Search Results (9)

Background: Stapes prostheses represent one of the earliest and most widely applied “biomedical actuators” designed to restore hearing in patients with otosclerosis. Unlike conventional actuators, which convert energy into motion, stapes prostheses function as passive or smart micro-actuators, transmitting and modulating acoustic energy through the ossicular chain. Objective: This paper provides a comprehensive analysis of stapes prostheses from an engineering and biomedical perspective, emphasizing design principles, materials science, and recent innovations in smart actuators based on shape-memory alloys combined with surgical applicability. Methods: A narrative review of the evolution of stapes prostheses was consolidated by institutional surgical experience. Comparative evaluation focused on materials (Teflon, Fluoroplastic, Titanium, Nitinol) and design solutions (manual crimping, clip-on, heat-activated prostheses). Special attention was given to endoscopic stapes surgery, which highlights the ergonomic and functional requirements of new device designs. Results: Traditional fluoroplastic and titanium pistons provide reliable sound conduction but require manual crimping, with a higher risk of incus necrosis and displacement. Innovative prostheses, particularly those manufactured from nitinol, act as self-crimping actuators activated by heat, improving coupling precision and reducing surgical trauma. Emerging designs, including bucket-handle and malleus pistons, expand applicability to complex or revision cases. Advances in additive manufacturing and middle ear cement fixation offer opportunities for customized, patient-specific actuators. Conclusions: Stapes prostheses have evolved from simple passive pistons to innovative biomedical actuators exploiting shape-memory and biocompatible materials. Future developments in stapes prosthesis design are closely linked to 3D printing technologies. These developments have the potential to enhance acoustic performance, durability, and patient outcomes, thereby bridging the gap between otologic surgery and biomedical engineering. Full article

Background/Objectives: Conductive hearing loss (CHL) recurrence or persistence after stapes surgery is often due to prosthesis displacement or malfunction, with malleus fixation being a less common cause. While persistent CHL linked to malleus fixation can be managed with appropriate diagnosis and surgical intervention, recurrent CHL cases remain poorly documented. This report describes a rare case of recurrent CHL due to malleus neck fixation, likely secondary to surgical trauma. Case Presentation: A 49-year-old woman underwent bilateral stapedectomy. CHL worsened after two years. CT showed right incus erosion and a left bony bridge. Revision surgery corrected the right side. Left tympanotomy revealed malleus fixation from a prior atticotomy. Removing the bony bridge restored ossicular mobility and hearing, stable at 6 and 12 months. Discussion: Malleus fixation after stapedectomy is rare and often related to congenital anomalies, chronic otitis media, tympanosclerosis, or surgical trauma. Bone dust or fragments from surgery may promote new bone formation, causing delayed fixation. Ossicular fixation can develop postoperatively and may be missed during primary surgery. High-resolution CT aids in diagnosis, especially in revision cases, while intraoperative palpation is key to detecting subtle abnormalities. Treatment options include ossicular mobilization, prosthesis revision, or chain reconstruction, tailored to the fixation’s location and severity. Conclusions: Surgical trauma should be considered a potential cause of recurrent CHL post-stapedectomy. Thorough removal of bone debris through aspiration and irrigation during surgery is essential to minimize this risk and optimize long-term hearing outcomes. Full article

This study investigates hearing outcomes of stapedotomy using two different types of prostheses: manually crimped MatriX and thermally activated NiTiBOND. The primary objective was to determine whether the method of prosthesis fixation to the long process of incus influences postoperative results. A retrospective analysis was conducted on 155 patients with otosclerosis; 90 received the NiTiBOND prosthesis and 65 received the MatriX prosthesis. Choice of prosthesis was determined intraoperatively based on position of chorda tympani. If the nerve was located near the incus and the prosthesis fixation site, the surgeon opted for MatriX prosthesis to avoid potential injury from activation of the NiTiBOND. Audiometric evaluations revealed no statistically significant differences in bone conduction thresholds on the first postoperative day (p = 0.275) or at six weeks (p = 0.899), postoperative air-bone gap (p = 0.810), air-bone gap closure (p = 0.489), overclosure (p = 0.436), or bone conduction at 4 kHz (p = 0.324). Chorda tympani nerve injury occurred in 9.2% of cases with MatriX prosthesis and 6.7% with NiTiBOND prosthesis (p = 0.556). Our findings highlight the theoretical and practical significance of comparing both prostheses, demonstrating that NiTiBOND can serve as an alternative in anatomically favorable cases, thereby guiding treatment choices. Full article

