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This study aims to translate and cross-culturally adapt the throat scale of the Voice Handicap Index to the Brazilian Portuguese language.uracy.This was performed in five phases translation, synthesis, back translation, review, and pretest. Fifty subjects participated in the pretest, of which 22 participants had chronic cough, 13 had laryngopharyngeal reflux, and 15 had behavioral dysphonia. Of the 50 participants, 40 were female and 10 male, with an average age of 44 years and six months.In the translation process, only question four had to be translated by a fourth judge. After the back-translation and committee review steps, it was necessary to make adjustments to questions one, four, five, seven, eight, nine, and 10. With regard to question five, the "never" option was significantly associated with the clinical group with behavioral dysphonia (P = 0.016), and with regard to question eight, the option was occasionally significantly associated with the clinical group with laryngopharyngeal reflux (P = 0.015). For question six, all the response categories of the questionnaire, had a significantly higher proportion compared to "not applicable" (P0.001). For the other questions, no participants selected the "not applicable" option.The translation and cross-cultural adaptation of the throat scale of the Voice Handicap Index to Brazilian Portuguese was performed successfully; the Voice Handicap Index in Brazilian Portuguese prepared herein was called the Índice de Desvantagem Vocal-Garganta.

In clinical practice it may be difficult to evaluate the cause of acute dysphonia and aphonia. With the aim of elucidating the aetiology, diagnosis and management of patients with acute voice disorder, we have studied different populations with acute laryngitis and psychogenic voice disorder (PVD). The results indicate that bacterial infection is common only in patients with acute laryngitis (65%) whereas asthma-like symptoms are reported in a high proportion of patients with PVD (37%). The two populations are rather similar with regard to age, gender, smoking habits, perceptual features of dysphonia and occurrence of concomitant minor laryngeal abnormalities. Neurogenic disorders may sometimes give rise to peculiar vocal symptoms with rapid onset, here illustrated by two clinical cases: bilateral recurrent nerve palsy with acute onset of aphonia, and mutism due to sclerosis multiplex of the brain.

The starting point of this study was that two of the authors independently experienced vocal fatigue when singing after they had played their wind instruments. We studied six subjects who played fl...

From a cohort of 113 children, followed prospectively from birth during the first three years of life regarding different aspects of acute otitis media (AOM), two study groups were selected for the present investigation: 13 children with recurrent AOM (rAOM, i.e. at least six episodes of AOM during a 12–month period), and 29 children without any AOM episode. The purpose of this study was to analyse the possible effects of early onset rAOM on language development as assessed at four and seven years of age at phoniatric and linguistic examinations performed blindly. There were no differences between the two groups on any of the linguistic analyses performed, although the rAOM group manifested a somewhat better performance on auditory discrimination tests at four years of age. The results of the present study show that rAOM during the first three years of life, in otherwise healthy children, does not cause a detectable delay of language development at four and seven years of age.

Background Symptoms from throat (sensation of globus; frequent throat clearing; irritated throat) are common in patients referred to voice clinics and to ENT specialists. The relation to symptoms of voice discomfort is unclear and in some cases patients do not have voice problems at all. Instruments for patients' self-reporting of symptoms, and assessment of handicap, such as the Voice Handicap Index (VHI), are in common use in voice clinics. Symptoms from throat are however only marginally covered. Purpose: To develop and evaluate an instrument that could make the patients' estimation of symptoms from the throat possible. Further to facilitate the consideration of the relation between throat- and voice problems with the Throat subscale together with a Swedish translation of the Voice Handicap Index. Finally to try the VHI with the Throat subscale: the VHI-T, for test-retest reliability and validity. Methods A subscale with 10 throat related items was developed for appliance with the VHI. The VHI was translated to Swedish and retranslated to English. The questionnaire was tried in two phases on a total of 23+144 patients and 12+58 voice healthy controls. The reliability was calculated with Cronbach's alpha, ICC and Pearson's correlation coefficient. The validity was estimated by independent T-test. Results The difference in VHI-T scores between the patients and the voice-healthy controls was significant (p = < 0,01) and there was a good correlation of the test- retest occasions. The reliability testing of the entire questionnaire showed an alpha value of r = 0,90 and that for the Throat subscale separately a value of r = 0,87 which shows a high degree of reliability. Conclusions For the estimation of self-perceived throat and voice problems the scale on throat related problems together with the present Swedish translation of the Voice Handicap Index, (VHI) the VHI-Throat, proves to be a valid and reliable instrument. The throat subscale seems to help revealing a category of symptoms that are common in our patients. These are symptoms that have not earlier been possible to cover with the questionnaires designed for use in the voice clinic.

