Bone mineral density of the incus body and long process in patients with chronic otitis media and its relationship with functional outcome in type II tympanoplasty.

BACKGROUND: Inflammatory conditions such as chronic otitis media (COM) can cause irreversible impairments in the microarchitecture and functions of the incus, which subsequently leads to conductive hearing loss. OBJECTIVES: To investigate bone mineral density (BMD) of the incus body (IB) and long process (ILP) on preoperative temporal CT in COM patients with and without incudo-stapedial joint discontinuity (ISJD), and also to determine the association between BMD values and the postoperative air-bone gap (ABG) in the ISJD group. MATERIAL AND METHODS: The mean IB density (IBD)/occipital bone density (OBD) and ILP density (ILPD)/OBD values were compared between the patients with and without ISJD. The correlation between ABG gain and preoperative incus density values was assessed in the ISJD group. RESULTS: The mean IBD/OBD and ILPD/OBD values were significantly higher in patients with intact ISJ. There was a moderate positive correlation between postoperative ABG gain and ILPD/OBD values in the ISJD group. CONCLUSION AND SIGNIFICANCE: The decrease in BMD of the incus may involve ILP as well as IB in patients with ISJD caused by ILP lysis in COM. A higher preoperative ILPD/OBD was correlated with a higher postoperative ABG gain in COM patients with ISJD.

Exclusive endoscopic management of incus long process major defects: conventional incus interposition versus malleostapediopexy.

PURPOSE: The aim of the current study is to compare the surgical and audiometric results of conventional incus interposition (IP) versus malleostapediopexy (MS) in incus long process large defects. METHODS: A total of 71 patients (incus IP group n = 37, MS group n = 34) were enrolled in this study. All patients enrolled in the current study underwent ossiculoplasty via an exclusive endoscopic transcanal approach. Pre- and postoperative audiometric measurements and air-bone gap (ABG) values were compared, and if the postoperative ABG value was less than 20 dB, ossiculoplasty was considered successful. Graft success rates and complications were also compared. RESULTS: The average auditory gain was 14.7 ± 4.2 dB in the incus IP group and 18.3 ± 5.1 dB in the MS group. The auditory gain was significantly greater in the MS group relative to the incus IP group (p = 0.012). Ossiculoplasty success (postoperative ABG value < 20 dB) rate was 70.3% in the incus IP group patients and 88.2% in the MS group patients (p < 0.001). There was no significant difference in terms of graft success rate between groups (p > 0.05) and the overall graft uptake rate was 91.5% (65/71). CONCLUSION: Malleostapediopexy-bridging of malleus and stapes using bone cement-is an effective, reasonable, and more efficient technique in terms of auditory outcomes relative to the conventional incus interposition in endoscopic transcanal management of incus long process major defects.

Linear transmission between malleus and stapes in cases with incus necrosis.

OBJECTIVE: The outcome of cartilage interposition ossiculoplasty was assessed in cases of incus necrosis after posterior malleus repositioning in the plane of the stapes, in terms of hearing gain after ossicular reconstruction. METHODS: A retrospective observational study was conducted of 30 patients admitted to an Ain Shams University hospital from March 2021 to September 2021. All patients with ossicular disruption due to chronic suppurative otitis media and hearing loss of more than 40 dB were included in the study. Pure tone audiometry was conducted for each patient after three months, six months and one year post operation. RESULTS: The audiogram showed a post-operative air-bone gap of 20 dB or less in 83.33 per cent of patients (n = 25) at three months post-operatively and in 80 per cent of patients after six months; after one year, the results remained the same. CONCLUSION: The use of cartilage interposition after malleus posterior mobilisation represents an excellent partial ossicular replacement technique.

Techniques of Endoscopic Ossiculoplasty.

The utilization of endoscopes in modern otology has evolved from diagnostic purposes to the development of exclusive endoscopic ear surgery. This technique offers a panoramic view of the middle ear and provides an optimal magnification of the oval window region, the stapes' suprastructure, and the footplate, allowing great precision in prosthesis positioning during ossiculoplasty (OPL). Various techniques for ossicular chain reconstruction have been described in the literature. Either autologous or synthetic materials can be used for reconstruction. The use of a patient's own tissue minimizes the risk of implant rejection or extrusion of the prosthesis through the tympanic membrane. On the other hand, synthetic materials like titanium are light and rigid and do not require time-consuming prosthesis remodeling. The main objective of this article is to present a comprehensive step-by-step guide that serves as a surgical manual for exclusive endoscopic OPL. This guide will explain various forms of OPL using synthetic and autologous materials. The goal is to provide a comprehensive understanding of the various surgical techniques and support the integration into clinical practice.

