Long Term Hearing Outcome of Stapedotomy

Chronic subjective tinnitus is a common feature of clinical otosclerosis. Analysis of the records of 1,014 consecutive cases of clinical otosclerosis, all confirmed by stapes surgery in South Australia between 1960 and 1972, gives a preoperative prevalence of this symptom of 65%. The association of tinnitus with various predictors is considered, and a statistical analysis is presented. Tinnitus has an association with gender (p < .0001), mean preoperative bone conduction (BC) level (p = .0012), mean air conduction (AC) level (p = .0192), and mean air-bone gap (p = .0075). The associations between tinnitus and the age of the patient, the duration of deafness, the presence of Schwartze's sign, and the severity of footplate pathological involvement were all nonsignificant. The association of tinnitus with the AC and BC thresholds is unexpectedly paradoxical. An economic predictive model for tinnitus in otosclerosis has been constructed from the 2 strongly significant variables, gender and mean BC hearing level, by logistic regression. In this large series of cases, the log odds in favor of finding tinnitus are about 0.810 for male subjects and 1.394 for female subjects when the BC level is zero. The log odds fall by 0.014 for each decibel of mean BC rise.

ABSTRACTIntroductionTympanic membrane perforation can cause hearing impairment with detrimental effects on communication and quality of life, and is a problem affecting an estimated 250 million people. To date, there is little analysis to inform public policy on options for assistive hearing technology rehabilitation in this group.MethodsWe undertook a systematic review and meta‐analysis of six electronic databases registered with PROSPERO and reported in accordance with PRISMA 2020 standards. The primary outcome was the mean air and bone conduction hearing threshold associated with tympanic perforation.ResultsOf 720 studies identified, 16 contained data for meta‐analysis. Mean air conduction threshold was 48.3 dB HL in adults and 31.9 dB HL in children. Mean bone conduction was 26.6 dB HL in adults and 9.5 dB HL in children. The prediction interval was −1.7 to 46.7 dB HL for bone conduction and 15.0–70.5 dB HL for air conduction.ConclusionsThe majority of adults and children with tympanic perforation have air conduction thresholds within the range of rehabilitation with air conduction hearing aids. The majority also have good sensorineural hearing reserve, meaning bone conduction devices are also suitable. Our analysis can guide the development of affordable technology for the rehabilitation of those with tympanic perforation.

To compare the early postoperative results and late patient-related postoperative results by a Short-Form 36 quality of life survey after conventional haemorrhoidectomy and PPH procedure with additional surgical intervention in noncomplicated, complicated and delayed cases of the disease. The comparison was made between comparable patient groups after conventional haemorrhoidectomy (n = 168) and after PPH with additional surgical intervention (n = 142). The early and late postoperative results and quality of life analysis according to SF-36 questionnaire were compared. The length of procedure was significantly shorter after the PPH procedure (37.4 vs 49.4 min). The amount of postoperative nonopiate analgesics was similar, but consumption of opiates was more in the conventional group. The rate of early postoperative complications was similar. In the PPH group significant improvement in all quality of life parameters was ascertained 6 months after operation, but 6 weeks after surgery several parameters in this group were lower. In the conventional group improvement was ascertained only for several parameters. The significant improvement of quality of life after PPH operations was ascertained especially at a mean period of 6 weeks. The PPH procedure performed in complex cases of the disease and combined with other surgical intervention because of the anorectal comorbidity assures better early postoperative results and better postoperative quality of life in a 6-month follow up in comparison with conventional haemorrhoidectomy. The continuation of quality of life studies with a longer follow up is required concerning Longo operation.

