A human middle ear consists of an eardrum and three ossicles which are linked by each other, and connect with the eardrum and an inner ear. The inner ear consists of a cochlea and a vestibular system. An abnormality o...A human middle ear consists of an eardrum and three ossicles which are linked by each other, and connect with the eardrum and an inner ear. The inner ear consists of a cochlea and a vestibular system. An abnormality of the human middle ear such as ossicular dislocation may cause conductive hearing loss. The conductive hearing loss is generally treated by surgery using artificial ossicles. The treatments of conductive hearing loss require a better understanding of characteristics and dynamic behaviors of the human middle ear when the sounds transmit from outer inner to inner ear. The purpose of this research is to simulate the dynamic behaviors of a human ear system comprising the middle ear and the cochlea in the inner ear using the finite element method (FEM). Firstly, the eigen-value analysis was performed to obtain the natural frequencies and vibration modes of the total ear system. Secondly, the frequency response analysis was carried out. Thirdly, the time history response analyses were performed using human voices as the external forces. In the time history response analyses, the sounds created as input sound pressures were used. Human voices, for example vowels “I”, “u” and “e” as input sound pressures were created by using the sound pressures downloaded from the opening samples of human voices as wav files in a website. Then it was clarified that the high frequency components of sounds are reduced by the middle ear system.展开更多
Conclusion: Early-stage detection of temporal bone carcinoma improves the survival rate. When detected at an advanced stage, predicted prognosis is poor even with a combination of surgery, radiotherapy and chemotherap...Conclusion: Early-stage detection of temporal bone carcinoma improves the survival rate. When detected at an advanced stage, predicted prognosis is poor even with a combination of surgery, radiotherapy and chemotherapy. Objectives: We evaluated treatment strategies and survival rates in cases of carcinomas of the external and middle ear. Method: Retrospective review of patients treated at Ehime University Hospital during the 32 years from 1977 to 2008. Subjects were 41 patients, consisting of 21 men and 20 women with a mean age of 63.2 years. Modified Pittsburgh staging system: stage I in 11 cases (27%), stage II in 4 (10%), stage III in 6 (15%) and stage IV in 20 (49%). Histopathology: squamous cell carcinoma (SCC) in 35 cases, adenoid cystic carcinoma (ACC) in 3, and adenocarcinoma (AC) in 3. Thirty-eight patients were treated by surgery. Radiation was added postoperatively in 23 patients. Three patients were treated by chemoradiotherapy. Results: The survival rate of carcinomas detected at an advanced stage was poor with a disease-specific 5-year survival rate of 100% in early-stage disease (stage I and II) versus 20.8% in stage III and 27.5% in stage IV disease, irrespective of histopathology of the tumor.展开更多
文摘A human middle ear consists of an eardrum and three ossicles which are linked by each other, and connect with the eardrum and an inner ear. The inner ear consists of a cochlea and a vestibular system. An abnormality of the human middle ear such as ossicular dislocation may cause conductive hearing loss. The conductive hearing loss is generally treated by surgery using artificial ossicles. The treatments of conductive hearing loss require a better understanding of characteristics and dynamic behaviors of the human middle ear when the sounds transmit from outer inner to inner ear. The purpose of this research is to simulate the dynamic behaviors of a human ear system comprising the middle ear and the cochlea in the inner ear using the finite element method (FEM). Firstly, the eigen-value analysis was performed to obtain the natural frequencies and vibration modes of the total ear system. Secondly, the frequency response analysis was carried out. Thirdly, the time history response analyses were performed using human voices as the external forces. In the time history response analyses, the sounds created as input sound pressures were used. Human voices, for example vowels “I”, “u” and “e” as input sound pressures were created by using the sound pressures downloaded from the opening samples of human voices as wav files in a website. Then it was clarified that the high frequency components of sounds are reduced by the middle ear system.
文摘Conclusion: Early-stage detection of temporal bone carcinoma improves the survival rate. When detected at an advanced stage, predicted prognosis is poor even with a combination of surgery, radiotherapy and chemotherapy. Objectives: We evaluated treatment strategies and survival rates in cases of carcinomas of the external and middle ear. Method: Retrospective review of patients treated at Ehime University Hospital during the 32 years from 1977 to 2008. Subjects were 41 patients, consisting of 21 men and 20 women with a mean age of 63.2 years. Modified Pittsburgh staging system: stage I in 11 cases (27%), stage II in 4 (10%), stage III in 6 (15%) and stage IV in 20 (49%). Histopathology: squamous cell carcinoma (SCC) in 35 cases, adenoid cystic carcinoma (ACC) in 3, and adenocarcinoma (AC) in 3. Thirty-eight patients were treated by surgery. Radiation was added postoperatively in 23 patients. Three patients were treated by chemoradiotherapy. Results: The survival rate of carcinomas detected at an advanced stage was poor with a disease-specific 5-year survival rate of 100% in early-stage disease (stage I and II) versus 20.8% in stage III and 27.5% in stage IV disease, irrespective of histopathology of the tumor.
