Dysarthria due to Supratentorial and Infratentorial Ischemic Stroke: A Diffusion-Weighted Imaging Study

Variations on the theme: focus on cerebellum and emotional processing

The cerebellum operates exploiting a complex modular organization and a unified computational algorithm adapted to different behavioral contexts. Recent observations suggest that the cerebellum is involved not just in motor but also in emotional and cognitive processing. It is therefore critical to identify the specific regional connectivity and microcircuit properties of the emotional cerebellum. Recent studies are highlighting the differential regional localization of genes, molecules, and synaptic mechanisms and microcircuit wiring. However, the impact of these regional differences is not fully understood and will require experimental investigation and computational modeling. This review focuses on the cellular and circuit underpinnings of the cerebellar role in emotion. And since emotion involves an integration of cognitive, somatomotor, and autonomic activity, we elaborate on the tradeoff between segregation and distribution of these three main functions in the cerebellum.

Clinicopathological associations of hemispheric dominance in primary progressive apraxia of speech

OBJECTIVE

Primary progressive apraxia of speech (PPAOS) is associated with imaging abnormalities in the lateral premotor cortex (LPC) and supplementary motor area (SMA). It is not known whether greater involvement of these regions in either hemisphere is associated with demographics, presenting, and/or longitudinal features.

METHODS

In 51 prospectively recruited PPAOS patients who completed [18 F]-fluorodeoxyglucose (FDG) positron emission tomography (PET), we classified patients as left-dominant, right-dominant, or symmetric, based on visual assessment of the LPC and SMA on FDG-PET. SPM and statistical analyses of regional metabolic values were performed. Diagnosis of PPAOS was made if apraxia of speech was present and aphasia absent. Thirteen patients completed ioflupane-123I (dopamine transporter [DAT]) scans. We compared cross-sectional and longitudinal clinicopathological, genetic, and neuroimaging characteristics across the three groups, with area under the receiver-operating curve (AUROC) determined as a measure of effect size.

RESULTS

In all, 49% of the PPAOS patients were classified as left-dominant, 31% as right-dominant, and 20% as symmetric, which was supported by results from the SPM and regional analyses. There were no differences in baseline characteristics. Longitudinally, right-dominant PPAOS showed faster rates of progression of ideomotor apraxia (AUROC 0.79), behavioral disturbances (AUROC 0.84), including disinhibition symptoms (AUROC 0.82) and negative behaviors (AUROC 0.82), and parkinsonism (AUROC 0.75) compared to left-dominant PPAOS. Symmetric PPAOS showed faster rates of dysarthria progression compared to left-dominant (AUROC 0.89) and right-dominant PPAOS (AUROC 0.79). Five patients showed abnormal DAT uptake. Braak neurofibrillary tangle stage differed across groups (p = 0.01).

CONCLUSIONS

Patients with PPAOS and a right-dominant pattern of hypometabolism on FDG-PET have the fastest rates of decline of behavioral and motor features.

Neuroanatomical regions associated with non-progressive dysarthria post-stroke: a systematic review

Background

Dysarthria is a common and persisting sequela to stroke. It can have a negative influence on psychological wellbeing, and quality of life. This systematic review aimed to describe and identify the neuroanatomical regions associated with non-progressive dysarthria following stroke.

Methods

A systematic search of PubMed, Ovid Medline, CINAHL, Cochrane, Scopus, and ScienceDirect was conducted to identify all relevant articles published in peer-reviewed journals up to December 2021. Following data extraction, the National Institutes of Health (NIH) quality assessment tools were used to evaluate the methodological quality of the included studies.

Results

Out of 2186 papers found in the literature related to dysarthria post-stroke, 24 met the inclusion criteria. Eligible articles assessed 1150 post-stroke subjects. Out of them, 420 subjects had dysarthria from isolated lesions. Regarding dysarthric subjects with ischemic strokes, 153 sustained supratentorial infarctions, while 267 had infratentorial infarctions. The majority had pontine infarctions (n = 142), followed by infarctions in the corona radiata (n = 104), and the cerebellum (n = 64).

Conclusion

This systematic review is the first step toward establishing a neuroanatomical model of dysarthria throughout the whole brain. Our findings have many implications for clinical practice and provide a framework for implementing guidelines for early detection and management of dysarthria post-stroke.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02877-x.

Symptoms and probabilistic anatomical mapping of lacunar infarcts

Background

The anatomical distribution of acute lacunar infarcts has mainly been studied for supratentorial lesions. In addition, little is known about the association with distinct stroke symptoms, not summarized as classical lacunar syndromes. We aimed to describe the spatial lesion distribution of acute supra- and infratentorial lacunar infarcts and their association with stroke symptoms in patients eligible for thrombolysis.