Forty consecutive patients with psychogenic voice disorder were studied prospectively to shed light on some problems of differential diagnosis met by the otolaryngologist. The females (n = 35) were on average younger than males (n = 5) (mean age 34.5 vs 51.8 years, respectively). Although an upper respiratory tract infection preceding the voice disorder was reported by no more than 25% of the patients, as many as 40% had been treated with antibiotics on one or more occasions. Other treatment and voice rest had been prescribed to a further 20% of the patients. The frequency rate of reported asthma/allergy-like symptoms (37.5) exceeded the incidence of asthma/allergy in the normal Swedish adult population. Minor laryngeal abnormalities found in 10 patients could be rejected as causative since they were inconsistent with the voice disturbance. In most of the patients (n = 27), vocal function returned to normal or improved after voice therapy combined with counselling. Vocal abnormalities remained unchanged in three patients. The patients who required multiple therapy sessions (n = 10) were older (mean age 48.8 years) and seemed to have more profound personal problems than the average. The findings suggest that psychogenic voice disorder may often be misdiagnosed as acute laryngitis or asthma/allergy. Restricted use of antibiotics and other drugs is to be recommended in the treatment of benign voice disorders.

The aim of the present paper was to evaluate the possible impact of methacholine challenge on the voice and vocal tract in 10 patients reporting hoarseness due to presumable hyperreactivity to some environmental factors. Ten age and gender-matched healthy subjects served as controls. Methacholine was used for hypersensitivity challenge and saline solution (0.9% NaCl) as control substance. Subjects were examined on two separate challenge occasions testing either methacholine in increasing doses (3, 6, 12 mg) or NaCl. Voice recordings, videolaryngoscopy, and measurement of nasal secretion were performed before and after each sniffing session. Subjective complaints were documented. Data were statistically analyzed with three-way analysis of variance and group comparisons performed. Perceptual analysis of voice recordings showed an increase of the grade of voice disorder in patients after exposure to both substances. Moreover, one of the patients became aphonic and another severely dysphonic after NaCl. No voice quality changes were detected in controls. The videolaryngoscopy findings divergent from normal did not increase in any group. Nasal secretion was significantly higher after sniffing of methacholine than NaCl in both groups. The frequency of subjective complaints was equal in both groups after both substances. However, there was a qualitative difference in the character of the symptoms: the patients complained of throat, vocal, and nasal symptoms whereas the controls complained exclusively of nasal symptoms. The study supports the view that vocal dysfunction after exposure to non-specific environmental irritating factors may be triggered mainly by emotional mechanisms such as off-warding reaction or dissociative disorder.

We evaluated the effects of different electrical parameter settings on the intelligibility of speech in patients with Parkinson's disease (PD) bilaterally treated with deep brain stimulation (DBS) in the subthalamic nucleus (STN). Ten patients treated with DBS for 15 +/- 5 months (mean, SD) with significant (P < 0.01) symptom reduction (Unified Parkinson's Disease Rating Scale III) were included. In the medication off condition, video laryngostroboscopy was performed and then, in random order, 1 1 DBS parameter settings were tested. Amplitude was increased and decreased by 25%, frequency was varied in the range 70 to 185 pps, and each of the contacts was tested separately as a cathode. The patients read a standard running text and five nonsense sentences per setting. A listener panel transcribed the nonsense sentences as perceived and valued the quality of speech on a visual analogue scale. With the patients' normally used settings, there was no significant (P = 0.058) group difference between DBS OFF and ON, but in four patients the intelligibility deteriorated with DBS ON. The higher frequencies or increased amplitude caused significant (P < 0.02) impairments of intelligibility, whereas changing the polarity between the separate contacts did not. The settings of amplitude and frequency have a major influence on the intelligibility of speech, emphasizing the importance of meticulous parameter adjustments when programming DBS to minimize side effects related to speech. (Less)

