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A survey of 265 Japanese patients with Meniere's disease revealed bilateral involvement in approximately 29% of all these patients. Somatic and psychiatric aspects of bilateral Meniere's disease were as follows. (1) The duration of the disease in cases of bilateral involvement was significantly longer than cases of unilateral involvement. (2) An abnormal general condition, a more extensive degree of hearing loss and neurotic type were frequently diagnosed in cases of bilateral involvement. Based on these results, it was concluded that psychiatric management and prevention of aggravation of deafness should be part of the management of treatment in bilateral Meniere's disease.

We report a case of Granulocytic Sarcoma (chloroma) with acute mastoiditis in a 14-year-old male. The patient was brought to our clinic because of left facial nerve palsy and acute bilateral otitis media. He was diagnosed as having acute mastoiditis, and underwent left mastoidectomy. One week later, however, leukocyts increased and the wound did not heal. A mass lesion in the mastoid was detected on MRI. We biopsied the mastoid and found Granulocytic Sarcoma (chloroma). Thereafter, the patient underwent chemo- and radiation therapy, but died due to the general deterioration of his condition. In this case, pathological examination and MRI were useful for establishing the final diagnosis.

We report a patient with a cavernous haemangioma of the internal auditory canal (IAC). A 47-year-old man presented with a left profound hearing loss and a left facial palsy that had progressed over 5 years. With a preoperative diagnosis of acoustic or facial nerve neurinoma, the tumour was removed totally by a translabyrinthine approach. Intraoperatively, the tumour appeared red; it compressed the facial and cochlear nerves, and adhered to the vestibular nerve. The tumour was diagnosed as a cavernous haemangioma upon histologic and immunohistochemical examination. No recurrence of tumour occurred, but hearing loss and left facial palsy persisted. Although cavernous haemangiomas of the IAC is found in small size less than 10 mm, they often cause severe hearing loss and facial palsy. Our patient had no improvement of facial palsy, but many reports describe recovery of facial nerve function.

Autoimmune ear disease induced by type II collagen has been investigated by Yoo et al. In the present study, we investigated the effects of direct chronic infusion of type II collagen specific monoclonal antibodies into guinea pig cochlea. Type II collagen fragment CB11 peptide specific monoclonal antibodies (CB11 Mabs) were infused directly into the scala tympani of guinea pig using Alzet mini-osmotic pump (CB11 Mabs group). As a control, normal mouse serum was infused using the same method (control group). To evaluate the auditory function, brain stem auditory-evoked potentials (BAEPs) were recorded. In the CB11 Mabs group, 80% of the animals showed increased hearing threshold of more than 25 dB, 7 days after implant. This hearing threshold shift continued until the end of this study. The hearing threshold shift observed in guinea pigs of the control group was minimal (15 dB or less). To detect the structural changes, histopathologic studies were performed using hematoxylin and eosin staining. Inflammatory cell migration was detected mainly in the scala tympani of the guinea pigs of both groups. In CB11 Mabs group, endolymphatic hydrops and atrophic change of the organ of Corti were also observed. These results of this experiment suggest that type II collagen autoimmunity is responsible for the production of hearing loss and endolymphatic hydrops.

Myelin protein P0 has been identified as an autoantigen in inner ear disease. In order to study autoimmune hearing loss, we performed brain stem auditory-evoked potentials (BAEPs) studies on P0-sensitized mice. Two-P0 sensitized mice showed hunched posture, poor coat, loss of body weight, and abnormal walking with a waddling gait. About 25% of the P0-sensitized mice developed hearing loss. In the BAEPs study, peak latencies of waves I, III, and V and interpeak latencies (IPLs) I–III were prolonged in the P0-sensitized hearing loss group of mice. Hearing thresholds were elevated in this group of mice in comparison with control mice. Inflammatory cell infiltration was observed in the cochlear nerve region, and a reduced number of spiral ganglion cells was also detected. These results suggest that P0-sensitized mice are a useful model for studying autoimmune inflammation of the peripheral portion of the auditory system.

