<strong>Aim:</strong> Chronic otitis media (COM) is chronic muco purulent discharge through a perforated tympanic membrane. Theossicular chain damage is found in both mucosal and squamosal types of COM. We...<strong>Aim:</strong> Chronic otitis media (COM) is chronic muco purulent discharge through a perforated tympanic membrane. Theossicular chain damage is found in both mucosal and squamosal types of COM. We aim to evaluate relationship between preoperative otologic features, pure tone audiometric findings and intraoperative ossicular chain status in patients with chronic otitis media. <strong>Material and Methods:</strong> 100 patients of either sex aged between 12 to 60 years operated for active or inactive, squamosal or mucosal chronic otitis media attending Ram Lal Eye and ENT Hospital, Government Medical College Amritsar were taken. The preoperative ossicular chain status based on set parameters was compared with the intraoperative ossicular chain status. <strong>Results:</strong> The ossicular chain integrity is more commonly compromised in squamosal COM and the most common ossicle eroded is Incus. Pure tone audiogram has got a very important role in determining the ossicular chain integrity preoperatively and must be done in all cases with accuracy. <strong>Conclusion:</strong> It is concluded that on the basis of otoscopic examination and pure tone audiometry values, we can accurately classify the COM as mucosal or squamosal type and get an idea of the ossicular chain integrity preoperatively hence planning the extent of surgery.展开更多
Aim: To assess the hearing status of the study subjects in terms of degree and type of hearing loss, and establish the burden of this disability in the society. Materials and methods: This is a prospective study condu...Aim: To assess the hearing status of the study subjects in terms of degree and type of hearing loss, and establish the burden of this disability in the society. Materials and methods: This is a prospective study conducted in patients who attend our OPD. After an otorhinolaryngeal examination, all the patients were subjected to pure tone audiometry using MAICA-MA52 audiometer. Results: Our study comprises 1012 males (64%) and 563 females (36%). Out of this, about 15% have conductive deafness and 42% have sensorineural hearing loss. About 29% suffer from mild hearing loss, 26% moderate and 11% severe hearing loss. The alarming information is that about 5% have total hearing loss of Sudden Sensorineural type (SSNHL). Conclusion: Pure tone audiometry is cost effective and easy to perform. Early diagnosis and timely intervention will reduce the morbidity of deafness in our country. Hence it is necessary to identify and treat sudden sensorineural hearing loss and noise induced hearing loss at an early stage.展开更多
Background Blood oxygen level dependent functional magnetic resonance imaging （fMRI） and magnetoencephalography are new techniques of brain functional imaging which can provide the information of excitation of neuro...Background Blood oxygen level dependent functional magnetic resonance imaging （fMRI） and magnetoencephalography are new techniques of brain functional imaging which can provide the information of excitation of neurons by measure the changes of hemodynamics and electrophysiological data of local brain tissue. The purpose of this study was to study functional brain areas evoked by pure tones in healthy and sensorineural hearing loss subjects with these techniques and to compare the differences between the two groups. Methods Thirty healthy and 30 sensorineural hearing loss subjects were included in this study. In fMRI, block-design paradigm was used. During the active epoch the participants listened to 1000 Hz, sound pressure level 140 dB pure tones at duration 500 ms, interstimulus interval 1000 ms, which presented continuously via a magnetic resonance-compatible audio system. None stimulus was executed in control epoch. In magnetoencephalography study, every subject received stimuli of 1000 Hz tone bursts delivered to the bilateral ear at duration 8 ms, interstimulus intervals 1000 ms. Sound pressure level in healthy subjects was 30 dB; in sensorineural hearing loss subjects was 20 dB above everyone＇ s hearing threshold respectively. All subjects were examined with 306-channel whole-scalp neuromagnetometer. Results In fMRI, all subjects showed significant activations in bilateral Heschl＇s gyri, anterior pole of planum temporale, planum temporale, precentral gyri, postcentral gyri, supramarginal gyri, superior temporal gyri, inferior frontal gyri, occipital lobes and cerebellums. The healthy subjects had more intensive activation in bilateral Heschl＇s gyri, anterior pole of