No abstract available.
Wounds and Injuries*

BACKGROUND AND OBJECTIVES: Dimenhydrinate is known to act on the vestibular system, causing vestiular suppression. But the effects related with therapeutic dosage on eye tracking tests and vestibulo-ocular reflex (VOR) are not clear yet. We performed this study to evaluate the effects of dimenhyrinate on eye tracking tests and VOR. MATERIALS AND METHODS: Twenty five healthy subjects, comprising of 12 men and 13 women between the ages of 15 and 69 (mean age=39) participated in this study. The assessment included saccade test, smooth pursuit test, optokinetic nystagmus test for eye tracking test and sinusoidal harmonic acceleration test for VOR test. Each test was performed before, and 2 hours and 4 hours after the oral intake of dimenhydrinate (therapeutic dosage: 50 mg). The subjects were kept alert by performing a calculation task and communicating with the investigator during tests. RESULTS: Analysis of results showed that latency was prolonged after 2 hours but was returned to initiae value after 4 hours. Gain was not changed in the saccade test as well as in the smooth pursuit test. Mean slow phase eye velocity (SPEV) decreased after 4 hours in optokinetic nystagmus test. Gain and phase lead decreased only at 0.01 Hz in sinusoidal harmonic acceleration test. CONCLUSION: Dimenhydrinate had minimal effects on eye tracking tests and VOR when the patient's alertness was kept during test.
Acceleration ; Dimenhydrinate* ; Female ; Humans ; Male ; Nystagmus, Optokinetic ; Pursuit, Smooth ; Reflex, Vestibulo-Ocular ; Research Personnel ; Saccades

Optokinetic nystagmus(OKN) is commonly employed in the assessment of central vestibular lesion. Asymmetry in the OKN has been found in lesions ipsilateral to the direction of the slow phase in parietal lobe, in brain stem, and in the cerebellum. Asymmetry of the OKN may also occur in peripheral vestibular lesions due to spontaneous nystagmus, and this may explain why even enhanced velocities of OKN are sometimes met in these patients. The ocular abnormality as congenital strabismus, extraocular paresis, and congenital nystagmus can cause abnormalities of optokinetic nystagmus. We investigated the clinical significance of OKN test and spontaneous nystagmus for differentiation of peripheral and central vestibular disorder. In this study, we recorded the optokinetic nystagmus by the electronystagmography. We divided the optokinetic response from normal to type III according to direction of the nystagmus and difference of(Rt-Lt) Vmean. At the result, all of the vestibuloneuronitis who had the optokinetic abnormality showed type I OKN abnormality with spontaneous nystagmus. Type II and type III OKN abnormality always appeared in central vertigo patients. Type I OKN abnormality could be seen in peripheral and central vertigo patient. But half of the central vertigo patients who had type I OKN abnormality did not have spontaneous nystagmus. We could not correlated OKN abnormality with specific location of central nervous system.
Brain Stem ; Central Nervous System ; Cerebellum ; Electronystagmography ; Humans ; Nystagmus, Congenital ; Nystagmus, Optokinetic* ; Paresis ; Parietal Lobe ; Strabismus ; Vertigo

Click sound can evoke myogenic potentials in active sternocleidomastoid(SCM) muscle. These are due to activity of vestibular afferent rather than cochlear, which produce very short latency inhibition of ipsilateral motor unit activity. We investigated the click-evoked vestibulocollic reflexes in neck muscles to find out the significance and relationship of latency and amplitude of myogenic potentials between two different methods of muscles activation. EMGs were recorded from surface electrode evoked by sound stimuli(95dB SPL, 5/sec repetitive rate, 512 times) over SCM muscles on each side. Myogenic potentials have two biphasic responses which were termed P1, N1, P2, N2 based on the polarity of their components. The subjects were 24 normal volunteers. EMG recordings were obtained from 12 subjects(Group 1) who keeped head 10 cm above ground in supine position to activate their neck flexors to the degree required through the averaging runs(bilateral SCM muscles activation method). EMGs from another 12 subjects(Group 2) were recorded by rotating head to the opposite side to activate SCM muscle throughout the procedure(unilateral SCM muscle activation method). The latencies and amplitudes of myogenic potentials in the SCM muscle after stimulation were analysed and compared between the two methods. The latencies(msec) of P1 and N1 were 11.2+/-2.4, 21.7+/-1.1 respectively in Group 1 and 13.3+/-2.4, 23.0+/-1.1 respectively in Group 2. The amplitude(uV) of P1-N1 were 38.78.1 in Group 1 and 33.28.1 in Group 2. There were no significant differences in latencies and amplitudes of P1 and N1 between the groups(p<0.05). Unilateral muscle activation is easier and comfortable than the bilateral muscle activation and there were no significant difference in latency and amplitude of P1. The myogenic potential of unilateral vestibular function loss disappeared in a patient who was labyrinthectomized but there was normal response of potential in a patient who is profound sensory neural hearing loss. Click evoked myogenic potentials is a simple method of examining vestibulocollic reflex. Click evoked myogenic potential is related to vestibular status.
Electrodes ; Head ; Healthy Volunteers ; Hearing Loss ; Humans ; Muscles ; Neck ; Neck Muscles ; Reflex* ; Supine Position

