Long-term follow-up of subthalamic nucleus deep brain stimulation in patients with Parkinson's disease: An analysis of survival and disability milestones

BACKGROUND

Data on the long-term survival and incidence of disability milestones after subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) is limited.

OBJECTIVES

To estimate mortality and assess the frequency/time-to-development of disability milestones (falls, freezing, hallucinations, dementia, and institutionalization) among PD patients post STN-DBS.

METHODS

A longitudinal retrospective study of patients undergoing STN-DBS. For mortality, Cox proportional hazards regression analysis was performed. For disease milestones, competing risk analyses were performed and cumulative incidence functions reported. The strength of association between baselines features and event occurrence was calculated based on adjusted hazard ratios.

RESULTS

The overall mortality for the 109 patients was 16 % (62.1 ± 21.3 months after surgery). Falls (73 %) and freezing (47 %) were both the earliest (40.4 ± 25.4 and 39.6 ± 28.4 months, respectively) and most frequent milestones. Dementia (34 %) and hallucinations (32 %) soon followed (56.2 ± 21.2 and mean 60.0 ± 20.7 months after surgery, respectively). Higher ADL scores in the OFF state and higher age at surgery were associated with falls, freezing, dementia and institutionalization.

CONCLUSIONS

Long-term mortality rate is low after STN-DBS. Disease milestones occur later during the disease course, with motor milestones appearing first and at a higher frequency than cognitive ones.

A distinct neuromelanin magnetic resonance imaging pattern in parkinsonian multiple system atrophy

Background

Parkinsonian variant of multiple system atrophy is a neurodegenerative disorder frequently misdiagnosed as Parkinson’s disease. No early imaging biomarkers currently differentiate these disorders.

Methods

Simple visual imaging analysis of the substantia nigra and locus coeruleus in neuromelanin-sensitive magnetic resonance imaging and nigrosome 1 in susceptibility-weighted sequences was performed in thirty patients with parkinsonian variant of multiple system atrophy fulfilling possible/probable second consensus diagnostic criteria. The neuromelanin visual pattern was compared to patients with Parkinson’s disease with the same disease duration (n = 10) and healthy controls (n = 10). Substantia nigra semi-automated neuromelanin area/signal intensity was compared to the visual data.

Results

Groups were similar in age, sex, disease duration, and levodopa equivalent dose. Hoehn & Yahr stage was higher in parkinsonian multiple system atrophy patients, 69% of whom had normal neuromelanin size/signal, significantly different from Parkinson’s disease patients, and similar to controls. Nigrosome 1 signal was lost in 74% of parkinsonian multiple system atrophy patients. Semi-automated neuromelanin substantia nigra signal, but not area, measurements were able to differentiate groups.

Conclusions

In patients with parkinsonism, simple visual magnetic resonance imaging analysis showing normal neuromelanin substantia nigra and locus coeruleus, combined with nigrosome 1 loss, allowed the distinction of the parkinsonian variant of multiple system atrophy from Parkinson’s disease and healthy controls. This easy and widely available method was superior to semi-automated measurements in identifying specific imaging changes in substantia nigra and locus coeruleus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-020-02007-5.

Risk of Developing Parkinson Disease in Bipolar Disorder: A Systematic Review and Meta-analysis

Importance

Parkinson disease (PD) manifests by motor and nonmotor symptoms, which may be preceded by mood disorders by more than a decade. Bipolar disorder (BD) is characterized by cyclic episodes of depression and mania. It is also suggested that dopamine might be relevant in the pathophysiology of BD.

Objective

To assess the association of BD with a later diagnosis of idiopathic PD.

Data Sources

An electronic literature search was performed of Cochrane Controlled Register of Trials, MEDLINE, Embase, and PsycINFO from database inception to May 2019 using the terms Parkinson disease, bipolar disorder, and mania, with no constraints applied.

Study Selection

Studies that reported data on the likelihood of developing PD in BD vs non-BD populations were included. Two review authors independently conducted the study selection.

Data Extraction and Synthesis

Two review authors independently extracted study data. Data were pooled using a random-effects model, results were abstracted as odds ratios and 95% CIs, and heterogeneity was reported as I2.

Main Outcome and Measures

Odds ratios of PD.

