Tongue Deviation in Acute Ischaemic Stroke: A Study of Supranuclear Twelfth Cranial Nerve Palsy in 300 Stroke Patients

Abstract

It is generally believed that the supranuclear innervation of the hypoglossal nucleus is bilateral and symmetrical. The aim of this work is to study the frequency and clinical characteristics of supranuclear tongue palsy in unilateral stroke. 300 patients with acute unilateral ischaemic motor strokes (excluding those in the lower brainstem) and an equal number of normal controls were studied for the presence of tongue deviation in a standardised manner. 29% of stroke patients and 5% of controls had tongue deviation (p < 0.00001). Deviation was always to the side of the limb weakness. In patients with a history of stroke, it occurred more frequently in those with previous stroke on the contralateral side. Tongue deviation was most common in patients with clinical features of the non-lacunar stroke subtype (56%) or in those with cortical or large subcortical infarctions on brain CT scan (55 and 45%, respectively). All tongue deviations were associated with supranuclear 7th nerve palsy. Dysphagia and dysarthria occurred in 43 and 90% of patients with tongue deviation. Weakness of the arm was significantly associated with presence of tongue deviation. Tongue deviation in unilateral stroke most likely results from asymmetrical supranuclear control of the 12th cranial nerve in many individuals. The finding that it occurs relatively commonly in large (non-lacunar) infarcts and its association with dysphagia may have clinical utility.

Dysarthria due to Supratentorial and Infratentorial Ischemic Stroke: A Diffusion-Weighted Imaging Study

“…Some of these lesions are relatively large and probably include subcortical motor fibers, which could have contributed to dysarthria. However, the lesions are predominantly cortical and distinguished from previously reported subcortical infarcts producing pure dysarthria [11, 12,32,33,34,35]. …”

Transient Hemiglossal Denervation during Acute Internal Capsule Infarct in the Setting of Dysarthria−Clumsy Hand Syndrome

“…11 Corticolingual tract fibers (also referred to as corticohypoglossal tract or corticonuclear tract) extend from the precentral gyri through the corona radiata, internal capsules, and cerebral peduncles to the pontomedullary junction where some fibers decussate. 6 Isolated dysarthria due to lacunar or cortical infarction is rare and is thought to be due to corticolingual tract dysfunction.…”

“…2 Commonly, supranuclear hypoglossal palsy is associated with ipsilesional arm weakness and supranuclear facial palsy, dysarthria, and dysphagia, presumably due to the close anatomic relationship of the respective motor pathways. 6,7 While the hypoglossal nerve is a lower motor neuron, crossed and uncrossed upper motor neuron corticolingual fibers extend from both hemispheres to the hypoglossal nuclei. 5 Following unilateral infarction, TMS of the affected hemisphere fails to produce an ipsilateral or contralateral lingual response, whereas TMS of the unaffected hemisphere produces a bilateral lingual response, even in the setting of unilateral lingual paralysis.…”

“…[2][3][4][5][6][7] We report a case of transient reversible hemiglossal denervation edema on MR imaging, contralateral to acute internal capsule infarction in the clinical setting of DCHS. A neuroanatomic basis is discussed.…”

Tongue-controlled robotic rehabilitation: A feasibility study in people with stroke

“…Furthermore, the tongue can move rapidly and accurately in almost every direction within the oral space, and it has the added benefit of fatigue-resistant muscle fibers [11], allowing for extended periods of use. Although speech and language are often affected by stroke [12], survivors generally maintain their voluntary tongue control [13], which makes the tongue a potential vehicle for controlling rehabilitation devices.…”