Spectrum of medial medullary infarction: clinical and magnetic resonance imaging findings

WOS: 000173780500012PubMed ID: 11954873Among 4200 consecutive patients admitted to three hospitals with acute ischemic stroke, we found only 11 patients in whom magnetic resonance imaging (MRI) had proved that they had medial medullary infarction (MMI). In our centers, patients with MMI were less than 1% of those with vertebrobasilar stroke. The infarcts documented by MRI were unilateral in 10 patients and bilateral in one. On clinico-topo-graphical analysis there were four clinical patterns: (1) Classical Dejerine's syndrome was the most frequent, consisting of contralateral hemiparesis, lemniscal sensory loss and ipsilateral lingual palsy in 7 of the eleven patients. (2) Pure hemiparesis was present in 2 patients; (3) Sensorimotor stroke was present in 1 patient with contralateral hemiparesis, hypesthesia and mild decrease in pain sensation without lingual palsy; (4) Bilateral MMI syndrome in I patient, accompanied by tetraparesis, bilateral loss of deep sensation, dysphagia, dysphonia and anarthria. Presumed causes of MMI were intrinsic branch penetrator artery disease with concomitant vertebral artery stenosis in 6 of the 11 patients, vertebral artery occlusion in 2, dolichoectatic vertebrobasilar arteries in 2, a source of cardiac embolism in 1. Prognosis at 3 months was favorable in 8 patients, but the patient with bilateral MMI syndrome had persisting motor deficit causing limitation of daily activities, and 2 died from systemic causes. The classical triad of acute MMI facilitates the diagnosis, although the recognition of this syndrome in patients with incomplete manifestations can be difficult and occurs more frequently than commonly thought. Moreover, vertebral artery atherosclerosis and branch atheromatous disease of the penetrating arteries are the main causes of medullary infarction

Oropharyngeal swallowing in craniocervical dystonia

Objective: To clarify the pathophysiology of dysphagia by electrophysiological methods. Method: Electrophysiological methods related to oropharyngeal swallowing were used to investigate 25 patients with cervical dystonia and 25 age matched normal volunteers. Results: Dysphagia was suspected in 36% of patients with cervical dystonia on the basis of clinical assessment. The incidence of dysphagia increased to 72% on electrophysiological evaluation of pharyngeal swallowing. Submental muscle electromyographic (EMG) and laryngeal relocation times were significantly prolonged and the triggering time to swallowing reflex was significantly delayed. Some abnormalities seen in cricopharyngeal sphincter muscle EMG indicated that the striated sphincter muscle is hyperreflexive in some patients. Conclusion: Neurogenic dysphagia was more prominent and longer lasting than mechanical dysphagia, which was transient and varied from patient to patient. Although these electrophysiological methods were not suitable for detecting anatomical changes during swallowing, as in videofluoroscopic studies, observations supported the neurogenic cause of dysphagia in patients with any kind of cervical dystonia

Corticonuclear innervation to facial muscles in normal controls and in patients with central facial paresis

WOS: 000228501400007PubMed ID: 15726262Recently it has been proposed that corticobulbar innervation of the lower facial muscles is bilateral, that is from both right and left sides of the motor cortex. The objectives of this study were, i) to evaluate the corticonuclear descending fibers to the perioral muscles and, ii) to determine how central facial palsy (CFP) occurs and often recovers rapidly following a stroke. Eighteen healthy volunteers and 28 patients with a previous history of a stroke and CFP (mean ages: 51 and 61 years) were investigated by TMS (transcranial magnetic stimulation) with a figure of eight coil. Intracranial facial nerve and cortical motor evoked potentials (MEPs) were recorded from the perioral muscles. The periorbital MEPs were also studied. The absence of MEPs in both perioral muscles with TMS of the affected hemisphere was the most obvious abnormality. Also, central conduction time was significantly prolonged in the remaining patients. The mean amplitude of the affected hemisphere MEPs was diminished. The amplitudes of the unaffected hemisphere MEPs recorded from the intact side were enhanced especially in the first week following the stroke. During TMS, only the blink reflexes were elicited from the periorbital muscles due to stimulus spreading to trigeminal afferent nerve fibers. It is concluded that perioral muscles are innervated by the corticobulbar tract bilaterally. CFP caused by a stroke is generally incomplete and mild because of the ipsilateral cortical and multiple innervations out of the infarction area, and recovers fast through cortical reorganisation

Sympathetic skin responses in adult humans during sequential swallowing

WOS: 000313863200002PubMed ID: 23290172Study aims.-Autonomic changes, especially those of sympathetic skin responses (SSR), during sequential water swallowing (SWS) have not been systematically investigated. This study aims to electrophysiologically examine these autonomic changes (SSR and heart rate) that occur during 50 ml sequential water swallowing from a cup. Materials and methods.-Fifty-eight normal healthy adults were included in the study. Their submental muscle activity, respiratory activity, heart rate changes, and sympathetic skin responses were recorded during 50 ml water swallowing. In addition, we requested subjects to imagine drinking water as they did just before. The same recordings were performed during this imagination period. Results.-SSR appeared at the beginning and at the end of SWS in 52% of subjects. A first sympathetic skin response was evoked at the onset of SWS, and a second one appeared 8.6 +/- 1.7 seconds after the first one and at the end of swallowing. Similar double SSRs were also obtained during imagination in most investigated subjects (33 out of 35 of selected subjects in a total group of 58 subjects). Swallowing tachycardia was observed during the SWS-associated apnea period, but not during the imagination period. Heart rate significantly increased during the SWS-associated apnea period. Conclusion.-The first SSR that appeared at the onset of swallowing is likely related to arousal. The appearance of a second response is a novel finding, which is probably related to the activity of subtil corticosubcortical networks. While discrete/single swallows can be used to evoke SSRs, SWS is unlikely to be clinically useful in its current form. In contrast, swallowing tachycardia could be a useful tool to examine dysphagic patients. (C) 2012 Elsevier Masson SAS. All rights reserved