The fact that auditory stimuli elicited an evoked potential in the efferent activity of the recurrent laryngeal nerve was reported in the cat, and this reflex action was termed the “auditory laryngeal reflex”. In the present study, it was reported that a comparable auditory laryngeal reflex action was experimentally identified in the rabbit. Moreover, the relationships between the intensity of the auditory laryngeal reflex action and the following parameters of sound stimuli: sound pressure; sound frequency: and the pattern of sound stimuli (train and single of tone burst) were described. Furthermore, the effects of the depth of anesthesia using thiamylal or urethan and chloralose on the reflex action were studied. The experiments were performed on rabbits anesthetized with diethyl ether, paralyzed with pancronium bromide and artificially ventilated under monitoring of the end-tidal CO2 levels. Biphasic evokcd potential in the recurrent laryngeal nerve was identified of the averaging computation with 500 times triggered by sound stimuli. The first deflection of the evoked potential was positive, and the second one was negative. The peak time of the first peak was 12-14 msec. and that of the second was 20-23 msec. Within a range around the threshold of the evoked potential in response to sound stimului as measured by the sound pressure, both the amplitude of each of the biphasic evoked potential depended on the intensity of sound stimuli. The threshold of the evoked potential was about 25 dB higher than that of the auditory brain stem response (ABR) recorded at the same time. Comparable biphasic evoked potential as induced by the sound stimuli with frequencies ranging from 250 Hz to 8 kHz. Continuous sound stimuli of a tone burst (3 kHz; 110 dB; duration of tone, 5 msec.; interstimulus interval 238 msec.) for 20 minutes did not result in any distinct change of the waveform of the evoked potential, and no adaptation to the sound stimuli was noticed. Intravenous administration of thiamylal (4 mg/ kg) abolished the evoked potential due to the auditory laryngeal reflex and depressed concurrently the spontaneous nerve activity of the recurrent laryngeal nerve. As the anesthesic level become less, the abolished reflex action as well as the depressed spontaneous nerve activity gradually recovered. Power spectral analysis of the recurrent laryngeal nerve activity revealed two spectral peak of 75 Hz and 110 Hz. These components were identified to be analogous to those described as the “high frequency oscillations” in the phrenic nerve activity in the rabbits. The sound stimuli (3 kHz, 110 dB, tone burst, duration of tone 5 msec., interstimulus interval 238 msec.) did not exert any significant influence on the respiratory modulation of the nerve activity and the activity of the high frequency oscillations in the recurrent laryngeal nerve. The administration of chloralose at a dose of 50 mg/kg reduced and at higher doses abolished the two spectral peaks representing the high frequency oscillations in the order of the first spectral peak at 75 Hz and then that at 110 Hz. The shortness of the latency of the evoked potential in the recurrent laryngeal nerve suggested that the auditory laryngeal reflex was mediated by certain neural organizations in the brain stem. It was concluded that the auditory laryngeal reflex may play a significant role as an important component in the auditory phonatory feedback system subserving speech and singing in man.
Using growing rabbits, the septal cartilage was resected either simply without any other treatment or with insertion of autograft, incision, or destruction, and observations were made for development of cartilage regeneration or septal deviation following the operation. Simple resection was performed for the following seven sites: upper, middle, lower, anterior and posterior areas as well as extended areas (lower end is either conserved or resected). Following simple resection, cartilage regeneration starts from about 1 week after the operation corresponding to the site of resection, with regenerated cartilage filling all the area at 4 week, if the perichondrium is conserved. Septal deviation after simple resection begins to appear in association with cartilage regeneration, and it almost completes at 8 weeks after resection. Incidences of septal deviation as classified by resection site in animals fed for 8 and 16 weeks were 7/11 cases (63.6%) for the upper area, 2/8 cases (25%) for the middle area, 2/4 cases (50%) for the lower area, 3/5 cases (60%) for the anterior area, 4/6 cases (66.7%) for the posterior area, 6/8 cases (75%) for the extended area with conservation of the lower end and 0/4 cases (0%) for the extended area with resection of the lower end. Thus, the incidence of septal deviation was lowest after resection of the middle site. Results obtained after insertion of autograft were compared with findings of adult rabbits. In growing animals union between the existing cartilage and the gafted cartilage was seen from the early stage, while in adults rabbits no such findings were obtained. It is considered that septal deviation occurs due to imbalance caused by difference in cartilage stroma between existing cartilage and grafted cartilage as well as the presence or absence of an increasing tendency. It appears more remarkably in growing rabbits (3/3 cases or 100%) than in adult animals (4/8 cases or 50%). Animals incised of the cartilage showed no change with growth similar to that observed in control animals. In animals with destruction, regenerated cartilage appeared evenly from the left and right perichondrium with the destructed cartilage fragment as the center, showing no septal deviation was seen. As the possible mode of cartilage regeneration, the following three are considered according to the septal condition. A: Cartilage is regenerated continuously from the perichondrium B: Cartilage is regenerated as if the area surrounded by cartilage and perichondrium is filled with cartilage inducing substances. C: Cartilage is regenerated by cartilage inducing substance in an island shape in the area with sparse connective tissue. In this case the regenerated cartilage well reproduces the condition before resection.
