No abstract available.
Bone Conduction* ; Tympanoplasty*

Bone Conduction ; Hearing Aids ; Humans

Bone Conduction ; Hearing Aids ; Humans

No abstract available.
Bone Conduction* ; Otitis Media* ; Otitis*

To evaluate the effect of mastoidectomy and posterior tympanotomy on postoperative hearing, 101 cases of type I tympanoplasty operated by one operator were retrospectively reviewed. The patients were divided into three groups; Group I(N=14) was the type I tympanoplasty without mastoidectomy ; Group II(N=44) was the type I tympanoplasty with simple mastoidectomy ; Group III(N=43) was the type I tympanoplasty and mastoidectomy with posterior tympanotomy. The type of operation was determined by preoperative physical finding, radiological findings, and decision was finally made during the operation. Preoperative mean air-bone gaps of pure tone average were significantly different among three groups(group I;13 dBHL; group II ; 22 dBHL, group III ; 31 dBHL). There was no significant difference of the postoperative air-bone gap gains at speech frequencies among three groups and the average gain was about 9 dBHL at 3 months, 11 dBHL at 6 months. respectively. However, the postoperative hearing was significantly changed according to the types of operation in the air and bone conduction, specially in the high tone area. At the 4 kHz, postoperative bone conduction did not changed significantly in the group I and II, however, postopearive bone conduction significantly worsened from 14 dBHL to 20-22 dBHL in the group III. In the same time, air conduction at 8 kHz was significantly aggravated from 52 dBHL to 65 dBHL postoperatively in the group III.
Bone Conduction ; Hearing* ; Humans ; Retrospective Studies ; Tympanoplasty

No abstract available.
Bone Conduction* ; Ear, Middle* ; Otitis Media* ; Otitis* ; Pathology* ; Temporal Bone*

This study was performed to evaluate the effects on hearing of video tape manufacturing workers exposed to organic solvents. The experimental groups included solvents exposed group 51 and unexposed group 57 workers. All workers was examined air and bone conduction sensitivity by pure tone audiometer. The mean age of solvents exposed group was 34.1 and nonexposed group was 35.8. The mean duration of solvents exposed group was 7.3years. High frequency hearing loss prevalence of both groups was 23.5% in the group exposed to organic solvents and 17.5% in nonexposed group. There is no statistical significants in the prevalence of high frequency hearing loss. According to comparison of mean auditory threshold value by frequencies, on the air conduction test, right was statistically significant in the 250, 500, 1000, 2000, 4000Hz, except 8000Hz. Left 250, 500, 1000Hz was statistically significant. On the bone conduction test, left250, both 500, 1000, 2000, 4000Hz, except right 250Hz, was statistically significant difference. Generally, auditory sensitivity threshold of the exposed group was higher than the nonexposed group.
Auditory Threshold ; Bone Conduction ; Hearing Loss ; Hearing* ; Prevalence ; Solvents*

BACKGROUND AND OBJECTIVES: A free-beam-type CO₂ laser, which use a micromanipulator mounted on a microscope as the delivery system, has the merit of not being affected by hand tremor at the time of shooting. However, this delivery system has several disadvantages, including a restricted operation range and a risk of incorrect focusing. A fiber-type CO₂ laser uses a hand-held delivery system and has the opposite merits and demerits. We compared the results of stapes surgery with free-beam and fiber type delivery systems. SUBJECTS AND METHODS: The study enrolled 36 patients who underwent stapedotomy with free-beam- (n=26) or fiber- (n=10) type CO₂ lasers. The air-bone (AB) gap closure, bone conduction (BC) change, and operating time were evaluated. The AB gap closure was calculated by subtracting the preoperative BC thresholds from the postoperative air conduction thresholds. The BC change was calculated by subtracting the postoperative BC thresholds from the preoperative BC thresholds. RESULTS: The mean operating time was significantly (p=0.035) shorter in the fiber-type group (72.5±8.2 min) than in the free-beam-type group (80.5±11.4 min). The mean AB gap closure did not differ significantly (p=0.297) between the free-beamand fiber-type groups (5.8±10.1 and 1.4±6.8 dB, respectively). The mean BC change did not differ significantly (p=0.873) between the free-beam- and fiber-type groups (2.4±6.9 and 2.8±5.3 dB, respectively). The hearing outcomes did not differ significantly between the two groups. CONCLUSIONS: Operating times were significantly shorter using the fiber-type CO₂ laser, while hearing outcomes did not differ significantly between the two groups.
Bone Conduction ; Hand ; Hearing ; Humans ; Otosclerosis ; Stapes Surgery* ; Stapes* ; Tremor