Background factors, symptoms and signs were analysed in 40 consecutive patients with psychogenic dysphonia. Their voice profile was compared with that of 40 patients with infectious laryngitis. The majority of the patients were young females, non-smokers, who were not professional voice users. Criteria for acute infectious laryngitis prior the voice disorder were met in no more than 10% of the patients. Nevertheless as many as 40% of the patients had been treated with various antibiotics. The prevalence of reported asthma/allergy-like symptoms was high, 37.5%. Perceptual analysis of voice profiles demonstrated similarity of aberrancies in psychogenic dysphonia and in acute laryngitis. Since it may be difficult to distinguish psychogenic dysphonia from acute laryngitis, careful analysis of anamnestic data may be helpful for a correct diagnosis.

Summary It is generally accepted that psychogenic voice disorder (PVD) is aresult of psychosocial stress; however, systematic studies of etiological factors in this condition are few. Furthermore, although immediate effects of therapy are estimated to be good, relapses are frequent, and the long-term effects of therapy are not known. The present prospective and longitudinal study on 30 patients was thus focused on possible etiological factors, the course of therapy, and the long-term results of therapy for PVD. The results indicate that interpersonal conflicts related to family and work are of basic importance in precipitating this condition. PVD is interpreted as a specific disorder of verbal emotional expression. Our therapy model in which vocal exercises are performed, together with training of communicative skills, seems rewarding. Relapses were not reported in 88% of the patients during the followup period of 1.9-8.4 years after therapy.

Moraxella catarrhalis and Hemophilus influenzae are isolated from the nasopharynx in 50% to 55% and 8% to 15%, respectively, of cases of acute laryngitis in adults. This finding indicates that these organisms, M catarrhalis in particular, are in some way involved in the pathogenesis of the disorder. In the present double-blind, placebo-controlled trial, the effect of erythromycin ethylsuccinate (0.5 g twice a day for 5 days) on the elimination of nasopharyngeal pathogens and reduction of clinical signs of upper respiratory tract infection, as well as on subjective complaints, was evaluated in 106 adults with acute laryngitis. The bacterial isolation rates at presentation were M catarrhalis 50%, H influenzae 18%, and Streptococcus pneumoniae 4%. In the 99 patients who completed the study, the elimination of M catarrhalis after 1 week was better in the erythromycin group (25 of 30 cases) than in the placebo group (6 of 19 cases; p ≤ .00038). The elimination of H influenzae was unaffected by erythromycin. Otolaryngologic examination did not reveal any significant group differences regarding laryngitis, pharyngitis, or rhinitis. Voice quality was improved after 1 week, irrespective of treatment. However, as compared to the placebo group, the erythromycin group reported fewer voice complaints after 1 week and fewer coughing complaints after 2 weeks. As acute laryngitis in adults is self-limiting, and subjective symptoms are spontaneously reduced after 1 week in most cases, antibiotic treatment does not seem warranted as a general policy. However, erythromycin may be justified in patients who are professionally dependent on voice function.

Previous studies of acute laryngitis in adults have shown high nasopharyngeal isolation rates of B. catarrhalis and H. influenzae. Phenoxymethylpenicillin had no effect on the clinical course. In the present study, 106 patients with acute laryngitis were treated with erythromycin 0.5 g x 2 V or placebo. During the first week the isolation rate of B. catarrhalis was reduced from 60 to 10% in the erythromycin group compared to 34 to 27% in the placebo group (p less than 0.01). The elimination of H. influenzae, isolated in 19% at the acute visit, did not differ between the two groups. As compared to controls, erythromycin treated patients reported significantly lower scores of subjective voice disturbance after 1 week and cough after 2 weeks. Laryngological examination and voice evaluation failed to reveal any differences between the groups.