To improve understanding of normal responses in infants by comparing air conduction (AC) and bone conduction (BC) auditory thresholds using both the auditory steady state response (ASSR) and behavioral testing methods in normal-hearing infants (6 to 18 months of age) and adults. At present, there are no correction factors available for estimating BC behavioral thresholds from BC ASSR thresholds, which is a barrier to clinical implementation of the ASSR. In addition, previous studies have reported infant-adult differences in AC and BC sensitivity, which suggest a "maturational" air-bone gap (ABG) that is not attributable to a conductive pathology; no study has yet compared AC and BC thresholds for either ASSR or behavioral methods in the same individuals. The objectives of the present study are: (1) to compare BC thresholds between methods and provide the initial step toward positing correction factors to predict BC behavioral thresholds, (2) to directly compare AC and BC thresholds to provide an accurate estimate of the maturational ABG, (3) to determine preliminary normal levels for BC and AC ASSRs to exponentially amplitude modulated stimuli, and (4) to investigate infant-adult differences in AC and BC thresholds using ASSRs and behavioral assessment tools. Participants were 23 infants (6.5 to 19.0 months of age) and 12 adults (17 to 50 years of age) with normal hearing. Thresholds were estimated at 500, 1000, 2000, and 4000 Hz using air- and bone-conducted stimuli for ASSRs and behavioral testing. The ASSR stimuli were exponential envelope modulated (amplitude modulation [AM]) at modulation frequencies of 78, 85, 93, and 101 Hz for 500, 1000, 2000, and 4000 Hz, respectively, presented simultaneously. Frequency-modulated (warble tone) stimuli were used for behavioral testing for both infants and adults, respectively. All stimuli were calibrated in dB HL. Thresholds were compared across frequency and between stimulus presentation modes, between age groups and assessment method. Normal levels for AC and BC ASSRs to AM stimuli were also calculated. The findings indicated that BC thresholds were, on average, 7 to 16 dB poorer for ASSR compared with visual reinforcement audiometry (VRA), but varied widely across infants. For infants, mean ABGs of 14 to 17 dB were found for low-frequency ASSR thresholds but mean ABGs for VRA thresholds were less than 10 dB. The preliminary normal levels for ASSR AM stimuli at 500, 1000, 2000, and 4000 Hz, respectively, were: (i) AC: 30, 30, 20, and 20 dB HL, and (ii) BC: 20, 20, 30, and 30 dB HL. There was a tendency for infant and adult ASSR thresholds to differ for BC, but not for AC. Behavioral thresholds for AC and BC were similar between infants and adults and across frequency. Infant-adult and AC-BC threshold differences are greater for ASSRs compared with behavioral measures. The results support the presence of a clinically significant maturational ABG in the low frequencies for infant ASSRs but not for VRA. The findings also show a significant offset between BC ASSR and BC VRA thresholds and large intersubject variability.

A clinical protocol for diagnosing hearing loss (HL) in infants designed to meet early intervention guidelines was used with the goals of providing normative data for (1) frequency-specific tone burst auditory brain stem response (TBABR) thresholds by air conduction (AC) and bone conduction (BC) in early infancy used to classify type and severity of HL, (2) ear-specific behavioral thresholds for these same infants by 1 yr of age, and (3) the relationship between TBABR thresholds and behavioral thresholds for this group of infants. AC- and BC-TBABRs were measured in young infants (mean age, <3 mo) under natural sleep to classify the type and severity of HL (conductive, sensorineural, or mixed). A small group of normal-hearing adults undergoing the same TBABR protocol served as a control group. Threshold and latency data for AC- and BC-ABR were analyzed for infants classified as having normal hearing and for those with and without conductive HL. The ability to detect conductive HL based on ABR latencies evoked by clicks presented at 80 dB nHL was assessed. Behavioral thresholds using visual reinforcement audiometry (VRA) were measured in infants at a mean age of approximately 10 mo. The relationship between TBABR and behavioral thresholds obtained in infancy was analyzed, and the prediction of behavioral thresholds from TBABR thresholds was examined. Mean TBABR thresholds in young infants with normal hearing tested under natural sleep were similar to previously published data. The relationship between AC- and BC-TBABR thresholds differed as a function of stimulus frequency for infants but not adults. A mean air-bone gap (ABG) of 15 dB was present at 500 Hz even in normal-hearing infants, with those infants classified as having conductive HL presenting with substantially larger ABGs. Wave V latency functions for AC- and BC-TBABR also differed between infants and adults as a function of frequency. Infant BC-TBABR latencies were well matched between those with normal hearing and conductive HL, whereas AC-TBABR latency functions separated these groups. Mean VRA thresholds using insert phones in normal-hearing infants tested were between 14 and 17 dB HL for all three test frequencies at a mean age of 9.7 mo. Correlations between TBABR and VRA thresholds, both obtained during infancy, were strong for all three test frequencies (r = 0.86, 0.90, and 0.91 for 500, 2000, and 4000 Hz, respectively). AC- and BC-TBABR results can be readily obtained in young infants under natural sleep and were used to classify the type of HL based on the absolute threshold and the size of the ABG. Differences in wave V latency functions for TBABR by AC and BC and wave I and V latencies of the high-level click ABR also distinguish between infants with and without TBABR ABGs. Ear-specific behavioral responses can be obtained at levels under 20 dB HL in normal-hearing infants younger than 1 yr using VRA, and these behavioral thresholds correlate well with TBABR thresholds obtained on average 6.5 mo previously in this population. The current results suggest that protocols for obtaining AC- and BC-TBABR and behavioral thresholds that meet guidelines for early intervention are clinically feasible.

