Ossicular chain defects in adults with chronic otitis media.

BACKGROUND AND OBJECTIVE: Chronic otitis media (COM) is a common condition characterized by the perforation of the tympanic membrane and inflammation of the mucosal lining the hollow space in the middle ear and airy spaces of the temporal bone for at least 2-6 week. This study was carried out to find out the status of the middle ear ossicles in patients with COM and to correlate their status with clinical parameters. METHODS: This retrospective clinical study was conducted on 107 COM patients (52 males and 55 females; age range: 18 to 75 years) submitted to surgery in the Otology Clinic at Imam Khomeini Hospital, Ahvaz Jundishapur University of Medical Sciences, Iran. Initially, a comprehensive case-history was obtained from patients and their hearing thresholds were recorded. Then, ossicles status and their junction condition were evaluated intraoperatively. RESULTS: The malleus was found intact in 70 (65.42%), absent in 10 (9.34), and eroded in 27 (25.24%) patients. Our results revealed that the incus was intact in 33 (30.84%), eroded in 55 (51.41%) and absent in 19 (17.75%) subjects. Stapes was found intact in 54 (50.46%) cases and eroded in 53 (49.54%) cases. The mean Pure Tone Average (PTA) and Air-Bone Gap (ABG) comparisons in "intact" and "discontinuous" ossicular chain groups was not significant (Independent sample t-test, p>0.05). CONCLUSION: Our results demonstrated that incus was the most susceptible middle ear ossicle to erosion in COM, whereas the malleus was the most resistant ossicle. Furthermore, ABG and PTA values cannot be considered as a potential preoperative predictor for ossicular chain status.

Manubrio-incudo-stapedioplasty for reconstruction of Austin-Kartush type B ossicular defects.

OBJECTIVE: Manubrio-incudo-stapedioplasty functional outcomes were compared to those of other methods for reconstructing Austin-Kartush type B ossicular defects. METHODS: Forty-two patients underwent Austin-Kartush type B ossicular defect reconstruction using: manubrio-incudo-stapedioplasty (13 patients), an autologous incus (19 patients) or a titanium ossicular replacement prosthesis (10 patients). For manubrio-incudo-stapedioplasty reconstruction, the malleus head was removed, the manubrium was relocated posteriorly and the incus short process was placed on the mobile footplate. The manubrium was placed on the incus body groove and bone cement was applied to stabilise the manubrium-incus junction. Pre- and post-operative hearing thresholds were assessed. RESULTS: The air-bone gap decreased from 25.9 ± 6.0 dB to 12.3 ± 5.0 dB (p < 0.05) in the manubrio-incudo-stapedioplasty group. The hearing gain was 13.6 ± 5.2 dB for manubrio-incudo-stapedioplasty, 3.4 ± 14.2 dB with the autologous incus, and 3.3 ± 11.07 dB with the titanium ossicular replacement prosthesis. Hearing improvement was greater for manubrio-incudo-stapedioplasty compared to the other reconstruction methods (p < 0.05). CONCLUSION: Manubrio-incudo-stapedioplasty resulted in satisfactory hearing outcomes in patients with Austin-Kartush type B ossicular defects. This technique can be considered a stable, inexpensive and effective method to reconstruct Austin-Kartush type B ossicular defects.

Three-dimensional force analysis of surgical manipulations at the long process of the incus.

PURPOSE: Surgical manipulation with application of inappropriate force may damage middle ear structures leading to hearing loss. This work analyzes the forces applied in simulated otosurgical exercises in a laboratory set-up by measuring the spatial components of applied forces with objective assessment criteria. With these criteria, the individual force characteristics applied by the surgeon can be quantified and an objective feedback can be given about their surgical maneuvers. METHODS: A natural size model of the human incus was mounted on a load cell to measure the spatial forces in all three directions during different manipulation tasks performed under the microscope by ten surgeons from our department having different levels of experience in otosurgery. The motions of the incus model and the instrument tip were recorded simultaneously with a video camera. RESULTS: Independent of surgical experience, a three-dimensional force pattern could be detected with components transverse to the desired force directions. The measured forces applied by trainees showed larger variations in magnitude, in spatial distribution and in temporal course than those applied by experienced surgeons. A better repeatability of identical tasks, constancy of force patterns and low peak force values could be seen in the group of experienced surgeons. CONCLUSIONS: The laboratory system presented in this study using simultaneous video and 3-D force registration allows the objective assessment of surgical manipulations, e.g., at the long process of the incus. Training with video and force feedback provides information about surgical techniques and skill development of surgeons and has the potential to shorten the learning curve and to diminish intra-operative risks to patients.