The effect of intravenous administration of two sedatives, diazepam (0.3 mg/kg) and thiopental (6.0 mg/kg), on the vestibulo-ocular reflex (VOR) in man was investigated on 9 volunteers. The VOR was evoked with a velocity step rotation test and gain and time constant of perrotatory and postrotatory nystagmus were measured. Both drugs reduced VOR gain. Diazepam-induced reduction lasted 8 h and thiopental-induced reduction 1 h. A reduction of the VOR time constant was found lasting about 1 h for both drugs, but with a tendency for the thiopental effect to last longer. These findings, not previously described in man, differ from what has been found in macaques and rabbits injected with diazepam. The reduction of gain and time constant were not correlated with the blood concentration of either drug. The present results suggest that in man the VOR gain and time constant are both reduced by different types of sedatives although with different time courses. On the basis of previously shown effect of alertness on the VOR, it is hypothesized that diazepam and thiopental, besides having a specific effect on central nervous system structures important to the VOR, also induce reduction of the VOR through a general sedation of the CNS.

Fourteen patients with vestibular neuritis were examined at onset of symptoms and after one year. Postrotatory time constant and gain in the vestibulo-ocular reflex (VOR) were measured after rotation with a velocity step of 150 deg/s. There was no significant difference in gain towards the healthy side at onset of the disease compared to recordings after one year. The time constant towards the healthy side was significantly shorter at onset compared to measurements after one year. The results reflect the loss of unilateral vestibular function on the velocity storage mechanism, both in the acute situation and after compensation. The findings indicate that reduction of the time constant in the VOR is not only due to unilaterally vestibular impairment but it is also an effect of the generally reduced activity in the vestibular system after a lesion and may act as protective mechanism in acute vertigo.

Eye movements in 30 patients with brain-stem lesions were evaluated with electro-oculography, and the findings were analyzed with regard to the site of the lesion in the brain stem. Eye velocities generally were reduced more severely in pontine than in medullary lesions. In medullary lesions, there even was a slight enhancement of the velocities in the fast component of optokinetic and postrotatory nystagmus. In contrast to the slow-phase velocity of OKN, which often was preserved in medullary lesions, the smooth-pursuit velocity was reduced in lesions at all levels in the brian stem. This indicates that these two types of visually induced eye movements use different mechanisms.

A review of the treatment of vestibular disorders with drugs is presented. In animal experiments, administration of certain drugs, e.g. alcohol, barbiturates and chlorpromazine, retards the vestibular compensation, while others, e.g. caffeine, amphetamine and ACTH, accelerate the compensation. In compensated animals, some drugs produce overcompensation and some decompensation. A double-blind, randomized trial of the effect of scopolamine and dimenhydrinate in patients with vertigo of varying origin showed, as compared with placebo, that these drugs did not significantly alleviate the vestibular imbalance. The reason for the poor efficacy of the treatment may have been overcompensation of vestibular function loss and adverse effects caused by the drugs. Care should be taken that the drugs used do not retard the vestibular compensation caused by the central nervous system.

Peak velocities of voluntary saccades and fast phases of different qualities of nystagmus were studied in 20 normal subjects, 5 patients with pontine lesions and 5 patients with lesions in the frontal cortex. The peak velocity of saccades was related to the amplitude of the eye movement, the alertness of the subject and whether the subject could see the target or not. The effect of the age was not significant. The quick phases of caloric, optokinetic and angular acceleration induced nystagmus were equally rapid but somewhat slower than that of vestibular nystagmus recorded in standardized visual surrounding. In the same visual condition saccades were always faster than quick phases of nystagmus. Patients with cortical lesions had normal velocities in saccades and quick phases of nystagmus. Patients with pontine disorders had significantly reduced saccadic and quick phase velocity, and some of the patients exhibited dissociations between velocity pattern of rapid eye movements. The velocity difference between saccades and quick phases probably reflects different pontine mechanisms while the somewhat higher velocity in quick phase of vestibular nystagmus recorded in light is probably related to higher attention evoked by vestibular-visual interaction.