Methods

All patients enrolled in the WAKE-UP trial (efficacy and safety of magnetic resonance imaging [MRI]-based thrombolysis in wake-up stroke) were screened for lacunar infarcts on diffusion-weighted imaging (DWI). The relationship between the anatomical distribution of supra- and infratentorial lacunar infarcts, their demographic characteristics and acute stroke symptoms, defined by the National Institutes of Health Stroke Scale (NIHSS) score, were correlated and compared.

Results

Maps of lesion distribution from 224 lacunar infarct patients (76 [33.9%] females, mean age [standard deviation] of 63.4 [11.5] years) were generated using computational image mapping methods. Median infarct volume was 0.73 ml (interquartile range [IQR] 0.37–1.15 ml). Median NIHSS sum score on hospital arrival was 4 (IQR 3–6). 165 (73.7%) patients had lacunar infarcts in the supratentorial deep white or grey matter, while 59 (26.3%) patients had infratentorial lacunar infarcts. Patients with supratentorial lacunar infarcts presented with a significantly lower occurrence of deficits in the NIHSS items gaze (p < 0.001) and dysarthria (p = 0.008), but had more often a paresis of the left arm (p = 0.009) and left leg (p = 0.068) compared to patients with infratentorial infarcts.

Conclusions

The anatomical lesion distribution of lacunar infarcts reveals a distinct pattern and supports an association of localization with different stroke symptoms.

Trial registration

NCT01525290.

A Systematic Review of Measures of Dysarthria Severity in Stroke Patients

OBJECTIVE

To define methods to measure dysarthria due to stroke and guide physicians in delineating a diagnostic protocol using the best current strategies.

DESIGN

Systematic review.

LITERATURE SURVEY

A search was conducted on PubMed, EMBASE, the Cochrane Library, and Web of Science to identify measurement methods for dysarthria severity in adults after stroke.

METHODS

Two reviewers independently reviewed articles and came to a consensus about which ones to include. The authors excluded all duplicates, articles involving individuals with aphasia or other speech problems other than dysarthria, and articles unrelated to stroke. Articles were included if diagnostic measures were used to examine the effectiveness of speech rehabilitation in stroke patients.

SYNTHESIS

The search identified 1154 articles with the keywords "stroke" OR "ictus" OR "cerebral vascular accident" AND "dysarthria" OR "Speech and Language Disorders" AND "diagnosis" OR "assessment." The reviewers analyzed 86 full texts. There were 37 publications that met the criteria and were included in the systematic review. These articles were used to describe the main methods used for measuring the severity of stroke-related dysarthria before and after speech rehabilitation.

CONCLUSION

Despite the range of diagnostic tools available, robust trials are lacking, and the diagnostic approaches are always different. More research is needed to find the best diagnostic methodologies and delineate a definitive diagnostic protocol.

A Case of Isolated Dysarthria in a COVID-19 Infected Stroke Patient: A Nondisabling Neurological Symptom With Grave Prognosis

Isolated dysarthria is a speech abnormality characterized by slurring without any language dysfunction, or other neurological deficits. In an acute setting, it is commonly associated with stroke. In the context of social distancing during the current corona virus disease 2019 (COVID-19) pandemic, nondisabling symptoms such as isolated dysarthria can delay a patient's perception to seek immediate medical care. We present a rare case of isolated dysarthria in a COVID-19 infected stroke patient with a grave prognosis. A 79-year-old African American male presented with isolated dysarthria that manifested two days prior to his hospital visit. The dysarthria assessment showed impaired articulation, phonation, and prosody. Other neurological examinations were normal. He tested positive for the COVID-19 infection. His pulmonary CT scan showed bilateral ground glass opacities. An electrocardiogram showed atrial fibrillation (AF). Brain MRI revealed a punctate acute infarction in the left frontal lobe. Initially, he was treated with IV anticoagulation, oral beta-blocker, azithromycin and hydroxychloroquine, but he dramatically deteriorated within a week exhibiting a highly elevated cytokine level eventually resulting in multi-system organ failure. Despite aggressive treatment with steroids, tocilizumab and other supportive measures, the patient died of cardiac arrest. Our case highlights that acute stroke could manifest as an isolated dysarthria, which is an indicator of increased severity and high mortality with COVID-19 infection. Public awareness about the stroke symptom awareness should be emphasized.

Dysarthria and stroke. The effectiveness of speech rehabilitation. A systematic review and meta-analysis of the studies

INTRODUCTION

Speech difficulties, such as dysarthria or aphasia, in addition to motor impairments are frequently seen in post-stroke patients.

