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

Longitudinal flortaucipir, metabolism and volume differ between phonetic and prosodic speech apraxia

Progressive apraxia of speech (PAOS) is a neurodegenerative motor-speech disorder that most commonly arises from a four-repeat tauopathy. Recent studies have established that progressive apraxia of speech is not a homogenous disease but rather there are distinct subtypes: the phonetic subtype is characterized by distorted sound substitutions, the prosodic subtype by slow and segmented speech and the mixed subtype by a combination of both but lack of predominance of either. There is some evidence that cross-sectional patterns of neurodegeneration differ across subtypes, although it is unknown whether longitudinal patterns of neurodegeneration differ. We examined longitudinal patterns of atrophy on MRI, hypometabolism on 18F-fluorodeoxyglucose-PET and tau uptake on flortaucipir-PET in a large cohort of subjects with PAOS that had been followed for many years. Ninety-one subjects with PAOS (51 phonetic, 40 prosodic) were recruited by the Neurodegenerative Research Group. Of these, 54 (27 phonetic, 27 prosodic) returned for annual follow-up, with up to seven longitudinal visits (total visits analysed = 217). Volumes, metabolism and flortaucipir uptake were measured for subcortical and cortical regions, for all scans. Bayesian hierarchical models were used to model longitudinal change across imaging modalities with PAOS subtypes being compared at baseline, 4 years from baseline, and in terms of rates of change. The phonetic group showed smaller volumes and worse metabolism in Broca's area and the striatum at baseline and after 4 years, and faster rates of change in these regions, compared with the prosodic group. There was also evidence of faster spread of hypometabolism and flortaucipir uptake into the temporal and parietal lobes in the phonetic group. In contrast, the prosodic group showed smaller cerebellar dentate, midbrain, substantia nigra and thalamus volumes at baseline and after 4 years, as well as faster rates of atrophy, than the phonetic group. Greater hypometabolism and flortaucipir uptake were also observed in the cerebellar dentate and substantia nigra in the prosodic group. Mixed findings were observed in the supplementary motor area and precentral cortex, with no clear differences observed across phonetic and prosodic groups. These findings support different patterns of disease spread in PAOS subtypes, with corticostriatal patterns in the phonetic subtype and brainstem and thalamic patterns in the prosodic subtype, providing insight into the pathophysiology and heterogeneity of PAOS.

The Radboud dysarthria assessment: validity and reliability of the Arabic version

PURPOSE

To cross-culturally adapt and validate the Radboud Dysarthria Assessment (RDA) and the speech component of the Radboud Oral Motor inventory for Parkinson's disease (ROMP-speech) into the Arabic language among Lebanese subjects with dysarthria.

MATERIALS AND METHODS

This study included 50 participants with dysarthria. The Arabic versions of the RDA (A-RDA) and the ROMP-speech (A-ROMP-speech) were administered in addition to the Arabic Speech Intelligibility test, the Lebanese Voice Handicap Index-10 (VHI-10lb) and semantic verbal fluency tasks. The maximum performance tasks were analyzed using the Praat software. The A-RDA qualitative recording form and the A-ROMP-speech were assessed for construct validity and internal consistency. The convergent validity of the maximum performance tasks, the severity scale, and the A-ROMP-speech were evaluated.

RESULTS

Exploratory factor analysis of the qualitative recording form extracted 3 factors explaining 82.973% of the total variance, and it demonstrated high internal consistency (α = 0.912). The maximum performance tasks of the RDA correlated significantly with the corresponding Praat scores. The severity scale and the A-ROMP-speech correlated fairly to strongly with the Arabic Speech Intelligibility test (rs=-0.695 and -0.736, p < 0.001) and the VHI-10lb (r = 0.539 and 0.640, p < 0.001).

CONCLUSION

The A-RDA and the A-ROMP-speech are valid and reliable dysarthria tools among Lebanese subjects.

A Stroke of Bad Luck: An Autobiographical Case Report

Strokes are a common cause of death. Cardiovascular disease, including atrial fibrillation and atrial flutter, is a frequent cause of ischemic strokes. A 64-year-old man developed isolated dysarthria without any other neurologic manifestations as the presentation of an ischemic stroke resulting from occlusion to the middle cerebral artery and affecting the cortex supplied by the artery. He was discovered to be in atrial flutter which was determined to be the likely etiology of his stroke. He was hospitalized and anticoagulated with heparin; as an outpatient, his anticoagulation was maintained with the direct oral anticoagulant apixaban. Amiodarone was required to medically convert him to normal sinus rhythm; he has typical atrial flutter and is going to be evaluated for atrial flutter ablation. His dysarthria began to improve within 24 hours after he experienced the stroke; after five weeks of speech therapy his ability to talk continues to progressively improve and the residual deficits in his speech continue to resolve. Anticoagulation is required for stroke prevention in individuals with atrial fibrillation and atrial flutter. Warfarin, a vitamin K antagonist, is usually used for individuals with valvular atrial fibrillation. Direct oral anticoagulants have fewer bleeding complications and are usually recommended for nonvalvular atrial fibrillation; they include the direct thrombin inhibitor dabigatran or a factor ten a (Xa) inhibitor such as either apixaban, edoxaban, or rivaroxaban. Dysarthria is a common manifestation in stroke patients. Albeit, it is less common, isolated dysarthria without any other neurologic sequellae may be associated with stroke. Interventions encouraged by speech pathologists to enhance the resolution of post-stroke dysarthria include speaking louder to amplify the voice and exaggerating the movements of the mouth when speaking.