岡山医学会 Acta Medica Okayama 0030-1558 67 3-4 1955 電気災害に因る聽器病変の実験的研究 731 748 EN Masuo Uetsuka There has been certain basic investigations taken on the auditory disorders caused by weak electric current, by such scholars as Runge, Oda and Wittmaack; but little has been done toward the experimental study on the same caused by electric disaster. A) Employing guinea-pigs, I applied. D. C. 100V. 100 M. A. -250 M. A. from 30 seconds to 10 minutes. D. C. 70.000-110.000V. 4 M. A. -100M. A. 10 seconds to 10 minutes. A. C. 110V. 250 M. A. 2 minutes. A. C. 220V. 450 M. A. from 20 seconds to 30 seconds. on their auditory organ, and these guinea-pigs were killed immediately after the experiment for vital fixation. 1) D. C. Experiment. Cells of spiralganglion and vestibularganglion, maculae acusticae, as well as crista have appeared to have been swollen on anode, while on cathode, they looked in a state of shrinkage. 2) A. C. Experiment. In the cells of spiralganglion and vestibularganglion, one part of them showed swelling while the other part showed a shrinkage and these opposite findings existed in mixed form. B) In order to know the influence of Joule's heat produced by this experiment, I have conducted a heated test using "diathermy" without catching any such histological changes mentioned above. C) Having fed a guinea-pig that has undergone these electroshock for a long time and pursuing its histoloigcal changes, could discover otitis media in all cases; while labyrinthitis in 2/3 cases. As to one third cases where labyrinthitis could not be detected, no change happened to their maculae acusticae, crista, or cells of vestibular-ganglion. D) Next, a test has been performed using rabbit. D. C. 100V. 400 M. A. 20 seconds-40 seconds. D. C. 110.000V. 4 M. A. 10 minutes-40 minutes. The histological changes seen in those cases which have suffered vital fixation immediately after the experiment, have proved as the same with those observed in guinea-pig test. A devastation of cells of spiral ganglion on anode was noticed in a rabbit that underwent a vital fixation 60 days after having been administered D. C. 110.000V. 4 M. A. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 67 3-4 1955 人体に於ける電気災害に由る聽器障碍例に就て 749 751 EN Masuo Uetsuka There are two types in human auditory disturbances owing to electric disasters, one of which is what one may call immediate injury, appearing on the heel of those disasters; the other, used to appear days or months after disaster, and often spoken of as after injury. The author have had chance to take a survey of 4 cases that suffered violent electric disaster. 1) 65 years-old male; has become victim to A. C. 300V. immediately after the event, felt right-ear tinnitus, slight vertigo and tendency to fall down on the right side. Though he could recover in a few days from symptoms, a tinnitus as well as difficult-hearing of right ear began a year afterward. By examination, it has been proved that his right ear had a marked auditory disability in the area higher than c(2) and complete deaf at c(6). 2) 50 years-old male; experienced 4 electric shocks, i. e., A. C. 3.300V. 3 times; A. C. 60.000V. once. In every time, he felt an obstruction feeling of ear, tinnitus, as well as vertigo after the disaster. These symptoms disappeared spontaneously in a few days, and at present he enjoys normal hearing. 3) 20 years-old male; struck with A. C. 3.300V. No otologic symptoms felt after the accident. At present, his hearing is normal. 4) 28 years-old male; struck with A. C. 3.300V. No sensible diorder happened. At present, normal hearing. Cases 1) and 2) may be said as immediate injuries due to electric disaster, and Case 1) may be considered to have induced after injury besides. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 67 3-4 1955 電流作用の迷路に於ける侵襲部位決定に関する生理学的実験 753 757 EN Masuo Uetsuka As to the shock caused by the electric current toward the ear, it has been clarified, by Oda, Wittmaack, Minami as well as myself, that there appear certain different histological changes on maculae acustica at either anode or cathode. From this, one could imagine that positive as well as negative electric current give certain stimulus quite contradictory toward maculae acustica. Then, if certain electric stimulus of same pole and same intensity are administered to both the ears simultaneously, one might surmise that certain utterly different stimulus (control or excite) would be given on both maculae acustica, under either positive or negative current. If any rotatory stimulus is added (which is a pure stimulus for the maculae acustica), it may be supposed that pictures contrary to each other might appear in its compensatory eye deviation, according to the kind of current which is either positive or negaive. Having activated 2 M. A. same pole current on a rabbit's both ears (laying indifferent electrode on the back) I fixed it on the rotatory table invented by Hoeve and de Kleyn and photographed rotatory eye deviation. Unluckily, in my experiment, I failed to recognize any difference in the eye deviation between positive or negative current. However, as I thought the method to be interesting, I have recorded it duly. No potential conflict of interest relevant to this article was reported.