Transcortical mixed aphasia with left frontoparietal lesions

Aphasia associated with non-traumatic subarachnoid haemorrhage: a systematic review

PURPOSE

Individuals with non-traumatic subarachnoid haemorrhage (SAH) are often excluded from studies of stroke populations due to differing pathophysiology and treatment pathways. Thus, aphasia presentation in the non-traumatic SAH population is potentially under-represented within existing research evidence.

MATERIALS AND METHODS

Five databases were systematically searched with terms related to "aphasia" and "subarachnoid haemorrhage." Studies were included if aphasia was attributed to non-traumatic SAH or its associated complications, and where at least one language assessment measure used determined the presence or absence of aphasia. Study quality was evaluated using the Mixed Methods Appraisal Tool (MMAT).

RESULTS

Following deduplication, 2726 articles were identified for title and abstract screening. Full text screening for 162 articles occurred, with 18 articles selected for inclusion. Aphasia incidence ranged from 5 to 24%, and was influenced by assessment measure, timing of assessment, subgroup studied, and classifications of aphasia. Many studies excluded participants with poorer clinical outcome, intracerebral complications, or severe aphasia. Few studies used comprehensive language assessment measures to examine across language domains.

CONCLUSIONS

Aphasia presentation is highly heterogenous following non-traumatic SAH. Future research using comprehensive language assessments at multiple time points post onset is required to better understand aphasia presentation and management needs for this population.

Borderzone strokes and transcortical aphasia

Borderzone infarcts (BZIs) are anatomically defined as ischemic lesions occurring at the junction between two arterial territories, accounting for 2% to 10% of strokes. Three types of hemispheric BZIs are described according to topography (ie, superficial anterior, posterior, and deep). Although published series on related aphasia are rare in the setting of BZI, aphasia is of transcortical (TCA) type, characterized by the preservation of repetition. TCA can be of motor, sensory, or mixed type depending on whether expression, understanding, or both are impaired. Recent studies have reported specific aphasic patterns. BZI patients initially presented with mixed TCA. Aphasia specifically evolved according to the stroke location, toward motor or sensory TCA in patients with respectively anterior or posterior BZI. TCA was associated with good long-term prognosis. This specific aphasic pattern is interesting in clinical practice because it prompts the suspicion of a BZI before the MRI is done, and it helps in the planning of rehabilitation and in providing adapted information to the patient and family concerning the likelihood of language recovery.