Sera from patients with various inner ear diseases, especially Meniere's disease, were investigated by Western blot against guinea pig inner ear preparations. Of 45 patients, 24 (53%) with various inner ear diseases had antibodies against inner ear proteins, compared with none of 10 (0%) in control subjects without inner ear diseases. Of the 10 proteins that showed a positive reaction with patient sera, the 28-kD band was unique in that it appeared only in the membranous fraction of the inner ear and was highly positive (28%) in reaction with Meniere's disease patient sera. The results in the present study with proteins extracted from guinea pig inner ears were consistent with our previous study with proteins from human inner ear. It suggests that the 28-kD protein may be a candidate for detecting autoimmune inner ear disease (AIED).

Few reports have characterized auditory processing in monaural stimulation, which is important to the understanding of auditory brain activity in subjects with hearing loss. We therefore measured regional brain activity in response to monaural stimulation of 95 dB SPL monosyllables using functional magnetic resonance imaging (fMRI) in subjects with normal hearing and five with unilateral deafness as controls for ‘cross-hearing’. Images were analyzed by statistical parametric mapping software. In subjects without hearing loss, the stimuli elicited cortical activation in the primary auditory (BA 41) and auditory association regions (BA 42, 22), particularly contralaterally where extent of activation was approximately 2.5 times the ipsilateral extent. All patients with profound unilateral deafness showed no statistically apparent response in the primary auditory and auditory association regions, ruling out an important influence from cross-hearing. We found fMRI to be a useful technique for analysis of auditory processing that should be applicable to patients with various hearing abnormalities.

Since the publication of the article entitled "Placebo effect in surgery for Meniere's disease. A double-blind, placebo-controlled study on endolymphatic sac shunt surgery" by Thomsen et al. in 1981, endolymphatic sac surgery for Meniere's disease has tended to receive a lower evaluation. Investigators who read only its abstract were likely to understand that this study was well planned and performed under a doubleblind, placebo-controlled study and that the conclusion would be reliable. The results showed that only a minor difference (p

We reported a patient with cavernous hemangioma of the internal auditory canal. A 47-year-old man demonstrated progressive hearing loss and facial palsy on the left hand side over 4 years. A small tumor was detected in his left internal auditory canal by magnetic resonance imaging (MRI). The lesion displayed iso-signal intensity in T1-weighted images, high signal intensity in T2-weight images, and positive Gadolinium enhancement. Under tentative diagnosis as neurinoma, the tumor was totally removed by the translabyrinthine approach. The red tumor had compressed the facial and cochlear nerves, and adhered to the vestibular nerve in the internal auditory canal. It was diagnosed as cavernous hemangioma by immunohistochemical examination. There has not been any sign of recurrent tumors, but hearing loss and left facial palsy persisted after surgery. A cavernous hemangioma of the internal auditory canal tends to manifest with progressive hearing loss and facial palsy based on a review of past reports.

Patients with sudden onset deafness usually show marked hearing restoration, but in patients with sudden onset total deafness or near total deafness full hearing is sometimes not recovered.Between 1978 and 2000, we treated 247 patients with sudden deafness at our hospital, of which 71 had total deafness or near total deafness at the initial visit. In this retrospective study we divided patients into two groups: a total or near total deafness group (TD group), and the others group (O group). An analysis of case reports gave the following findings:1) There were no significant differences in age, sex, or the number of days from disease onset to initial visit between the two groups.2) The incidence of sudden deafness patients with vestibular symptoms in the TD group was significantly higher than in the O group.3) In the TD group, the rate of complete recovery and marked improvement was significantly lower than that in the O group.4) The rate of complete recovery and marked improvement in the TD patients with vestibule symptoms was significantly lower compared to those with similar symptoms in the O group.5) Hearing prognosis in sudden deafness patients with Grade 4a at the initial visit was poorer compared to patients with other Grades. However, 43.5% of sudden deafness Grade 4b patients recovered to Grade 1.

