This paper analyzes the shortcomings of the existing pure tone audiometers, and proposes a system to realize pure tone audiometry and speech audiometry with a new DSP processor. The pure tone test signal produced by the system has accurate frequency, high signal-to-noise ratio, and small harmonic distortion. The noise generator that comes with DSP adds a band-pass filter to realize the generation of narrow-band noise. At the same time, due to the modular structure of software design, the system has good ease of use and scalability. The test results show that the hearing test system has excellent performance and can be better used in hearing medical diagnosis.
Audiometry, Pure-Tone/methods* ; Hearing ; Noise ; Signal-To-Noise Ratio

BACKGROUND AND OBJECTIVES: To analyze the 125 Hz pure-tone thresholds in patients with acute low frequency sensorineural hearing loss (LFHL) and to investigate the value of 125 Hz thresholds for the assessment of LFHL. SUBJECTS AND METHOD: Hearing tests including 125 Hz pure-tone were performed in 91 patients with acute LFHL ≤500 Hz and in 46 subjects with normal hearing. Patients with sudden sensorineural hearing loss or Meniere's disease were excluded. Inter-group and intra-group comparison of 125 Hz was made between LFHL and the control groups. RESULTS: There was a significant difference of mean pure-tone thresholds at 125 Hz between the acute LFHL and the normal groups (39.8±8.9 vs. 14.3±6.7 dB). Eight (8.8%) patients in the LFHL group showed normal thresholds at 125 Hz, but all other subjects were normal at 125 Hz in the control group. None with the average hearing thresholds at 250 and 500 Hz ≥40 dB had normal threshold at 125 Hz. There was a significant correlation between 125 Hz and other low frequencies in the LFHL group (250 Hz; r=0.81, 500 Hz; r=0.63). CONCLUSION: Not all patients with acute LFHL show abnormal hearing threshold at 125 Hz although every subject with normal hearing is within the normal limits at 125 Hz. Threshold assessment should be made at 125 Hz when a mild LFHL exists in the conventional pure tone audiometry.
Audiometry ; Audiometry, Pure-Tone ; Auditory Threshold ; Hearing ; Hearing Loss, Sensorineural* ; Hearing Tests ; Humans ; Meniere Disease ; Methods

OBJECTIVE: Tried to find the relationship between tinnitus and each testing method, provided information for objective diagnosis and treatment for tinnitus patients with sensorineural hearing loss. METHOD: The characteristics of audiology tests, including pure tone audiometric, acoustic immittance, middle ear muscle reflexes, matching test, distortion products otoacoustic emission(DPOAE) were compared in 79 ears of 69 tinnitus patients with sensorineural hearing loss. RESULT: The RI positive rate was higher in Convergence curve in tinnitus patients of sensorineural hearing loss, with the rate being 51.3%. The detection rates of DPOAE were 15.2% in patients of sensorineural hearing loss tinnitus groups, which were significant lower than those in control group. CONCLUSION Psychoacoustic techniques can produce a useful amount of clinical data regarding tinnitus in different aspects, these data can help clinicians design needed based managements. DPOAE test is helpful for the diagnosis of lesions in some tinnitus patients.
Audiometry, Pure-Tone ; Hearing Loss, Sensorineural ; complications ; physiopathology ; Hearing Tests ; methods ; Humans ; Otoacoustic Emissions, Spontaneous ; Psychoacoustics ; Tinnitus ; complications ; physiopathology

INTRODUCTIONThe present study aimed to obtain preliminary tympanometric data of young Malay adults and to compare the results between genders.

METHODS96 undergraduate students (49 males and 47 females), aged 19-25 (mean and standard deviation 21.14 +/- 1.31) years, participated in this study. Otoscopic examination, pure tone audiometry, qualitative tympanogram and ipsilateral acoustic reflex were measured to ensure a clear ear canal, normal hearing and normal middle ear function, prior to tympanometric measurement. As a result, a total of 154 ears (80 ears from males and 74 ears from females) were selected for further statistical analyses. The tympanometric parameters measured were peak compensated static acoustic admittance (Peak Y(tm)), tympanometric width (TW) and equivalent ear canal volume (V(ea)).

RESULTSThe results showed that the mean Peak Y(tm), V(ea) and TW for males were 0.81 mmhos, 1.48 cubic cm and 113.67 daPa, respectively. The mean Peak Y(tm), V(ea) and TW for females were 0.63 mmhos, 1.12 cubic cm and 98.04 daPa, respectively. Males were found to have significantly higher mean V(ea) and mean Peak Y(tm) than females. However no significant gender difference was observed in the mean TW.

CONCLUSIONThe current study suggests that young Malay adults may require gender-specific Peak Y(tm) and V(ea) values when implementing a quantitative approach in tympanogram interpretation.