Objective: To evaluate the short-term (postoperative), medium-term (5 years), and long-term (10 and 15 years) audiometric results of patients who underwent stapedotomy and to determine specific factors associated with better postoperative outcomes. Methods: This study is a retrospective case review of 486 ears with surgically confirmed stapes fixation who underwent microscopic small fenestra stapedotomy. Preoperative, postoperative, and medium- and long-term air conduction (AC), bone conduction (BC), and air-bone gap (ABG) were assessed. Postoperative factors associated with better postoperative outcomes were evaluated. Results: At 10- and 15-year follow-ups, ABG, AC, and BC were significantly deteriorated but clinically preserved in comparison with postoperative results. According to a multiple quantile regression, younger age was associated with better postoperative results at 0.25 kHz (p = 0.003) and 4 kHz (p = 0.028) and a smaller preoperative ABG was associated with better audiometric results at 0.25 kHz (p = 0.048), 0.5 kHz (p = 0.001), and 4 kHz (p = 0.001). In addition, younger age (p = 0.001 for AC and p < 0.001 for BC) and preoperative AC PTA (p < 0.001 for AC) were significantly associated with better postoperative AC and BC PTA. Conclusions: Stapedotomy surgery provides short-, medium-, and long-term hearing benefits in our studied cohort. ABG, AC, and BC thresholds obtained after the surgery are clinically preserved in 5-, 10-, and 15-year follow-ups, with an age-expected BC deterioration. Smaller preoperative ABG and younger age were positive predictors for better postoperative ABG. Future research should address long-term subjective and quality of life outcomes.

Relationship between ultra-high-resolution computed tomography score of oval window region involvement and audiometry in otosclerosis.

The aim of this study is to investigate the contribute of the endoscopic exclusive transcanalar approach for the management of stapes malformations. A retrospective chart review was made at our tertiary referral centers. 17 patients with stapes malformations underwent surgery with endoscopic exclusive transcanal approach. A complete audiological and radiological assessment before and after surgery was performed. 12/17 (70%) underwent a surgical endoscopic correction, In case of fixed platina underwent five endoscopic stapedotomy and one endoscopic stapedectomy were performed. In case of mobile platina five endoscopic ossiculoplasties with partial ossiculoplasty replacement prosthesis were performed, 3 with autologous remodeling incus and 2 with malleus head remodeling. In 1 case, only an endoscopic stapes mobilization was made. In 5/17 (30%), due to difficult anatomical findings an endoscopic explorative tympanotomy was finally performed. The mean preoperative air conduction (AC), bone conduction (BC) and air-bone gap (ABG) were, respectively, 60.7, 26.3 and 34.4dB. The mean postoperative AC, BC and ABG were, respectively, 33.8, 26.5 and 7.3dB, with a mean improvement of the ABG of 27.1dB. Discharge from hospital was on the first post-surgery day. No relevant postoperative complications were noted. The median follow-up was 3.6years (range 1-6). The endoscopic approach results very adequate for the diagnosis and treatment of stapes malformations, checking variations of the ossicles conformation and functioning and performing safe surgery, under direct control of middle ear structures.

The aim of this study was to establish the sound transmission characteristics of cartilage conduction proposed by Hosoi (2004), which is available by a vibration signal delivered to the aural cartilage from a transducer. Experimental study. Eight volunteers with normal hearing participated. Thresholds at frequencies of 0.5, 1, 2, and 4 kHz for air conduction, bone, and cartilage conductions were measured with and without an earplug. The sound pressure levels on the eardrum at the threshold estimated with a Head and Torso Simulator were compared between air and cartilage conductions. The force levels calibrated with an artificial mastoid at the threshold were compared between bone and cartilage conductions. The difference in the estimated sound pressure levels on the eardrum at the thresholds between air and cartilage conductions were within 10 dB. In contrast, the force levels at the thresholds for cartilage conduction were remarkably lower than those for bone conduction. These findings suggested that sounds were probably transmitted via the eardrum for cartilage conduction. The threshold shifts by an earplug showed no significant difference between bone and cartilage conductions at 0.5 kHz. At 1 and 2 kHz, the threshold-shifts increased significantly in the order of bone, cartilage, and air conductions. These results suggested that airborne sound induced by the vibration of the cartilaginous portion of the ear canal played a significant role in sound transmission for cartilage conduction. Cartilage conduction has different characteristics from conventional air and bone conductions.