The effect of transdermally administered scopolamine (TTS-scopolamine) (2.5 cm2 surface area, one and two patches) and dimenhydrinate (100 mg) on experimental motion sickness was examined in 16 healthy volunteers in a randomized double-blind study. Nausea was induced by Coriolis manoeuvre and vertigo by calorization of the ear. In all subjects, scopolamine was found in urine in concentrations indicating adequate absorption of the drug. One TTS-scopolamine, two TTS-scopolamine and dimenhydrinate caused a statistically significant reduction in nausea when compared with placebo. Dimenhydrinate was somewhat more effective against nausea than one TTS-scopolamine. Vertigo was significantly reduced after dimenhydrinate and two TTS-scopolamine. Side effects of both drugs were negligible, though gait disturbances and vertigo could occur occasionally after two TTS-scopolamine. No dose-response relationship was found between the urinary excretion of scopolamine and alleviation of nausea. Dimenhydrinate and TTS-scopolamine are both effective against motion sickness, the latter provided it is applied 6 to 8 hours before exposure to the stimulus causing the motion sickness.

Tracking eye movements were studied in 20 healthy subjects and in 24 patients with vestibular neuronitis, disorders within the frontal cortex, the cerebellum or the brain stem. The tracking tests were performed at six different target velocities between 10-60 degrees s-1 and different parameters were evaluated. The maximum velocity gain of smooth pursuit as normal in the group with vestibular neuronitis but reduced in the groups with disorders within the frontal cortex, cerebellum and the brain stem. The total amplitude of tracking and amplitude of smooth pursuit were normal in the groups with vestibular neuronitis and frontal cortical disorders, while in the groups with cerebellar and brain stem disorders it was reduced. The frequency of superimposed saccades with amplitude range of 3-10 degrees was significantly increased in all groups; however, in the group with vestibular neuronitis the increase was significant only during tracking in the direction of spontaneous nystagmus. The number of superimposed saccades with amplitude range of 11-20 degrees was significantly increased only in the group with cerebellar disorders. The frequency of square waves was not significantly increased in any group. Quantitative analysis of tracking eye movements seems to be a valuable aid for evaluation of site of lesions in the central nervus system.

Gain (eye velocity/stimulus velocity) of vestibular and optokinetic nystagmus, gain of smooth pursuit, and degree of visual suppression of caloric nystagmus were estimated in normal subjects and in patients with vestibular neuronitis, and disorders in frontal cortex, cerebellum or brain stem. It was found that the visual tests discriminated better between disorders of central origin than did the vestibular test. Visual suppression of caloric nystagmus was more frequently defective in patients with decreased gains of optokinetic nystagmus and smooth pursuit than in patients with normal results on visual tests.

Saccades, smooth pursuit and angular acceleration induced nystagmus were analysed quantitatively in 10 patients with speech dyspraxia. The saccades were less accurate, had a prolonged reaction time and showed a tendency to reduced peak velocity, though only contralateral to the lesion. Smooth pursuit was imparied, with a reduction in maximum velocity gain. The vestibular responses tended to be hyperactive, indicating facilitated brain-stem reflexes. The findings show that a lesion in the frontal eye field can produce various oculomotor disturbances, in which the triggering of eye movements and their control, and pacing of the various movement sequences are disturbed. In addition, anticipation of a movement pattern requiring volition may be greatly impaired.

Branhamella catarrhalis was isolated from the nasopharynx in 55% of 40 noncompromised adult patients suffering from acute laryngitis. Diplococcus pneumoniae and haemophilus influenzae were found in another 5 and 8%, respectively; one patient had group A streptococci in the throat specimen. In 90% of the patients the laryngitis complaints were preceded by symptoms of an acute respiratory tract infection. Two of the patients with B. catarrhalis showed a significant titre conversion against influenza B and parainfluenza type e virus, respectively. Attempts to isolate virus failed in all cases. The results indicate that B. catarrhalis, known to cause acute otitis media in small children and respiratory tract infections in adult compromised hosts, may be involved in the etiology of acute laryngitis in otherwise healthy adults.

The effect of transdermally administered scopolamine (TTS scopolamine) (release rate 5 micrograms/h) and dimenhydrinate (100 mg) was examined on optovestibular nystagmus in 16 volunteers in a randomized double-blind trial. A statistically significant decrease in the optokinetic part of nystagmus was observed during all treatments. Most profound reduction was found during treatment with two TTS scopolamine. The vestibular part was reduced by treatment with two TTS scopolamine, only. The results indicate that scopolamine and dimenhydrinate exert their effect in motion sickness by reducing the vestibular and visual influx and by partly inhibiting the integrative functioning of the vestibular nuclei. In their action, the motion sickness drugs seem to assist the cerebellum by diminishing impulses from various orientation reflexes in order to preserve the functional capacity of the central nervous system. Different symptoms in motion sickness seem to arise when the vestibular gain operates beyond the normal range of the cerebellar control mechanisms.