EVIDENCE ACQUISITION

Literature searches with the keywords: "stroke" and "dysarthria" and "diagnosis" and "stroke" and "dysarthria" and "assessment" were conducted using PubMed, EMBASE, Cochrane Library, and Web of Science databases to perform the systematic review about the methods used to measure the severity of dysarthria in subjects post-stroke. The search was performed by two authors from 15 January to 22 February 2020. The research identified a total of 402 articles for the search using the keywords "stroke" and "dysarthria," and "diagnosis" and 84 references for the search using the keywords "stroke" and "dysarthria" and "assessment." Sixty-nine selected articles were analyzed by the reviewers. Thirty-seven publications met the inclusion criteria and were included in the systematic review. Thirty-two articles were excluded for several reasons: 1) 12 involved individuals with aphasia or other speech problems different from dysarthria; 2) 12 examined different topics from our aim; and 3) eight did not include post-stroke cases.

EVIDENCE SYNTHESIS

The systematic review identified methods for measuring the severity of post-stroke dysarthria. The meta-analysis showed the acoustic parameters affected in dysarthria secondary to stroke and the differences in these parameters after speech therapy.

CONCLUSIONS

The alternating and sequential motion rate (AMR- Pə, AMR-Tə, AMR-Kə, and SMR-PəTəKə) and maximum phonation time were significantly improved after speech rehabilitation.

Prevalence of aphasia after stroke in a hospital population in southern Brazil: a retrospective cohort study

Background: Aphasia negatively impacts quality of life. This is the first Brazilian study that investigates the prevalence of aphasia and its related factors, the results of which may underpin hospital and health service planning for this vulnerable population.Objective: To establish the prevalence of aphasia in patients after first-ever ischemic stroke (FEIS) and associated factors.Methods: This is a retrospective cohort study, based on a database held in Joinville, Brazil. All cases of FEIS admitted to one public hospital in Joinville in 2015 were selected. The diagnosis of aphasia was verified by neurologists through the language item of the National Institute of Health Stroke Scale (NIHSS).Results: Of the 350 patients with FEIS, 79 (22.6%) had aphasia. Patients with aphasia (PWA) were older, with a higher likelihood of dysarthria, more thrombolytic use, and greater stroke severity. PWA had higher mortality than patients without aphasia (24.1% versus 10.7%, p = .004) and longer hospitalization time (21.32 versus 17.46 days, p = .009). Higher NIHSS score was an independent predictor for the occurrence of aphasia on admission (OR 1.24, 95% CI 1.17-1.31, p < .001). Older age (OR 1.06, 95% CI 1.03-1.09, p < .001) and stroke severity by NIHSS (OR 1.19, 95% CI 1.12-1.25, p = <0.001) were independent predictors of death.Conclusions: PWA may need more health care during hospitalization, because of the severity of the stroke, and their frailty. Further studies are needed to assess the direct impact of aphasia on inpatients.

Acoustic properties of vowel production in Mandarin-speaking patients with post-stroke dysarthria

This study investigated the acoustic features of vowel production in Mandarin-speaking patients with post-stroke dysarthria (PSD). The subjects included 31 native Mandarin-speaking patients with PSD (age: 25–83 years old) and 38 neurologically normal adults in a similar age range (age: 21–76 years old). Each subject was recorded producing a list of Mandarin monosyllables that included six monophthong vowels (i.e., /a, i, u, ɤ, y, o/) embedded in the /CV/ context. The patients’ speech samples were evaluated by two native Mandarin speakers. The evaluation scores were then used to classify all patients into two levels of severity: mild or moderate-to-severe. Formants (F1 and F2) were extracted from each vowel token. Results showed that all vowel categories in the patients with PSD were produced with more variability than in the healthy speakers. Great overlaps between vowel categories and reduced vowel space were observed in the patients. The magnitude of the vowel dispersion and overlap between vowel categories increased as a function of the severity of the disorder. The deviations of the vowel acoustic features in the patients in comparison to the healthy speakers may provide guidance for clinical rehabilitation to improve the speech intelligibility of patients with PSD.

The pulvinar nucleus is associated with the presence of dysarthria in patients with basal ganglia hemorrhage

Dysarthria is a frequent symptom in patients with stroke. The anatomical structures responsible for dysarthria have been reported in patients with lacunar infarcts, but the related lesions in patients with basal ganglia hemorrhage (BGH) have not been investigated. The aim of this study was to identify associations between the lesion location and the presence/absence of dysarthria in patients with BGH using voxel-based lesion symptom mapping (VLSM) analyses. A retrospective analysis was conducted on 26 patients with acute BGH (mean age, 54.0 years; men:women, 14:12) who underwent conservative management. The patients were classified into groups based on the presence or absence of dysarthria at the time of admission, which was determined by reviewing the patients' medical records. Brain lesions were traced on magnetic resonance images that were acquired within the first 3 weeks after BGH onset, and then separate high-resolution region-of-interest images were generated. Associations between dysarthria and the lesion location were determined with the VLSM analyses. The average volume of the delimited lesions was 7.38±5.75cm³. The VLSM analyses identified several voxel clusters, mainly in the pulvinar nucleus of the left thalamus, that were significantly related to the presence of dysarthria at admission. These findings suggest that patients with BGH extending into the left pulvinar nucleus should be monitored for dysarthria.

