1998 Fiscal Year Final Research Report Summary
Gas exchange via the mucosa in the middle ear cleft -comparative study of normal ears and inflamed ears-
| Project/Area Number |
08671954
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Otorhinolaryngology
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| Research Institution | Niigata University |
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Principal Investigator |
NONOMURA Naobumi Niigata University, School of Medicine, Associate Professor, 医学部, 助教授 (00156217)
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| Co-Investigator(Kenkyū-buntansha) |
IKARASHI Fumio The Nippon Dental University, School of Dentistry at Niigata, Professor, 新潟歯学部, 教授 (30176060)
TAKAHASHI Sugata Niigata University, School of Medicine, Professor, 医学部, 教授 (10154824)
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| Project Period (FY) |
1996 – 1998
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| Keywords | middle ear cleft / gas exchange / mucosa / normal ear / inflamed ear |
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| Research Abstract |
Experimental study : Using the normal middle ear of the pig, the relationship between the respiratory condition and middle ear pressure was examined. The partial pressure of carbon dioxide in the venous blood and the middle ear pressure were decreased by hyperventilation, and increased by hypoventilation. These findings suggest that bidirectional gas exchange induced by gas diffusion between the middle ear cleft and capillaries in the submucosal connective tissue acts in the normal middle ear. The capacity of gas exchange via the mucosa was also examined in the inflamed ear. Inflammation was induced in the middle ear cleft of the pig and the same experiment in the normal ear was conducted. In some cases, the middle ear pressure changed according to the respiratory condition as in normal ears, whereas in some cases, no apparent change in the middle ear pressure was observed, Based on histological study and quantitative analysis by histomorphometry, it was revealed that gas exchange via the mucosa was impaired by middle ear inflammation, and the degree of impairment was directly proportional to the ratio of the diseased mucosa in the residual middle ear air cell system.
Clinical study : In subjects with normal middle ears, the middle ear pressure was measured while the hyperventilation and hypoventilation was repeated in the supine position. As in the experimental study, the partial pressure of carbon dioxide in the venous blood and the middle ear pressure were decreased by hyperventilation, and increased by hypoventilation, These findings suggest that bidirectional gas exchange acts in the normal human middle ear as well. Gas exchange via the mucosa was examined in the ear exhibited mild otitis media with effusion with type C_2 tympanogram. The findings showed that the capacity of gas exchange via the mucosa was not impaired in the mild otitis media with effusion.
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Research Products
(12 results)