The purpose of this study was to make pathohistological examination on the tympanic membrane of OME (otitis media with effusion) patients as well as to classify the degeneration of tympanic membrane lamina propria into 4 stages. Especially, observation was made on the degenerating process mainly of inner and outer fiber layers of pars tensa and of submucosal connective tissue by optical microscope and electronic microscope. The objects of observation were the OME tympanic membrance which did not show any improvement after 3 months' preservative treatment. When the ventilation tube was inserted (and left alone) through the tympanic membrance under a general anesthesia, the tympanic membrance of size approximately 1 mm × 2 mm was taken as a sample specimen from the anterior inferior quadrant. Control specimens were taken from the tympanic membranes of 28-week conceptus and 3-month old infant who died of sickness. The specimens thus obtained were doublefixed by 2% glutaraldehyde solution and 1% osmium tetroxicide, and after specific dehydration with a series of ascending concentration of ethanol, they were embedded in Epon-Araldite resin and sectioned into slices. In case of optical microscope, observation was made after executing toluidine blue dyeing to the specimens. In case of electronic microscope, uranium lead acetate dyeing, or when necessary, tannic acid dyeing was executed to the specimen. We used electronic microscope JEM 1200 EX made by Nihon Denshi (JEOL). With the execution to toluidine blue dyeing in case of optical microscope, it was possible to clearly observe the outer and inner fiber layers. As a result of observation by optical and electronic microscope, we obtained the following conclusions. (1) Histological degeneration in tympanic membrane of otitis media with effusion were most conspicuously observed in inner and outer fiber layers and in submucosal connective tissue. (2) Hypertrophy of tympanic membrance of otitis media with effusion increased along with the continuation of inflammation. The reasons of it should attributable to the edema between tissues and proliferation of submucosal connective tissue resulting from the inflammation. The proliferated fibroblasts in the submucosal connective tissue were observed as to a stratified formation layers. However, inner and outer fiber layers disappeared along with the advancement of otitis media with effusion. (3) The tympanic membrane of otitis media with effusion which was not medically treated eventually showed a state of contabescence. That is because the inner and outer fiber layers had almost completely disappeared and the submucosal connective tissues formed cicatrices. (4) The largest factor which relates with the degeneration, destruction and disappearance of lamina propria of tympanic membrance is considered to be edema resulting from the inflammation. The edema dynamically separates and severs the fibrils which constitutes the edema itself. There is a possibility that the fluid between tissues contains collagen dissolving enzyme, which prompts the separation of the fibers. (5) It was suggested that in the process of degeneration of fiber bundle, the finer fibrils out of two kinds of fibers which compose the fiber bundle had disappeared in the early stages, but the reason of it was not clear. (6) It was suggested that in the degenerating process of inner and outer layers, the inner fiber layers had disappeared in the earlier stages. (7) With sespect to the degeneration in tympanic membrance, we propose the case stage classification as follows: Stage I: Coexistence of inner and outer fiber layers is observed. Stage II: Outer fiber layer is observed but inner fiber layer is disappeared. Stage III: A greater part of outer fiber layer is disappeared. Stage IV: Both layers ire disappeared and replaced with connective tissue.