Localization of orofacial representation in the corona radiata, internal capsule and cerebral peduncle in Macaca mulatta

Subcortical white matter injury is often accompanied by orofacial motor dysfunction, but little is known about the structural substrates accounting for these common neurological deficits. We studied the trajectory of the corticobulbar projection from the orofacial region of the primary (M1), ventrolateral (LPMCv), supplementary (M2), rostral cingulate (M3) and caudal cingulate (M4) motor regions through the corona radiata (CR), internal capsule (IC) and crus cerebri of the cerebral peduncle (ccCP). In the CR each pathway was segregated. Medial motor area fibers (M2/M3/M4) arched over the caudate and lateral motor area fibers (M1/LPMCv) curved over the putamen. At superior IC levels, the pathways were widespread, involving the anterior limb, genu and posterior limb with the M3 projection located anteriorly, followed posteriorly by projections from M2, LPMCv, M4 and M1, respectively. Inferiorly, all pathways maintained this orientation but shifted posteriorly, with adjacent fiber bundles overlapping minimally. In the ccCP, M3 fibers were located medially and M1 fibers centromedially, with M2, LPMCv, and M4 pathways overlapping in between. Finally, at inferior ccCP levels, all pathways overlapped. Following CR and superior IC lesions, the dispersed pathway distribution may correlate with acute orofacial dysfunction with spared pathways contributing to orofacial motor recovery. In contrast, the gradually commixed nature of pathway representation inferiorly may enhance fiber vulnerability and correlate with severe, prolonged deficits following lower subcortical and midbrain injury. Additionally, in humans these findings may assist in interpreting orofacial movements evoked during deep brain stimulation, and neuroimaging tractography efforts to localize descending orofacial motor pathways.

Effects of lingual strength training on lingual strength and articulator function in stroke patients with dysarthria

[Purpose] This study investigated the effects of lingual strength training (LST) on lingual strength and articulator function in stroke patients with dysarthria. [Subjects and Methods] 16 stroke patients with dysarthria were randomly assigned into two groups: the experimental group (n=8) or the control group (n=8). Both groups received the conventional rehabilitation therapy at 30 min/day, 5 times for week, and during 4 weeks, and the experimental group received an additional 30 min of LST using the Iowa Oral Performance Instrument (IOPI). The Maximum Isometric Tongue Pressures (MIPs) was used to assess the lingual strength and the Alternating-Motion Rate (AMR) and Sequential-Motion Rate (SMR) were used to measure the articulator function. [Results] After the intervention, the experimental group showed a significant improvement in MIPs and AMR (/tə/) than the control group. [Conclusion] Findings of this study suggest that LST provides positive effects on lingual strength and articulator function, and thus can be used as an interventional method in stroke patients with dysarthria.

MRI-Based Neuroanatomical Predictors of Dysphagia, Dysarthria, and Aphasia in Patients with First Acute Ischemic Stroke

Background

Due to the high post-stroke frequency of dysphagia, dysarthria, and aphasia, we developed comprehensive neuroanatomical, clinical, and demographic models to predict their presence after acute ischemic stroke.

Methods

The sample included 160 randomly selected first-ever stroke patients with confirmed infarction on magnetic resonance imaging from 1 tertiary stroke center. We documented acute lesions within 12 neuroanatomical regions and their associated volumes. Further, we identified concomitant chronic brain disease, including atrophy, white matter hyperintensities, and covert strokes. We developed predictive models using logistic regression with odds ratios (OR) and their 95% confidence intervals (95% CI) including demographic, clinical, and acute and chronic neuroanatomical factors.

Results

Predictors of dysphagia included medullary (OR 6.2, 95% CI 1.5–25.8), insular (OR 4.8, 95% CI 2.0–11.8), and pontine (OR 3.6, 95% CI 1.2–10.1) lesions, followed by brain atrophy (OR 3.0, 95% CI 1.04–8.6), internal capsular lesions (OR 2.9, 95% CI 1.2–6.6), and increasing age (OR 1.4, 95% CI 1.1–1.8). Predictors of dysarthria included pontine (OR 7.8, 95% CI 2.7–22.9), insular (OR 4.5, 95% CI 1.8–11.4), and internal capsular (OR 3.6, 95% CI 1.6–7.9) lesions. Predictors of aphasia included left hemisphere insular (OR 34.4, 95% CI 4.2–283.4), thalamic (OR 6.2, 95% CI 1.6–24.4), and cortical middle cerebral artery (OR 4.7, 95% CI 1.5–14.2) lesions.