To clarify the clinical features of sudden deafness in the elderly, we investigated patients' profile and the prognosis of sudden deafness retrospectively. Of 224 patients with sudden deafness between 1978 and 1999, twenty-five patients more than 65 years of age were studied. The following results were obtained:1. The mean age of the patients was 70.8 years old, and there was no predominance in gender. The frequency of sudden deafness in the elderly has increased since 1998.2. Of 25 patients, 10 (40%) carried other systemic diseases at the onset of sudden deafness, such as diabetes mellitus, hypertension and liver dysfunction.3. The recovery of hearing loss in aged patients with sudden deafness was significantly worse than that in patients under 65 years of age.4. The aged patients tended to have various hearing losses in the contralateral ears. A poor prognosis of sudden deafness was noted in patients with hearing loss in the contralateral ear.

The endolymphatic-perilymphatic shunt operation between the scala media and scala tympani was performed in 22 guinea pigs with endolymphatic hydrops induced by the silver nitrate injection method 2 months before the operation. Two (n = 10), 7 (n = 6), and 28 (n = 6) days after the operation, the condition of the fistula and the inner ear pathology were studied histopathologically. In half of the animals, the fistula was open, whereas in the other half, the fistula was closed. In the group examined after 2 postoperative days, the animals with open fistulas showed a slight collapse of Reissner's membrane, which might indicate that excess endolymph escaped through the fistula into the scala tympani. In the groups examined later, especially in the group examined after 28 postoperative days, the animals showed distention of hydrops despite preservation of the fistula. Moderate-to-severe degenerative changes of the organ of Corti, macula sacculi, and stria vascularis were observed in the vicinity of the fistula. We conclude from this study that the endolymphatic-perilymphatic fistula created inside the cochlea apparently was not sufficient to reduce the hydrops. Rather, it caused degenerative changes of the inner ear structure. This type of surgery is not suitable for Meniere's disease.

212 patients diagnosed with sudden deafness between October, 1978 and April, 1998 were reported in our department. In order to clarify the relationship between sudden deafness and diabetes mellitus, the treatment course of 18 patients with sudden deafness, who were affected by diabetes, was analyzed retrospectively. The patients with sudden deafness were divided into two groups (diabetic and non-diabetic) and were analyzed. The following results were obtained:1) The mean age of patients in the diabetic group was 51.8 years, approximately 8 years older than the non-diabetic group. The number of patients with diabetes mellitus increased markedly in the last 10 years.2) There was no significant difference in hearing improvement after treatment as well as in hearing levels between the two groups.3) The rate of patients with dizziness or vertigo in the diabetic group was significantly higher than in the non-diabetic group. The patients with dizziness or vertigo showed a poorer prognosis in their hearing loss.4) There was no relationship between the duration of diabetes and the prognosis of hearing loss. The patients with retinopathy due to diabetes tended to show less hearing improvement.5) Steroid therapy for sudden deafness patients with diabetes was executed without worsening the diabetic condition if insulin was administered adequately.

We reported 10 patients with deafness due to mumps. The diagnosis was made according to the criteria for the diagnosis of mumps deafness determined by the Acute Profound Deafness Committee set up by the Ministry of Health and Welfare, Japan. We reviewed the clinical features and observed the following:1) The mean age of the patients was 18.1 years. The mean time of the onset of hearing loss was 6.1 days after the appearance of parotid swelling. All 10 cases had unilateral total or profound sensorineural hearing loss. Seven cases complained of dizziness.2) Nine cases were treated with steroid hormones, gamma globulin and vitamins. Hearing loss of eight cases did not improve, but one case recovered hearing in the low tone range. Dizziness disappeared in six cases, but in one case, dizziness persisted.3) In one case, delayed endolymphatic hydrops of the ipsilateral type was found 10 months after the onset of hearing loss due to mumps.

CATCH22 syndrome, as defined by D. I. Wilson, is associated with the following features: Cardiac anomalies, Abnormal facies, Thymic hypoplasia, Cleft palate, and Hypocalcemia resulting from microdeletions of chromosome 22q11. We encountered a patient with chronic otitis media, who was diagnosed as having CATCH22. We performed a right tympanoplasty and reported subsequent findings in this CATCH22 patient.The case was a 9-year-old female who complained of bilateral otorrhea. She was diagnosed with CATCH22 syndrome on the basis of clinical findings and a genetic analysis before visiting our clinic. Tympanoplasty revealed the handle of the malleus to be severely bent and ossicular movements seemed to be slightly restricted. Other anomalies were not observed. She was discharged without any further symptoms.