The TORP-PORP: A Tympanoplasty Technique for Isolated Defects of the Stapes Suprastructure.

OBJECTIVE: Investigating the outcomes of a surgical approach to treat isolated defects of the stapes suprastructure, using a modified total ossicular replacement prosthesis (TORP) prosthesis as a PORP between the footplate and the incus, effectively creating a TORP-PORP configuration. PATIENTS: Eleven patients (mean age, 37.2 years; 36% male and 64% female) between the years 2007 and 2022. INTERVENTIONS: Therapeutic (ossiculoplasty). MAIN OUTCOME MEASURES: Hearing gain (in dB) in air conduction thresholds at 0.5, 1, 2, 3, and 4 kHz, stability of bone conduction, revision rate. RESULTS: Significant improvement in air conduction between the preoperative and the postoperative cohorts (p = 0.002) with a mean postoperative hearing level of 30.00 ± 5.25 dB. The bone conduction remained stable. We encountered no perioperative complications, and there were no revisions surgery. CONCLUSIONS: The described ossiculoplasty procedure is a safe and effective approach to treat isolated defects of the stapes suprastructure.

Performance of personalised prosthesis under static pressure: Numerical analysis and experimental validation.

This study investigates the performance of personalised middle ear prostheses under static pressure through a combined approach of numerical analysis and experimental validation. The sound transmission performances of both normal and reconstructed middle ears undergo changes under high positive or negative pressure within the middle ear cavity. This pressure fluctuation has the potential to result in prosthesis displacement/extrusion in patients. To optimise the design of middle ear prostheses, it is crucial to consider various factors, including the condition of the middle ear cavity in which the prosthesis is placed. The integration of computational modelling techniques with non-invasive imaging modalities has demonstrated significant promise and distinct prospects in middle ear surgery. In this study, we assessed the efficacy of Finite Element (FE) analysis in modelling the responses of both normal and reconstructed middle ears to elevated static pressure within the ear canal. The FE model underwent validation using experimental data derived from human cadaveric temporal bones before progressing to subsequent investigations. Afterwards, we assessed stapes and umbo displacements in the reconstructed middle ear under static pressure, with either a columella-type prosthesis or a prosthetic incus, closely resembling a healthy incus. Results indicated the superior performance of the prosthetic incus in terms of both sound transmission to the inner ear and stress distribution patterns on the TM, potentially lowering the risk of prosthesis displacement/extrusion. This study underscores the potential of computational analysis in middle ear surgery, encompassing aspects such as prosthesis design, predicting outcomes in ossicular chain reconstruction (OCR), and mitigating experimental costs.

Predictive Factors and Audiometric Outcome Comparison Between Titanium Prosthesis and Autologous Incus in Traumatic Ossicular Injury.

OBJECTIVES: To investigate the etiology and ossicular pathology of traumatic ossicular injury in Taiwan and examine the hearing outcomes and predictive factors between the titanium prosthesis and autologous incus groups. METHODS: We retrospectively analyzed patients with traumatic ossicular injury from 2011 to 2020 in Taiwan. Patients were divided into the titanium or autologous group according to the surgical materials used. The audiometric outcomes and predictive factors of ossiculoplasty were analyzed between groups. RESULTS: Twenty patients with ossicular chain discontinuity were enrolled (8 in the titanium group and 12 in the autologous group). The postoperative hearing threshold (26.6 ± 8.9 dB) and air-bone gap (10.3 ± 5.6 dB) improved significantly compared with the preoperative hearing threshold (50.7 ± 13.3 dB) and air-bone gap (29.9 ± 11.0 dB). The improvements in the hearing threshold and air-bone gap were not significantly different between the titanium and autologous groups. Our patients presented an improvement in hearing restoration with 65% closure of the air-bone gap in 0 to 10 dB range and 30% in 11 to 20 dB range, without sensorineural hearing loss during surgery. Univariate regression analysis revealed that vertigo, benign paroxysmal positional vertigo, and temporal bone fracture may serve as negative factors influencing the air-bone gap gain. CONCLUSIONS: Ossiculoplasty with both titanium prosthesis and autologous materials demonstrated favorable hearing recovery in traumatic ossicular injury. Vertigo, benign paroxysmal positional vertigo, and temporal bone fracture may serve as negative predictive factors of the hearing benefit after surgery.

