult to diagnose with any degree of clinical certainty. We investigated the importance of macroscopic cerebral infarcts and pathological findings associated with microscopic "small vessel disease" (SVD) in the aetiology of VP. The severity of microscopic SVD pathology (perivascular pallor, gliosis, hyaline thickening, and enlargement of perivascular spaces) and the presence of macroscopically visible infarcts were assessed in 17 patients with parkinsonism and no pathological evidence of either Parkinson's disease or any histopathological condition known to be associated with a parkinsonian syndrome, and compared with age-matched controls. Microscopic SVD pathology was significantly more severe in the parkinsonian brains. Most patients presented with bilateral bradykinesia and rigidity together with a gait disorder characterised predominantly by a shuffling gait. Four patients presented acutely with hemiparesis and then progressed to develop a parkinsonian syndrome. They could be distinguished from the remaining VP patients by the presence at autopsy of macroscopically visible lacunar infarcts in regions where contralateral thalamocortical drive might be reduced. The clinical features at presentation varied according to the speed of onset and the underlying vascular pathological state. New clinical criteria for a diagnosis of VP are proposed based on the clinicopathological findings of this study.

Vascular parkinsonism

PURPOSE OF REVIEW

Vascular parkinsonism is a highly controversial concept since its first description by Critchley in 1929. There is no doubt that cerebrovascular disease can cause elements of parkinsonism. However, the extent of the spectrum of vascular parkinsonism remains quite imprecise. Here we review recent epidemiological, clinical, electrophysiological, morphological and functional brain imaging and pathological studies on 'vascular parkinsonism'.

RECENT FINDINGS

Epidemiological studies have demonstrated that vascular parkinsonism represents 3-5% of all cases of parkinsonism. The more specific clinical features are a history of stroke, lower body parkinsonism and poor levodopa response. Vascular risk factors are dominated by arterial hypertension, whereas others have been less evaluated. Vascular lesions within or outside the basal ganglia, unique and multiple, lacunae or territorial infarcts can be demonstrated by magnetic resonance imaging. Functional imaging of the dopaminergic pathway helps to differentiate vascular parkinsonism from idiopathic Parkinson's disease. However, none of these clinical or imaging criteria taken alone are specific for the diagnosis. A combination of convergent clinical and imaging clues are therefore necessary to improve the accuracy of the diagnosis, which is only certain when the pathology excludes underlying idiopathic Parkinson's disease.

SUMMARY

At present it remains unexplained why some patients develop vascular parkinsonism and others do not with the same apparent vascular lesion load. This will need further research along with the need to develop criteria to improve the accuracy of diagnosis of vascular parkinsonism. Vascular parkinsonism is also a research field on the relationships between vascular brain lesions and neurodegenerative disorders.

The effect of vascular disease on late onset Parkinson's disease

The clinical severity of late onset Parkinson's disease (PD) varies from patient to patient and it is further complicated by the increasing prevalence of accompanying disorders in the elderly. We set out to study the impact of ischemic heart disease, minor stroke, hypertension and diabetes mellitus in a group of late onset PD patients (age >or=70 years). Consecutive late onset PD patients seen in the Department of Neurology, Medical School of Patras, Greece were included in this study. We used very strict criteria to eliminate the possibility of including patients with vascular parkinsonism. Comparisons were made between groups of patients suffering with idiopathic Parkinson's disease (IPD) and the above-mentioned diseases. One hundred and sixty-seven consecutive late onset PD patients were included in this study. The most common accompanying disorders in our group were hypertension in 31 (18%) of the patients and minor stroke in 20 (12%). The Hoen and Yahr score in late onset IPD patients who suffered from minor stroke, ischemic heart disease or diabetes mellitus was significantly higher when compared with patients without the above disorders. The results clearly suggest that the presence of vascular disease on an IPD patient may aggravate PD severity. In clinical grounds, these findings can be proved significant since early and aggressive prevention of vascular disease and treatment of vascular risk may contribute in controlling symptom severity in PD.

The L-dopa response in vascular parkinsonism

OBJECTIVE

To determine whether a positive L-dopa response in vascular parkinsonism (VP) is correlated with the presence of nigrostriatal pathology due to either vascular damage or neuronal cell loss.

METHODS

Seventeen patients with pathologically confirmed VP were selected from the pathological collection of the Queen Square Brain Bank for Neurological Disorders, and their L-dopa response during life was compared with the presence of macroscopic vascular damage in the nigrostriatal pathway and microscopic substantia nigra cell loss.