Conclusion

Predicting outcomes following acute stroke is important for treatment decisions. Determining the risk of major post-stroke impairments requires consideration of factors beyond lesion localization. Accordingly, we demonstrated interactions between localized and global brain function for dysphagia and elucidated common lesion locations across 3 debilitating impairments.

Anatomy and lateralization of the human corticobulbar tracts: an fMRI-guided tractography study

The left hemisphere lateralization bias for language functions, such as syntactic processing and semantic retrieval, is well known. Although several theories and clinical data indicate a link between speech motor execution and language, the functional and structural brain lateralization for these functions has never been examined concomitantly in the same individuals. Here, we used functional MRI during rapid silent syllable repetition (/lalala/, /papapa/ and /pataka/, known as oral diadochokinesis or DDK) to map the cortical representation of the articulators in 17 healthy adults. In these same participants, functional lateralization for language production was assessed using the well-established verb generation task. We then used DDK-related fMRI activation clusters to guide tractography of the corticobulbar tract from diffusion-weighted MRI. Functional MRI revealed a wide inter-individual variability of hemispheric asymmetry patterns (left and right dominant, as well as bilateral) for DDK in the motor cortex, despite predominantly left hemisphere dominance for language-related activity in Broca's area. Tractography revealed no evidence for structural asymmetry (based on fractional anisotropy) within the corticobulbar tract. To our knowledge, this study is the first to reveal that motor brain activation for syllable repetition is unrelated to functional asymmetry for language production in adult humans. In addition, we found no evidence that the human corticobulbar tract is an asymmetric white matter pathway. We suggest that the predominance of dysarthria following left hemisphere infarct is probably a consequence of disrupted feedback or input from left hemisphere language and speech planning regions, rather than structural asymmetry of the corticobulbar tract itself.

Acute isolated dysarthria is associated with a high risk of stroke

Background

Isolated dysarthria is an uncommon presentation of transient ischemic attack (TIA)/minor stroke and has a broad differential diagnosis. There is little information in the literature about how often this presentation is confirmed to be a TIA/stroke, and therefore there is debate about the risk of subsequent vascular events. Given the uncertain prognosis, it is unclear how to best manage patients presenting to the emergency department (ED) with isolated dysarthria. The objective of this study was to prospectively identify and follow a cohort of patients presenting to EDs with isolated dysarthria in order to explore their natural history and risk of recurrent cerebrovascular events. Specifically, we sought to determine early outcomes of individuals with this nonspecific and atypical presentation in order to appropriately expedite their management.

Methods

Patients with isolated dysarthria having presented to 8 Canadian EDs between October 2006 and April 2009 were analyzed as part of a prospective multicenter cohort study of patients with acute neurological symptoms as assessed by emergency physicians. The study inclusion criteria were age ≥18 years, a normal level of consciousness, and a symptom onset <1 week prior to presentation without an established nonvascular etiology. The primary outcome was a subsequent stroke within 90 days of the index visit. The secondary outcomes were the rate of TIA, myocardial infarction, and death. Isolated dysarthria was defined as slurring with imprecise articulation but without evidence of language dysfunction. The overall rate of stroke in this cohort was compared with that predicted by the median ABCD2 score for this group.

Results

Between 2006 and 2009, 1,528 patients were enrolled and had a 90-day follow-up. Of these, 43 patients presented with isolated acute-onset dysarthria (2.8%). Recurrent stroke occurred in 6/43 (14.0%) within 90 days of enrollment. The predicted maximal 90-day stroke rate was 9.8% (based on a median ABCD2 score of 5 for the isolated dysarthria cohort). After adjusting for covariates, isolated dysarthria independently predicted stroke within 90 days (aOR: 3.96; 95% CI: 1.3-11.9; p = 0.014).

Conclusions

The isolated dysarthria cohort carried a recurrent stroke risk comparable to that predicted by the median ABCD2 scores. Although isolated dysarthria is a nonspecific and uncommon clinical presentation of TIA, these findings support the need to view it first and foremost as a vascular presentation until proven otherwise and to manage such patients as if they were at high risk of stroke in accordance with established high-risk TIA guidelines.

Speech motor deficits in cerebellar infarctions

Functional imaging studies demonstrated cerebellar activation during speech movements in the rostral cerebellar region. Ischemic lesions of this area, which is supplied by the superior cerebellar artery, induce dysarthria.

