We report a patient with central and extrapontine myelinolysis (CPM/EPM) who did not demonstrate any electrolyte disturbance during the course of the disease. A 53-year-old male with a history of alcoholism and diabetes mellitus, complained of progressive gait disturbance, dysarthria and dysphagia. He developed gaze nystagmus on upward gaze and rebound nystagmus to the primary position from upward gaze. The electronystagmogram showed saccadic pursuit, impairment of visual suppression and markedly impaired optokinetic nystagmus, although saccadic ocular movement appeared normal. Auditory brainstem response demonstrated prolonged I-V and III-V inter peak bilaterally. T2-weighted MR imaging demonstrated high-intensity areas at the bottom of the pons and middle cerebellar peduncle bilaterally. A diagnosis of central and extrapontine myelinolysis was based on the clinical course and MRI findings. An alcoholic history and hyperglycemia might have contributed to the development of CPM/EPM in this patient.
Vestibular compensation is attributed to functional and structural reorganization of neural networks in the central vestibular system, but its precise mechanism is still not clear. Immediate early gene c-Fos is used as a marker of neuronal activation, because of its very limited expression in the normal state and quick appearance after stimulation. Previous reports, investigating c-Fos expression after unilateral labyrinthectomy were made in rats and guinea pigs, but not in the mouse brainstem. For future application to the gene knockout mouse, we examined c-Fos expression in the mouse after unilateral labyrinthectomy. Twenty-four hours after surgery, a highest number of c-Fos positive cells were observed in the bilateral medial vestibular nucleus (MVe), spinal vestibular nucleus (SpVe) and in the contra lateral prepositus hypoglossal nucleus (PrH). In the inferior olive nucleus (IO), c-Fos positive cells were significantly higher in the intact side.
This study investigated the effect of information within visual fields on postural control. Thirty-six undergraduate and graduate students participated in the experiment. The body sway was measured while participants watched static visual stimuli presented in the central visual field, the peripheral visual field, and the full visual field. Squares that differed in sizes were used as stimuli to provide similar visual information in each visual field. The result showed that body sway was reduced when the stimulus was presented in the peripheral visual field relative to when it was presented in the central visual field. This result suggests that information of the peripheral visual field may play an important role in postural control.
Caloric testing is one of the most valuable examinations for evaluating vestibular function. Recently, air caloric stimulation has been more widely utilized than irrigation with water. Using air has several advantages as follows; 1. possible to be performed by a clinical laboratory technician only, and 2. possible to be applied to patients with otitis media, 3. possible to avoid discomfort caused by water in the external ear canal. However, there is no agreement about the detailed method of air caloric stimulation. This study intended to establish the stimulation standards of the air caloric testing. We studied 16 normal subjects as well as 6 patients with unilateral peripheral vestibular dysfunction. Bi-thermal (30°C and 44°C) and uni-thermal (20°C) methods were applied using air and water stimulation, respectively. With regard to maximum slow phase velocity, air and water caloric stimulation could deliver corresponding response, under the conditions of 20°C and 44°C temperature. However, a significant difference was observed at 30°C, which showed a weaker response using air caloric stimulation. Caloric unilateral weakness was similarly demonstrated by air as well as water irrigation. And there was no significant difference in CP% between air and water caloric stimulation. Air caloric testing seemed to be an alternative to the traditional method of water irrigation, though the appropriate value for the low temperature in cases receiving bi-thermal stimulation remains controversial.
To describe methods and strategies to advance the basic science underlying all interventions in ENT, this paper reviewed some areas of medical statistics that have gained prominence over the last 5-10 years: meta-analysis, evidence-based medicine, and cluster randomized trials. This study considers several issues relating to data analysis and interpretation, many relating to the use and misuse of hypothesis testing, drawing on recent reviews of the use of statistics in medical journals.
This paper reviewed the literature evaluating medical treatment in patients with vertigo and a MEDLINE literature search for the years 1966-2002 was performed using these search terms: labyrinth disease, drug therapy, clinical trials or randomized controlled trials. The search identified 351 clinical trials including 84 randomized controlled trials (RCTs) specifically examining drug therapy for vertigo published between 1966-2002. There were a large number of articles describing the effectiveness of cardiovascular agents, histamine antagonists and/or cholinergic antagonists in treating vertigo. Thirty-eight studies involving scopolamine and 31 studies involving betahistine were identified, 17 and 10 of which were RTCs, respectively. Only 3 of 13 studies involving steroids and 3 or 13 studies involving diuretics were RTCs and there was no RTCs concerning the use of aminoglycosides. Only one review assessed the effects of betahistine in Meniere's disease was identified by searching the Cochrane Library. This review, however, concluded that there was insufficient good evidence on the effect of betahistine in Meniere's disease, because there were no trials with a low risk of methodological bias. Based on these results, a large randomized clinical trial using the highest level of diagnostic criteria and outcome measures should be required to obtain better evidence regarding medical treatment on vertigo.