Yasushi Koide

Vulnerability of the Organ of Corti in Poisoning

The direct effects of some toxic drugs (kanamycin, dihydrostreptomycin, chloramphenicol, and quinine) upon the organ of Corti have been observed in the guinea pigs. The drug was injected into the middle ear cavity and subsequently reached the organ of Corti through the round window membrane. After several days, the inner ear was taken out and stained with the reagents for succinic dehydrogenase or DPN diaphorase, which were introduced into the tympanic scala through the round window. The following results were obtained:1. Loss of the enzymes was more apparent in the cells witli higher metabolic activities, such as the outer hair cells or the nerve endings.2. Patterns of damage to the organ of Corti seemed to be almost identical. But a smaller difference between antibiotic poisoning and quinine poisoning was found.Generally, it seemed to be possible that higher metabolic activities of the outer hair cells are responsible for weakness of the cells in pathologic processes in the ear.Die unmittelbaren Wirkung...

Distribution of Some Oxidizing Enzymes in the Cochlea

The cochlear specimens prepared by the freezing-method may be subjected successfully to the precise histochemical examination on the distribution of succinic dehydrogenase and/or DPN-diaphorase. The following results were obtained by this method.1. Concentration of both enzymes of both the stria vascularis and lower portions of the spiral ligament is larger in the lower turns than in the higher turns.2. There are no differences in the enzymic activities of the organ of Corti between each turn.

VIII Some Oxidizing Enzymes in the Cochlea

According to our experience, it is difficult to prepare the complete specimen of the cochlear tissues, especially of the organ of Corti. The blue color due to the formation of indophenal blue is very unstable and disappears rapidly when the colored specimen is immersed in an acid solution, such as fixative or decalcifying solution. Therefore, these conditions make it difficult to observe the precise

Biochemical Problems of Inner Ear Disease

The present investigations have revealed that vestibular asymmetry is closely related to the imbalance of glucose contents of perilymph between the bilateral ears. As a result, it is supposed that the vestibular function is influenced by the vascular conditions within the inner ear. This result is sure to be a clue to the understanding of Menieres disease, including its recurrence and the Tullio phenomenon.Since oxygen tension in the inner ear also decreases during intense sound stimulation, disturbances in the vascular system or subsequent oxygen deprivation in the inner ear appear to be the important etiological factors in the onset of some inner ear diseases.In these cases, the biochemical lesions of the inner ear are classified as follows: (1) oxygen deprivation; (2) inhibition of oxidative phosphorylation. It was indicated experimentally and clinically that the combined use of ATP and DPN is markedly effective in inner ear disease.

VIII Indications for Tympanoplasty in an Ear with Antibiotic Resistant Infection

The work of Wullstein and Z611ner -3.6 in the practical application of the technique of tympanoplasty has stimulated otologists throughout the world to become interested in this phase of plastic surgery. Now, most surgeons believe it is worthwhile to try a tympanoplasty. However, the pathological conditions encountered in the surgery, the method and extent of removal, and the details of the reconstruction are so variable that it is most difficult to even approach standardization such as is possible in fenestration or mobilization surgery. So the problem of indications for tympanoplasty seems to remain unsolved. Some of the results were acoustically poor although good results were frequent enough to assure us that this surgery is here to stay.

LXXXIV Foreign Materials in Tympanoplasty

There are primarily five different types of plastic operations on the middle ear. The first is called myringoplasty, in whch an attempt is made at plastic closure of perforation of the tympanic membrane without disturbing the auditory ossicles. The rest of the operations are included under the common name of tympanoplasty. These all involve a radical approach with eradication of active disease of the cell system of the ear and creation of different types of middle ear cavities.

Modified Techniques for surgical Treatment of Large Ranula

The upper part of the sac of cyst was exposed from the overlying tisse us and opening the cavity and treating it with crystal violet were done.The cystic walls exposed were holded in block by a hemostat to facilitate to retract the cyst to any side. And the tissues around the sac were push away against it, not touching the sac itself. Then complete removing ranula could be done successfully.

Experiences with Mastoid Musculoplasty

In the report on a procedure utilizing pedicle muscle flaps to obliterate the large mastoid cavity, direct visual and histological evidence is proved, which the muscle flaps become degenerated and finally absorbed. But the new posterior canal wall could be preserved even after the muscle flaps were absorbed.In all the cases included in the present check-up the final results are satisfactory, since all ears are dry and well epithelized within the time of observation.