Isolated shoulder palsy due to cortical infarction: a case report and literature review of clinicoradiological correlations

Clinicoradiological correlations observed in patients with small cortical infarctions have supported somatotopic representation of different parts of body areas in primary motor cortex. However, isolated shoulder weakness because of infarction in precentral gyrus has rarely been described. We report an 80-year-old woman with isolated shoulder palsy because of cortical ischemic infarction in the base of the left precentral gyrus as confirmed by brain magnetic resonance imaging. In our patient, cardiogenic embolism or Trousseau syndrome associated with lung cancer was considered the cause of ischemic infarction. Physicians should consider small cortical infarction, when a patient complains of sudden onset of shoulder weakness without pain. In line with the previous reports, a responsible cortical lesion in our patient corresponded to motor shoulder area in the motor homunculus reported to be located more medially to the hand area.

The incidence, co-occurrence, and predictors of dysphagia, dysarthria, and aphasia after first-ever acute ischemic stroke

Dysphagia, dysarthria and aphasia occur frequently following stroke. Our purpose was to identify the incidence, co-occurrence, and predictors of these impairments after first-ever ischemic stroke. We used the Registry of the Canadian Stroke Network's database (2003-2008) from one stroke center to identify a random sample of 250 patients with acute ischemic stroke confirmed by MR imaging. We further conducted a retrospective medical chart review. We established reliable data capture and identified the presence of the three impairments. We derived incidence and co-occurrence estimates along with 95% confidence intervals (CI) for dysphagia, dysarthria, and aphasia. We then computed odds ratios (OR) through logistic regression to identify predictors. Twenty-nine patient charts were not available for review. Estimates of the incidence of dysphagia, dysarthria, and aphasia were 44% (95% CI, 38-51), 42% (95% CI, 35-48) and 30% (95% CI, 25-37), respectively. The highest co-occurrence of any two impairments was 28% (95% CI, 23-34) for the presence of both dysphagia and dysarthria. Ten percent of all 221 patients had all three impairments. The highest predictors were non-alert level of consciousness for dysphagia (OR 2.6, CI 1.03-6.5), symptoms of weakness for dysarthria (OR 5.3, CI 2.4-12.0), and right-sided symptoms for aphasia (OR 7.1, CI 3.1-16.6). These findings are a first step toward identifying the incidence and predictors of multiple co-occurring impairments in a homogenous stroke sample.

LEARNING OUTCOMES

Learning outcomes: Readers will be able to (1) RECOGNIZE the need for research in stroke, whereby outcomes are reported according to stroke etiology and recurrence patterns, (2) identify the incidence and co-occurrence of dysphagia, dysarthria, and aphasia after a first-ever acute ischemic stroke, and (3) describe clinical precursors of these impairments in the acute stage of stroke.

Lesions to the posterior insular cortex cause dysarthria

BACKGROUND

Up to now, there are few systematic studies in a sufficient number of patients with lesions involving the insular cortex (IC) examining whether damage of the IC is directly related to dysarthria. Thus, this is the first study applying modern voxel-lesion behaviour mapping (VLBM) aimed to examine whether the IC is involved in dysarthria - and if so - which part of the IC is involved.

METHODS

Twenty-five patients with acute stroke lesions affecting the IC and peri-insular region were investigated employing VLBM analysis.

RESULTS

Present data indicated that dysarthria is associated with stroke lesions affecting the right- and left-sided posterior IC.

CONCLUSIONS

Owing to the known extensive spectrum of cortical and subcortical somatosensory and motor connections, it seems that the IC might be one region involved in the generation of speech motor execution.

[Cerebellar infarction]

Cerebellar infarction can be difficult to diagnose because the clinical picture is often dominated by fairly non-specific symptoms, which are more indicative of a benign condition. When cerebellar infarction affects the brainstem, the semiology is richer, and pure cerebellar signs are rendered less important. A perfect knowledge of the organisation of the cerebellar artery territories is required, regardless of the infarct topography. This knowledge is essential for making an accurate diagnosis, understanding the mechanisms and organising a treatment plan. Clinical algorithms for the treatment of dizziness, headaches and vomiting would improve the selection of candidates for brain imaging. Thus, the early identification of patients with a high risk of subsequent deterioration would lead to a better prognosis in cases of cerebellar artery territory infarction.

Role of cerebellum in fine speech control in childhood: persistent dysarthria after surgical treatment for posterior fossa tumour

Dysarthria following surgical resection of childhood posterior fossa tumour (PFT) is most commonly documented in a select group of participants with mutism in the acute recovery phase, thus limiting knowledge of post-operative prognosis for this population of children as a whole. Here we report on the speech characteristics of 13 cases seen long-term after surgical treatment for childhood PFT, unselected for the presence of post-operative mutism (mean time post-surgery=6y10m, range 1;4-12;6 years, two had post-operative mutism), and examine factors affecting outcome. Twenty-six age- and sex- matched healthy controls were recruited for comparison. Participants in both groups had speech assessments using detailed perceptual and acoustic methods. Over two-thirds of the group (69%) with removal of PFT had a profile of typically mild dysarthria. Prominent speech deficits included consonant imprecision, reduced rate, monopitch and monoloudness. We conclude that speech deficits may persist even up to 10 years post-surgery in participants who have not shown mutism in the acute phase. Of cases with unilateral lesions, poorer outcomes were associated with right cerebellar tumours compared to left, consistent with the notion based on adult data that speech is controlled by reciprocal right cerebellar/left frontal interactions. These results confirm the important role of the cerebellum in the control of fine speech movements in children.