We investigated normal response of bithermal caloric stimulation after repeated monothermal caloric stimulation. 12 subjects were selected for cold(30degreesC) water stimulation. 8 subjects were stimulated by warm(44degreesC) water. After the bithermal caloric test, caloric stimuli(cold or warm) was repeated 5 times on both ear with a 10 minute time interval and the next bithermal caloric test was performed. Monothermal caloric stimuli was done at the same temperature as the previous test a day later. The bithermal caloric test was repeated after 4 days. We checked the maximum slow phase eye velocity(SPEV) and calculated the canal paresis and directional preponderance. The SEPV was changed from 26.4(+/-10.9) degrees/sec to 26.7(+/-20.5) degrees/sec in repeated warm stimulation; from 25.0(+/-11.4) degrees/sec to 27.3(+/-11.1) degrees/sec in cold stimulation. Canal paresis was changed from 12.4(+/-8.7)% to 6.3(+/-5.1)% in repeated warm water stimulation; from 9.6(+/-9.9)% to 6.9(+/-3.1)% in cold stimuli. Directional preponderance was changed from 11.9(+/-6.9)% to 8.7(+/-9.9)% in warm stimuli; from 11.5(+/-7.6)% to 10.6(+/-5.5)% in cold stimuli. There was no significant change of caloric response after repeated monothermal caloric stimulation.
Caloric Tests ; Ear ; Paresis ; Water

The endolymphatic secretory epithelium are stria vascularis in cochlear and dark cell in vestibule which are regulated by Na+-K+ ATPase. It is important that we study intracytoplasmic Na+-K+ ATPase for the physiologic research of inner ear. Recently cerium-based method for stain of Na+-K+ ATPase was developed. This study was underkaken to investigate the morphologic changes and Na+-K+ ATPase activity in stria vascularis and vestibular dark cell of mongolian gerbil after systemic intramuscular injection(200mg/kg or 300mg/kg) for 7days or local infiltration of streptomycin through round window. The results are as follows. 1) The strong Na+-K+ ATPase activity was seen at basolateral infoldings of marginal cell in stria vascularis but weak Na+-K+ ATPase activity in dark cell near transitional area. 2) There was no change of Na+-K+ ATPase activity in the stria vascularis and dark cell by systemic injection of streptomycin. The decrease of Na+-K+ ATPase activity in stria vascularis was seen at destruction site of infoldings by local infiltration of streptomycin but no changes in dark cell. 3) The ultrastructural changes of marginal cell by local infiltration of streptomycin were intracytoplasmic vacuole, partial loss of cytoplasmic infoldings, edema, and increase of melanin particle. but, there was no change of ultrastructure in dark cell except increase of melanin particle. The changes of ultrastructure of stria vascularis was variable by systemic streptomycin injection and there was no dark cell change except increased melanin particle. From the above results, the changes of ultrastructure and Na+-K+ ATPase were more severe by local infiltration of streptomycin through round window than systemic injection of streptomycin. The local infiltration of streptomycin through round window may be suitable method for the induction of inner ear damage.
Adenosine Triphosphatases* ; Cytoplasm ; Ear, Inner ; Edema ; Epithelium* ; Gerbillinae ; Melanins ; Streptomycin* ; Stria Vascularis ; Vacuoles

