Prognosis of Menière's disease by conservative treatment: retrospective study on the time course of the disease.

The incidence of Menière's disease was investigated in a total of 3222 patients with vertigo or dizziness who had visited Kitasato University Hospital during 1985-1991. Two hundred and fifty-one of the cases (7.8%) were found to suffer from Menière's disease and the male:female ratio was 1:1. Seventy cases of Menière's disease with complete records were classified into five groups, depending on the duration of the illness since its onset. Both ears were affected in 12 (17.1%) of the patients but in 4 (33.3%) of prolonged 12 patients having more than 15 years after the onset. All 70 patients had been treated conservatively, except for 3 who had undergone surgery. Frequency of vertiginous attacks and hearing impairment during the last year in each group were retrospectively compared with those of the other groups. No vertiginous attacks were experienced in 13 (24.1%) cases. The average number of vertigo attacks during the last year was 4.5 per year in 49 cases. Adequate therapy is desirable within one year after the onset of Menière's disease: the results showed the frequency of vertiginous attacks to be lowest and hearing levels to be best in the first group who were treated less than one year after the onset, in comparison with the other prolonged cases.

A case of cavernous hemangioma in the internal auditory canal.

A case of cavernous hemangioma in the internal auditory canal was reported. The chronology of this case was similar as one of Ménière's disease. The neurotological findings in this case were no specific findings to differentiate cavernous hemangioma from acoustic neurinoma. The high-resolution computed tomography (HRCT) revealed calcium stippling in the lesions, whereas magnetic resonance imaging (MRI) demonstrated a low signal intensity on both T1- and T2-weighted images. Comparison of HRCT and MRI findings is most useful for differential diagnosis of intracanalicular tumors.

[Neuro-otological study on Behçet disease].

It seems acceptable that pathological brain stem lesions exist in the patient with Neuro-Behçet disease (NB). However, only few reports have been published in this field. We report the neuro-otological findings in 33 patients who fulfilled the diagnostic criteria of Behçet disease completely or incompletely. The patients were classified into 2 groups: one is group of NB and the other is a group of Behçet disease without NB (non-NB). Furthermore, the latter was divided into 2 subgroups of patients with dysequilibrium and patients with normal equilibrium. They underwent equilibrium function tests, such as body balance test, gaze test, spontaneous and positional nystagmus test, eye tracking test (ETT) and optokinetic pattern test (OKP) by using electro-nystagmography (ENG). The following results were obtained. 1. Cerebellar and brain stem lesions were confirmed in all cases of NB group. 2. Most cases (6 of 8 cases) in the subgroup of dysequilibrium of the non-NB group showed peripheral vestibular disturbance. The other two patients were diagnosed to be vertebro-basilar insufficiency (VBI) and vascular Behçet disease with CNS disorder, respectively. 3. Nine of 13 patients in the normal equilibrium subgroup of the non-NB group were diagnosed to be neuro-otologically normal. However, we found two patients with peripheral vestibular disturbance and CNS disorder associated with hearing disturbance of the retrocochlear origin, respectively. 4. The neuro-otological examination is assumed to be useful to diagnose neuro-Behçet disease, to reveal the lesion site and the state of dysequilibrium in patients with Behçet disease.

Development of cellular polarity and tight junctions in parotid acinar cells of postnatal rat.

The morphogenesis of acino-tubular structures and cytodifferentiation of acinar cells in developing rat parotid glands from the day of birth to the 7th day after birth were studied by conventional ultrathin-section electron microscopy in conjunction with freeze replica and space tracer methods. An ultrathin-section study indicated that the acinar cells developed sequentially in the order of the following three stages: (1) the stage of undifferentiated cell immediately after birth, in which the presumptive acinar cells showed very scanty cell cytoplasm, poorly developed organellae, and no distinctive cellular polarity; (2) the stage about the 3rd day after birth, in which cells were arranged into a single layer, resulting in the establishment of three recognizable domains in the plasma membranes, and developing cellular organellae started to distribute with distinctive polarity; and (3) the stage of the 5th day after birth and thereafter, in which secretory granules were formed, indicating the beginning of exocrine functions. Freeze replica and a tracer study demonstrated that the formation of a sealing strand of tight junctional belt took place in correspondence to the establishment of cellular polarity. These results indicated that the development of cellular polarity, plasma membrane domains, tight junctions, and acino-tubular structure were closely interrelated to each other, and preceded the onset of secretory functions.

The effect of ventricular conduction velocity on ST-segment level in acute myocardial ischemia.

The ECG changes in acute myocardial ischemia was studied with ST segment map pattern. Three isolated coronary perfused and isovolumetric contracting canine heart preparations were used. In each preparation, large and small sized acute ischemia was induced by 5 min occlusion of proximal and distal portion of left circumflex coronary artery. Single exponential relationship was seen between R wave amplitude and ventricular activation time (VAT) in normal and in coronary occlusion. The marked degree of delayed VAT induced lowering in R-wave amplitude. Prolongation of VAT, increasing in R-wave amplitude and ST segment elevation was shown at ischemic area. The maximum change in VAT and in R-wave amplitude was seen at center of ischemic zone. The ST segment map pattern was similar with solid angle distribution pattern, despite the slight disturbance of conduction velocity, however, marked delay over 45 msec VAT induced extremely difference of ST map from solid angle distribution map.