Minimally invasive ossiculoplasty via an endoscopic transtympanic approach.

INTRODUCTION: The aim of this study was to evaluate the feasibility of ossiculoplasty via a minimally invasive endoscopic transtympanic approach (ETTA). CASE SERIES: We investigated the exposure of target structures (incus and stapes) on 4 human temporal bones by placing an endoscope into the middle ear cleft through the 4 tympanic quadrants. Then, on 3 additional specimens, we performed an incudostapedial disjunction and repaired it with a drop of hydroxyapatite cement via ETTA. We measured the size of tympanic perforation, and the acoustic transfer function of the middle ear (125-8000Hz) before and after repair by placing an insert in the external auditory canal and recording the acoustic signal in the utricle by a microphone. The acoustic signal gain was estimated in dB µV. Exposure was similar in all four quadrants but ergonomics was better with a posteroinferior myringotomy. Ossicular chain repair was conducted successfully in all cases and the acoustic transfer function of the middle ear was significantly improved. Residual tympanic perforation (n=3) was 2±0.3mm in diameter. CONCLUSION: ETTA to reconstruct incudostapedial joint with bone cement was feasible and effective. It opens perspectives for robot-based procedures guided by augmented reality.

Anatomic and morphometric examination of auditory ossicles in sheep.

It is important to know the morphometry of the auditory ossicles for middle ear surgical applications. The present study aims to investigate the morphometric measurements of sheep auditory ossicles and the relationship between these ossicles. In this study, 100 malleus, incus and stapes of 50 Akkaraman sheep were examined using at trinocular stereo microscope and a total of 19 morphometric measurements were taken. The mean values of the morphometric measurements were obtained, and correlation analysis was performed between each part of each auditory ossicle. Similarities were found between the measurements of the lengths of the malleus, manubrium mallei and incus, and the width of the base of the stapes with morphometric measurements in human auditory ossicles. A significant positive correlation was found between the length of the malleus with the length of the manubrium mallei, between the length of the incus with the lengths of the long crus and corpus incudis, between the length of the stapes with the lengths of the rostral crus, caudal crus, caput stapedis, and the length and width of the intercrural foramen. Due to the anatomic similarities between sheep and human auditory ossicles, it was concluded that the auditory ossicles of sheep are suitable for use in the training of human ear surgery applications.

Reconstructive ossiculoplasty options in primary cholesteatoma surgeries with an intact stapes.

PURPOSE: In primary cholesteatoma patients, incus destruction with an intact and mobile stapes is a frequent finding. Different techniques have been described to restore the ossicular chain, including incus interposition, stapes augmentation and type III tympanoplasty. Controversy about postoperative hearing results in open versus closed surgical techniques exist. METHODS: We performed a retrospective analysis of clinical, surgical and audiometric data of patients with primary cholesteatoma surgery operated between 2010 and 2020, and a mobile stapes and one-stage ossicular reconstruction. Pre- and post-operative audiograms were compared for the different surgical groups, mainly focusing on postoperative air-bone gap. Mastoid pneumatization and ventilation was also considered. RESULTS: The mean postoperative air-bone gap (0.5-4 kHz) of the 126 included patients was 20 dB. Hearing after type III tympanoplasty (26 dB) was worse than incus interposition (19 dB) and stapes augmentation (20 dB). Hearing after an open (23 dB) versus closed (19 dB) surgical technique was significantly different. No improvement in air-bone gap was observed for the higher frequencies. CONCLUSION: A residual postoperative air-bone gap should be considered after primary cholesteatoma surgery with intact and mobile stapes. Incus interposition in closed cavity operation is the optimal situation, but open cavity surgery should not be avoided because of hearing. Extent of the disease is prioritized and poorer ventilation before and after surgery may affect postoperative hearing.

Cholesteatoma Severely Impacts the Integrity and Bone Material Quality of the Incus.