RESULTS

Ten of the twelve patients with a good or excellent response had macroscopic infarcts or lacunae caused by enlarged perivascular spaces in the basal ganglia or microscopic neuronal cell loss in the substantia nigra. In contrast, only one of the five patients with a moderate or no response had lacunae in the putamen, and none had lacunar infarcts or substantia nigra cell loss.

CONCLUSION

These results suggest that a substantial number of patients with clinically suspected VP may respond with benefit to dopaminergic therapy, especially those with lesions in or close to the nigrostriatal pathway.

Vascular parkinsonism: clinical correlates predicting motor improvement after lumbar puncture

Vascular parkinsonism (VP) is a poorly defined entity which has clinical, and perhaps pathological, overlap with other diagnoses. Although classical VP involves lesions of the basal ganglia, the majority of cases actually show diffuse subcortical white matter changes (SCWMC) on imaging. The exact pathologies of these white matter changes are debated and likely heterogeneous, but are generally thought to represent areas of chronic or recurrent partial ischemia. Cerebrospinal fluid (CSF) drainage is the treatment for NPH and has been reported to improve symptoms in some patients with idiopathic NPH and associated SCWMC. To determine whether historical, clinical, or radiographic factors predict improvement in VP patients after CSF drainage, we removed 35-40 ml of CSF via lumbar punctures (LP) from 40 patients and compared responders with nonresponders for a variety of demographics, clinical features, and blindly interpreted magnetic resonance images (MRI). Fifteen patients (37.5%) reported "significant and irrefutable" gait improvement after LP. Twelve (30.0%) reported no effect and 13 (32.5%) reported mild or very transient improvement. Timed gait in a subset of patients improved (P < 0.05) immediately after LP. Clinically, improvement after CSF removal was predicted by any positive response to levodopa (P < 0.001), the lack of vertical gaze palsies (P < 0.05), the lack of a pure freezing gait (P < 0.05), and the lack of hypotensive episodes (P < 0.05). Blinded MRI interpretation did not find features which clearly predicted response. Some patients diagnosed with VP improved after LP. Clinically, these patients tended to resemble idiopathic PD, whereas nonresponders more closely resembled progressive supranuclear palsy (PSP). These results warrant further investigation and also raise the possibility of testing CSF drainage in patients with idiopathic PD complicated by SCWMC.

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.

Vascular Parkinsonism: a case report and review of the literature

Vascular Parkinsonism (VP) is characterised by sudden onset and rapid progression of clinical symptoms, absent or poor response to dopamine substitution therapy, and postural instability with shuffling gait and absence of tremor, making it a clinically distinct entity from idiopathic Parkinson's disease (IPD). Furthermore, it displays certain typical findings in neurological investigations. We report on a patient presenting features of VP associated with an intracerebral lesion not ascribed to VP to date, namely an isolated ischaemic focal lesion located in the left cerebral peduncle between the substantia nigra and nucleus ruber as evidenced by magnetic resonance imaging (MRI). The pathophysiological organic correlate for contralateral extrapyramidal symptoms in this patient may be an interruption of nigro-thalamic projection, interrupting the final subcortical station in the cortic-striato-pallido-nigro-thalamico-cortical loop central to the pathophysiology of parkinsonian syndromes. Non-response t o levodopa therapy could be a consequence of disruption of the cortico-basal ganglia-cortical loop on account of ischaemic destruction of subcortico-cortical axons, the underlying pathology, therefore, not being the result of a loss of nigral dopaminergic neurons or striatal dopamine deficiency pathogonomonic of IPD. To our knowledge, this is the first case of clinically manifest VP to be described with a single lesion in the contralateral cerebral peduncle between the substantia nigra and nucleus ruber, and suggests alternative intracerebral patterns for the distribution of disease-causing lesions in VP, and possibly new pathophysiological explanations for the nature of this disease.

Freezing episodes in hemiparetic stroke: results of a pilot survey

OBJECTIVE

To determine whether freezing episodes commonly occur in patients who have had a hemiparetic stroke.

DESIGN

A postal questionnaire sent to 108 patients who had been admitted to our Stroke Unit with a hemiparesis due to an acute ischaemic stroke or a primary intracerebral haemorrhage.

RESULTS

Ninety-three questionnaires were returned, of which 14 were unsuitable for analysis as the patients were unable to walk. The remaining 79 questionnaires were analysed (response rate 73%). Twenty-six (33%) patients reported freezing episodes while walking.

