By the use of a phase contrast microscope, the author examined the structure of fresh memb-ranous labyrinth of guinea pig. Observations were summarised as fallows: 1) The inner and outer hair cells and their supporting cells were respectively separated from Organ of Corti by means of micro-surgical technique, and their fine structures were observed. 2) The bassilar, reticular, tectorial and Reissner's membarnes and vascular stria were respectively separated from cochlear canal. Their constructions were observed. 3) Particularly, hairs of sensory cells were examined in detail. It might be stated from this observation that the forms and distribution of hairs are different in respective portions of the spiral turn of cochlea. The anthor concluded from the mor phological observation described above, that the hairs of sensory cells play an important role in the analytic mechanism of sound frequency in the inner ear.
Studies on the relation of the duration and pressure of vibration for tuning-ford Cc was not the same relation on the duration and pressure of vibration, and special features of each tuning-fork was different at each body. Efficiency of AMIS or 49-A audiometers bone conduction recievers was not the same standard on the pressure.
In the first place, the author discussed the problem of the test tone in the group audiometry and from the data we obtained it was concluded that the test tone in the screening purpose must be the pure tone (the higher in frequency the better) and not the speech. Then we reviewed the previously reported pure tone group audiometry methods. Their advantages and shortcomings were discussed and we found that the most important failure in the previously reported methods were in the way of response. Based upon these considerations we suggest a new method of pure tone group hearing test. This is a method of using a "Receiver-Push button-Signal lump" system (using 40 receivers, push buttons and signal lumps). Lastly we compared the so-called group hearing test and the individual screening test and concluded that at least for two reasons (i. e. test time and examiner's effort), the former is better than the latter.
Changes of cochlear response (C. R.) in the guinea-pig with the powerful sound stinmli were observed using the automatic ink-writing-levelmeter. (1) In the early stage of the stimulation, the response started to decrease rapidly. The level of the response became constant in about 10 seconds. (2) Transition of potential to test tone after the removal of the stimuli was observed. Rate of the diminution was most remarkable in a moment of removal of stimulating tone, and then the response begin to recover. In the beginning, the recoverry was most rapid, but soon slowed down gradually reaching to the. original level after a period of reconvalescence. (3) When the stimulus was stronger or duration of stimulation was longer, the rate of dimin-ution was larger and recovery period was longer. (4) When the duration of stimulation was prolonged at same rate, effect of this prolongation was more remarkable in the case stimulated with loud tone, than in the case stimulated with weak tone. (5) In a moment of the removal of stimulus, the rate of diminution of response to still tone (testing tone) was more remarkable than response to londer tone (stimulatingtone). (6) These recovery-curves of C. R. was similar to the fatigue recovery-curves of the human-audition.
In purpose to study the central mechanism of nystagmus, the author destroyed the cerebrum, the cerebellum, and brain-stem separately. or combinedly in rabbits. Observations of results were mainly directed on the spontaneous nystagmus and directional preponderance. The author designated as directional preponderance (DP) when nystagmus elicited easily to one side without spontaneous nystagmus. When the nystagmus to one side was predoni-nantly seen after the spontaneous nystagmus, it was designated similarly as DP. As a method to evaluate DP, the caloric test, alternate hot and cold test (10°C 10cc: 55°C 20cc) was used. The localization of the injury was confirmed by histological examination. The results obtained were summerized as follows: 1) As the responsible site for the vestibular DP, temporal area in the cerebrum, medulla of cerebellar hemisphere, paraflocculus, cerebellar nuclei in the cerebellum were observed. When the unilateral vestibular nuclei was destructed, DP to the operated side or to the sound side were obs-erved. By histological examination of the former case, a slight injury, in the latter case, a diffuse destruction of Deiter's nuclei were shown. 2) By cutting the brachium pontis, DP to the non-operated side was observed. It may be said that the cortico-ponto-cerebellar tract is regarded as the most important pathway in the nystagmus controlling circuit. 3) In the nystagmus controlling circuits, the pathway, for example, left cerebral cortex (temporal area)→right brachium pontis→right cerebellar cortex→medulla of cerebellar hemisphere, parafloccu-lus→right nucl. dentatus→right old cerebellar nuclei→left vestibular nuclei was considerd as the most important circuit. And when the inhibition of the higher centers to the lower centers in this circuit were checked, the DP may be elicited as the results of the unbalance in the bilatelar vestibular system. 4) There were four types in the DP phenomenon. In Type 1, Type 2, Type 3, the duration of nystagmus to one side was prolonged, in Type 4 the duration of nystagmus to one side was dimi-nished, and the duration to another side was prolonged. 5) The DP is more markedly influeuced by the cerebellum rather than by the cerebrum.