Cholesteatoma can lead to progressive destruction of the auditory ossicles along with conductive hearing loss but precise data on the microstructural, cellular, and compositional aspects of affected ossicles are not available. Here, we obtained incus specimens from patients who had cholesteatoma with conductive hearing loss. Incudes were evaluated by micro-computed tomography, histomorphometry on undecalcified sections, quantitative backscattered electron imaging, and nanoindentation. Results were compared with two control groups taken from patients with chronic otitis media as well as from skeletally intact donors at autopsy. The porosity of incus specimens was higher in cholesteatoma than in chronic otitis media, along with a higher osteoclast surface per bone surface. Histomorphometric assessment revealed higher osteoid levels and osteocyte numbers in cholesteatoma incudes. Incudes affected by cholesteatoma also showed lower matrix mineralization compared with specimens from healthy controls and chronic otitis media. Furthermore, the modulus-to-hardness ratio was higher in cholesteatoma specimens compared with controls. Taken together, we demonstrated increased porosity along with increased osteoclast indices, impaired matrix mineralization, and altered biomechanical properties as distinct features of the incus in cholesteatoma. Based on our findings, a possible impact of impaired bone quality on conductive hearing loss should be further explored.

Comparison of dislocation rates of Teflon and Titanium stapes prostheses: a retrospective survival analysis on 855 patients.

BACKGROUND: Stapes prosthesis dislocation is the first cause of revision stapes surgery. To our knowledge, there is no data about stability of the incus attachment of manual crimped prosthesis of different materials. This study aimed to compare the dislocation incidence between titanium and fluoroplastic stapes prostheses. METHOD: A monocentric retrospective cohort study was conducted between January 2013 and June 2022 in a tertiary-care center. All patients that underwent a primary stapes surgery with manually crimped fluoroplastic or titanium prostheses were included. Prosthesis dislocation from the incus was identified intraoperatively or with CT scan. The incidence of stapedial prosthesis dislocation over time was estimated using the Kalbfleisch and Prentice survival analysis method. Other indications for revision surgery prior to prosthesis dislocation were considered as competing events. Differences in the cumulative incidence functions between the fluoroplastic group and the titanium group was assessed using the Gray's test. RESULTS: Eight hundred and fifty-five patients underwent primary stapes surgery during the study period. Fluoroplastic prosthesis was used in 758 (88.7%) cases and titanium prosthesis in 97 (11.3%) cases. Median follow-up was 51.7 months (28.4-80.1). Dislocation was observed in 23 (3.0%) patients with fluoroplastic prosthesis and none (0.0%) in the titanium group. The probability of prosthesis dislocation at two years after surgery was 3.5% in the Teflon group and 0.0% in the Titanium group. No significant difference was found in the cumulative incidence of prosthesis dislocation between the fluoroplastic group and the titanium group (p = 0.12). CONCLUSIONS: Despite lack of statistical power, our results suggest a trend in a more stable incus attachment of manually crimped titanium stapes prosthesis compared to fluoroplastic over time. Further prospective randomized studies could be valuable to assess our findings.

Assessment of the ability of the radiological incudo-stapedial angle to predict the stapedotomy technique type: a prospective case-series study.

PURPOSE: This study aimed to propose a radiological classification of the incudo-stapedial angle by preoperative high-resolution computed tomography (HRCT) images and to highlight its importance for predicting the use of reversal-steps stapedotomy (RSS) rather than the traditional non-reversal technique. METHODS: We included 83 candidates for stapedotomy operation. Two physicians measured the radiological incudo-stapedial joint angle in the preoperative HRCT. According to this measurement, the radiological incudo-stapedial joint was classified into three types: obtuse, right, and acute. In addition, this radiological classification was correlated with the intraoperative use of the stapedotomy technique, either reversal or non-reversal. RESULTS: The RSS technique was used in forty-two (97.7%) cases with an obtuse angle and twenty-six (89.7%) with a right angle. At the same time, the traditional non-reversal technique was used in all patients with an acute angle. The three groups differed significantly regarding the method used for stapedotomy (P value < 0.001). Moreover, Spearman's correlation coefficient revealed a significant correlation between the used technique and the radiological type of the incudo-stapedial angle (P value < 0.001). CONCLUSIONS: This prospective study proposed a preoperative radiological classification of the incudo-stapedial angle. This classification was significantly correlated with the type of stapedotomy technique. The RSS technique was feasible in most cases with an obtuse and right radiological incudo-stapedial angle. In contrast, the non-reversal method was used in all patients with an acute radiological incudo-stapedial angle. This radiological classification could predict the choice for the stapedotomy technique with an accuracy of 95.18%, a sensitivity of 73.33%, and a specificity of 100%.