CONCLUSIONS

Freezing episodes have been underappreciated in patients who have had a hemiparetic stroke. This is potentially important as these patients may benefit from some of the rehabilitation techniques currently being developed for patients with cerebral multi-infarct states who have similar gait problems. Future studies should be more widely based and designed to characterize the nature of the freezing episodes and their relationship to the location of the lesion.

Aging and cerebrovascular disease

Aging influences cerebrovascular disease expression by a variety of mechanisms. Age-related changes in cerebral autoregulation, cellular metabolism, the blood-brain barrier, and autonomic function may leave the cerebrovascular system vulnerable to injury. Certain cerebrovascular disease, such as atrial fibrillation, watershed infarctions, carotid artery atherosclerosis, cerebral hemorrhages, subdural hematomas, and transient global amnesia manifest in the elderly. Vascular dementia and white matter disease are better understood with newer neuroimaging studies, careful neuropsychological and histopathologic examinations. Atherosclerosis and cerebral amyloid angiopathy may have larger roles than previously understood in Alzheimer's disease.

Costs of drug treatment in Parkinson's disease

Parkinson's disease (PD) has a major socioeconomic impact on society. The chronic, progressive course of the disease, which often leads to severe disability, results in high expenses for the medical resources used for treatment, care, and rehabilitation of patients as well as reduced or lost productivity as a result of illness or premature death. In Great Britain, it has been estimated that the National Health Service spends up to 383 million pound sterling (1992) annually for the care of PD. This emphasizes the importance of assessing the costs related to this disease. A detailed knowledge of the cost allocation would provide a solid basis on which health care priorities can be rationally set. Next to hospitalization, drug treatment accounts for the highest expense for direct medical costs of PD. Therefore, this analysis focuses on the costs of drug treatment for PD. The cost analysis was based on a retrospective study of 409 patients with PD who were seen over a 1-year period in our movement disorders clinic. The cost of therapy varied considerably depending on the severity of the condition (assessed in the "off" phase), the incidence of motor fluctuations, and the type of PD. In the early stage of the disease (Hoehn and Yahr stage I [HY I]), mean daily costs for therapy were DM (German marks) 6.60, which increased in later stages of the disease (HY V) to DM 22.00. If rare cases requiring continuous subcutaneous apomorphine infusion were included, mean daily costs of patients in HY V rose to DM 32.50 (the mean daily costs of subcutaneous apomorphine-treated patients in HY V: DM 74.30). Patients with motor fluctuations accounted for higher costs (DM 16.50) compared with those without motor fluctuations (DM 7.80). With respect to the three subtypes of PD, the mean daily expenditure was DM 7.00 for the tremor-dominant type, DM 12.40 for the akinetic-rigid type, and DM 10.80 for the mixed type. In the group of 409 PD patients included in this analysis, the average daily expenditure for drug treatment totaled DM 10.70 per patient (including patients on subcutaneous apomorphine).

Striatal infarction in the rat causes a transient reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra

Dopaminergic neurons of the substantia nigra pars compacta were examined in the rat brain following striatal infarction subsequent to transient focal cerebral ischemia. Rats had the middle cerebral artery occluded for 2 h or were sham-operated, and tyrosine hydroxylase immunoreactivity was evaluated by Western blot and immunohistochemistry at different times ranging from 1 to 60 days after ischemia. The number of tyrosine hydroxylase-immunoreactive cells in the substantia nigra pars compacta was counted under the light microscope and compared to that in the contralateral side and controls. No changes of tyrosine hydroxylase immunoreactivity were detected in the ipsilateral versus the contralateral substantia nigra of sham-operated rats or 1 day after ischemia. However, a statistically significant reduction of tyrosine hydroxylase-immunoreactive cells became apparent in the ipsilateral compared with the contralateral substantia nigra at 7 and 14 days after ischemia. This reduction showed a clear recovery at 30 days after ischemia, and no signs of difference between the ipsilateral and the contralateral side were apparent by 60 days. Therefore, the reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra was only transiently seen from 1 to 2 weeks following ischemia. The observed loss of tyrosine hydroxylase was not accompanied by signs of cell death or gliosis in the ipsilateral pars compacta. The present results show a transitory reduction of tyrosine hydroxylase immunoreactivity in the ipsilateral substantia nigra pars compacta after focal ischemia and suggest that striatal infarction causes a transient deficit of dopaminergic function.