Acoustic Impedance Tests ; methods ; Acoustics ; Audiometry ; methods ; Audiometry, Pure-Tone ; Ear Canal ; pathology ; Ethnic Groups ; Female ; Humans ; Malaysia ; Male ; Otoscopy ; methods ; Reference Values ; Sex Factors ; Young Adult

OBJECTIVE: To compare the hearing test data of the profound hearing-impaired children with the hearing aids and with cochlear implants; to find out the useful method to measure the residual hearing. METHOD: Twenty-two profound hearing-impaired children participated in the study with complete set of hearing test and verbal rehabilitation file. Ten children fitted hearing aids and underwent verbal rehabilitation more than 3 months. Among the other 12 children with cochlear implants, 10 children fell in the same year range with the hearing aid patients. The children with hearing aids were divided into two groups according to the achievement of the verbal rehabilitation. ASSR threshold and pure- tone threshold were compared between the groups. RESULT: (1) ASSR test: 7 children (14 ears) with hearing aids achieved good verbal representation, in which ASSR threshold can be recorded on 2.71 frequency on average [(110.92 +/- 7.43) dB HL]. Among 3 children with hearing aids representing poor verbal achievement and 5 children with additional cochlear implant because of the poor verbal achievement with hearing aids, only 1.06 frequency had response of ASSR test [(110.88 +/- 48.52 ) dB HL]. (2) Pure tone audiometry: the average threshold of the 7 children with good representation was (96.11 +/- 7.81) dB HL, and the threshold on 3 frequency were less than 100 dB HL on average. The average threshold of the other 3 children with poor verbal achievement was (112.19 +/- 5.15) dB HL, and none of the frequency threshold was 100 dB HL. CONCLUSION The number of the frequency with the response of ASSR and the threshold < or =100 dB HL of pure tone audiometry is an effective indication of the useful residual hearing.
Audiometry, Pure-Tone ; methods ; Audiometry, Speech ; methods ; Child, Preschool ; Cochlear Implantation ; Cochlear Implants ; Female ; Hearing Aids ; Hearing Loss, Sensorineural ; physiopathology ; rehabilitation ; Humans ; Infant ; Male ; Retrospective Studies

OBJECTIVEAuditory brainstem responses (ABR) evoked by tone burst is an important method of hearing assessment in referral infants after hearing screening. The present study was to compare the thresholds of tone burst ABR with filter settings of 30 - 1500 Hz and 30 - 3000 Hz at each frequency, figure out the characteristics of ABR thresholds with the two filter settings and the effect of the waveform judgement, so as to select a more optimal frequency specific ABR test parameter.

METHODSThresholds with filter settings of 30 - 1500 Hz and 30 - 3000 Hz in children aged 2 - 33 months were recorded by click, tone burst ABR. A total of 18 patients (8 male/10 female), 22 ears were included.

RESULTSThe thresholds of tone burst ABR with filter settings of 30 - 3000 Hz were higher than that with filter settings of 30 - 1500 Hz. Significant difference was detected for that at 0.5 kHz and 2.0 kHz (t values were 2.238 and 2.217, P < 0.05), no significant difference between the two filter settings was detected at the rest frequencies tone evoked ABR thresholds. The waveform of ABR with filter settings of 30 - 1500 Hz was smoother than that with filter settings of 30 - 3000 Hz at the same stimulus intensity. Response curve of the latter appeared jagged small interfering wave.

CONCLUSIONSThe filter setting of 30 - 1500 Hz may be a more optimal parameter of frequency specific ABR to improve the accuracy of frequency specificity ABR for infants' hearing assessment.

Acoustic Stimulation ; Audiometry, Evoked Response ; Audiometry, Pure-Tone ; methods ; Auditory Threshold ; Child, Preschool ; Evoked Potentials, Auditory, Brain Stem ; Female ; Humans ; Infant ; Male

OBJECTIVE: To evaluate the accuracy with which auditory steady-state response (ASSR), tone burst auditory brain stem response (Tb-ABR) and click-evoked auditory brainstem response (c-ABR) thresholds predict behavioral thresholds, using a within-subjects design. METHOD: ASSR, Tb-ABR and c-ABR thresholds were recorded in a group of adults with normal hearing (58 ears). Evoked-potential thresholds were recorded and compared with behavioral, pure-tone thresholds. RESULT: The results suggested both ASSR and Tb-ABR thresholds had high correlations to pure-tone thresholds. Tb-ABR thresholds were recorded much closer to behavioral threshold than ASSR thresholds. There was a linear relation between c-ABR thresholds and average thresholds of 2 kHz, 4 kHz pure tone audiometry. CONCLUSION Both the ABR and the ASSR provided reasonably accurate predictions of multifrequencies behavioral threshold. Tb-ABR combined with c-ABR may take the accuracy predicted behavioral threshold.
Acoustic Stimulation ; Adolescent ; Adult ; Audiometry, Evoked Response ; methods ; Audiometry, Pure-Tone ; Auditory Threshold ; Evoked Potentials, Auditory, Brain Stem ; physiology ; Humans ; Young Adult