Rhinomanometry was executed for cases of nose and sinus disease under several conditions using the anterior method. Then application of rhinomanometry to routine clinical examination formed the subject of my study. Though the rhinomanometry is considered to be useful as an objective indication for nasal obstruction and the standardization of measuring method has so far progressed, we cannot safely say that full use has been made for general clinical tests, the reasons of which might be: (1) Methods of measurement and expression have not been completely unified; (2) Usefulness of rhinomanometry in routine clinical examination has not been clarified sufficiently; (3) How to consider the congestion and decongestion of nasal mucosa remains unknown. In order to deliberate such problematical points as above we made the following studies. I. With a variety of nose and sinus diseases (90 cases) as subjects, 1 carried out the rhinomanometry before and after adrenalin spraying on nasal mucosa. As an expression method of rhinomanometry we used nasal resistanc and effective cross-sectional area (ECSA) and revealed the advantages and disadvantages of these two. Further we observed if there be any difference of decongestion of nasal mucosa between cases of respective diseases. Moreover we studied the relationship between the ECSA after adrenalin spraying and that after operation. II. With 269 cases suspected of allergic rhinitis as the subjects, I worked out rhinomanometry when judging the results of provocation test. The reference for positive swelling of nasal mucosa was studied through two expression methods of nasal resistance and ECSA. Then I discussed the usefulness of combined use of rhinomanometry for judging the results of provoccation test. In addition, possible influences of age on the results of provocation test and nasal patency were studied. III. In order to examine nasal cycle in cases of sinusitis, we observed the time-evolutive rhinomanometry with cases having lesions on hemilateral sinus as the subjects. The reason why I chose the hemilateral sinusitis is that I considered I could clarify the relationship between inflammation and nasal cycle by comparison on both sides of diseased and healthy. The results I could obtain are follows: (1) For judging the change of congestion and decongestion of nasal mucosa, expression by ECSA was more suited than that by nasal resistance. (2) For decongestion of nasal mucosa by adrenalin spraying into nasal cavity, a tendency to large was recognized in allergic rhinitis, but there was no significant difference between respective disease. (3) ECSA after operation revealed a strong positive correlation with that after adrenalin spraying before operation. (4) Combined use of rhinomanometry in judging the results of provocation test could reduce the false negative and increase the testing sensitivity. (5) It has turned out a tendency that the ECSA increase with age, while the change of ECSA by provocation revealed decreasing trend with age. In particular for 60 years or more of age, there were many caces where ECSA does not change by provocation test through the patient complained of allergic rhinitis. (6) In the 2 hours' rhinomanometry with hemilteral sinusitis as subjects, nasal cycle was recognized in 47% of chronic sinustis cases and 73% of acute sinusitis cases. (7) The amplitude of the change in nasal resistance and ECSA by nasal cycle was larger in the acute sinusitis. In the acute sinusitis this tend was remarkable only on sick side, where the percentage was high of the cases in which swelling of nasal mucosa on sick side was larger in duration and degree than on the opposite side. Rhinomanometry is useful for clinical examination. But for the correct judging, we must be careful with the problematical points as above.
Epistaxis is encountered rather frequently in daily practices. Bleeding from Kiesselbach's area has long been the title of many studies. However, many points remain unelucidated concerning bleeding from the posterior area of the nasal cavity. In the present study epistaxis from infraturbinal posterior end was investigated variously by clinical statistical analysis and roentgonography using contrast medium. Moreover, the infraturbinal posterior end was studied using vascular mold preparation and skull of the carcass, and running of arteries in this area was investigated histologically. Following results were obtained: 1. It was postulated that the arteries which are responsible for epistaxis around the infraturbinal posterior end are the sphenopalatine artery and the descending palatine artery (in particular the major palatine artery). 2. In the lateral posterior nasal branch of the sphenoplatine artery, there was a site where the blood vessel considerably approaches the mucosa similar to the Kiesselbach's area. After departing from the spheno-platine foramen the lateral posterior nasal branch showed vascular structure different from that before it leaves that foramen. There was a site where the thickness of the tunica media became not constant and the adventitia was in direct contact with the internal elastic plate. In addition, about 10 mm posterior to the infratubinal posterior end, there was a site where adipose tissue of the surrounding area is scanty and the border between the adventitia and the surrounding connective tissue is not obvious. It was assumed that blood vessel is broken relatively easily through external force to the blood vessel and intravascular pressure. 3. The bone defect of the internal wall of the major palatine artery was found in as high as about 28% of cases. In this area, arteries are considerably approximating to the submucosa. Therefore, it is postulated that blood vessels of this area are relatively easily broken by external force to the blood vessel and intravascular pressure.