planum temporale, inferior frontal gyri, left superior temporal gyri and right planum temporale than the hearing loss subjects. But in precentral gyri, postcentral gyri and occipital lobes, the activation is more intensive in the hearing loss subjects. In magnetoencephalography study, both in the hearing loss and the healthy subjects, the most evident audio evoked fields activated by pure tone were N100m, which located precisely on the Heschl＇s gyrus. Compared with the hearing loss subjects, N100m of the healthy subjects was stronger and had longer latencies in right hemisphere. Conclusions Under proper pure tone stimulus the activation of auditory cortex can be elicited both in the healthy and the sensorineural hearing loss subjects. Either at objective equivalent stimuli or at subjectively perceived equivalent stimuli, the auditory responses were more intensive in healthy subjects than hearing loss subjects. The tone stimuli were processed in a network in human brain and there was an intrinsic relation between the auditory and visual cortex. Blood oxygen level dependent fMRI and magnetoencephalography could reinforce each other.展开更多
It′s generally believed that the appropriate stimuli for sound field tests are warble tones and narrow band noise, while pure tone can only be a signal used in the free field and earphone listening conditions. In thi...It′s generally believed that the appropriate stimuli for sound field tests are warble tones and narrow band noise, while pure tone can only be a signal used in the free field and earphone listening conditions. In this study, we take a measurement of sound pressure distribution, sound field variability, and effects of frequency shifting on sound pressure levels (SPLs) at reference points of pure tone in an audiometric test room. It was found that the pure tone SPLs were also distributed uniformly at some sound field areas although it was not so well as warble tones. This indicated that the test results were relatively stable to head movement and/or frequency shifting in those regions, which was confirmed by the clinical measurements on 20 subjects with severe sensorineural hearing loss. Our study concluded that pure tones could also be suitable for sound field audiometry if subjects were seated at a proper location on the basis of the sound field calibrations.展开更多
文摘<strong>Aim:</strong> Chronic otitis media (COM) is chronic muco purulent discharge through a perforated tympanic membrane. Theossicular chain damage is found in both mucosal and squamosal types of COM. We aim to evaluate relationship between preoperative otologic features, pure tone audiometric findings and intraoperative ossicular chain status in patients with chronic otitis media. <strong>Material and Methods:</strong> 100 patients of either sex aged between 12 to 60 years operated for active or inactive, squamosal or mucosal chronic otitis media attending Ram Lal Eye and ENT Hospital, Government Medical College Amritsar were taken. The preoperative ossicular chain status based on set parameters was compared with the intraoperative ossicular chain status. <strong>Results:</strong> The ossicular chain integrity is more commonly compromised in squamosal COM and the most common ossicle eroded is Incus. Pure tone audiogram has got a very important role in determining the ossicular chain integrity preoperatively and must be done in all cases with accuracy. <strong>Conclusion:</strong> It is concluded that on the basis of otoscopic examination and pure tone audiometry values, we can accurately classify the COM as mucosal or squamosal type and get an idea of the ossicular chain integrity preoperatively hence planning the extent of surgery.
文摘Aim: To assess the hearing status of the study subjects in terms of degree and type of hearing loss, and establish the burden of this disability in the society. Materials and methods: This is a prospective study conducted in patients who attend our OPD. After an otorhinolaryngeal examination, all the patients were subjected to pure tone audiometry using MAICA-MA52 audiometer. Results: Our study comprises 1012 males (64%) and 563 females (36%). Out of this, about 15% have conductive deafness and 42% have sensorineural hearing loss. About 29% suffer from mild hearing loss, 26% moderate and 11% severe hearing loss. The alarming information is that about 5% have total hearing loss of Sudden Sensorineural type (SSNHL). Conclusion: Pure tone audiometry is cost effective and easy to perform. Early diagnosis and timely intervention will reduce the morbidity of deafness in our country. Hence it is necessary to identify and treat sudden sensorineural hearing loss and noise induced hearing loss at an early stage.