The atrial natriuretic peptide family (ANP family) is comprised of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP). These peptides regulate body fluid and blood pressure homeostasis as a neuropeptide in the central nervous system as well as a cardiac hormone in the periphery. To assess the possible physiological role of the ANP family, we investigated the immunohistochemical localization of these peptides in the rat inner ear. ANP-like and CNP-like immunoreactivities were observed in the spiral ligament just beneath the stria vascularis, spiral limbus, dark cell area, endolymphatic sac, spiral ganglion cells and vestibular ganglion cells. We could not detect specific BNP-like immunoreactivity in the inner ear. These observations were consistent with our previous study concerning the ANP family gene expression. The results suggest that the ANP family influences the metabolism of the inner ear fluid as well as afferent nerve activities in the inner ear.

We report two cases of pharyngeal foreign bodies that necessitated extracervical incision. The first case involved a 59-year-old woman who experienced a foreign body sensation in her throat after ingesting fish. No foreign body was found by esophagoscopic nor laryngoscopic examination. A CT scan however, showed a fish bone located near the thyroid cartilage. The second case occurred in a 71-year-old man who had a hernia of the nucleus pulposus in his neck. A foreign body, which was believed to be a wire, was found on the CT scan prior to the hernia operation. The wire was emdeded in the retropharyngeal space. An extracervical incision was required in both cases to access areas that were not visible during laryngoscopic examination. These cases highlight the importance of performing a CT scan even if no foreign bodies are found during laryngoscopic examination.

We analyzed 14 patients who showed a further progression of hearing loss after an initial examination of 214 patients with sudden deafness. They were divided into 2 groups based on the type of hearing loss progression. Group I consisted of six patients who displayed a rapid progression after increased hearing loss had begun. Group II consisted of eight patients who showed transient hearing improvement before an increase in hearing loss. The clinical features of the 14 patients were from a earlier visit to the clinics experiencing dizziness and/or vertigo with less recovery of hearing loss than the other patients. However, more than 60% of the 14 patients showed complete recovery or a marked hearing improvement. The predominant type of hearing loss was high tone loss at the initial audiological assessment in both groups. The flat type hearing loss was usually noted at the time when the patients experienced their greatest hearing loss. Although the details of the etiology of hearing loss progression remain unclear, group I was thought to be the slow type sudden deafness, whereas the deterioration of hearing loss in group II may be due to a circulatory disturbance of the inner ear.

Vasoactive intestinal polypeptide (VIP) is a 28 amino acid peptide that was originally isolated from porcine duodenum. The presence of VIP has been demonstrated in the central nervous system and peripheral tissues. However, there have been few reports on VIP as a neurotransmitter, especially in the inner ear. To investigate the function of VIP in the rat inner ear, we examined the expression of VIP and the VIP receptor by immunohistochemistry. Using the anti-VIP and VIP receptor antibodies, scattered fibres in the cochlear nerve trunk demonstrating VIP-like immunoreactivity were found, and the spiral ganglion cells demonstrated ring-shaped VIP-like immunoreactivity. Immunoreactivity for the VIP receptor was predominantly found in the spiral ganglion cells. Our results suggest that VIP may play an important role as a possible neurotransmitter not only in the local control of cochlear blood flow, but also in the auditory system.

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.

Cochlear blood flow (CoBF) and endolymphatic sac (ES) blood flow (ESBF) were measured in different groups of guinea-pigs by laser-Doppler flowmetry after the intravenous administration of various drugs through the jugular vein for 60 sec. These drugs included 50% glycerol, 70% isosorbide, 20% mannitol, 7% sodium bicarbonate and 1% diphenidol. For CoBF measurements, a probe was positioned on the basal turn of the right cochlea via a ventral approach. For ESBF measurements, it was placed on the right ES through the posterior cranial fossa via a dorsal approach. The average initial measured value of ESBF (8.31 +/- 2.97 ml/min/100 g) was significantly greater (p < 0.0001) than that of CoBF (4.33 +/- 1.15 ml/min/100 g). Following administration of most drugs except for diphenidol, both CoBF and ESBF increased immediately after administration; however, following diphenidol administration both CoBF and ESBF decreased. The magnitude of the CoBF response tended to be greater than that of the ESBF response (p = 0.006-0.112). It seems likely that this reflects anatomical differences in the vascular supplies, i.e. CoBF from the vertebrobasilar artery and ESBF from the external carotid artery. In addition, the presence of micropores or fenestrations in the ES vasculature may contribute to the differences between CoBF and ESBF.

