Glycerol effect for endolymphatic hydrops is well known as an improvement in pure tone threshold at three hours after glycerol administration. However, a long time effect of glycerol is unknown. In this study, audiometric tests were administered during ten hours after glycerol administration in order to determine the long time effect of glycerol in cases of Meniere's disease, sudden deafness and normal subjects.The following results were obtained;1) The long time effect including rebound phenomenon of glycerol in the pure tone threshold did not appear in cases of sudden deafness and normal subjects.2) The long time effect of glycerol in the pure tone threshold was observed only in cases of Meniere's disease and it was classified into the following four types, “descending type”, “descending and ascending type”, “ascending type” and “unchanged type”.3) In the classification of audiometric types, the crest type and rising type were mainly occupied by “descending type” and “descending and ascending type” and the falling type was mainly occupied by “ascending type”.4) The half of Meniere's disease showed rebound phenomenon in the pure tone threshold.
During the past 14 years from 1975 to 1989, two-nation-wide surveys of Meniere's disease have been carried out by the Vestibular Disorders Research Comittee of Japan, supported by the Ministry of Health and Welfare of Japan. However, an epidemiological case-control-study including normal subjects has not yet been performed by this committee.In this third survey, therefore, 148 patients with definite Meniere's disease, 138 with non-Meniere vertigo, 113 with rhinolaryngological disorders, and 165 normal control subjects were collected by the 16 mem-bers of the Research Committee from June 1990 to November 1990. The controls were selected to match as closely as possible the sex, age and location of the Meniere's disease patients.The characteristic epidemiological features of Meniere's disease in Japan were :1) Sex-ratio : 63 males to 85 female.2) Age-distribution : Peak at 40-49 years for males and 30-39 years for females.3) Season and Time of Onset : Often initial vertigo attacks occurred in the afternoon or in the morning.4) Occupational Distribution : There was a higher incidence of Meniere's disease among technicians or white-collar workers than among farmers, laborers engaged in blue-collar work, as in the 1st and 2nd surveys. However, the number of house-wives was lower in this 3rd survey.5) Personal characteristics : In patients with Meniere's disease, precisionism and neurosis were more frequently observed than in non-Meniere's vertigo.6) Preceding Events : Mental and physical fatigue before vertigo attacks was frequent in Meniere's disease patients.These epidemiological features reconfirm that the occurrence of vertigo attacks in Meniere's disease is influenced much more by individual factors than by environmental factors, as was found in the 1st and 2nd Nation-wide surveys. However, a marked difference in sex ratio with female preponderance was found in the 3rd survey.The incidence of bilateral Meniere's disease was 16.2% (24/148), higher than in the 1st and 2nd surveys.
Two cases of horizontal eye movements disorders due to pontine lesions are reported and their clinical symptoms described. Case 1, a 52-year-old female, showed right lateral gaze paralysis together with right facial paralysis, vestibular dysfunction and scanning speech after surgery on an epidermoid cyst in the 4th ventricle. Case 2, a 56-year-old female, displayed right lateral gaze paralysis combined with right facial paralysis, vestibular dysfunction, right deafness and left hemiplegia following pontine hemorrhage. The right lateral gaze paralysis of both cases were analyzed and speculated to have resulted from combined disorders of the right abducens nucleus, the right PPRF (paramedian pontine reticular formation) and the right MLF (medial longitudinal fasciculus) in the pontine tegmentum.
The case of a 26-year-old female with a laryngeal paraganglioma after treatment for a carotid body tumor is reported with a review of the literature. She first visited our department with a chief complaint of hoarseness in 1994. We found a submucosal tumor in her supraglottic area. She had been treated for a carotid body tumor at another hospital in 1989. We operated for the submucosal tumor by laryngofissure. The histopathological diagnosis was paraganghoma. The tumor has not recurred since the operation. Laryngeal paraganghoma is rare in the head and neck. In Japan, this is the first report of both laryngeal paraganglioma and carotid body tumor occurring in one persons. We also discussed the clinical characteristics of the laryngeal paraganglioma and the multiple characteristics of paraganglioma of the head and neck.
The present experiment examined the influence of asphyxia on neuronal activities of the primary vestibular neurons in guinea pigs.These results were obtained as follows:1. During asphyxia, spontaneous firing in a total of 33 units analyzed disappeared with or without transient increase of discharges.2. Recovery of discharge was seen in 6 units (18%) within 3 minutes.3. Increments of firing rates during asphyxia were larger in irregular and intermediate firing units than in regular units.