The anatomical resemblance of the submaxillary gland to other pneumatized cavities such as the mastoid cells and the lung in fetal stage has led us to be interested in. their pathological resemblance study. Thus a series of experiments were conducted to study pathogenesis of ectasia in the excretory duct of the salivary gland, using as background our proved experimental knowl-edge on pathogenesis of bronchiectasis interpreted by pneumatization theory. At first, relationship between the salivary glands and other pneumatized cavities was studied by morphological comparison of the structure of the excretory duct and alveoli of the submaxill-ary gland with that of the mastoid cells, bronchial tree and pulmonary alveoli. Then 36 dogs underwent two types of surgery, ligation of glandular lobule en masse on one group and ligation of excretory duct at its base on the other before they were observed from 2nd to 120th postopera-tive day mainly on atrophy, regeneration and dilatation of the glandular alveoli and proliferation of the excretory duct. The result was carefully checked on the surgical specimen of the subma-xillary glands of chronic inflammation before following information was obtained. 1. Result of the lobular ligation In the early experiments dilatation of the excretory duct and proliferation of the duct wall associated with diminuction of its lumen are seen proximally to the line of ligation. In the distal area the excretory duct underwent irregular cystic dilatation and degeneration, even partial necrosis. In the four month old experiments, dilatation and proliferation of proximal part of the duct beco-mes distinct associated with merging of alveoli into a large cavity and now formation of excretory ducts in its vicinity. In the distal side of the ligation the duct wall becomes thin with increased cystic dilatation and marked alveoli are organized into connective tissues holding irregular regene-rated or enlarged alveoli. 2. Resilt of the ductal ligation The excretory ducts reveal marked dilatation with thin wall and atrophied and detached epit-helium. These changes resemble to those in the distal duct of the lobular ligation group. Attention should be directed to the fact that dilataton of the duct takes place in the first group not only in the distal part but also in the proximal part if the ligation, coinciding with our finding in the experimental study on pathogenesis of bronchiectasis. Therefore, the obstruction of gland-ular lumen must be the main cause of salivary gland ectasia among which distal dilatation of the lobular ligation group and cystic dilatation of the ductal ligation group are easily explained as the obstructive ectasia. The proxymal dilatation, however, must be interpreted by pneumatization theory as a manifestation of dynamic energy potentiality which is inborn to the excretory ducts and glandular alveoli as to anyy other pneumatized cavity. Regeneration and dilatation of the sali-vary gland alveoli have been confirmed experimentally in this study although less significantly than in the pulmonary alveoli.
The authors study concerned the relationship of counter-rolling in human eyes to vestibular function. For this study a modification of Nagels instrument consisting of a headband, a celluloid plate for measurement of the dislocation, and an axis that conjugates the headband and celluloid plate was used to measure the angle of dislocation of Mariottes' blind spot. This modification of Nagels' instrument can move with the angle of examinees' head, thus obtaining a more accurate measurement. A total of 53 individuals were examined during this study. Of this total 36 were without complaint and 17 had symptoms of vestibular disorder. The results of this study are as follows: If r is the value of the counter rolled angle of the right eye when the head was declined from 60° right to 60° left and l is the value of the left eye, the following rule will apply. (1) In normals and individuals with bilateral vestibular disorder: 0≤|r-l/r+l|≤0.15 (2) In unilateral disorders: 0.16≤|r-l/r+l|≤1.00 The ballance in relation to muscle tonus is equal in normals and those affected bilaterally. In unilateral disorders the ballance in relation to muscle tonus is remarkably affected.