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.

Between 1985 and 1995, 134 patients presented to our clinic with complaints of either dry mouth, decreased salivary flow or salivary gland swelling of unknown origin. These patients were diagnosed retrospectively based on the criteria established by the Sjögren's disease research committee (1977), and 30 patients were definitively diagnosed with Sjögren's disease while 23 were considered suspect. The gender distribution of these 30 patients was 25 female (83%) and 5 male (17%). The average patient age was 55.8 years for females and 42.6 years for males. Of 30 patients, 10 (33.3%) had only sicca syndrome and the other 20 (66.7%) had various complications such as collagen diseases, autoimmune diseases, and malignant lymphoid infiltration. Subjects included 14 cases of rheumatoid arthritis (RA), 1 case of systemic lupus erythematosus (SLE), 1 case of RA with periarteritis nodosa (PN), 1 case of progressive systemic sclerosis (PSS) with SLE, 1 case of PSS with Hashimoto disease, 1 case of malignant lymphoma and 1 case of RA with Waldenström's macroglobulinemia. Positive blood tests showed a relatively high incidence of elevated erythrocyte sedimentation ratios (ESR) (75%), elevated IgG levels (69.2%), positive anti-nuclear antibody (52.3%), positive anti SS A antibody (75%) and positive anti-SS B antibody (50%).

In this paper, the treatment by medication together with two maneuvers-the particle repositioning maneuver (PRM) reported by Parnes and Price-Jones and the liberatory maneuver (LM) reported by Semont et al.-were compared with treatment by medication alone. Fourteen of 15 cases (93.3%) treated with the PRM and 11 of 14 cases (78.6%) treated with the LM showed improvement after 2 weeks. These results were better than that obtained by medication alone, in which 8 of 26 cases (30.8%) showed improvement after 2 weeks. The most important benefit of these maneuvers seemed to be the speedier recovery than with medication alone, as there was no significant difference in the late success rate after 3 months between the maneuvers and medication alone.

An A to G mutation at nucleotide position 3243 of mitochondrial DNA is associated with mitochondrial encephalomyopathy, diabetes mellitus, and/or sensorineural hearing loss, which is maternally inherited. It is observed in about 1% of the patients with diabetes mellitus in Japan. Therefore, it is highly probable that otolaryngologists will encounter patients with hearing loss caused by the 3243 mutation. In this paper, we studied the audiovestibular characteristics of 8 patients who were identified as having the 3243 mutation (4 cases of mitochondrial encephalomyopathy and 4 cases of diabetes mellitus). Six of these patients had sensorineural hearing loss. The average age of onset of hearing loss was 30 years. The hearing loss was bilateral and symmetric, and was equivalent in all frequencies or increased from low to high frequencies. The hearing loss gradually deteriorated and the progression rate was 3.6dB per year on average. Hearing deterioration in patients with mitochondrial encephalomyopathy was faster than that in patients with diabetes mellitus. The audiologic examinations suggested both cochlear and retrocochlear impairment. Equilibrium function tests presented no significant characteristics, even in cases of severe hearing loss.