Dysarthria in stroke: a narrative review of its description and the outcome of intervention

Dysarthria is a frequent and persisting sequel to stroke and arises from varied lesion locations. Although the presence of dysarthria is well documented, for stroke there are scant data on presentation and intervention outcome. A literature search was undertaken to evaluate (a) the features of dysarthria in adult stroke populations relative to the conventional Mayo system for classification, which was developed from diverse pathological groups, and (b) the current status of evidence for the effectiveness of intervention in dysarthria caused by stroke. A narrative review of results is presented. The limited data available indicate that, regardless of stroke location, imprecise articulation and slow speaking rate are consistent features, and voice disturbances, especially harshness, and reduced prosodic variation are also common. Dysarthria is more prevalent in left than in right hemisphere lesions. There is a need for comprehensive, thorough analysis of dysarthria features, involving larger populations, with stroke and other variables controlled and with appropriate age-referenced control data. There is low level evidence for benefits arising from intervention in stroke-related dysarthria. Because studies involve few participants, without external control, and sometimes include stroke with other aetiologies, their results lack the required weight for confident evidence-based practice.

Clinical manifestations of cerebellar infarction according to specific lobular involvement

Lesions in the cerebellum produce various symptoms related to balance and motor coordination. However, the relationship between the exact topographical localization of a lesion and the resulting symptoms is not well understood in humans. In this study, we analyzed 66 consecutive patients with isolated cerebellar infarctions demonstrated on diffusion-weighted magnetic resonance imaging. We identified the involved lobules in these patients using a cross-referencing tool of the picture archiving and communication system, and we investigated the relationships between the sites of the lesions and specific symptoms using χ (2) tests and logistic regression analysis. The most common symptoms in patients with isolated cerebellar infarctions were vertigo (87%) and lateropulsion (82%). Isolated vertigo or lateropulsion without any other symptoms was present in 38% of patients. On the other hand, limb ataxia was a presenting symptom in only 40% of the patients. Lateropulsion, vertigo, and nystagmus were more common in patients with a lesion in the caudal vermis. Logistic regression analysis showed that lesions in the posterior paravermis or nodulus were independently associated with lateropulsion. Lesions in the nodulus were associated with contralateral pulsion, and involvement of the culmen was associated with ipsilateral pulsion and isolated lateropulsion without vertigo. Nystagmus was associated with lesions in the pyramis lobule, while lesions of the anterior paravermis were associated with dysarthria and limb ataxia. Our results showed that the cerebellar lobules are responsible for producing specific symptoms in cerebellar stroke patients.

Paroxysmal dysarthria and ataxia in multiple sclerosis and corresponding magnetic resonance imaging findings

Paroxysmal dysarthria (PD) and paroxysmal dysarthria-ataxia (PDA) syndromes are uncommon symptoms of the neurological dysfunction in multiple sclerosis (MS). We describe two patients who had clinically definite MS presented with symptomatic PD and PDA syndromes, respectively, related to demyelinating lesions. In one patient, the PD symptom was the initial manifestation of an acute episode. In the other patient, the episode of dysarthria was accompanied by ataxia disorders. Both patients had midbrain lesions at or below the level of the right red nucleus on magnetic resonance imaging (MRI), confirming that this area is critically involved. Both responded well to carbamazepine (CBZ).

Speech and oral motor profile after childhood hemispherectomy

Hemispherectomy (disconnection or removal of an entire cerebral hemisphere) is a rare surgical procedure used for the relief of drug-resistant epilepsy in children. After hemispherectomy, contralateral hemiplegia persists whereas gross expressive and receptive language functions can be remarkably spared. Motor speech deficits have rarely been examined systematically, thus limiting the accuracy of postoperative prognosis. We describe the speech profiles of hemispherectomized participants characterizing their intelligibility, articulation, phonological speech errors, dysarthric features, and execution and sequencing of orofacial speech and non-speech movements. Thirteen participants who had undergone hemispherectomy (six left, seven right; nine with congenital, four with acquired hemiplegia; operated between four months and 13 years) were investigated. Results showed that all participants were intelligible but showed a mild dysarthric profile characterized by neuromuscular asymmetry and reduced quality and coordination of movements, features that are characteristic of adult-onset unilateral upper motor neuron dysarthria, flaccid-ataxic variant. In addition, one left and four right hemispherectomy cases presented with impaired production of speech and non-speech sequences. No participant showed evidence of verbal or oral dyspraxia. It is concluded that mild dysarthria is persistent after left or right hemispherectomy, irrespective of age at onset of hemiplegia. These results indicate incomplete functional re-organization for the control of fine speech motor movements throughout childhood, and provide no evidence of hemispheric differences.