Background/Objectives: Long-term prosthetic stability in ossicular chain reconstruction (OCR) surgery may be affected by multiple factors, including prosthesis type. We compared audiometric outcomes including air–bone gap (ABG) and air conduction pure-tone average (AC PTA) over a multi-year period in titanium clip partial prosthetics and other titanium partial and total ossicular reconstruction prostheses. Methods: This was a retrospective study of 92 adult patients (19–74 years) receiving primary, second-look, or revision OCR at a single institution between 2017 and 2021. ABG and AC PTA at short (3–6 months) and long-term (>12 months) postoperative follow-up were compared among patients receiving clip partial prosthetics, traditional PORPs, and TORPs. Results: Overall, AC PTA and ABG were significantly improved in the short term and did not significantly deteriorate in the long term. Clip partial prostheses had significantly lower AC PTAs and ABGs than TORPs in both the short and long term and no difference with PORPs. There was also no significant deterioration in audiometric outcomes in either clip partials, PORPs, or TORPs over time. Clip partials had the highest rate of short- and long-term surgical success (i.e., ABG ≤ 20 dB) with 62.2% and 54.1%, respectively. Cholesteatoma and revision status were not independent predictors of long-term ABG success. Conclusions: The clip partial prosthesis seems to demonstrate similar, and potentially increased, resilience compared to the PORP and TORPs in both the short and long term. They may have comparable effects on audiometric outcomes to PORPs, demonstrating postoperative ABG and AC PTAs that reflect the previous literature. Clip partials appear to be a safe and effective prosthetic for OCR in patients with intact stapes regardless of cholesteatoma or revision status. Full article

Background/Objectives: Stapes surgery is a well-established treatment for conductive hearing loss caused by otosclerosis, with the choice of prosthesis playing a pivotal role in audiological outcomes and safety. Heat-activated and superelastic nitinol prostheses are widely used, but their comparative effectiveness and complication profiles remain debated. This systematic review and meta-analysis aimed to evaluate the audiological outcomes, complication rates, and overall performance of these two prosthesis types. Methods: A systematic review was conducted following PRISMA guidelines. Seven studies involving 273 patients were included. Data on mean air–bone gap (ABG) reduction, complication rates, and follow-up outcomes were extracted. Meta-analyses were performed using a random-effects model, and odds ratios (OR) with 95% confidence intervals (CI) were calculated for comparative analysis. Results: The pooled mean ABG reduction was 20.2 dB (95% CI: 19.47–20.95), indicating substantial and comparable improvements in hearing for both prosthesis types. Heat-activated prostheses achieved slightly higher ABG reduction in individual studies, while superelastic prostheses offered advantages in procedural simplicity. Complication rates were 6.0% for heat-activated and 5.6% for superelastic prostheses. The most common complications included sensorineural hearing loss (2.0–2.4%) and incus-related issues such as necrosis and lateralization. Conclusions: Both prosthesis types provide comparable audiological outcomes and surgical success rates. However, the slightly lower complication rate observed with superelastic prostheses emphasizes their safety and predictability. The choice of prosthesis should be guided by patient anatomy, surgeon expertise, and procedural considerations. Future studies should prioritize long-term outcomes and standardized reporting to further refine prosthesis selection. Full article

Otosclerosis is a pathological condition affecting the temporal bone, and is characterized by remodelling of the labyrinthine bone tissue through a dynamic process of osteolysis and osteogenesis. This condition progressively leads to hearing loss, tinnitus, and vertigo. Stapedotomy, a surgical procedure involving the removal of the stapes superstructure and its replacement with a prosthesis, is the treatment of choice to improve hearing in individuals with otosclerosis. However, vestibular dysfunction is a significant complication associated with this procedure, which can occur intraoperatively or postoperatively, ranging from the immediate postoperative period to weeks, months, or even years after surgery. This paper aims to provide a comprehensive review of the most important causes of vertigo associated with otosclerosis and stapes surgery with the goal of minimizing the incidence of this complication. Understanding the underlying factors contributing to vertigo in this context is crucial for the prevention and effective management of vertigo in patients undergoing stapedotomy. Full article