Results

Seven studies were eligible for inclusion and included 4 374 211 participants overall. A previous diagnosis of BD increased the likelihood of a subsequent diagnosis of idiopathic PD (odds ratio, 3.35; 95% CI, 2.00-5.60; I2 = 92%). A sensitivity analysis was performed by removing the studies that had a high risk of bias and also showed an increased risk of PD in people with BD (odds ratio, 3.21; 95% CI, 1.89-5.45; I2 = 94%). Preplanned subgroup analyses according to study design and diagnostic certainty failed to show a significant effect.

Conclusions and Relevance

This review suggests that patients with BD have a significantly increased risk of developing PD compared with the general population. Subgroup analyses suggested a possible overestimation in the magnitude of the associations. These findings highlight the probability that BD may be associated with a later development of PD and the importance of the differential diagnosis of parkinsonism features in people with BD.

Patients and Health Professional's Perspective of Functional Mobility in Parkinson's Disease

Background: Functional mobility (FM) is the person's ability to move to accomplish daily living tasks and activities. FM limitations are common in Parkinson's disease, increase with disease progression, and can be highly disabling. Although several studies in Parkinson's disease (PD) field use this concept, only recently, a formal definition has been proposed.

Objective: We aimed to explore patient's and health professional's perspectives of FM in PD.

Methods: A focus group methodology has been used. Four focus groups, with a total of 10 patients and 10 health professionals, were performed. Six patients were early stage and four advanced stage. The health professional's group was composed of five neurologists and five physiotherapists. The suitability of the new concept, the impact of FM limitations in PD patient's daily routine, and the potential benefit of walking aids have been discussed.

Results: All participants were able to provide a spontaneous definition of FM, matching with the proposed concept. All agreed that PD affects patient's FM, increasing the limitations with disease progression, and with the existence of a serious prejudice with walking aids that hinders its use. Early-stage patient's perspective seems to be more in line with neurologist's perspective, while the views of advanced-stage patients were closer to physiotherapist's views.

Conclusion: FM concept was considered as intuitive and useful. FM limitations have an important physical and social impact in the advanced stage of the disease. Although patients and health professionals acknowledge walking aid's benefit improving patient's FM, the prejudice associated with this type of tools limits its recommendation and use.

Moving towards home-based community-centred integrated care in Parkinson's disease

People living with Parkinson's disease (PwP) experience a wide range of motor and non-motor symptoms associated with increasing complexity of care delivery. A multispecialty approach has been presented as an intuitive solution for tailored and comprehensive care delivery. Nevertheless, past trials of both multidisciplinary or interdisciplinary care models in PD suggested no measurable change to a small benefit in quality of life (QoL) and failed to show economic sustainability. We propose a home-based community-centred integrated care (iCARE-PD) for PwP as a pragmatic solution to harness the potential of existing care resources using an integrated care strategy, enable self-management support and implement technology-enabled care. The iCARE-PD model is based on Freeman's concept of continuity of care and the expanded Chronic Care Model for organization of care strategies. A home-based community-centred integrated care has immediate implications for clinical practice, with potential benefits in rural areas or lower-income countries, by enhancing access to care with optimized costs. There is a need to establish which and how interventions may be used as an instrument of care in each local deployment of the iCARE-PD model. We put forward a multidisciplinary framework to generate the evidence supportive of its implementation as the standard of care in the future and delineate the core strategies to secure the implementation of this care approach across different health care systems to ensure feasibility and economic sustainability. We envision this model becoming a paradigm of personalized care transferable to people with atypical forms of neurodegenerative parkinsonism.

Anterior Limb of Internal Capsule and Bed Nucleus of Stria Terminalis Stimulation for Gilles de la Tourette Syndrome with Obsessive-Compulsive Disorder in Adolescence: A Case of Success

Gilles de la Tourette syndrome (GTS) is a neurobehavioral disorder comprising motor and vocal tics. In most cases it is associated with other disorders such as obsessive-compulsive disorder (OCD). In refractory cases deep brain stimulation (DBS) is a valid treatment option. This paper describes the case of a 15-year-old adolescent with an extremely refractory GTS with associated OCD. The patient developed catatonia associated with OCD, which partially remitted after electroconvulsive therapy. At the peak of the disease the Yale Global Tic Severity Scale (YGTSS) was 100 and the patient required sedation and intubation. All medical treatment options were unsuccessful. Bilateral DBS of the anterior limb of internal capsule (ALIC)/bed nucleus of stria terminalis (BST) region was performed, using a target below the BST and a trajectory through the ALIC, with stimulation of contacts 0 and 3. Two weeks after surgery sedatives were suspended and the patient was successfully extubated. One year after surgery the patient reached a YGTSS of 19, representing an 81% improvement. OCD completely resolved. Adverse events were a superficial infection and weight gain. In conclusion, this ALIC/BST stimulation appears to have been an effective and safe treatment for GTS with OCD in this case. Young age should not be an exclusion criterion for DBS in severe GTS and OCD. Further studies should be pursued for this target.