MRI detection of the cerebellar syndrome in Creutzfeldt-Jakob disease

Creutzfeldt-Jakob Disease (CJD) is characterized by bilateral basal ganglia hyperintensities on T2W and diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) scans, consistent with its extrapyramidal neurological manifestations. MRI is diagnostically uninformative about the cerebellar symptoms, equally prominent in CJD. This study was undertaken to explain this apparent paradox. Eleven CJD patients with definite cerebellar or brain stem symptoms were selected from a large prospective study, as well as 11 healthy controls matched for age and gender. All subjects participated in a standardized MRI protocol, including SPGR, fluid-attenuated inversion recovery (FLAIR), DWI and diffusion tensor imaging (DTI). All subjects underwent detailed examination by a neurologist blinded to the radiological findings, who predicted the expected site of cerebral abnormalities. MRI showed good sensitivity for the abnormalities predicted in the cortex (80-90%) and basal ganglia (100%). None of the standard MRI sequences, including DWI, DTI, and FLAIR, revealed any tissue abnormalities in cerebellum or brain stem. Apparent diffusion coefficient (ADC) values, however, were substantially and significantly elevated in several cerebellar structures, where also the volumetric (VBM) analysis revealed elevated cerebrospinal fluid volume, suggesting focal cerebellar atrophy in these CJD patients. In patients with CJD, DWI appears sensitive to the reduced diffusivity in cortex and basal ganglia but insensitive to cerebellar involvement. We propose that the radiological hallmark of cerebellar pathology in CJD is atrophy, revealed quantitatively by both VBM and elevated diffusivity, which is identifiable on ADC maps but poorly visualized in nonquantitative DWI images.

Ischemic stroke of the cortical "hand knob" area: stroke mechanisms and prognosis

Cortical ischemic stroke affecting the precentral "hand knob" area is a rare but well known stroke entity. To date, little is known about the underlying stroke mechanisms and the prognosis. Twenty-nine patients admitted to our service between 2003 and 2007 were included in the study on the basis of an acute ischemic infarct of the cortical "hand knob" area confirmed by diffusion-weighted magnetic resonance imaging with contralateral hand paresis. For all patients clinical, epidemiological as well as imaging data at the time point of admission were analysed retrospectively and follow-up data on all patients was obtained. The majority (n = 21/72%) had an isolated infarct of the cortical "hand knob" area. In 23 (79%) patients it was a first ever stroke. Ten patients (34%) had ipsilateral extracranial stenosis of the internal carotid artery (ICA), whereas potential cardiac embolic sources were less frequent (n = 4/14%). No patient exhibited ipsilateral MCA stenosis. All but two patients (93%) had marked atherosclerotic alterations of the ICA. Hypertension was the most prevalent vascular risk factor (n = 23/79%). At follow-up (mean 25.0 months, range 0.4-47.4 months) no patient had died and only one (3%) experienced a recurrent stroke. The majority of patients (79%) reported improvement of hand paresis, 17 (59%) were asymptomatic (modified Rankin score = 0). Only one patient was significantly disabled due to a recurrent stroke. In conclusion, ischemic infarcts affecting the cortical "hand knob" area are frequently associated with atherosclerotic changes of the carotid artery, suggesting an arterio-arterial thrombembolic stroke mechanism. It mostly reflects first ever ischemic stroke, and follow-up data suggest a rather benign course.

Isolated facio-lingual hypoalgesia and weakness after a hemorrhagic infarct localized at the contralateral operculum

Isolated facio-lingual hypoesthesia and weakness is rare. We describe a case of isolated facio-lingual hypoesthesia and weakness after a hemorrhagic infarct localized at the contralateral operculum. A 66-year-old woman developed acute onset of facio-lingual hypoalgesia, hypoesthesia, and weakness, with no such symptoms being observed in other parts of the body. Brain magnetic resonance imaging showed a subacute hemorrhagic infarct in the right frontal operculum, which spread slightly to the right temporo-parietal operculum. (123)IMP-SPECT showed hypoperfusion in the right fronto-temporo-parietal operculum, as detected by MRI, without apparent diaschisis within the brain. Neuroimaging findings for our patient suggested the involvement of the primary somatosensory-motor cortices (S1 and M1) and the secondary somatosensory cortex (S2), which receive trigemino-thalamo-cortical pathways.