Auditory steady state response (ASSR) testing provides a means to objectively estimate hearing levels in newborns and adults for whom behavioral tests prove difficult. When testing these patient groups, it is preferable that clear responses to both air and bone conduction stimuli are obtained in a short amount of time. Much of the literature addressing ASSRs, such as investigations of stimulus and recording parameters, have focused on air conduction ASSRs. The aim of this investigation was to study the amplitudes, latencies, and test times of bone conduction ASSRs elicited using amplitude- (AM), frequency- (FM), and mixed-modulated (MM) stimuli and provide suggestions for optimum recording parameters. Bone and air conduction multiple ASSRs were recorded from two groups of 20 normal-hearing adults using the Multiple Auditory Steady State Response research system. AM, FM, and MM sinusoidal tones were used (0.5-, 1-, 2-, and 4-kHz carrier frequencies), which were modulated between 78 and 92 Hz. AM depth was 100% and FM depth was 20%. ASSR amplitudes and latencies (calculated using the "preceding cycles" technique) were analyzed for MM phase settings across the cycle from 0° at 45° intervals and compared with AM responses. Optimum phase settings for bone and air conduction ASSRs were calculated using a sinusoidal model based on the amplitude data. Similar effects of stimulus type and carrier frequency were observed for bone and air conduction ASSRs. AM responses were larger in amplitude compared with FM responses. MM (at all phase settings tested) and AM response latencies increased with decreasing carrier frequency. MM phase setting had a significant (p < 0.01) sinusoidal effect on ASSR amplitudes, compared with AM responses, at 1, 2, and 4 kHz but not 0.5 kHz for air conduction and 1 and 2 kHz but not 0.5 and 4 kHz for bone conduction. Using a sinusoidal function to model this effect, MM phase settings (±95% confidence intervals) of 318° (295 to 350°) and 295° (290 to 310°) are predicted to evoke the largest responses for bone conduction ASSRs at 1 and 2 kHz, respectively. Phase settings of 293° (285 to 310°), 300° (280 to 310°), and 280° (255 to 330°) are predicted for air conduction ASSRs at 1, 2, and 4 kHz, respectively. MM phase setting had little effect on estimated latency. Test times were significantly (p < 0.01) affected by phase setting with both increases and decreases being observed. Test times for ASSRs at 1, 2, and 4 kHz could be significantly reduced if the estimated optimum phase settings are used. Different stimuli can significantly affect the amplitudes of bone conduction ASSRs. These effects are similar to those observed for air conduction ASSRs. MM stimuli with specific phase settings evoke larger bone conduction ASSRs compared with AM and FM stimuli alone, and calculations show that the time taken to obtain these responses is reduced. Implementation of the suggested optimum settings will promote efficient collection of bone conduction, and indeed air conduction, ASSR data.

To evaluate the effect of pregnancy on the hearing of women with otosclerosis. A retrospective study of women who had undergone stapedectomy. The women were equally divided into two groups: one group with children and a control group without children. Air and bone conduction, as well as discrimination, were measured before and after stapedectomy in both groups. Ninety-four women (47 with children and 47 without) were evaluated. Because many of the women had bilateral otosclerosis, the total number of ears studied was 128. Mean pure tone air and bone conduction thresholds were not worse in women with children versus those women without children. In fact, mean pre- and postoperative pure tone air and bone conduction thresholds from 500 Hz through 4,000 Hz in women with children were slightly but significantly better than women without children. There was no difference in discrimination scores between groups. Within the group with children, no significant correlation was found between number of children and hearing loss. Also, no correlation was found between breastfeeding and the amount of hearing loss. We found no adverse effect on hearing in otosclerotic women who had children compared with women without children. Even with increasing numbers of pregnancies, no deleterious impact was noted. Air conduction, bone conduction, and discrimination were not worse in women with children versus childless women. No significant correlation was found between the number of children and hearing loss, and neither did breastfeeding affect the amount of hearing loss.

