摘要:

Five patients with idiopathic sudden sensorineural hearing loss (ISSHL) were examined by a combination of high-resolution computed tomography and special magnetic resonance imaging techniques. By three-dimensional constructive interference in steady state magnetic resonance imaging excellent visualization of the membranous labyrinth was obtained. No fibrous or osseous obliteration of the intralabyrinthine fluid spaces was observed in all investigated temporal bones. The results provide further evidence for a viral pathogenesis of ISSHL.

ISSN:0301-1569    

DOI:10.1159/000276599

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The Research Committee of the Ministry of Health and Welfare in Japan has defined hearing loss of unknown etiology with fairly high-speed progression as idiopathic bilateral sensorineural hearing loss (IBSH). Its diagnostic criteria consist of the following: that it is (1) progressive, (2) with bilateral involvement, and (3) of unknown etiology. In this study, we evaluated the clinical course in 20 cases of IBSH. Many cases of IBSH finally showed symmetrical profound sensorineural hearing loss. The clinical course of IBSH consisted of various combinations of the following four states: (1) fixed hearing, (2) rapid progression, (3) pathological slow progression and (4) physiological slow progression.

ISSN:0301-1569    

DOI:10.1159/000276600

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Following direct antigen challenge to the endolymphatic sac (sac), the relation of caloric test results and spontaneous nystagmus to the histological changes of the sensory epithelium of the vestibular organ and perilymph antibody levels was investigated in the guinea pig. In a secondary keyhole limpet hemocyanin (KLH) challenge to the sac, irritative nystagmus was followed by paralytic nystagmus and a suppression of caloric reaction. These findings correlated well with the degree of degeneration of the sensory epithelium of the vestibular organ and the levels of perilymph antibody. On the other hand, neither phosphate-buffered saline inoculation nor primary KLH challenge to the sac nor a secondary KLH challenge to the intradural space resulted in a disturbance of the vestibular function. These results suggest that the immune response of the sac may possibly be an important key to the pathogenesis of Ménière’s dise

ISSN:0301-1569    

DOI:10.1159/000276601

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Intense sound induces a temporary or permanent threshold shift. The aim of this study is to make an experimental model for temporary threshold shift (TTS) using guinea pigs. In this study, two kinds of sound exposure were used for inducing a threshold shift in the guinea pig; one of 110 dB SPL at 10 kHz for 10 min and the other of 120 dB SPL at 10 kHz for 5 min. The former condition produced different levels of reduction in compound action potential (CAP) immediately after sound exposure and different steady levels of CAP amplitude after recovery (within 120 min) in 10 guinea pigs. The latter condition produced a total loss of CAP amplitude immediately after sound exposure in 8 of 9 guinea pigs, and this condition continued for 120 min in 7 of the 9 guinea pigs. Additionally, in 2 of 3 guinea pigs which were exposed the sound of 120 dB SPL at 10 kHz for 5 min, the CAP amplitudes were almost the same as those of control animals 1 day after the exposure. One the basis of these results, we consider the sound of 120 dB SPL at 10 kHz for 5 min to be the optimal intensity and frequency of sound and duration of exposure for producing a TTS in the guinea pig.

ISSN:0301-1569    

DOI:10.1159/000276602

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Vestibular dark cell areas in gentamycin (GM)-intoxicated guinea pigs were examined ultrastructurally and cytochemically. After GM treatment the dark cells represented cytoplasmic vacuoles, wide intercellular space, less osmiophilic cytoplasm and irregularly shaped basal portions. Cytochemically, Na+, K+-ATPase activity was demonstrated on the basolateral folded plasma membranes of the dark cells similarly in both GM-intoxicated and control guinea pigs. These findings revealed that the dark cells still possessed a function of regulating the ionic composition of the endolymph, although they showed various structural changes. On the other hand, the melanocytes extended their cytoplasmic processes into the basement membrane and the intercellular space of the dark cells. Melanosomes markedly increased in number dose-dependently by GM treatment. The significance and the function of the melanocytes in the dark-cell areas are discussed.