Ecomorphological correlates of inner and middle ear anatomy within phyllostomid bats.

Echolocation is the primary sense used by most bats to navigate their environment. However, the influence of echolocating behaviors upon the morphology of the auditory apparatus remains largely uninvestigated. While it is known that middle ear ossicle size scales positively with body mass across mammals, and that peak call frequency scales negatively with body mass among bats, there are still large gaps in our understanding of the degree to which allometry or ecology influences the morphology of the chiropteran auditory apparatus. To investigate this, we used µCT datasets to quantify three morphological components of the inner and middle ear: ossicle size, ossicle shape, and cochlear spirality. These data were collected across 27 phyllostomid species, spanning a broad range of body sizes, habitats, and dietary categories, and the relationships between these variables and ear morphology were assessed using a comparative phylogenetic approach. Ossicle size consistently scaled with strong negative allometry relative to body mass. Cochlear spirality was significantly (p = .025) associated with wing aspect ratio (a proxy for habitat use) but was not associated with body mass. From a morphological perspective, the malleus and incus exhibited some variation in kind with diet and call frequency, while stapes morphology is more closely tied to body size. Future work will assess these relationships within other chiropteran lineages, and investigate potential morphological differences in the middle and inner ear of echolocating-vs-non-echolocating taxa.

Radiological and audiological predictors of stapes destruction in adherent pars tensa.

PURPOSE: Progressive adherent pars tensa occasionally induces ossicular erosion. Specifically, stapes discontinuity adversely affects postoperative hearing. However, this irretrievable sequela is challenging to prove preoperatively, partly because perimatrix inflammation on the pars tensa can obscure the visibility of the ossicles or the partial volume effect of computed tomography (CT) imaging can hamper detailed ossicular visualization. Therefore, there is no consensus regarding the ideal timing for switching from a wait-and-see approach to a surgical one. Herein, we aimed to explore the potential predictors of stapes superstructure destruction in adherent pars tensa. METHODS: This retrospective cohort study enrolled consecutive patients who underwent primary tympanoplasty for adherent pars tensa categorized as grade IV on Sadé's grading scale between April 2016 and September 2021. The impact of features on otoscopy and CT and air-bone gap (ABG) on stapes superstructure destruction was assessed using uni- and multivariable logistic regression analyses. RESULTS: Sixty-four ears were included. Multivariate analysis revealed the presence of debris on the adherent pars tensa (odds ratio [OR] [95% confidence interval {CI}]): 4.799 [1.063-21.668], p = 0.0415), presence of soft-tissue density occupying the oval window (OR [95% CI]: 13.876 [3.084-62.437], p = 0.0006), and a ≥ 20-dB preoperative ABG at 3 kHz (OR [95% CI]: 7.595 [1.596-36.132], p = 0.0108) as independent predictors for stapes superstructure destruction. CONCLUSION: High preoperative awareness of the possibility of destruction of the stapes superstructure would enable the surgeon to make a timely decision to provide surgical intervention before progression to severe stapes destruction, thereby maintaining long-term satisfactory hearing.

Absent Stapedial Tendon: Imaging Features of an Underrecognized Entity : Clinical Neuroradiology.

PURPOSE: Congenital absence of the stapedial tendon is a rare entity with characteristic imaging findings, which can go unrecognized due the scarcity of the diagnosis and limited previous description in the imaging literature. We aim to characterize the imaging features of this entity. METHODS: A series of 9 cases with surgical confirmation of stapedial tendon absence were retrospectively reviewed and the most common abnormalities on high resolution computed tomography (CT) of the temporal bone described. RESULTS: Congenital fixation of the stapes footplate was present in nearly all cases of stapedial tendon absence (n = 8, 89%), a clinically important association because the stapes footplate abnormality was not detectable on preoperative CT. Absence or hypoplasia of the pyramidal eminence and aperture was identified in almost all cases (n = 8, 89%), which may be the sole imaging finding to suggest stapedial tendon absence and associated stapes footplate fixation prior to surgery. CONCLUSION: The most reliable indicator of stapedial muscle absence on temporal bone CT is the absence or hypoplasia of the pyramidal eminence and aperture. Importantly, most patients had congenital stapes footplate fixation confirmed intraoperatively with a normal stapes footplate on CT, meaning the pyramidal eminence/aperture abnormality was the only preoperative imaging finding that could have suggested the footplate fixation.