Background: The persistent stapedial artery (PSA) is a rare congenital vascular malformation involving the middle ear. It is usually associated with pulsatile tinnitus and/or conductive hearing loss and can account for multiple risks during middle ear surgery. Case Report: we present a case of a 9-year-old male child with conductive hearing loss and persistent stapedial artery in his right ear, who was admitted to our ENT Department for hearing loss. During surgery, we discovered PSA along with congenital stapes agenesis and oval window atresia, as well as an abnormal trajectory of the mastoid segment of the facial nerve. After ossicular reconstruction (transcanal total ossicular replacement prosthesis) with cochleostomy, no surgical complications were recorded and hearing improvement was monitored by pre- and postoperative audiometry. Conclusion: Stapedial artery is a rare anatomical middle ear abnormality that can prevent proper surgical hearing restoration and can be associated with other simultaneous temporal bone malformations. Full article

In the case of otosclerosis, it has been noticed that even though there are a variety of different prostheses on the market, due to the anatomical characteristics, it is not always possible to restore excellent mobility to the ossicles and the prosthesis. On the one hand, this happens because the incus long process and the prosthesis create difficult angles. On the other hand, incus necrosis is among the most common causes of the loss of stability to the prosthesis and stapedectomy failure. The aim of this research is to suggest an improvement for stapes prosthesis stability and numerically evaluate the impact of the prosthesis constraining to its dynamical behavior. Numerical 3D models of a standard as well as a modified (adjustable angled) stapes prosthesis were created in order to achieve this aim. Consequently, the modal analysis has been performed to evaluate the mechanical behavior of the prosthesis, assuming that the piston (thick part) would be made of Teflon, and the thin part, fixated on the incus long process, would be made from titanium alloy. Finally, the numerical analysis has been conducted by changing the boundary conditions in respect of the prosthesis constraining, where the attached stapes prosthesis connects to the ossicular chain. Subsequently, there were two hypotheses raised for the prosthesis loop constraining. The first is that during the surgery, the prosthesis is perfectly crimped with certain looseness. The second is that the prosthesis is outgrown by the tissues over time and thus becomes over-constrained. Then, the analyzed standard stapes prosthesis does not fulfil its functions because of the over-constraining that develops over time. An improvement for the standard stapes prosthesis, i.e., a modified stapes prosthesis (adjustable angled), that has been proposed in this research allows avoidance of the negative effects of the over-constrained standard stapes prosthesis that appear over time. Moreover, the proposed modified prosthesis helps to regain hearing when the angle between the incus long process and prosthesis is unfavorable. Full article

Objective: The aim of this study was to evaluate whether stapes prostheses can be visualized with less metal artifacts and therefore more accurately on cone beam computed tomography in comparison to computed tomography imaging. Recent studies have shown that cone beam computed tomography has advantages when imaging metal artifacts. Patients with hearing loss or vertigo, who have undergone stapedotomy, often present a challenge for otologic surgeons. Imaging studies can deliver crucial additional information. Methods: A retrospective analysis of imaging studies and clinical data in a tertiary care center were carried out. Forty-one patients with forty-five implanted ears were evaluated in the study. All included patients had been implanted with a platinum–fluoroplastic (n = 19) or titanium (n = 26) piston and subsequently had undergone imaging months or years after surgery for various reasons. Patients underwent computed tomography or cone beam computed tomography of the temporal bone depending on availability. Piston visualization, prosthesis length, vestibular intrusion and audiologic results were compared between the groups. Piston position on imaging studies were compared to intraoperative findings. Results: Functional length measurements of all prostheses were carried out with a mean error of −0.17 mm (±0.20). Platinum–fluoroplastic protheses were significantly underestimated in length compared to titanium prostheses. To analyze the material-dependent difference in the measurement errors of the imaging techniques the interaction was tested in an ANOVA model and showed no statistically significant result (p = 0.24). The blinded neuroradiologist viewed two implants, both platinum–fluoroplastic pistons, as located outside of the vestibule due to an underestimation of the prothesis length and the missing radiodensity of the lower end of the prosthesis. Conclusion: Surgeons and radiologists should be aware of the different types and radiologic features of stapes prostheses and the missing radiodensity of some protheses parts. Cone beam computed tomography is an imaging alternative with a potential advantage of reduced radiation in patients after stapes surgery suffering from vertigo or hearing loss to evaluate piston position. Full article