ISSN:0301-1569    

DOI:10.1159/000276603

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The surgery of cerebellopontine angle tumors has shown remarkable progress over the last 20 years due to improved microsurgical techniques. However, the dissection of the facial nerve may lead to postoperative paresis as the result of the surgical trauma and the disruption of blood supply over a large distance. The functional status of the nerve can be intraoperatively monitored by means of intramuscular electromyography of facial muscles and direct electrical stimulation. In this study, the impact of monitoring techniques on the preservation of facial function was evaluated by comparing monitored (n = 30) and unmonitored (n = 34) patients. Both groups were comparable with regard to the size of the tumor, the surgical approach and the duration of operation. All patients were operated by the same surgeon (T.L.) either via the middle fossa or the translabyrinthine approach. The EMG was recorded with needle electrodes from the orbicularis oris and oculi muscles. For electrical stimulation, bipolar forcep electrodes were used delivering rectangular, constant current pulses of 100 µs duration and a current strength between 0.05 and 0.8 mA. The mechanically or thermally elicited activity by drilling, direct manipulation or coagulation consisted of bursts and trains which are signs of minor nerve impairment. Their occurrence can lead to a modified surgical technique with a more precise preparation around and at the facial nerve. The immediate postoperative nerve function was normal or showed only a minor impairment (classes I and II according to House and Brackmann) in 87% of the monitored as compared with 74% of the unmonitored patients. The rate of severe long-term paresis (classes V and VI) was 3 vs. 6%. The results show the benefit of intraoperative monitoring for postoperative facial nerve function, particularly in larger tumors

ISSN:0301-1569    

DOI:10.1159/000276604

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Smooth pursuit (SP) and saccades (SC) as well as nystagmus were recorded with electro-oculography in 21 healthy subjects with manifest non-paralytic strabismus. A normal SP function under binocular conditions could be recorded in 67% of the subjects and complementary monocular recordings increased the figure to 81%. The corresponding figure for the SC test was 38 and 67%, respectively. However, a minority of the subjects presented a normal test result under both binocular and monocular conditions. Spontaneous nystagmus and/or nystagmus after headshaking was present in 67%. These findings may indicate that subjects with strabismus have a combination of a ‘subclinical’ vestibular and oculomotor dysfunct

ISSN:0301-1569    

DOI:10.1159/000276605

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We investigated the postcaloric nystagmus related to positional change. Twenty-two healthy subjects were examined (experiment 1). A caloric test was carried out in the supine position. Following the cessation of the primary phase, the subject was reoriented to the upright position. An additional 10 subjects were also examined with other positional changes (experiment 2): following the cessation of the primary phase, the subject was reoriented to the lateral positions, irrigated-ear-up and irrigated-ear-down positions. As a control study, 6 subjects were examined without positional change (experiment 3). In 37 (84%) ears, postcaloric nystagmus was observed in the upright position. Furthermore, in 12 of 20 (60%) ears in the irrigated-ear-up position and in 13 of 20 (65%) ears in the irrigated-ear-down position, the horizontal component of postcaloric nystagmus was observed. Without positional change, no postcaloric nystagmus was observed. These findings indicate that caloric nystagmus is modified by an adaptive process and that postcaloric nystagmus as it relates to positional change might be attributed mainly to the vestibular adaptation.

ISSN:0301-1569    

DOI:10.1159/000276606

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Heparin, in concentrations of 250, 2,500 and 25,000 IU, was applied topically to the edge of tympanic membrane (TM) perforations, standardized in size, once daily until the perforation had closed. At 2 months, the animals were killed and the TMs subjected to otomicroscopic and light microscopic studies. The day that closure of the TM perforations was complete (median 8 days) was the same for the various heparin groups as for the sterile water-treated controls. However, regarding opacity of the healed TM area, heparin affected the TM in a dose-dependent manner. The TMs that had been subjected to the highest concentration of heparin were the most transparent and showed the least sclerosis. When compared for thickness, the TMs treated with the higher concentration of heparin were considerably thinner than those treated with the lower concentration. The sterile water-treated controls were all thicker than the heparin-treated TMs. It is inferred that glycosaminoglycan heparin improves the quality of the healed area of TM perforations.

ISSN:0301-1569    

DOI:10.1159/000276607

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The aim of this study was to investigate if there is a correlation between symptom score and response to histamine challenge in patients suffering from non-allergic nasal hyperreactivity. Eighteen patients with perennial rhinitis entered the trial. All had negative skin prick tests and normal total IgE. The nasal mucosa was challenged with three histamine concentration levels, 1, 2 and 4 mg/ml. The objective response was recorded with rhinostereometry and was compared to symptom scores estimated by the patients on a visual analogue scale. With simple analysis of regression there was a significant correlation when challenging with 2 mg/ml (R = 0.695, p < 0.01) and 4 mg/ml (R = 0.569, p < 0.05). The results indicate that the model could be useful for objective assessment of the degree of non-allergic nasal hyperreactivity.

ISSN:0301-1569    

DOI:10.1159/000276608

出版商:S. Karger AG    

年代:1994

数据来源: Karger