Inhaled levodopa for intermittent treatment of OFF episodes in patients with Parkinson's disease

Introduction: Many patients with advanced Parkinson's disease (PD) have inadequate control of motor symptoms despite optimized treatment. Predictable and unpredictable OFF periods severely interfere with the quality of life. A drug that easily and rapidly reverts the OFF state is still needed. Subcutaneous apomorphine, the only approved drug for this indication, although efficacious, is not widely used probably due to its potential side effects and complicated administration.Levodopa is the most efficacious drug for the treatment of PD motor symptoms. However, issues related to the oral route and intestinal absorption in later disease stages render this route lengthy and inefficacious.Areas covered: Literature on the development of an inhaled formulation of levodopa has been reviewed. Significant advances in the field of pulmonary delivery systems and in dry powders have enabled the development of a new formulation of levodopa that can be inhaled and adequate blood levels rapidly achieved, bypassing intestinal absorption. Several clinical trials have reported efficacy, safety, and tolerability data. Some pulmonary-related adverse events have been reported but are mostly mild.Expert opinion: This new way of administering levodopa is likely to be very welcome and may fill a gap for OFF rescue treatments, at least for some patients.

Measurement Instruments to Assess Functional Mobility in Parkinson's Disease: A Systematic Review

Background

Functional mobility (FM) is a person's ability to move to accomplish activities of daily living; it bridges the concepts of mobility and functional ability. There is frequently a loss of FM in Parkinson's disease (PD). Several instruments have been used to assess this concept in PD; however, there is no consensus on which are the most appropriate.

Objective

We aimed to identify and critically appraise which measurement instruments have been used to assess FM.

Methods

A systematic review was conducted using the databases CENTRAL, MEDLINE, Embase, and PEDro from their inception to January 2019 to identify all observational and experimental studies conducted in PD or atypical parkinsonism that included an FM assessment. Two reviewers independently screened citations, extracted data, and assessed clinimetric properties.

Results

We included 95 studies that assessed FM in PD. Fifty-five (57.9%) studies mentioned FM in the article, and 39 (41.1%) specified the measurement tools used to evaluate FM. FM was the primary outcome in 12 (12.6%) studies. The Timed Up and Go test was the most frequently used measurement tool. Only one study presented a definition of FM. Several overlapping terms were used, the most common being mobility.

Conclusion

Several studies reported the use of FM measurement tools in PD, though with frequent misconceptions, an inadequate context of use, or suboptimal assessment. We propose the establishment of the concept of FM applied to PD, followed by the adequate clinimetric validation of existing measurement tools to provide a comprehensive and reliable evaluation of FM in PD.

Physical Activity, Exercise, and Physiotherapy in Parkinson's Disease: Defining the Concepts

Background

Exercise is gaining extreme relevancy as a new therapeutic intervention for Parkinson's disease (PD). However, the frequent misuse of the concepts exercise, physiotherapy, and physical activity limits the possibility of summarizing research findings. This review aims to clarify these concepts and summarize the evidence on exercise in PD.

Methods

We critically appraised physical activity-related concepts and conducted a systematic review of clinical trials evaluating exercise interventions in PD. Additionally, we discussed the implications for PD clinical practice and research.

Results

Exercise is a subset of physical activity, and a major component of physiotherapy for PD management, having as the main goal to improve physical fitness. The appraisal of the 83 identified clinical trials found high variability in exercise interventions. Multimodal exercise was the most studied, and 60 minutes, two times/week for 12 weeks, the most reported prescription parameters.

Conclusion

The best available evidence recommends increasing physical activity levels in PD. Exercise and physiotherapy programs seem the most efficacious strategies to achieve this goal. As a result of the heterogeneity in the type and manner exercise is prescribed, it is not possible to propose strong recommendations for exercise in PD. We believe that, in addition to the clarification of concepts here presented, a collaborative and rigorous work of different areas of knowledge is needed.