First results of a novel adjustable-length ossicular reconstruction prosthesis in temporal bones.

OBJECTIVES/HYPOTHESIS: The performance of an ossicular replacement prosthesis (ORP) is influenced by its alignment and appropriate tension between the tympanic membrane and the stapes footplate. A novel ORP with a flexible element that potentially allows for length adjustment in situ is presented and tested for acoustic performance. STUDY DESIGN: Laser Doppler vibrometry in fresh human cadaveric temporal bones was used to test the acoustic performance of the adjustable ORP relative to standard prostheses used for ossiculoplasty. METHODS: The three-dimensional (3D) velocity of the stapes posterior crus was measured in the 0.2- to 20-kHz range using a Polytec CLV-3D laser Doppler vibrometer. The middle ear cavity was accessed through a facial recess approach. After measuring the normal response, the incus was removed and stapes velocity was measured in the disarticulated case, then after insertion of the new prosthesis, a conventional prosthesis (Kurz BELL Dusseldorf type), and a sculpted autologous incus prosthesis in each temporal bone. The 3D stapes velocity transfer function (SVTF) was calculated for each case and compared. RESULTS: The novel ORP design restored stapes velocity to within 6 dB (on average) of the intact response. No significant differences in 3D-SVTF were found between the new, conventional, or autologous ORPs. CONCLUSIONS: The inclusion of an in situ adjustable element into the ORP design did not adversely affect its acoustic performance. The adjustable element may increase the ease of achieving optimal ORP placement, especially through a facial recess approach. LEVEL OF EVIDENCE: NA Laryngoscope, 126:2559-2564, 2016.

Congenital incus fixation to the fallopian canal.

IMPORTANCE: An isolated congenital anomaly of the ossicular chain is a rare finding in an ear that, otherwise, appears clinically normal. The most common congenital ossicular anomaly is fixation of the stapes footplate. The least common congenital ossicular anomaly is isolated incus fixation, with only a few reported in the literature. OBSERVATIONS: We describe a woman in her 50s with a long history of left-sided hearing loss and unremarkable neurotologic findings aside from a tuning-fork examination result suggestive of left-sided conductive hearing loss. Intraoperatively, she was found to have isolated fixation of the incus to the fallopian canal. The incus-fallopian canal fixation was separated, and an autologous bone graft was placed between the lenticular process and stapes capitulum to create elevation and prevent refixation. One month postoperatively, an audiogram revealed a nearly complete air-bone gap closure. CONCLUSIONS AND RELEVANCE: Patients who present with conductive hearing loss, normal physical examination findings, and an apparent normal radiograph are generally assumed to have otosclerosis. This case illustrates an unanticipated unique anomaly that was surgically corrected by releasing the bony fixation of the incus to the fallopian canal and placing an autologous bone graft at the incostapedial joint.

Ossicular reconstruction for incus long-process defects: bone cement or partial ossicular replacement prosthesis.

OBJECTIVE: The objective of this study was to compare hearing results in patients undergoing ossiculoplasty with bone cement (BC) vs partial ossicular replacement prosthesis (PORP) in cases of incudostapedial discontinuity during tympanoplasty surgeries. STUDY DESIGN: Case series with chart review. SETTING: Tertiary referral center. SUBJECTS: A total of 44 patients with incudostapedial discontinuity, 21 operated on with BC and 23 operated on with PORP, were enrolled in this study. METHODS: Preoperative and postoperative audiograms at 12 months were evaluated. Pure-tone averages and air-bone gaps (ABGs) were calculated according to the guidelines. RESULTS: The ABG was 26.61 dB preoperatively and 9.76 dB postoperatively in the BC group. The hearing gain in ABG was statistically significant (P = .0001). The preoperative and postoperative ABGs in the PORP group were 29.48 and 8.89 dB, respectively. The hearing gain in ABG was statistically significant (P = .0001). When the groups were compared for mean gains in the ABG, the difference was not statistically significant (P = .192). The postoperative ABG of less than 20 dB was achieved by 90.4% in the BC group and 86.9% in the PORP group. This difference was not statistically significant (P = .745). No adverse reactions or complications were observed. CONCLUSIONS: Both BC and PORP are reliable and efficient methods for the repair of incudostapedial joint defects. There is no difference between these 2 methods, based on the hearing results. Additional research is necessary to determine the maximum incudostapedial defect length suitable for bone cement repair.