Background: Two different pathways of sound transmission to the inner ear are differentiated; air conduction (AC) and bone conduction (BC). The transmission pathway of AC, which is physiological for human hearing, implies the transmission of sound to the cochlea via the ear canal, eardrum, and middle-ear ossicles, while BC bypasses the Pinna, the external auditory canal and the middle ear. The transmission pathway by BC has not been fully understood and many aspects still remain questionable. The aim of this study is to characterize two ways of direct transmission of vibrations to the inner ear by measuring hearing thresholds and vibrations of the skull. The bone-vibrator, which is usually used to measure the BC hearing thresholds in contact with the mastoid, can also be used to simulate other contents of skull, such as the eye. Methods: Ten adults (age range of 25-40) with normal hearing and five patients (age range of 21-31) with single sided profound deafness (SSD) were included in this study. The AC audiometry by pure tones was measured using insert earphones and the BC audiometry was measured by stimulating four different locations of the skull; the forehead, the temporal region, the mastoid, and the ipsilateral eyeball with two different contact pressure magnitudes of 2N and of 5N. The vibrations of the skull bones induced by air and bone conduction stimuli were measured by an accelerometer positioned between an upper and lower front incisor tooth. Results: The BC hearing thresholds by stimulating the temporal region and the mastoid were the lowest in both of normal hearing and SSD subjects and the values by both stimulations were similar. Thresholds were significantly higher for stimulations on the forehead and the eye (p<0.05). The difference between the thresholds by stimulation at the mastoid or temporal region and at the eye was more pronounced in SSD subjects (p<0.01). The averaged BC thresholds of normal subjects by stimulation on the contralateral temporal region were significantly lower than the averaged BC thresholds of SSD subjects only at the frequency of 0.25 kHz (p<0.01). The BC thresholds by stimulation on the contralateral mastoid of the normal hearing subjects were significantly lower in 5 N headband than in 2 N headband at the whole frequency range (p<0.05). The BC thresholds by stimulation on the ipsilateral mastoid of the normal hearing subjects showed significant differences between the contact pressure forces of 5 N and 2 N at the frequencies of 1, 2, and 3 kHz (p<0.5). The stimulation on the contralateral mastoid with the 5 N headband resulted in a significantly lower BC threshold than the stimulation with 5 the 2 N headband at the entire frequency range (p<0.05). In SSD subjects, the stimulation on the ipsilateral mastoid side with the 5 N headband had a significantly lower BC thresholds than stimulation with the 2 N headband at all frequencies except for 0.5 and 4 kHz (p<0.05). The BC thresholds in normal hearing subjects were significantly lower with the ipsilateral temporal stimulation than with a corresponding contralateral stimulation for the all frequencies except for 0.5 and 1 kHz (p<0.01). For the SSD subjects, the BC thresholds with the ipsilateral temporal stimulation were significantly lower at 2, 3 and 4 kHz than those with the corresponding contralateral stimulation. Skull vibrations in the normal hearing subjects showed similar behaviors at low frequencies up to 2 kHz for all stimulations except for stimulation on the eye, where vibrations were smaller. In contrast, skull vibrations measured from stimulation at the eye were increasing with higher frequencies. Under 2 kHz skull vibrations at eye were significantly smaller than those from stimulation of the mastoid, but above 2 kHz, they were significantly bigger (p<0.05). Skull vibrations between stimulation at the ipsilateral mastoid and forehead were significantly different at 0.25, 3 and 4 kHz (p<0.05). The subjects with SSD showed similar patterns. Conclusion: The patterns of BC hearing thresholds were similar in normal subjects and subjects with SSD. Hearing thresholds in all subjects were significantly better for mastoid and temple stimulation compared to eye stimulation. One reason for that may be the different pressures applied. Skull vibrations as measured at teeth did not match the same pattern as the hearing thresholds. Eye stimulation induced low vibrations below 2 kHz, but high vibrations above 2 kHz. This finding demonstrates special acoustic properties of the living organism, the distance from stimulation might also contribute. Skull-bone vibrations decreased with increasing frequency for mastoid and temple stimulation. Stimulation of soft tissue, presumably including skull contents, seems to induce high frequency skull vibrations. That might be involved with the distance form the front teeth. The transcranial attenuation of vibration should be considered especially in high frequencies.