The behavior of the mucous membrane of the turbinal in chronic sinusitis is not well known. I have planned to investigate the relationship between the histological ehanges of the turbinal and that of the sinus mucosa as a part of the pneumatization study in our institut. I have observed histologically the mucous membrane of the maxillary sinus and the ipsilateral inferior turbinal in 100 cases and that of the ethmoidal sinus and the turbinal in 43 cases. The results are as follows: 1) The histological changes of the turbinal were classified into three main types, namely edema-tous, infiltrative and fibrous types, after the classification of the mucosa in chronic sinusitis. 2) The mucous membrane of the inferior turbinal revealed mostly a edematouscehanges in chronic sinusitis of the edematous type and a fibrous changes in that of the fibrous type. 3) The changes of the middle turbinal was similar to that of the inferior turbinal, but the ede-matous type has higher incidence in the middle turbinal than in the inferior turbinal. 4) The edematous changes of the mucous membrane was seen more frequently in the sinus me-mbrane than in the turbinal membrane. 5) From the forgoing results the author assumes that the change of the mucous membrane of the turbinal would be influenced by the local constitution such as the sinus membrane, thus having some relation to pneumatization of the sinus. 6) The author had studied the microscopical findings of the turbinal membrane, with particular attention to the cavernous, bodies whose magnified models were reconstructed after numerous mic-roscopical photographs. It is believed that the muscular procces in the cavernous body is not a inflammatory product, but a physiological unit contributing to the contraction of the cavernous body.
Clinical and histological observation of the postoperative paranasal cysts was made. The con-clusion was as follows: 1) In the clinical and statistical observation in 120 cases such as patiant's age, sex, affected side and duration, the results were almost as same as those have been reported. 2) In the treatment, recurrence is prevented by making two large communications between the cyst and the nasal cavity through the middle and lower nasal meatus, in spite of the traditional operation in which the cyst is removed completely. 3) In the pathological and histological studies, mucous epithelium, most of which was ciliated, was observed in 14 out of 17 cases including some multilocular cysts. 4) In the microscopic observation of the basement membrane, it is apparently recognized that the membrane consists of thin basement membrane and membraneous hyaline layer secondarily pro-duced. The layer, therefore, existed in verious forms and was observed in about 40 per cent of all the cases. The epithelium was all ciliated 5) The, assumption about the pathogenesis of the cyst obtained by the operation and the path-ological and histological studies is that; the cyst, i. e. the retention cyst, develops from small inde-ntation of the sinus bone, which remain with mucous membrane after the operation. Considerring the above fact, therefore, it is quite effective to make Communication between the cyst and the nasal cavity as a method of treatment.
Surgical observations were carried on 555 cases who had had the operation of the paranasal sinus via maxillary sinus and also had the sphenoid sinus opened. As for the locations of sphenoid sinus when there is an eminence on the basal surface of the ethmoidal sinus, the sphenoid sinus is located just under the eminence; and when there is an eminence adjacent to the posterior margin of the middle nasal concha, it is located on the medial side of the eminence. The shape of the sinus can be classified into six groups. There are some, though a few in number, who present only a trace of the sinus and also some whose sinus is lacking entirely. As for the feature of the basal surface of the ethmoidal sinus adjacent to sphenoid sinus during the-operation, about half the number observed presents the eminence on the surface, followed by those-showing a recess on the surface, and those showing a plane surface are least. When the sphenoid sinus is visible through the basal surface of the ethmoid sinus in bluish color, the sphenoid sinus is located at the medio-inferior side of the basal surface. Looking at the inner surface of sphenoid sinus, its wall presents a white and smooth aspect. When a suction tube can be easily inserted into a cavity through superior nasal meatus after pressing the middle nasal concha useing a long bladed speculum, the cavity can generally be consi-dered as the sphenoid sinus. As for the complications of the sphenoid operation 4 cases of injury to the dura mater, 3 cases of orbital disturbances, and 9 cases of hemorrhage from the sphenopalatine artery were observed. As for the pathological changes in the mucous membrane of sphenoid sinus, x-ray photograph taken, preoperatively utilizing Proetz displacement method used to give us a reliable suggestion on it. If the sinus is filled with 20% moljodol solution by Proetz method, it may be considered the pathological changes in the mucous membrane are slight.