Mechanisms of tympanic membrane and incus mobility loss in acute otitis media model of guinea pig.

Acute otitis media (AOM) is a rapid infection of middle ear due to bacterial or viral invasion. The infection commonly leads to negative pressure and purulent effusion in the middle ear. To identify how these changes affect tympanic membrane (TM) mobility or sound transmission through the middle ear, we hypothesize that pressure, effusion, and structural changes of the middle ear are the main mechanisms of conductive hearing loss in AOM. To test the hypothesis, a guinea pig AOM model was created by injection of Streptococcus pneumoniae. Three days post inoculation, vibration of the TM at umbo in response to input sound in the ear canal was measured at three experimental stages: intact, pressure-released, and effusion-drained AOM ears. The vibration of the incus tip was also measured after the effusion was removed. Results demonstrate that displacement of the TM increased mainly at low frequencies when pressure was released. As the effusion was removed, the TM mobility increased further but did not reach the level of the normal ear at low frequencies. This was caused by middle ear structural changes or adhesions on ossicles in AOM. The structural changes also affected movement of the incus at low and high frequencies. The results provide new evidence for understanding the mechanism of conductive hearing loss in AOM.

Prosthetic reconstruction from the tympanic membrane to the stapes head or to the stapes footplate? A laser Doppler study.

BACKGROUND: In the absence of the incus, many surgeons believe that reconstruction from the tympanic membrane to the stapes head is more effective than reconstruction to the stapes footplate. This has rarely been tested empirically. Published better clinical results with reconstruction to the stapes head might simply reflect less underlying disease in ears with an intact stapes superstructure. OBJECTIVE: To compare vibration transmission of these two forms of prosthetic reconstruction. METHODS: A fresh human cadaveric temporal bone model was used. Round window vibrations in response to sound in the ear canal were measured with a laser Doppler vibrometer. After incus removal, the discontinuity was repaired using a titanium prosthesis. Reconstruction from the tympanic membrane to the stapes head was compared to reconstruction to the stapes footplate. RESULTS: Reconstruction of both types decreased round window vibrations by 10 to 15 dB between 500 and 3000 Hz compared to the intact middle ear. Reconstruction to the stapes head performed 5 to 10 dB better at lower frequencies (500-2000 Hz), but this was only statistically significant at 1 and 2 kHz. CONCLUSIONS: There is only a 5 to 10 dB mechanical advantage gained by reconstruction from the tympanic membrane to the stapes head compared to reconstruction to the footplate for frequencies between 1 and 2 kHz.

Application of active middle ear implants in patients with severe mixed hearing loss.

OBJECTIVE: To determine the long-term benefit of the Vibrant Soundbridge (VSB) middle ear implant in patients with severe mixed hearing loss and to compare it with other hearing devices. DESIGN: A retrospective analysis. SETTING: University-affiliated medical center. PATIENTS: Six patients with severe mixed hearing loss and a mean sensorineural hearing loss component between 40 and 70 dB. INTERVENTIONS: Patients received a VSB with the floating mass transducer (FMT) coupled to the round window or to the oval window via a residual stapes structure. MAIN OUTCOME MEASURES: Functional gain and speech recognition results. Results are compared with 2 control groups matched for mean sensorineural hearing loss: 1) patients with mixed hearing loss and a bone-anchored hearing device, and 2) patients with sensorineural hearing loss and traditional implantation of the VSB. RESULTS: There is large variance in functional gain between the patients suggesting high variability in the effectivity of the FMT coupling. The speech recognition results for the experimental group were not systematically better than in either control group. CONCLUSION: There is large variability in results that might be ascribed to coupling effectivity. On the average, speech recognition results were not better or worse than those found in patients with similar hearing loss fitted with bone-anchored hearing devices.

Incus augmentation with glass ionomer cement in primary and revision stapes surgery.