To investigate the differences in temporal bone development in various ear diseases--bilateral Meniere's disease (n = 13), unilateral Meniere's disease (n = 41), unilateral chronic otitis media (COM) (n = 25), temporal bone fracture (n = 9) and otosclerosis (n = 12)--the following 4 distances on a temporal bone CT slice encompassing the lateral semicircular canal (LSC) were measured by using the NIH Image program. These distances included the minimal distance between the posterior semicircular canal (PSC) and the posterior petrous surface (PPS) (P-P distance), the minimal distance between the PSC and the LSC (P-L distance), the minimal distance between the vestibule and the PPS (V-P distance) and the minimal distance between the PSC and the anterior margin of the sigmoid sinus (P-S distance). Both the P-P and V-P distances showed significant differences among the ear diseases, but the P-L and P-S distance did not. Meniere's disease showed significantly shorter P-P and V-P distance especially in bilateral Meniere's disease than those in COM and otosclerosis (p < 0.05). Affected ears in unilateral Meniere's disease showed a shorter P-P distance than non-affected ears (p < 0.01). In contrast, both ears with otosclerosis showed significantly longer P-P and V-P distances than those in Meniere's disease, COM (p < 0.01) and temporal bone fracture (p < 0.05). COM and temporal bone fracture showed intermediate P-P and V-P distances, without a difference between the affected and non-affected ears. In conclusion, the development of the posterior part of the temporal bone is reduced in Meniere's disease and greatly increased in otosclerosis. These findings by CT may be useful for diagnosing ear diseases.

A 30-year-old man was admitted to the Shiga Univ. of Medical Science for pyrexia, right otorrhea and right lateral neck swelling. He had not consulted a doctor despite his right otorrhea of 1 year's duration. He was diagnosed as having on extradural abscess and Bezold's abscess caused by chronic otitis media. He was treated with a mastoidectomy, trepanation and antibiotic therapy. Post operatively, he was asymptomatic.

The protective effect of piperacillin (PIPC) against ototoxicity induced by aminoglycoside was investigated in guinea pigs.In 13 animals, 0.1ml (4mg) per day of gentamicin solution was instilled into the left tympanic cavity on day 1 and day 4. The right ears of all animals were untreated. The PIPC treatment group, consisting of 7 animals, received an injection of PIPC solution (300mg/kg) intramuscularly from day 1 to day 5 while the control group, consisting of 6 animals, did not. Auditory brainstem response (ABR) in these animals was measured on day 1, day 4 and day 6.Significant changes were found in the hearing threshold of right ears in the PIPC treatment and the control groups. The increase in hearing threshold at day 4 and day 6 was significantly smaller in the PIPC treatment group (mean value: 22dB and 27dB, respectively) than in the control group (68dB and 88dB, respectively). The results of ABR in the present study indicate that PIPC has the potential to reduce aminoglycoside ototoxicity.

Several new maneuvers have been described recently which treat benign paroxysmal positional vertigo with head rotations to induce canal debris to move into the utricle. This study compared two maneuvers, the Particle Repositioning Maneuver (PRM) reported by Parnes and Price-Jones and the Liberatory Maneuver (LM) reported by Semont, with treatment by medication only. Thirteen of 15 patients (86.7%) treated with PRM and 8 of 9 (88.9%) treated with LM showed improvement after two weeks. These figures are higher than those obtained by medication alone, 8 out of 26 (30.8%). The superiority of these maneuvers appeared to be in the reduction of the duration of the disease, since an 80% success rate was obtained by medication alone after three months. LM seemed to be a better technique than PRM, since three patients who were not improved with PRM were then treated with LM, and two were cured and one improved.

In order to clarify the characteristics of severe cases of Meniere's disease (MD), we analyzed various epidemiological factors such as sex ratio, past history, complication, cause of onset of vertiginous attacks, etc., in a series of 958 patients with definite MD. Data were obtained from the three Japan-wide surveys of MD conducted by the Meniere's Disease Research Committee of Japan (1975-76) and the Vestibular Disorders Research Committee of Japan (1982-84 & 1990). Following the ideas proposed by the members of the Vestibular Disorder Research Committee of Japan, we divided severe cases into three categories according to the following criteria i) bilateral MD cases (BMD), ii) unilateral MD cases with prolonged disabled vertigo (UPDV), iii) unilateral MD cases with profound hearing loss (UPHL). About 40% of the subjects were classified as severe cases (UPDV: 23%; BMD: 9%; UPHL: 6%). The ratio of otitis media in past history was statistically different between severe cases and non-severe patients (p < 0.05), suggesting that otitis media in the past may contribute to the severity of Meniere's disease.