BACKGROUND AND OBJECTIVES: The reports of normative measurements for inner ear structure using computer-based programs are rare. The purpose of this study was to measure the normative data of the Korean inner ear structures and establish the basic data for diagnosis of congenital inner ear anomaly. SUBJECTS AND METHOD: Temporal bone CT of 38 patients (16 men and 22 women) without apparent disease of middle and inner ear, fractures or major disorder such as seizure or tumor were retrospectively reviewed. Fifteen dimensions on axial views and 9 dimensions on coronal views were measured in PACS using pi-view program. The slice thickness of CT was 0.6 mm. RESULTS: From the axial view, the canal diameter of SSCC was 1.09+/-0.15 mm, the bony island width was 5.70+/-0.50 mm, the bony island width of LSCC was 3.99+/-0.58 mm, the cochlear upper turn width & height were each 5.63+/-1.07 and 3.03+/-0.65 mm. The vestibular aqueduct were observed 95.3%. From the coronal view, the cochlear height was 5.14+/-0.36 mm. The length of IAC was significantly longer in male than female (p<0.05) and the opening site of IAC was significantly wider in the left than the right (p<0.05). The upper turn of cochlea in good bone conduction (< or =10 B) had larger width and smaller height than those in poor bone conduction (>10 dB). CONCLUSION: We established the Korean normative measurements of the inner ear structures, which can be used for further diagnosis of the inner ear anomaly.
Bone Conduction ; Cochlea ; Diagnosis ; Ear, Inner* ; Female ; Humans ; Male ; Retrospective Studies ; Seizures ; Temporal Bone* ; Vestibular Aqueduct

BACKGROUND AND OBJECTIVES: The masking should be used in pure tone audiometry when the difference between the air-conduction threshold of the tested ear and the bone-conduction threshold of the non-tested ear is more than interaural attenuation (IA). But the standardized average value of IA in Korean has not been evaluated until now. The purpose of this study is to evaluate the interaural attenuation in Korean population. SUBJECTS AND METHODS: Of the patients who visited our department from March, 2007 to August, 2009, 44 patients were selected who had unilateral severe sensorineural hearing loss or deafness and contralateral normal hearing. When the difference between air-conduction threshold with and without masking was more than 10 dB, the interaural attenuation at each frequency was obtained by subtracting the contralateral bone conduction from the air-conduction threshold without masking. RESULTS: The interaural attenuations at each frequency were 45-75 dB (250 Hz), 50-75 dB (500 Hz), 40-75 dB (1 kHz), 45-85 dB (2 kHz), 50-90 dB (4 kHz). 77.2% of the subjects showed interaural attenuation of 55-65 dB at 250 Hz, and 80.9% in 50-60 dB at 500 Hz, 79.5% in 55-65 dB at 1 kHz, 83.4% in 45-60 dB at 2 kHz, and 76.4% in 50-65 dB at 4 kHz. Most of the patients were distributed 15-25 dB higher than the minimal interaural attenuation at 1 kHz. At 2 kHz and 4 kHz, most of the patients were distributed around 15 dB of the minimal interaural attenuation. CONCLUSIONS: These results can be used as reference values for masking of pure tone audiometry. But, further studies with large population should be done to get more precise results and contributing factors to IA values.
Audiometry ; Bone Conduction ; Deafness ; Ear ; Hearing ; Hearing Loss, Sensorineural ; Humans ; Masks ; Reference Values