In stapedotomy, augmentation of the long process of the incus is necessary when the structure is too short or thin or when the bone has been eroded to the point that it is not possible to satisfactorily attach a piston prosthesis to it. One substance that has been used to augment the long process is glass ionomer cement (GIC). GIC is a dental bone cement that is finding new uses in otologic procedures. We conducted a retrospective study of 10 stapedotomies (6 primary and 4 revision cases) that included the use of GIC to augment an insufficient long process. In all 10 cases, surgery was successful and without complication. A comparison of pre- and postoperative audiometry revealed significant improvements in mean air-conduction threshold and air-bone gap following surgery. Our findings suggest that GIC is safe and effective in augmenting the long process of the incus during both primary and revision stapedotomy.

Malleostapedotomy in tympanosclerosis patients.

OBJECTIVES: To present our personal experience of a series of 10 patients suffering from tympanosclerosis with functional blocking of the stapes or footplate, who underwent malleostapedotomy surgery. The criteria for patient selection for this type of operation, and its results and complications, are discussed. METHODS: Prospective study. RESULTS: Incus and malleus dysfunction was observed in 70 per cent of cases, either alone or combined with fixation of the stapes. The post-operative hearing results were considered to be satisfactory (i.e. within 20 dB) in 80 per cent of cases. Only one patient had sensorineural hearing loss over 10 dB. CONCLUSIONS: Malleostapedotomy has proved its practicability in the treatment of patients with fixed footplate or stapes complicated by ankylosis of the incudomalleolar joint. This procedure can be considered a further, valid technique within the otologist's surgical armamentarium.

Intraoperative ossicular loading with the Otologics fully implantable hearing device.

CONCLUSIONS: Use of the recently introduced intraoperative loading instrumentation during surgery improves the coupling efficiency and consistency of a fully implantable hearing device to the ossicles and ultimately leads to better patient performance with the device. BACKGROUND: Patient performance with an implantable hearing device is dependent on effective coupling of the implant to the middle ear ossicles. New intraoperative instrumentation aids the surgeon in coupling the implantable hearing device and consistently optimizes patient performance. MATERIALS AND METHODS: The middle ear transfer function for the Otologics MET Ossicular Stimulator (METF(MET)) is a measure of transducer coupling efficiency, defined as acoustic threshold (in dB HL) minus implant threshold (in dB MET). This transfer function was measured in the Otologics US Phase I Semi-Implantable Clinical Trial without intraoperative loading instrumentation and in the Otologics US Phase I Fully Implantable Clinical Trial with intraoperative loading instrumentation. The same operative techniques and transducer design were used in both studies. The theory of operation and surgical technique for using this instrumentation are described. RESULTS: In the semi-implantable clinical trials, METF(MET) was -10 to -15 dB for frequencies above 1 kHz, and dropped to -15 to -20 dB for lower frequencies. Fully implantable clinical trial results were 10-20 dB better than the semi-implantable trial results, with less variability at all frequencies. These findings indicate more consistent and better coupling efficiency of the transducer to the ossicles.

Movements of the intact and reconstructed ossicular chain during changes in static pressure.

OBJECTIVE: To investigate the motion of the normal and reconstructed ossicular chain during changes in static pressure. MATERIAL AND METHODS: Experiments were carried out using seven fresh human temporal bones Using digital photography, movements of the malleus were measured during incremental pressure changes between +500 and -500 daPa with the incus in situ and following its removal. The pattern of movement of the ossicles was recorded in the form of digital video clips. This was carried out with the ossicular chain intact and also when it had been reconstructed with an incus graft and four different types of artificial prosthesis. RESULTS: The lateral to medial movement of the malleus during changes in static pressure is converted into a predominantly superior to inferior movement of the incus. Conventional reconstructions using a graft or prosthesis transmit the malleus movement directly to the stapes so that it is pushed in and out of the oval window. Reconstructions with prostheses which restore the mammalian three-ossicle pattern, by contrast, move in a similar manner to the normal incus. CONCLUSION: Ears reconstructed using conventional techniques are more at risk from pressure changes than those in which a "physiological" method is used.

Laser-assisted tympanoplasty for preservation of the ossicular chain in cholesteatoma.

We report the use of potassium titanyl phosphate laser-assisted tympanoplasty in amputations of the malleus and incus in 2 patients with cholesteatoma medial to those ossicles that had not destroyed the ossicular chain continuity. In both cases, the laser successfully removed portions of the ossicles to allow removal of the cholesteatoma; importantly, the laser preserved certain ossicular ligaments, thus keeping the ossicular chain continuous. Postoperatively, both patients showed satisfactory hearing. Although the prevalence of cholesteatoma medial to the ossicles with maintained ossicular continuity is limited, the laser-assisted procedure described here is useful for maintaining hearing ability in these cases.