This study investigated whether dominant negative summating potential (DNSP) is absent at all stages of induced hydrops development, including the early stages of hydrops formations. Electrocochleography (ECoG) was done 3 days to 20 weeks after obliteration of the endolymphatic sac in guinea pigs, by electrodes attached to the cochlear bony wall on the scala vestibuli of the basal turn. DNSP was noticed only during the early stages of endolymphatic hydrops formation, before hydrops was fully developed. There was no DNSP when the distension of Reissner's membrane was marked. Increased endolymphatic pressure and/or changes in biochemical composition were thought to be the causes of DNSP.

Laryngeal amyloidosis is a rare disorder that is usually localized. We treated two patients with laryngeal amyloidosis and reviewed the clinical features of 86 cases of laryngeal amyloidosis reported in Japan. A 47-year-old male (case 1) and a 69-year-old male (case 2) complained of hoarseness. We found a tumor in the supraglottic region in case 1 and in the supraglottic to glottic region in case 2. Surgical resection with a laryngofissure was performed in each patient. Hoarseness was relieved in both patients. Since case 2 also had glottic cancer (squamous cell carcinoma), irradiation therapy with 60 gy of Co60 was administered after surgical resection. The most frequent symptom in the 86 cases reported in Japan was hoarseness, and the commonly affected sites were in the supraglottic and glottic regions. Patients must be treated by laryngofissure if the larynx is widely affected by amyloidosis as in our patients.

Two cases of facial paralysis of central nervous system origin are reported. One patient had the supranuclear type and the other the nuclear type of facial paralysis. The supranuclear type of left facial paralysis was due to a metastatic brain tumor (3×2cm) in the precentral gyrus of the right frontal lobe of a 67-year-old male. The original tumor was anaplastic squamous cell carcinoma of the lung. Although the lower portion of the left side of his face showed slight paralysis, the upper portion showed normal movement because of the double innervation of the upper portion of the face from both crossed and uncrossed corticobulbar fibers. The nuclear type of facial paralysis was due to a large epidermoid cyst located in the fourth ventricle of a 52-year-old female. The tumor was assumed to have depressed the right facial colliculus in the floor of the fourth ventricle resulting in the nuclear type of moderate right facial paralysis with normal stapedial reflex and normal gustatory function.

Endolymphatic sac (ES) blood flow (ESBF) and cochlear blood flow (CBF) were measured in different groups of guinea pigs by laser-Doppler flowmetry (Advance Laser Flowmeter, Model ALF 2100) after the intravenous administration of 70% isosorbide (1.6 ml/kg). The measurements were made under general anesthesia with intraperitoneal pentobarbital sodium. Respiration was controlled by a respirator after tracheotomy, and blood pressure was monitored through the femoral artery (Gould Statham P23 ID Pressure Transducer). For ESBF measurements, a probe was placed on the right ES after entering the posterior cranial fossa via the dorsal approach. For CBF measurements, a probe was placed on the basal turn of the right cochlea via the ventral approach. Isosorbide was administered intravenously through the jugular vein for 60 s. Both ESBF and CBF increased immediately after administration, reached a peak within 3-6 min and decreased gradually to their initial baseline levels in 11-15 min. Both blood flow changes almost always corresponded to systemic blood pressure changes, although a slight delay was observed in blood pressure compared to the blood flow. The magnitude of the CBF response tended to be greater than that of the ESBF response (p0.1). This may result from the anatomical differences in the two blood supplies, i.e., from the vertebral artery (CBF) and the external carotid artery (ESBF).

In 38 patients with Meniere's disease (29 unilateral and 9 bilateral) treated with surgical drainage of the endolymphatic sac (ELS) between 1986-1991, the surgical findings and temporal bone CT findings were correlated. At surgery the position and size of the ELS were recorded. The position of the ELS was classified into 3 types according to Arenberg's parameters (type I, type II and type III) and the size of the ELS was large, intermediate or small. CT 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 position ELSs was significantly shorter (2.25 mm) than that in 15 type I or type II position ELSs (3.29 mm). The P-P distance of the 9 large ELS was significantly longer (3.99 mm) than that of the 20 intermediate size ELSs (2.40 mm) and of the 9 small ELSs (1.92 mm). Significant correlations were found in Meniere's patients between the short P-P distance and the type III position, and between the short P-P distance and intermediate or small size ELSs.