Should the Energy Contribution of Commercial Thickeners Be Considered in the Nutrition Plan of Patients With Dysphagia?

BACKGROUND

Clinical management options for dysphagia include the use of thickeners to increase the consistency of liquids. Health professionals may not be aware of the nutrition value of these products, since there are no such recommendation in clinical guidelines. Our aim was to estimate the added nutrition value of the 2 types of commercial thickeners (starch and xanthan gum) to daily nutrition intake and compare their nutrition value for nectar, honey, and pudding consistencies. Additionally, we compared the nutrition value of both thickeners with a high-energy powder, since they share the same main ingredients.

METHODS

We collected recommended dosages for obtaining the 3 different consistencies and nutrition content from the technical food labels. Daily intake of fluids was estimated from the Portuguese National Food, Nutrition and Physical Activity Survey. Total daily amount of thickener needed was estimated, as well as their correspondent nutrition contributions.

RESULTS

Estimated daily fluid intake was 2439 mL. Starch thickeners provide significantly more energy at all consistencies than xanthan gum provides (423-846 kcal, P < 0.05, and 103-308 kcal, P < 0.05, respectively). Significantly more fiber is provided by xanthan gum thickeners (9 g in nectar and 27 g in pudding consistencies, P < 0.05). Median energy and carbohydrate values per 100 g of high-energy powder modules and starch thickeners are similar.

CONCLUSION

The nutrition value of thickeners should be routinely considered in the nutrition assessment and planning of patients with dysphagia for liquids, since they contribute significantly with energy, carbohydrate, and fiber.

The launch of opicapone for Parkinson's disease: negatives versus positives

INTRODUCTION

Opicapone is a novel, third generation COMT inhibitor approved for the treatment of Parkinson's disease. Safety and tolerability data is critical to determine the benefit-harm balance and anticipate therapeutic adherence. Areas covered: This review evaluates the tolerability and safety profile of opicapone. These data were extracted from all published clinical trials, including preclinical, phase I, phase II and phase III studies as well as postmarketing data. Opicapone was safe and well tolerated, with frequencies of treatment-emergent adverse events similar to placebo. Expert opinion: Opicapone have shown a good safety and tolerability profile. This adds to its proven efficacy and convenient once-daily administration, supporting a role of opicapone as a first-line therapy for motor complications in Parkinson's disease patients.

Clinical rating scale for pantothenate kinase-associated neurodegeneration: A pilot study

BACKGROUND

Pantothenate kinase-associated neurodegeneration is a progressive neurological disorder occurring in both childhood and adulthood. The objective of this study was to design and pilot-test a disease-specific clinical rating scale for the assessment of patients with pantothenate kinase-associated neurodegeneration.

METHODS

In this international cross-sectional study, patients were examined at the referral centers following a standardized protocol. The motor examination was filmed, allowing 3 independent specialists in movement disorders to analyze 28 patients for interrater reliability assessment. The scale included 34 items (maximal score, 135) encompassing 6 subscales for cognition, behavior, disability, parkinsonism, dystonia, and other neurological signs.

RESULTS

Forty-seven genetically confirmed patients (30 ± 17 years; range, 6-77 years) were examined with the scale (mean score, 62 ± 21; range, 20-106). Dystonia with prominent cranial involvement and atypical parkinsonian features were present in all patients. Other common signs were cognitive impairment, psychiatric features, and slow and hypometric saccades. Dystonia, parkinsonism, and other neurological features had a moderate to strong correlation with disability. The scale showed good internal consistency for the total scale (Cronbach's α = 0.87). On interrater analysis, weighted kappa values (0.30-0.93) showed substantial or excellent agreement in 85% of the items. The scale also discriminated a subgroup of homozygous c.1583C>T patients with lower scores, supporting construct validity for the scale.

CONCLUSIONS

The proposed scale seems to be a reliable and valid instrument for the assessment of pediatric and adult patients with pantothenate kinase-associated neurodegeneration. Additional validation studies with a larger sample size will be required to confirm the present results and to complete the scale validation testing. © 2017 International Parkinson and Movement Disorder Society.