Extensive articulation tests with laboratory equipment on an individual with a marked, primarily-conductive impairment have shown that for such an impairment for equal levels above threshold: (1) An amplifier prescribed according to the “most comfortable equal loudness curve” is superior to one prescribed according to a “most comfortable” curve, which in turn is better than a uniform amplifier; (2) Bone conduction is more satisfactory than air conduction if a high pass filter with cut-off frequency of 350 cycles is used in conjunction with the bone receiver; (3) Air and bone conduction together are superior to either alone; (4) When air conduction is used, frequencies up to 350 cycles and above 6500 cycles may be cut off without appreciably affecting the articulation. (Similar tests on an individual with monaural high frequency impairment have shown that low frequencies up to 350 cycles can be eliminated for either ear without markedly affecting the articulation.) Further tests with wearable vacuum tube aids on the individual with conductive impairment, have shown (1) the superiority of a binaural aid over a monaural aid, and the equivalence in articulation of a monaural and a diotic aid; (2) approximate equivalence of bone and air conduction, with crystal units being used in each case.

To study normative thresholds and latencies for click and tone-burst auditory brainstem response (TB-ABR) for air and bone conduction in normal infants and those discharged from neonatal intensive care units, who passed newborn hearing screening and follow-up distortion product otoacoustic emission. An evoked potential system (Vivosonic Integrity) that incorporates Bluetooth electrical isolation and Kalman-weighted adaptive processing to improve signal to noise ratios was employed for this study. Results were compared with other published data. One hundred forty-five infants who passed two-stage hearing screening with transient-evoked otoacoustic emission or automated auditory brainstem response were assessed with clicks at 70 dB nHL and threshold TB-ABR. Tone bursts at frequencies between 500 and 4000 Hz were used for air and bone conduction auditory brainstem response testing using a specified staircase threshold search to establish threshold levels and wave V peak latencies. Median air conduction hearing thresholds using TB-ABR ranged from 0 to 20 dB nHL, depending on stimulus frequency. Median bone conduction thresholds were 10 dB nHL across all frequencies, and median air-bone gaps were 0 dB across all frequencies. There was no significant threshold difference between left and right ears and no significant relationship between thresholds and hearing loss risk factors, ethnicity, or gender. Older age was related to decreased latency for air conduction. Compared with previous studies, mean air conduction thresholds were found at slightly lower (better) levels, while bone conduction levels were better at 2000 Hz and higher at 500 Hz. Latency values were longer at 500 Hz than previous studies using other instrumentation. Sleep state did not affect air or bone conduction thresholds. This study demonstrated slightly better wave V thresholds for air conduction than previous infant studies. The differences found in the present study, while statistically significant, were within the test step size of 10 dB. This suggests that threshold responses obtained using the Kalman weighting software were within the range of other published studies using traditional signal averaging, given step-size limitations. Thresholds were not adversely affected by variable sleep states.

The aim of this study was to determine the efficiency of intratympanic dexamethasone (ITD) injections as a new treatment modality in otitis media with effusion resistant to conventional therapy. We planned a nonrandomized prospective study to determine the safety and effectiveness of the direct administration of dexamethasone into middle ear cavity with chronic eustachian tube dysfunction. This study was applied on 75 ears of 64 patients aged from 12 to 60years. ITD received 47 ears of 41 patients who had previously been treated by medical or surgical therapy middle ear effusion without resolution classified as study group. They were taken conventional medical therapy again 28 ears of 23 patients classified as a control group. ITDs were administered 0.5ml/4mg per mm directly in antero-superior quadrant of tympanic membrane. These injections were repeated once a week for 4weeks. Results were evaluated by using audiometric and tympanometric measurements 1 and 3months after the treatments. Audiometric measurement shows that 9.91dB improvement in the mean air-bone gap 15.17dB in air conduction (AC) pure-tone averages (PTA) and 5.25dB bone conduction (BC) PTA. But the control group data showed only 2dB improvement in the mean air-bone gap, 3dB AC-PTA and 1.36dB BC-PTA. Tympanometric improvement was found. In 28 ears of patients (59.6%) like type B or C converted to type A in study group without complication but only in three ears (10.7%) of control group. ITD administration to the middle ear is safe and effective for the treatment of otitis media with effusion or chronic eustachian tube dysfunction. No complications like tympanic membrane perforation and/or sensorineural hearing loss have occurred.