Aphasia Induced by Infratentorial Ischemic Stroke: Two Case Reports

Abstract

Aphasia induced by an infratentorial stroke has rarely been reported, and its mechanism has not been fully identified. We evaluated two individuals who had been admitted to Saiseikai Kumamoto Hospital in Kumamoto, Japan, due to acute ischemic stroke in order to determine whether their aphasia was induced by an infratentorial stroke. The first patient, a 59-year-old man with a history of left parietal embolic stroke with very mild sequelae of anomia, developed Wernicke’s aphasia, nonfluent speech, and right limb ataxia as a result of the stroke. The second patient, a 76-year-old woman with a history of chronic renal failure, experienced transcortical sensory aphasia and right one-and-a-half syndrome as a result of the stroke. Both patients’ recent ischemic lesions were limited to the right cerebellar hemisphere and the right medial portion of the midbrain. However, SPECT showed low-uptake lesions in both patients’ left cerebral hemisphere that did not include the recent ischemic lesions but that had spread to an extent that was difficult to be explained by the old or recent ischemic lesions and that might be responsible for their recent aphasia. We believe that the aphasia experienced by these two patients may have been caused by crossed cerebello-cerebral diaschisis.

The Progress of Functional Magnetic Resonance Imaging in Patients with Poststroke Aphasia

“…Language information is introduced into Wernicke area and processed and transmitted to Broca area by arcuate fiber bundle. Finally, Broca area processes the information and transforms it into language activities [ 16 ]. Most scholars believe that speech disorders caused by lesions in different parts of the left cerebral hemisphere have their own characteristics, including Broca aphasia caused by damage to the Broca area in the posterior part of the left inferior frontal gyrus, Wernicke aphasia caused by damage to the Wernicke area in the posterior part of the temporal transverse gyrus of the auditory cortex, conductive aphasia caused by damage to the projection fibers or arcuate bundles between the temporal-parietal and frontal lobes, and complete aphasia caused by Broca area, Wernicke area, basal ganglia area, and insula damage [ 17 – 19 ].…”

Cerebellar compensation: a case of aphasia due to cerebellar hemorrhage

“…Inatomi et al reported a patient with infratentorial infarction who developed aphasia after recovering from a speech disturbance due to left parietal lobe infarction. They hypothesized that disruption of the compensatory intensi cation of the crossed cerebellocerebral pathway caused by the initial infarction may be associated with infratentorial stroke-induced aphasia [4]. However, detailed information about the symptoms of speech disturbance due to the initial infarction was not provided in the report.…”

Voxel-based analysis of the metabolic asymmetrical and network patterns in hypermetabolism-associated crossed cerebellar diaschisis

“…Crossed cerebellar diaschisis (CCD), firstly reported in cerebral infarction patients, was defined as coupled hypometabolism and hypoperfusion in the cerebellar hemisphere contralateral to the supratentorial lesions ( Baron et al, 1981 , Sebök et al, 2021 ). In addition to the ataxic hemiparesis, cerebellar dysfunction within CCD may be involved in the abnormal posture, shoulder subluxation, and impairment of non-motor functions as well ( Chang et al, 2017 , Hsieh et al, 2020 , Inatomi et al, 2021 , Kwon et al, 2015 , Nishida et al, 2019 , Yoshida et al, 2018 ). Consequently, more extensive investigations are required for the better intervention of CCD and its associated comorbidities.…”