文摘Background Blood oxygen level dependent functional magnetic resonance imaging （fMRI） and magnetoencephalography are new techniques of brain functional imaging which can provide the information of excitation of neurons by measure the changes of hemodynamics and electrophysiological data of local brain tissue. The purpose of this study was to study functional brain areas evoked by pure tones in healthy and sensorineural hearing loss subjects with these techniques and to compare the differences between the two groups. Methods Thirty healthy and 30 sensorineural hearing loss subjects were included in this study. In fMRI, block-design paradigm was used. During the active epoch the participants listened to 1000 Hz, sound pressure level 140 dB pure tones at duration 500 ms, interstimulus interval 1000 ms, which presented continuously via a magnetic resonance-compatible audio system. None stimulus was executed in control epoch. In magnetoencephalography study, every subject received stimuli of 1000 Hz tone bursts delivered to the bilateral ear at duration 8 ms, interstimulus intervals 1000 ms. Sound pressure level in healthy subjects was 30 dB; in sensorineural hearing loss subjects was 20 dB above everyone＇ s hearing threshold respectively. All subjects were examined with 306-channel whole-scalp neuromagnetometer. Results In fMRI, all subjects showed significant activations in bilateral Heschl＇s gyri, anterior pole of planum temporale, planum temporale, precentral gyri, postcentral gyri, supramarginal gyri, superior temporal gyri, inferior frontal gyri, occipital lobes and cerebellums. The healthy subjects had more intensive activation in bilateral Heschl＇s gyri, anterior pole of planum temporale, inferior frontal gyri, left superior temporal gyri and right planum temporale than the hearing loss subjects. But in precentral gyri, postcentral gyri and occipital lobes, the activation is more intensive in the hearing loss subjects. In magnetoencephalography study, both in the hearing loss and the healthy subjects, the most evident audio evoked fields activated by pure tone were N100m, which located precisely on the Heschl＇s gyrus. Compared with the hearing loss subjects, N100m of the healthy subjects was stronger and had longer latencies in right hemisphere. Conclusions Under proper pure tone stimulus the activation of auditory cortex can be elicited both in the healthy and the sensorineural hearing loss subjects. Either at objective equivalent stimuli or at subjectively perceived equivalent stimuli, the auditory responses were more intensive in healthy subjects than hearing loss subjects. The tone stimuli were processed in a network in human brain and there was an intrinsic relation between the auditory and visual cortex. Blood oxygen level dependent fMRI and magnetoencephalography could reinforce each other.
文摘It′s generally believed that the appropriate stimuli for sound field tests are warble tones and narrow band noise, while pure tone can only be a signal used in the free field and earphone listening conditions. In this study, we take a measurement of sound pressure distribution, sound field variability, and effects of frequency shifting on sound pressure levels (SPLs) at reference points of pure tone in an audiometric test room. It was found that the pure tone SPLs were also distributed uniformly at some sound field areas although it was not so well as warble tones. This indicated that the test results were relatively stable to head movement and/or frequency shifting in those regions, which was confirmed by the clinical measurements on 20 subjects with severe sensorineural hearing loss. Our study concluded that pure tones could also be suitable for sound field audiometry if subjects were seated at a proper location on the basis of the sound field calibrations.
文摘目的探讨短纯音刺激皮层听觉诱发电位(cortical auditory evoked potentials,CAEP)对听力评估的价值。方法受试者为听力正常成人19例(36耳),感音神经性聋成人患者21例(21耳),以500、1000、2000和4000 Hz短纯音作为刺激声,在醒觉状态下颅顶电极记录CAEP的N1-P2复合波,分析N1-P2阈值与纯音听阈的相关性,以及两者差值在不同人群中的差异。结果所有受试者四个测试频率的N1-P2阈值与对应频率纯音听阈值的相关系数依次为0.971、0.967、0.958、0.955,呈显著的线性相关;听力正常组36耳500、1000、2000和4000 Hz的N1-P2阈值上限(95%置信区间)依次为32、27、32、39 dB SPL,即正常人阈值上限为32.5 dB SPL;正常人N1-P2阈值与纯音听阈的差值依次为18.9±6.1、11.6±5.9、13.3±7.0、18.7±8.3 dB;感音神经性聋患者两者差值依次为10.3±6.0、6.8±8.9、6.5±9.5、12.9±11.4 dB,四个测试频率的差值在两组人群中的差异均有统计学意义(P<0.05)。结论听力正常人短纯音CAEP的N1-P2平均阈值小于32.5 dB SPL;N1-P2阈值与对应频率纯音听阈相关性非常好,听力评估中使用N1-P2阈值预测听力时应注意刺激声的校准及校正值的使用。
