2006 Fiscal Year Final Research Report Summary
Pathophysiology and Treatment Strategy of the Intractable Patulous Eustachian Tube
Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||Tohoku University |
KOBAYASHI Toshimitu Tohoku University, Graduate School of Medicine, Professor -> 東北大学, 大学院医学系研究科, 教授 (80133958)
KAWASE Tetsuaki Tohoku University, Graduate School of Medicine, Associate Professor, 大学院医学系研究科, 助教授 (50169728)
YOSHIDA Naohiro Tohoku University, Graduate School of Medicine, Lecturer, 大学院医学系研究科, 非常勤講師 (90291260)
OSHIMA Takeshi Tohoku University, Graduate School of Medicine, Associate Professor, 大学院医学系研究科, 助教授 (40241608)
WADA Hitoshi Tohoku University, Graduate School of Engineering, Professor, 大学院医学系研究科, 教授 (30111264)
SUZUKI Yoiti Research institute of electrical communiation, Professor, 電気通信研究所, 教授 (20143034)
|Project Period (FY)
2005 – 2006
|Keywords||patulous Eustachian tube / insufficient closure / Valsalva maneuver / CT in the sitting position / cholesteatoma / hemodialysis / sniffing habit / hearing acuity|
Epidemiological study regarding the patulous Eustachian tube was conducted, including the cases due to the hemodialysis. This study revealed that 13 out of 147 cases (8.8%) underwent hemodialysis suffered from patulous Eustachian symptoms shortly after hemodialysis. This is the first report on the relationship of hemodialysis and patulous Eustachian tube.
The diagnosis of the patulous Eustachian tube by the 3D-CT in the sitting position was developed and investigated as to the optimal imaging technique to delineate the patulous tube. It became clear that the method is a useful tool for the diagnosis of the patulous Eustachian tube, especially under performance of the Valsalva maneuver with over 80% accuracy.
The effect of hearing acuity upon the severity of the symptoms of patulous Eustachian tube was evaluated. It was concluded that the presence of hearing loss due to such causes as perforated eardrum, otosclerosis, cholesteatomas, etc., tended to alleviate the symptoms. However, once these conditions were cured by surgeries or other conservative treatments, and hearing improvement was obtained, the symptoms due to patulous Eustachian tube recurred. We proposed to call this condition as latent patulous Eustachian tube.
We examined 171 cases of cholesteatomas to know whether above-mentioned mechanism is operational in cholesteatoma cases. About 30% of the cholesteatoma cases were found to have sniffing habit induced by patulous Eustachian tube. When the hearing acuity was compared between the cases with sniffing habit and without it, the group with sniffing habit was found to have better hearing; indicating the mechanism mentioned in 3 was operational.
In addition, the cases in which sniffing habit was continued after surgery had better hearing acuity. This result indicated that the continuation or cessation of sniffing depends in major portion to the hearing acuity after surgery on the cholesteatoma (Hasegawa J, et al.)
Research Products (4 results)