Critical appraisal of clinical trials in multiple system atrophy: Toward better quality

Multiple system atrophy (MSA) is a rare neurodegenerative disease of undetermined cause. Although many clinical trials have been conducted, there is still no treatment that cures the disease or slows its progression. We sought to assess the clinical trials, methodology, and quality of reporting of clinical trails conducted in MSA patients. We conducted a systematic review of all trials with at least 1 MSA patient subject to any pharmacological/nonpharmacological interventions. Two independent reviewers evaluated the methodological characteristics and quality of reporting of trials. A total of 60 clinical trials were identified, including 1375 MSA patients. Of the trials, 51% (n = 31) were single-arm studies. A total of 28% (n = 17) had a parallel design, half of which (n = 13) were placebo controlled. Of the studies, 8 (13.3%) were conducted in a multicenter setting, 3 of which were responsible for 49.3% (n = 678) of the total included MSA patients. The description of primary outcomes was unclear in 60% (n = 40) of trials. Only 10 (16.7%) clinical trials clearly described the randomization process. Blinding of the participants, personnel, and outcome assessments were at high risk of bias in the majority of studies. The number of dropouts/withdrawals was high (n = 326, 23.4% among the included patients). Overall, the design and quality of reporting of the reviewed studies is unsatisfactory. The most frequent clinical trials were small and single centered. Inadequate reporting was related to the information on the randomization process, sequence generation, allocation concealment, blinding of participants, and sample size calculations. Although improved during the recent years, methodological quality and trial design need to be optimized to generate more informative results. © 2017 International Parkinson and Movement Disorder Society.

Asthma-chronic obstructive pulmonary disease overlap syndrome - Literature review and contributions towards a Portuguese consensus

INTRODUCTION

Phenotypic overlap between the two main chronic airway pulmonary diseases, asthma and chronic obstructive pulmonary disease (COPD), has been the subject of debate for decades, and recently the nomenclature of asthma-COPD overlap syndrome (ACOS) was adopted for this condition. The definition of this entity in the literature is, however, very heterogeneous, it is therefore important to define how it applies to Portugal.

METHODS

A literature review of ACOS was made in a first phase resulting in the drawing up of a document that was later submitted for discussion among a panel of chronic lung diseases experts, resulting in reflexions about diagnosis, treatment and clinical guidance for ACOS patients.

RESULTS

There was a consensus among the experts that the diagnosis of ACOS should be considered in the concomitant presence of: clinical manifestations characteristic of both asthma and COPD, persistent airway obstruction (post-bronchodilator FEV₁/FVC<0.7), positive response to bronchodilator test (increase in FEV₁ of ≥200mL and ≥12% from baseline) and current or past history of smoking or biomass exposure. In reaching diagnosis, the presence of peripheral eosinophilia (>300eosinophils/μL or >5% of leukocytes) and previous history of atopy should also be considered. The recommended first line pharmacological treatment in these patients is the ICS/LABA association; if symptomatic control is not achieved or in case of clinical severity, triple therapy with ICS/LABA/LAMA may be used. An effective control of the exposure to risk factors, vaccination, respiratory rehabilitation and treatment of comorbidities is also important.

CONCLUSIONS

The creation of initial guidelines on ACOS, which can be applied in the Portuguese context, has an important role in the generation of a broad nationwide consensus. This will give, in the near future, a far better clinical, functional and epidemiological characterization of ACOS patients, with the ultimate goal of achieving better therapeutic guidance.

Longstanding spastic paraparesis in a patient infected with hepatitis C virus and seropositive for aquaporin-4 antibody - Case report and review of the literature

Nervous system involvement in Hepatitis C virus infection (HCV) has been associated to neuro-immunological deregulation, particularly in interferon-alpha treated patients. We present a case of optic and brainstem demyelinating disorder associated with aquaporin-4 (AQP4) antibodies. A 48 year-old woman, with previous diagnosis of non-treated hepatitis C, presented with a 10-year history of long-standing gait disturbance. Neurological examination disclosed a grade 4 spastic paraparesis, lower limb hyperreflexia, right positive Hoffmann sign, bilateral Babinski sign and spastic gait only possible with bilateral support. Spinal cord magnetic resonance imaging (MRI) was normal. Brain MRI showed an asymmetric, bilateral pontine and left mesencephalic hypersignal in T2 and FLAIR, with no gadolinium enhancement. Visual evoked potential revealed bilateral pre-chiasmatic conduction delay. Blood tests showed a positive anti-HCV antibody and a positive AQP4 antibody. Cerebrospinal fluid (CSF) analysis was normal, with no oligoclonal bands. The patient started intravenous (IV) methylprednisolone followed by oral prednisolone; simultaneously, interferon-alpha and ribavirin. There was a slight clinical improvement within the first weeks. There are 7 cases describing association between HCV infection and central nervous system (CNS) demyelination with positive AQP4 antibody, 4 patients under interferon-α. AQP4 antibodies should be tested in patients infected with HCV and CNS demyelination.

