External and Extreme Capsular Stroke: Clinical, Topographical and Etiological Patterns

Abstract

Background and Purpose: To characterize clinically acute external (EcC) and extreme capsular (ExC) strokes in 9 patients with first-ever acute stroke. Methods: Nine patients with a lesion limited to the EcC-ExC region proven by diffusion-weighted imaging included in our registry, corresponding to 0.3% of 3,600 patients with ischemic stroke, were studied. Results: We found three main groups of clinical manifestations: (1) motor deficits in all patients (4 with faciobrachial, 2 with faciobrachiocrural, and 1 with brachiocrural, crural and facial paresis each); (2) hypesthesia in 3 patients with partial distribution concerning light touching without involvement of other sensory modalities; (3) transient speech disturbance at stroke onset in 1 patient and dysarthria in 2 patients. Small artery disease in 4 patients and artery-to-artery embolism in 3 patients probably from atherosclerotic carotid artery were the main stroke mechanism. Conclusions: Strokes restricted to the EcC-ExC region may present with complete or partial motor syndromes and dysarthria as prominent clinical presentations, but also fou rire prodromique and transient speech arrest as prodromal signs. The main etiology of stroke were microangiopathy and artery-to-artery embolism, even though no obvious cause was found in 1 patient. The prognosis was good in almost all patients.

Insular Ischemic Stroke: Clinical Presentation and Outcome

“…These deficits are in line with known functions of the insula, based on previous electrophysiological, functional and lesional studies [1,20]. For example, Penfield and others [21,22,23,24] have consistently reported somatosensory-but also language-, speech-, vestibular- and motor-evoked responses during stimulation of the insular cortex.…”

Evidence for Cognitive Deficits in X-Linked Charcot-Marie-Tooth Disease

“…In patients with CMTX, Lee et al (2017) found additional abnormalities (indicated by decreased fractional anisotropy and/or increased radial diffusivity) in several white matter tracts, including the external capsule, the cingulate, the fornix, and the superior longitudinal fasciculus (SLF I). The external capsule is known to consist of fibers mainly supporting cortico-subcortical connections (Kumral & Çalli, 2006;Ribas, Yağmurlu, de Oliveira, Ribas, & Rhoton, 2018). Most importantly, it is often indistinguishable from the extreme capsule in studies utilizing standard neuroradiological evaluation (e.g.…”