A survey on the hearing impairment in a group of female loom attendants, investigations on the effectiveness of the use of ear plugs in prevention of such impairment, and auditory fatigue-test for the female workers were carried out and the following results were obtained. 1) Hearing impairments appeared in the female loom attendants in the third month of the work as dip-type high frequency hearing impairments with peaks in 4000cps-5000cps range. At the end of the sixth month the impairment reconered a little, but in one year it again tended to become worse in proportion to the number of working years. However, in all cases, hearing impairments in the speech frequency range were not observed. 2) Experiments on the insulation capacity of ear plugs were carried out. It was found that ear plugs attenuate noise in the high frequency range (over 2000cps) for about 30db. It was also found that loom attendants who wore ear plugs were almost completely free from hearing impair-ments at the end of one year. It was found, however, that further improvement in the appearance and material of the ear plugs was necessary. 3) Comparing hearing capacity of the workers before and after the 8 hours work it was found that the loom noise affected hearing particularly in 4000cps-5000cps range. Auditory fatigue-tests also showed many cases with prolonged recovery time after 8 hours work. 4) Although it was not possible to mark those workers who would be highly susceptible to hea-ring impairment at the time of employment only with auditory fatigue-test, it was found that those with remarkably prolonged recovery time were more liable.
The author reported 12 cases of the so-called family streptomycin deafness, i. e. the family in which two or more deaf persons with hearing disorders due to the use of streptomycin were found, and following observations were performed: (1) Thirty-six persons in 12 families were examined, and in which 22 cases were exam ned audiologically. (2) In 36 cases, 4 cases were not streptemycin deafness, but the chronic progressive labyryn-thine deafness. (3) Previously, the author recognized that the individual differences in the occurence of stre-ptomycin deafness due to at least the inherent vulnelability of the hearing organ itself. (4) As the fact upon which this assumption were based, the author previously stated the indi-vidual differences in the occurence, progress and prognosis of the disease, symmetrical audiogram and family appearence, etc. (5) Now the author add one remark to it, that is a fact that in the same family we can find chronic progressive labyrinthine deafness and also streptomycin deafness at the same time. As the conclusion of this observation and consideration, the author maintain the inherent vul-nelability of the ear as the most important factor in the etiology of streptomycin deafness.
After the stepping test with eyes covered had been done according to the original method, i. e. with the head in normal upright position, the same procedure of stepping was repeated with the head prone, supine, inclined to the left and inclined to the right respectively. As exemplified by representative cases shown in figures, the majority of cases of Meniere's disease showed marked deviation in stepping in a certain constant direction and this phenomenon was apt to be especially marked when the head was inclined to the side of the impaired ear verified with tinnitus and difficulty of hearing. In cases which had positional vertigo subjectively but no manifest positional nystagmus objectively, the stepping test revealed the fact that the angle of deviation was largest and ataxia was seen during stepping when the head took such a position as could induce positional vertigo. By means of this new test, latent abnormality of the labyrinthine function in cases of Meniere's disease was manifested in higher incidence than the usual tests of vestibulo-spinal reaction.
Only 10 cases of reticulum cell sarcoma arising from paranasal sinuses have been reported in Japan. A 56 years old female developed reticulum cell sarcoma a woman arising from ethmoidal cells, and infiltration to nasal cavity and maxillary sinus was observed. For the purpose of an extensive exhaustive removal of the tumor leaving smallest scar possible, partical resection of the nasal bone and the maxillary bone was done. The patient is recovered from the surgery and irradiation of Co60 was given.
The vestibular nuclei play an important role in the vestibular nystagmus, but many obscure problems have been remaind about them. The author carried out the- experiment with rabbits, and observed the influence of higher center (temporal area, paraflocculus) to the nystagmus induced by destruction of vestibular nuclei. Spontaneous nystagmus and directional preponderance (D. P.). were carefully obserued during tha exteriuent. D. P. was determined by alternative hot and cold test. The localization of the injury was confirmed by histological examination. The results obtained were summarised as follow: 1) In case of horizontal nystagmus after destruction of vestibular nuclear area, the injuries were seen chiefly in Deiter's nuclei and lateral part of medial longitudinal fasciculus. It was estimated that they were connected with horizontal nystagmus but it was difficult to find the constant relation between the other types of nystagmus and vestibular nuclei. 2) There are three types-of D. P. when the spontaneous nystagmus disappeared after desfruction of vestibular nuclei, D. P. to the operated side, D. P. to the non-operated side and thesec no D. P. 3) Although the cases showing D. P. to the operated side were never influenced by injury of temporal area, but they were influenced by injury of paraflocculus. 4) D. P. to the operated side observed after destruction of vestibular nuclei were more easily influenced by the central lesion than D. P. to the nonoperated side. 5) In regarding to inhibition of higher center to the vestibular nuclei, paraflocculus acted much stronger than temporal area.