Pharmacological interventions for daytime sleepiness and sleep disorders in Parkinson's disease: Systematic review and meta-analysis

BACKGROUND

Daytime sleepiness and sleep disorders are frequently reported in Parkinson's disease (PD). However, their impact on quality of life has been underestimated and few clinical trials have been performed.

OBJECTIVES

We aimed to assess the efficacy and safety of pharmacological interventions for daytime sleepiness and sleep disorders in PD.

METHODS

Systematic review of randomized controlled trials comparing any pharmacological intervention with no intervention or placebo for the treatment of daytime sleepiness and sleep problems in PD patients.

RESULTS

Ten studies (n = 338 patients) were included. Four trials addressed interventions for excessive daytime sleepiness. Meta-analysis of the three trials evaluating modafinil showed a significant reduction in sleepiness, as assessed by the Epworth Sleepiness Scale (ESS) (- 2.24 points, 95% CI - 3.90 to - 0.57, p < 0.05). In one study, treatment with caffeine was associated with a non-significant improvement of 1.71 points in ESS (95% CI, - 3.57 to 0.13). The six remaining trials assessed interventions for insomnia and REM sleep Behaviour Disorder (RBD). Single study results suggest that doxepin and YXQN granules might be efficacious, while pergolide may be deleterious for insomnia and that rivastigmine may be used to treat RBD in PD patients. However, there is insufficient evidence to support or refute the efficacy of any of these interventions. No relevant side effects were reported.

CONCLUSIONS

Whilst providing recommendations, this systematic review depicts the lack of a body of evidence regarding the treatment of sleep disorders in PD patients; hence, further studies are warranted.

Cerebral Amyloid Angiopathy Associated with Inflammation: Report of 3 Cases and Systematic Review

INTRODUCTION

Cerebral amyloid angiopathy associated with inflammatory process (CAA-I) is a rare potentially treatable encephalopathy, characterized by an inflammatory response to vascular deposits of β-amyloid. We aimed to describe 3 clinical cases and perform a systematic review of all neuropathologically proved CAA-I case reports to describe its clinical and pathologic features and outcome under different treatments.

METHODS

We searched PubMed and Cochrane Library and screened references of included studies and review articles for additional citations. Outcome was classified at the last available follow-up by the modified Rankin Scale (mRS).

RESULTS

A total of 67 publications, reporting on 155 patients, were included. Mean age was 66.9 years, and 53.5% were men. The most common clinical presentation was cognitive dysfunction (48.0%) followed by headaches (38.7%), seizures (36.7%), and pyramidal signs (20.0%). Perivascular and vasculitic inflammation with granuloma was the most common pathologic pattern (27.5%). Eighty-six percent were treated with corticosteroids and 33.9% with cyclophosphamide. Forty-two percent regained independence (mRS score 0-2), whereas 20.5% were left with a severe handicap (mRS score 3-5) and 37.5% died. There were no statistically significant differences in outcome between patients treated with therapy with corticosteroids alone comparing with those treated with combination corticosteroids with cytostatic agents.

CONCLUSIONS

The most common clinical manifestation of CAA-I was cognitive dysfunction. The functional outcome was unfavorable in the majority of the patients, with death or severe disability in almost two third of the cases, despite treatment. No differences in outcome could be detected between patients treated with corticosteroids versus patients treated with cytostatics, combined with corticosteroids.

CT scan correlates of gesture recognition

The ability to recognise gestures was studied in 65 left-hemispheric stroke patients whose lesions were located by CT scan. In the acute stage (first month) frontal lobe and basal ganglia were frequently involved in patients showing inability to recognise gestures. In the later (third to fourth month) and chronic stages (greater than 6 months) parietal lobe involvement was important; lesions causing gesture recognition impairment were larger, had more extensive and frequent parietal involvement and produced less temporal lobe damage than those causing aural comprehension defects. These findings are discussed in the light of recent models of cerebral localisation of complex functions.