First audiometric results with the Vibrant soundbridge, a semi-implantable hearing device for sensorineural hearing loss.

The Vibrant soundbridge is a semi-implantable hearing device. The implanted electromagnetic transducer is attached to the incus and it is linked by telemetry to the externally worn audio processor. In Nijmegen, this device has been applied to seven patients with moderate or severe sensorineural hearing loss (PTA between 43 and 71 dB HL) who could not tolerate ear moulds. As the amplification of the device depends on the input level (amplifier with wide dynamic range compression), loudness scaling measurements were performed. The gain as a function of input level was determined from aided and unaided loudness growth curves. The mean gain was 21 dB at an input level of 40 dB SPL. The mean gain decreased to 5 dB at an input level of 90 dB SPL. Measured gain values were lower than target values prescribed by the FIG6 method, mainly however for the low-frequency range and for low-level sounds. It was concluded that this device is very promising for patients who cannot tolerate an ear mould.

The value of methylprednisolone in the treatment of an experimental sensorineural hearing loss following drill-induced ossicular chain injury: a randomized, blinded study in guinea-pigs.

In a previously established animal model a standardized drill-induced injury to the body of the incus was applied, and the effects on hearing were characterized by electrocochleography. In a placebo-controlled, randomized, blinded study methylprednisolone showed no protective effect in reducing or improving the auditory threshold shifts, which occurred within seconds after drilling and remained stable throughout the 5-week observation period. Therefore the otologic surgeon must pay close attention to avoiding any contact of a rotating burr with an ossicle in an intact ossicular chain.

Acoustic effect of malleus head removal and tensor tympani muscle section on middle ear reconstruction.

In the reconstruction of ears with a missing incus, an incus replacement prosthesis (IRP) is commonly used to connect malleus and stapes. In some cases, it is necessary to resect the malleus head and/or section the tensor tympani muscle (TTM) tendon. The acoustic effects of these maneuvers have not been well studied. We performed experiments in a temporal bone model to measure the effect of these maneuvers on middle ear sound transmission. Measurements of umbo and stapes displacement were made before and after malleus head removal and TTM section plus incus replacement with an IRP. After malleus head removal, there was a peak gain in stapes displacement of 6 dB below 0.5 kHz and 8 dB above 2.5 kHz. TTM section had a similar but lesser effect. A clinical example is described.

Middle ear involvement in children with chronic rheumatoid juvenile arthritis.

In a selected sample of patients affected by juvenile rheumatoid arthritis (JRA) little is known about middle ear involvement, even though many synovial joints are affected. Multifrequency tympanometry was used to measure admittance, conductance, susceptance and phase angle at different probe frequencies and resonant frequencies. In all, 35 children with JRA and a control group (30 children) were studied. Findings showed that mean resonant frequency values in all children with JRA were greater than in the control children. The multifrequency tympanometry parameters measured in acute JRA subjects are not different from parameters of remission JRA subjects except for a change in the phase angle. The changes found are due to involvement of the incudomalleolar and incudostapedial joints.

Tomografía computada del oído con malformaciones congénitas: evaluación prequirúrgica / Computed tomography of the congenital anomalies of the ear: preoperatory evaluation

Se exploraron con tomografía computada de alta resolución 60 oídos de 44 pacientes con malformaciones congénitas de los oídos externo y medio, valorando las alteraciones anatómicas según un criterio pre-establecido. Se establecen algunos parámetros para dar mayor objetividad a este análisis. Se encontrtó alteración bilateral en 26 pacientes y unilateral en 28. De los 60 oídos, 39 (65 por ciento) tenían atresia del conducto auditivo externo y 21 (35 por ciento) estenosis. El oído medio era de tamaño adecuado en 43 (72 por ciento) oídos inadecuado en 17 (28 por ciento). El trayecto del nervio facial se encontró normal en 39 (65 por ciento) y alterado en 21 (35 por ciento) oídos. La proporción de anomalías en el curso del nervio facial fue mucho mayor en los oídos con atresia, 19 de 39 (49 por ciento) que presentaban estenosis del conducto. Se propone una escala de puntuación para seleccionar a los candidatos a la cirugía, según el pronóstico funcional y riesgo