(1988). Acute Laryngitis in Adults: Diagnosis, Etiology, Treatment. Acta Oto-Laryngologica: Vol. 105, No. sup449, pp. 31-31.

The effects of i.v. injection of diazepam 0.3 mg/kg and thiopental 6.0 mg/kg on vestibulo-ocular reflex (VOR) were studied in 9 healthy volunteers. One hour after injection of both diazepam and thiopental VOR gain was reduced and time constant shortened. Four hours after intravenous injection of diazepam the VOR gain was still significantly reduced and had not yet returned to control 8 h after injection. Although both drugs were detected in blood still 8 h after the injection, there were no longer significant effects on VOR. Moreover, individual values of VOR gain and time constant did not correlate with the blood concentrations of the drugs. Decrease of VOR gain and shortening of time constant after i.v. given diazepam and thiopental in man are interpreted as resulting from both specific effects on VOR and non-specific reduction of alertness.

The number of saccades, vestibular gain and visual suppression as a function of smooth pursuit gain were determined in 10 cerebellar cases. Visual suppression increased and the number of saccades decreased with increasing smooth pursuit gain while a high vestibular gain was found in most cases but without relation to the gain of smooth pursuit. An eye-motor model is presented according to which all findings could be related to a disturbance of proper cerebellar processing of optic impulses and of impulses to the vestibular nuclei in the paramedian reticular formation.

The pathogenesis of idiopathic contact granuloma is still not clear. The present results of a prospective study on possible etiological factors indicate that oesophageal disturbances are common in patients with contact granuloma but some other pathogenetic factors must also be considered.

Peak velocity of saccade, maximum velocity of smooth pursuit, and peak velocity of slow phase of vestibular and optovestibular nystagmus were measured three times daily on three separate days in 6 healthy subjects in order to estimate the intra-individual variation of the results of oculomotor tests. Analysis of variance revealed that the oculomotor performance of the individual subjects varied systematically, depending on whether the tests were performed in the morning, at noon, or late in the afternoon. In particular, the velocity of saccade displayed lowest values in the afternoon. The present results indicate that oculomotor performance may depend on the individual biological rhythm of fatigue; however, it is also possible that eye motor behaviour is coupled to an independent rhythm of motor activity. Circadian rhythmicity of oculomotor performance should be considered in follow-up studies and in examination of patients with reduced vigilance.

Saccadic eye movements provide important information about the neuron system at several levels. In recent years computer analysis of saccades has been adapted for use in clinical work. The most common detection methods do not always function without the user's control and aid. In the present paper a digital filter is described for the detection of saccades. This non-recursive filter unscrambles saccade data which has been collected during the execution of an algorithm. The method is suitable for use with microcomputers. The filter is adaptive. Two concise experiments using the method are described.

The peak velocities of saccades and fast phases of nystagmus were examined and compared in 20 healthy subjects. The peak velocities of both types of eye movements increased with increase of amplitudes. The saccades were found to be fastest in light, slower in darkness and slowest behind closed eyelids. The peak velocities of the quick phases of optokinetic and of vestibular nystagmus were found to be the same. Fast phases of optovestibular (optic as well as vestibular stimulation) nystagmus produced significantly higher peak velocities than the two others. At the same amplitude and during the same visual conditions the saccades were significantly faster than any type of fast components of nystagmus. The difference in velocity between voluntary and reflexive eye movements is possibly related to differences in antagonistic activity during these eye movements, but also to specific synaptic events during the voluntary action.