A 5-year-old boy was hospitalized for intractable otorrhea and a polyp in his right ear. Pathological examination of the ear polyp revealed foreign body giant cells with severe inflammatory reaction. Two and a half years prior to his admission, he had received arthroplasty of the right temporomandibular joint (TMJ) with a diagnosis of joint ankylosis in the oral surgery department; a silicone sheet had been used to prevent reunion of the excised condylar head. A CT scan showed a spherical bony swelling of the joint, compressing the right external ear canal. A preauricular incision revealed an abscess surrounded by bone tissue in the right TMJ area which formed a fistula into the external ear canal. A silicone sheet 2cm×2cm was found inside the abscess and was removed. Daily change of gauze tampons through the ear canal fistula stopped the aural discharge, and the fistula closed in 20 days. Pathological examination of the ear polyp and CT scan were helpful in the diagnosis.

Based on the data obtained from two Japan-wide surveys of Meniere's disease (MD) conducted by the Meniere's Disease Research Committee of Japan (1975-76) and the Vestibular Disorders Research Committee of Japan (1982-84), the epidemiological characteristics of unilateral severe MD were evaluated among 810 patients with definite MD. Of these 230 had severe MD, 48 of them had with profound hearing loss (UPHL group) with a pure tone average of the affected ear at 500, 1000 and 2000Hz of 70dB or worse, and 182 had markedly disabling attacks of paroxysmal vertigo for more than 3 years (UDV group).1) The sex ratio in the UPHL group was 1 : 1, but there were more females than males in the UDV group.2) Age at onset of MD peaked in the third decade in the UPHL group, and in the fourth decade in the UDV group.3) In the past history, otitis media was significantly more common in both the UPHL and UDA group than in non-severe patients.4) Insomnia was more likely to cause vertigo attacks in the UPHL group than in non-severe patients.

In order to clarify the characteristics of the severe Meniere's disease we analyzed various epidemiological factors, such as sex ratio, duration of illness, etc., in a series of 958 patients with a definite Meniere's disease. The data were obtained from the three Japan-wide surveys of Meniere's disease conducted by the Meniere's Disease Research Committee of Japan (1975-76) and the Vestibular Disorders Research Committee of Japan (1982-84 & 1990). All subjects were classified into two groups : severe and non-severe. The former contained patients with bilateral and unilateral disease. Those with unilateral severe disease had suffered from markedly disabling attacks of paroxysmal vertigo for more than 3 years.1) There were 95 patients with bilateral disease, 238 with unilateral severe disease and 625 with non-severe vertigo. About 40% of the subjects had severe disease.2) Over half of the patients with definite Meniere's disease were females. (bilateral disease 64% ; unilateral severe disease 52% ; non-severe disease 53%)3) The average duration of illness in the severe group (bilateral, 7.1 years ; unilateral, 8.5 years) was longer than that in the non-severe group (3.3 years).4) The incidence of otitis media in the past history was higher in the unilateral severe group than in non-severe group.5) Changes in the atmospheric pressure and in the emotional state were more likely to trigger vertigo attacks in the severe group than in the non-severe group.

In this study we attempt to determine whether the dominant negative summating potential (DNSP) is present during the earlier stages of induced hydrops development. Electrocohleographs (ECoG) were taken 3 days, 4 days, 1 week, 2 weeks, 3 weeks, and 10-20 weeks after obliteration of the endolymphatic sac in guinea pigs with electrodes in the basal turn scala vestibuli.The action potential (AP) thresholds rose and the AP amplitudes decreased with time following surgery. The increases in the summative potential (SP) amplitudes and in the rises in the SP/AP ratios at 95 dB pe SPL in response to clicks tended to be greater 3 and 4 days postoperatively than subsequently. These results indicate that the potential for DNSP exists during the early stages of endolymphatic hydrops formation, before the hydrops is fully developed.