Three-dimensional quasi-static displacement of human middle-ear ossicles under static pressure loads: Measurement using a stereo camera system.

The time delay and/or malfunctioning of the Eustachian tube may cause pressure differences across the tympanic membrane, resulting in quasi-static movements of the middle-ear ossicles. While quasi-static displacements of the human middle-ear ossicles have been measured one- or two-dimensionally in previous studies, this study presents an approach to trace three-dimensional movements of the human middle-ear ossicles under static pressure loads in the ear canal (EC). The three-dimensional quasi-static movements of the middle-ear ossicles were measured using a custom-made stereo camera system. Two cameras were assembled with a relative angle of 7° and then mounted onto a robot arm. Red fluorescent beads of a 106-125 µm diameter were placed on the middle-ear ossicles, and quasi-static position changes of the fluorescent beads under static pressure loads were traced by the stereo camera system. All the position changes of the ossicles were registered to the anatomical intrinsic frame based on the stapes footplate, which was obtained from µ-CT imaging. Under negative ear-canal pressures, a rotational movement around the anterior-posterior axis was dominant for the malleus-incus complex, with small relative movements between the two ossicles. The stapes showed translation toward the lateral direction and rotation around the long axis of the stapes footplate. Under positive EC pressures, relative motion between the malleus and the incus at the IMJ became larger, reducing movements of the incus and stapes considerably and thus performing a protection function for the inner-ear structures. Three-dimensional tracing of the middle-ear ossicular chain provides a better understanding of the protection function of the human middle ear under static pressured loads as immediate responses without time delay.

Comparison between incus short process and long process coupling of the vibrant soundbridge in human temporal bones.

OBJECTIVE: The Vibrant Soundbridge (VSB) is one of the most widely used implantable hearing devices. It consists of a vibrating floating mass transducer (FMT) that is connected to a middle ear structure. The standard coupling devices for sensorineural hearing loss are short process (SP) or long process (LP) couplers. DESIGN AND STUDY SAMPLE: This study directly compared the electro-mechanical performance of the SP- and LP-coupled FMT of the VSB in the same temporal bone specimen (n = 10). We measured velocity magnitudes and total harmonic distortions (THD) of the stapes (ST) and the round window (RW) using laser Doppler Vibrometry (LDV). RESULTS: Comparison shows a maximally 10 dB higher magnitude for the LP coupler at ST and RW for frequencies below 600 Hz, whereas the SP coupler shows a maximally 20 dB higher magnitude at the ST and RW for frequencies above 600 Hz. THD show similar behaviour with less distortion at 500 Hz for the LP coupler and less distortions for the SP coupler in higher frequencies. CONCLUSIONS: Our experiments showed that the SP coupling may be mechanically favourable, in terms of magnitude and distortion, for the transmission of FMT vibrations at higher frequencies.

Endoscopic transcanal management of incus long process defects: rebridging with bone cement versus incus interposition.

OBJECTIVES: to compare hearing outcomes between endoscopic transcanal rebridging with bone cement and endoscopic transcanal incus interposition in patients with incus long process defects secondary to chronic suppurative otitis media (inactive mucosal type). METHODS: This retrospective study was performed on 83 ears of 83 consecutive patients with incus long process defects secondary to chronic suppurative otitis media (inactive mucosal type). According to the extent of incus long process erosion and subsequent ossiculoplasty technique, patients were divided into 2 groups. Patients in group 1 had erosion involving up to two thirds of the length of the incus long process and underwent endoscopic transcanal rebridging with bone cement. Patients in group 2 had erosion involving more than two thirds of the length of the incus long process and underwent endoscopic transcanal incus interposition. RESULTS: Hearing gain (mean ± standard deviation) was 21.39 ± 2.15 dB in group 1 and 19.71 ± 6.12 dB in group 2. A significantly greater hearing gain was achieved in bone cement group than in incus interposition group (P value < 0.001). Successful hearing outcome (post-operative air bone gap closure within 20 dB) was achieved in 81.6% and 71.1% of patients of group 1 and group 2 respectively. CONCLUSION: Endoscopic transcanal rebridging with bone cement offers greater hearing gain than endoscopic transcanal incus interposition. The two techniques remain reliable and cost-effective techniques in management of patients with incus long process defects. The main limitation of this study was the short follow-up period. Further studies with relatively long-term follow-up are strongly recommended.