Patients with acute laryngitis following an upper respiratory tract infection are often treated with antibiotics for their voice complaints, although, to our knowledge, the effect of such therapy has not been examined. In the present study, comprising 100 adults with laryngitis, the rate of resolution of vocal symptoms, as estimated from voice recordings or subjectively by the patients, was the same in patients who received penicillin V (pcV) as in those who received placebo. Similarly, the degree of rhinorrhea/nasal congestion and cough was not significantly influenced by pcV treatment. At the acute visit, nasopharyngeal cultures revealed Branhamella catarrhalis in 50%, Hemophilus influenzae in 15% and Streptococcus pneumoniae in 1% of the patients; the rate of elimination of these bacteria was the same in the pcV as in the placebo group. Thus, while suggesting that B catarrhalis and H influenzae are important for the pathogenesis of the disorder, our results do not provide support for the use of pcV in acute laryngitis.

Voluntary tracking eye movements were analysed in 20 normal subjects whose gaze was fixed on a visual target moving at six different constant velocities between 10 degrees s-1 and 60 degrees s-1. Tracking ability was quantified according to four parameters. The mean value and dispersion of each parameter at each velocity were determined. The maximum velocity gain of smooth pursuit was, on average, 0.98-0.75, gradually diminishing with increasing target velocities of 10-60 degrees s-1. Amplitude of smooth pursuit decreased gradually and was replaced by superimposed saccades at increasing target velocities. Saccades with amplitudes of 3-10 degrees were present at all target velocities, while those greater than 10 degrees occurred mostly at target velocities above 30 degrees s-1. Square waves were rare but equally frequent at all target velocities and seemed to occur randomly during tracking eye movements. An additional group of 9 subjects was investigated twice. Mean values of maximum velocity gain of amplitude of smooth pursuit and of frequency of superimposed saccades were higher on the second occasion, probably reflecting the effect of learning. Co-operation and interaction of the smooth pursuit and the saccadic subsystems to produce the voluntary tracking were discussed.

The accuracy and velocity of voluntary saccades together with the velocity of fact phases of nystagmus were studied in 26 patients belonging to 4 groups with defined neurological disorders. Patients with speech disorders of the dyspraxia type, indicating the lesion in the left frontal cortex, showed a pronounced decrease in saccadic accuracy in combination with normal saccadic and quick phase velocity. Patients with pontine disorders showed a significant decrease in the peak velocity of saccades and quick phases of nystagmus while the accuracy of the saccades ranged from normal to severely disturbed. Patients with acute meningo-encephalitis showed increases in peak velocity of saccades and of quick phases of nystagmus and the accuracy was somewhat reduced. Patients with a labyrinthine disease showed normal velocity of saccades and of quick phases as well as normal accuracy of saccades.

The eye tracking test is today a well established part of clinical otoneurological examination. In the present paper some applications of the test in evaluating of the level of lesion within the vestibular system are reviewed.

The effects of diazepam and thiopental on voluntary saccades and pursuit eye movements were tested in 9 volunteers, with an interval of at least 2 weeks between tests. One, 4 and 8 h after intravenous injection of diazepam (0.3 mg/kg) or thiopental (6.0 mg/kg), voluntary saccades and pursuit eye movements were tested and blood samples taken for analysis of drug concentration. As compared to results of tests without drugs, a significant reduction both of saccadic peak velocity and gain of pursuit eye movements was found 1 h after injection of either drug, but not after 4 and 8 h. The amplitude of saccades elicited with the 60 degrees stimulus was significantly reduced 1 h after injection of diazepam. Latency of saccades increased significantly up to 4 h after injection of either drug. No significant correlation was found between peak velocity of saccades and blood concentration of either thiopental or diazepam 1 h after administration. The present results confirm that in man saccades and pursuit eye movements are reduced by benzodiazepines and barbiturates, but provide no support for the previously described efficacy of saccades in monitoring the effect of benzodiazepines. It is hypothesized that diazepam and thiopental also induce reduction of voluntary saccades and pursuit eye movements via a general sedation of the central nervous system (CNS), besides having specific effects on CNS structures important to the performance of voluntary eye movements.

Postural control is maintained by sensory feedback from visual, vestibular and somatosensory receptors. Recently several methods for evaluating postural control have been devised, utilizing an imposed perturbation. Most of these methods use stimuli which simultaneously affect more than one of the sensory feedback loops. In the present paper a posturographic technique is presented with specific loading of the proprioceptive system, using a computer controlled vibratory stimulus and computerized analysis of the results.