Between 1978 and 1981, Feldmann's osteopathic approach was often used to manage chronic middle ear disease. In this procedure, the superior and posterior segment of the ear canal wall was cut after complete mastoidectomy, removed temporarily and re-positioned in the previous position after handling the diseased focus in the tympanic isthmus area. Forty-one cases (24 cases of non-cholesteatomatous chronic otitis media and 17 cases of cholesteatoma) were followed and long-term results of this procedure were studied with regard to re-operative findings following this procedure. Among the 41 patients, 13 (31.7%) required revision surgery because of cholesteatoma formation, infection etc. Seven of these 13 patients (53.8%) required revision surgery because of cholesteatoma formation after this procedure. None of these 7 cases appeared to involve residual cholesteatoma. The most important problem is that 3 of the 7 patients showing cholesteatoma formation had non-cholesteatomatous chronic otitis media before this procedure. In other words, the Feldmann's osteoplastic approach may iatrogenically induce cholesteatoma formation in non-cholesteatomatous chronic otitis media. The re-operative findings indicated that the re-positioned canal wall in this procedure may have small bony defects or bony erosion, inducing pocket formation through these defects to create a new cholesteatoma. Although recent literature concerning tympanoplasty recommends posterior canal wall reconstruction using cartilage, bone, ceramic material or bone-pate rather than the canal wall down method, careful follow-up should be continued with regard to pocket formation and/or cholesteatoma formation.
We correlated the surgical findings and the findings of computerized tomographic scans of the temporal bone in 38 ears from 38 patients with Meniere's disease (31 unilateral and 7 bilateral) treated by endolymphatic sac (ES) drainage surgery between 1986 and 1991. At surgery, the position and size of the ES were recorded. The position of the ES was classified as one of three types according to Arenberg's parameters (type I, type II and type III) and the size of the ES was classified as large, intermediate or small. Scans encompassing the lateral semicircular canal were used to measure the minimum distance between the posterior semicircular canal and the posterior petrous surface (P-P distance). The P-P distance in 23 type III cases was significantly shorter (2.25 mm) than in 13 type II cases (3.39 mm). The P-P distance in 9 large-sized ES cases was significantly longer (3.99 mm) than in 20 intermediate-sized ES cases (2.40 mm) and in 9 small-sized ES cases (1.92 mm). Significant correlations were found in patients with Meniere's disease between a short P-P distance and type III ES position, and also between a short P-P distance and an intermediate or small-sized ES.
In facial palsy, the function of the chorda tympani probably reflects the intracanalicular pressure of the Fallopian canal because the nerve fibers of the chorda tympani can withstand pressure better than the motor fibers of the facial nerve even when the intracanalicular pressure is increased. The intracanalicular pressure in the Fallopian canal is caused by nerve degeneration and swelling.We transsected the facial nerves of guinea pigs and observed nerve degeneration and swelling. We found that the swelling of the nerve began about 8 hours after nerve transsection and continued for about 14 days and then decreased gradually. Therefore, we concluded that the salivary flow and salivary pH tests, which are the methods of testing the function of the chorda tympani, should be done between 8 hours and 14 days after the onset of facial palsy.
Reports on facial nerve schwannoma have been gradually increasing, and it is no longer a rare disease. We have had 4 cases of facial nerve schwannoma in our clinic since October, 1978, when our clinic opened. The first case (a 34 year-old, female), a small schwannoma was found in the tympanic portion of the facial nerve when she underwent a tympanoplasty for cholesteatoma. The second case (a 45 year-old, female), suffered from slowly progressive facial nerve palsy and later from severe vertigo. The third case (a 73 year-old, male), experienced severe vertigo with long-term facial palsy, while the fourth case (a 60 year-old, male), suffered from sudden onset of slight facial palsy with a subauricular tumor. The patients with facial nerve schwannoma complained of various symptoms such as facial nerve palsy, hearing disturbance, vertigo or dizziness, tinnitus, otalgia or headache, depending on the site of occurrence and tumor size. A multitumor type of schwannoma originating from a single facial nerve such as case 4 is rare. We reviewed the literature covering 11 cases of the multitumor type of facial nerve schwannoma. When we encounter a facial palsy patient with fluctuating degrees of palsy, in addition to the variety of symptoms mentioned above, and who does not response to extensive treatment, a diagnosis of schwannoma is considered. Accordingly, the pathway of the facial nerve, from the CP-angle to the parotid gland is carefully examined. MRI is a suitable method for examination.
High resolution transverse axial CT encompassing the lateral semicircular canal was used to study the visualization of the vestibular aqueduct and to measure the minimum distance between the posterior semicircular canal and the posterior petrous surface (P-P distance) in Meniere's disease and chronic otitis media. The results indicate that the development of the bone between the posterior semicircular canal and the posterior petrous surface, which usually contains the endolymphatic sac, is significantly poorer in affected ears than in nonaffected ears in unilateral Meniere's disease, and much poorer than in chronic otitis media.