OBJECTIVES: To explore the relationship between the frequency characteristics and response threshold of auditory steady-state response (ASSR), auditory brainstem response (ABR) and 40 Hz auditory event related potential (40 Hz AERP), and their application values in forensic medicine. METHODS: Thirty volunteers with normal hearing (60 ears) were selected to perform pure tone audiometry (PTA) threshold and ASSR, ABR and 40 Hz AERP response threshold tests in the standard sound insulation shielding room, and the results were statistically analyzed by SPSS 22.0 software. RESULTS: At 0.5 kHz and 1.0 kHz frequencies, the correlation between 40 Hz AERP response threshold and PTA threshold was good, which was better than that of ASSR and ABR response threshold. At 2.0 kHz and 4.0 kHz frequencies, the correlation between ASSR and ABR response thresholds and PTA threshold was good, which was better than that of 40 Hz AERP response threshold. CONCLUSIONS To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.
Acoustic Stimulation/methods* ; Audiometry, Evoked Response ; Audiometry, Pure-Tone ; Auditory Threshold/physiology* ; Evoked Potentials, Auditory, Brain Stem/physiology* ; Forensic Medicine ; Hearing/physiology* ; Humans

OBJECTIVE: To investigate the relationship between minimum contralateral masking level (MCML) and pure tone threshold of the masking ears by the same frequency tone masking test. METHODS: The pure tone thresholds of 30 subjects (60 ears) were measured by pure tone audiometry and MCML was obtained by means of the same frequency tone masking test. RESULTS: When the stimulus was at the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-30 dBHL. 82.4 percent of results showed the differences not higher than 10 dBHL, 97.1 percent of results showed the differences not higher than 15 dBHL. When the stimulus was at 10 dBHL above the threshold of masked ears, the differences between MCML and pure tone threshold of masking ears were among 0-35 dBHL. 90.5 percent of results showed the differences not higher than 25 dBHL, 98.1 percent of results showed the differences not higher than 30 dBHL. CONCLUSION The real thresholds can be deduced correctly by the same frequency tone masking test.
Acoustic Stimulation/methods* ; Adult ; Audiometry, Pure-Tone/methods* ; Auditory Perception/physiology* ; Auditory Threshold ; Female ; Forensic Medicine/methods* ; Hearing Tests/methods* ; Humans ; Male ; Perceptual Masking

OBJECTIVETo analyze the short-term and long-term effect of Er-yttrium aluminum garnet (Er-YAG) laser in stapes surgery.

METHODSThere were 86 patients operated by the Er-YAG laser stapedotomy from 2001 to 2007 were analyzed retrospectively, with 23 male, 63 female and 13 double ears and with the average age of 48 years old, ranging from 12 to 78. All of 99 ears suffered deafness of conduction. The average air-bone-gap (ABG) of all patients before surgery was (37.4+/-9.0) dB HL (ranging from 13.7 to 58.7 dB). The patients followed-up over 6 weeks after the surgery was regarded as the short-term result, while over one year follow-up as the long-term effect (according to the standard of the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery). The followed-up average time was (26.3+/-15.8) months (range from 14 to 73 months). The pre-post-operation average bone conduction auditory threshold of 2 kHz and 4 kHz were observed. The data of the patient whether or not has the symptoms of tinnitus and dizzy and the lasted days were also recorded.

RESULTSAfter surgery, short-term ABG of 99 ears was (15.7+/-8.7) dB, matched-pairs t test with the numbers of before surgery, t=22.79, P<0.01. The results of 45 ears (45.5%) with ABG<10 dB or air conduction improved more than 30 dB were regarded as excellence. The air conduction of 88 ears (88.9%) improved more than 15 dB was regarded as utility. With 82 ears (82.8%) followed-up more than 1 year, the average ABG was (11.7+/-6.8) dB, matched-pairs t test with the numbers of before surgery, t=23.37, P<0.01, compared with the short-term visit result [(15.3+/-9.2) dB, 82 ears], t=4.82, P<0.01, both of which were considered statistically extremely significant. Among them, 50 ears (61.0%) have the excellent effect while 74 ears with (90.2%) ABG<20 dB. The average bone conduction auditory threshold in 2 kHz was (34.5+/-15.0) dB before surgery, matched-pairs t test with short-term visit result (33.4+/-15.9) dB, t=1.96, P=0.026 14, with long-term visit result (32.7+/-15.2) dB, t=3.24, P=0.000 87, all of which had the significant difference, manifest that the Cohort's notch had been improved after the surgery. The data of bone conduction auditory threshold of 4 kHz with long-term following-up result matched-pairs t test with that of surgery before, t=0.76 (P>0.05), which showed the change of the bone conduction had no statistics difference. There were 55 ears had the persistent tinnitus before surgery, in which 42 ears (76.4%) with no the tinnitus, 13 ears with same to that of preoperative, and 3 ears (3.0%) with remaining tinnitus after surgery but who had not it preoperation and all disappeared after 2 - 3 days. There were 12 ears (12.1%) with light dizzy after surgery, but their live could deal with himself and the average dizzy lasted 2.3 days.

CONCLUSIONSEr-YAG laser stapes surgery is safe to the inner ear, and it primal free from the imminent risk in stapes surgery, so the effect can be affirmed.

Adolescent ; Adult ; Aged ; Audiometry, Pure-Tone ; Child ; Female ; Follow-Up Studies ; Humans ; Lasers, Solid-State ; Male ; Middle Aged ; Otosclerosis ; surgery ; Retrospective Studies ; Stapes Surgery ; methods ; Young Adult