Acute labyrinthine infarction due to vertebrobasilar insufficiency results in acute vestibular and cochlear functional loss. It is very difficult to differentiate acute labyrinthine infarction from acute viral labyrinthitis, vestibulocochlear neuritis and sudden sensorineural hearing loss. Because its definite diagnosis criteria has not been yet established and confirmative diagnosis tool is limited, the diagnosis and appropriate treatment is more difficult. It is often misdiagnosed as a peripheral vestibular disorder because its clinical symptom is usually a form of dizzy attack with hearing impairment. We experienced a case of acute labyrinthine infarction due to vertebrobasilar insufficiency. We differentiated it from acute labyrinthitis and vestibulocochlear neuritis using ENG and diagnosed it by means of periodic ENG follow-up. Confirmative diagnosis was made by means of MR angiography. MR angiography shows non-opacification of right vertebral artery and focal stenosis of right basilar artery. We treated this patient with 500,000 unit of urokinase per day for 5 days and observed recovery of impaired vestibular and cochlear function.
Angiography ; Basilar Artery ; Constriction, Pathologic ; Diagnosis ; Ear, Inner ; Follow-Up Studies ; Hearing Loss ; Hearing Loss, Sensorineural ; Humans ; Infarction* ; Labyrinthitis ; Neuritis ; Urokinase-Type Plasminogen Activator ; Vertebral Artery ; Vertebrobasilar Insufficiency*

Laser surgery of allergic rhinitis has been reported to be successful by several authors, but there has been little study on factors that may help the physician select patients who are likely to respond to surgery. The aim of this study was to assess the factors that influence the surgical outcome of laser surgery for allergic rhinitis patients. We analyzed the data from questionnaire in 211 patients who were diagnosed as perennial allergic rhinitis and underwent CO2 laser surgery in our department from October 1993 to October 1995. All nasal symptoms including nasal obstruction, watery rhinorrhea and sneezing were significantly improved. Improvement rates do not differ according to the number of surgery, follow-up period, number of positive allergens and residency type. The results of this study suggest that laser surgery might improve nasal symptoms in patients with perennial allergic rhinitis. There was no significant difference in improvement rate in terms of both number of surgery and follow-up period.
Allergens ; Follow-Up Studies ; Humans ; Internship and Residency ; Laser Therapy ; Lasers, Gas ; Nasal Obstruction ; Surveys and Questionnaires ; Rhinitis* ; Sneezing ; Turbinates*

We investigated the vestibulo-ocular reflex which is followed by the change of angular acceleration in sinusoidal harmonic acceleration test. 20 normal volunteers with no evidence of previous otoneurologic disease were tested. The maximal slow phase eye velocity, gain and asymmetry were obtained in five different amplitudes of rotation, 30degrees, 60degrees, 90degrees, 120degrees and 150degrees with properly fixed conditions such as darkness and the frequency of rotation fixed at 0.05Hz. During each test, we asked the examinees to be alert and keep the eyes open. At least 5 minute interval was given between the tests and recalibrations were done before each test. The results of this test were as follows. 1) The maximal slow phase eye velocities were gradually increased according to the increment of the amplitudes of rotation with the statistical significances(p<0.05). 2) The gains were gradually decreased according to the increment of the amplitudes of rotation between the range of 30degrees and 90degrees with the statistical significances(p<0.05). 3) The asymmetries of each amplitude were the highest(13.6%) at 30degrees and the lowest(6.9%) at 120degrees, but there were no statistical significances(p>0.05). Therefore, from the above results, sinusoidal harmonic acceleration test with the frequency fixed at 0.05Hz, gain is higher when the amplitude of rotation is smaller and the pattern of the nystagmus is more evident when the amplitude of rotation is bigger. But The authors conclude that in order to get the results which are statistically significant, the amplitude of rotation should be lower than 90degrees.
Acceleration* ; Darkness ; Healthy Volunteers ; Reflex, Vestibulo-Ocular*

BACKGROUND AND OBJECTIVES: Vestibulo-ocular reflex and vestibulo-spinal reflex are induced by transmatoid galvanic stimulation of vestibular system. Nystagmus and body sway are result of each reflex. Recently, videooculograph possible to record a minute ocular movement was commonly used, vestibulo-ocular reflex induced by galvanic simualtion is easily documented. The purposes of this study are to evaluate the galvanic nystagmus in nomal persons in order to better understand the physiology of the vestibular system. MATERIALS AND METHODS: Eye movement of 20 neurootologic normal subjects by both side transmstoid galvanic stimulation (40cases) were analyzing by videonystagmography. RESULT: The direction of nystagmus in fast phase was to the negative electrode. Galvanic nystagmus was occured all normal subjects when stimulus intensity was more than 2mA. There was positive correlation between slow phase velocity(SPV) and electric current but negative correlation was noted between asymmery of SPV and electric current. CONCLUSION: It is suggested that the galvanic nystagmus test could be a new diagnostic tool for evaluation of vestibular status.
Electrodes ; Eye Movements ; Humans ; Physiology ; Reflex ; Reflex, Vestibulo-Ocular