Diffusion tensor imaging magnetic resonance imaging (DTI-MRI) helps to tailor speech therapy: A case report with a short narrative review

Abstract

BACKGROUND: Stroke has functional sequelae, including motor weakness, spasticity, dysphagia, and neurogenic bladder deteriorating activities of daily living. Speech therapy is more often an essential part of the rehabilitation program. Studies in aphasia have primarily focused on two major pathways: the arcuate fasciculus and the superior longitudinal fasciculus. The arcuate fasciculus is a major fiber bundle connecting Broca’s area (associated with language production) and Wernicke’s area (associated with language comprehension). Damage to this pathway can result in different types of aphasia, depending on the location and extent of the injury. CASE DESCRIPTION: Tractography is a neuroimaging technique used to map the white matter tracts in the brain. Our patient had an occlusion of the external carotid and left carotid siphon. The patient exhibited early complex language deficits involving both motor expressive and comprehensive abilities. After three months the patient presented conduction aphasia caused by damage to the inferior parietal lobule, which extends into the subcortical white matter and damages the arcuate fascicle. This patient was re-assessed for spasticity and language treatments needs, few months after the stroke. Considering first two months language improvement followed by any further language expressive improvement from 3rd to 6th month, a diffusion tensor imaging (DTI) tractography was requested to study interconnections between cortical and subcortical matter. The brain magnetic resonance imaging (MRI) performed in our hospital showed an extensive malacic gliotic area in the left temporal-frontal parietal site. CONCLUSION: Brain MRI is confirmed as a multimodal tool evaluating the damage, both from the point of structural and functional view. Tractography in aphasia allows focusing on major pathways. The involvement of the arcuate fascicle, whose lesion disconnects Broca’s and Wernicke’s areas, is related to clinical improvement, and represents a neural correlate of the brain injury recovery process that physicians and speech therapists might be aware of it, tailoring the plane of care of each patient.