Surgical anatomy and pathology of the middle ear

Registration of preoperative temporal bone CT-scan to otoendoscopic video for augmented-reality based on convolutional neural networks

PURPOSE

Patient-to-image registration is a preliminary step required in surgical navigation based on preoperative images. Human intervention and fiducial markers hamper this task as they are time-consuming and introduce potential errors. We aimed to develop a fully automatic 2D registration system for augmented reality in ear surgery.

METHODS

CT-scans and corresponding oto-endoscopic videos were collected from 41 patients (58 ears) undergoing ear examination (vestibular schwannoma before surgery, profound hearing loss requiring cochlear implant, suspicion of perilymphatic fistula, contralateral ears in cases of unilateral chronic otitis media). Two to four images were selected from each case. For the training phase, data from patients (75% of the dataset) and 11 cadaveric specimens were used. Tympanic membranes and malleus handles were contoured on both video images and CT-scans by expert surgeons. The algorithm used a U-Net network for detecting the contours of the tympanic membrane and the malleus on both preoperative CT-scans and endoscopic video frames. Then, contours were processed and registered through an iterative closest point algorithm. Validation was performed on 4 cases and testing on 6 cases. Registration error was measured by overlaying both images and measuring the average and Hausdorff distances.

RESULTS

The proposed registration method yielded a precision compatible with ear surgery with a 2D mean overlay error of 0.65 ± 0.60 mm for the incus and 0.48 ± 0.32 mm for the round window. The average Hausdorff distance for these 2 targets was 0.98 ± 0.60 mm and 0.78 ± 0.34 mm respectively. An outlier case with higher errors (2.3 mm and 1.5 mm average Hausdorff distance for incus and round window respectively) was observed in relation to a high discrepancy between the projection angle of the reconstructed CT-scan and the video image. The maximum duration for the overall process was 18 s.

CONCLUSIONS

A fully automatic 2D registration method based on a convolutional neural network and applied to ear surgery was developed. The method did not rely on any external fiducial markers nor human intervention for landmark recognition. The method was fast and its precision was compatible with ear surgery.

The multifaceted links between hearing loss and chronic kidney disease

Hearing loss affects nearly 1.6 billion people and is the third-leading cause of disability worldwide. Chronic kidney disease (CKD) is also a common condition that is associated with adverse clinical outcomes and high health-care costs. From a developmental perspective, the structures responsible for hearing have a common morphogenetic origin with the kidney, and genetic abnormalities that cause familial forms of hearing loss can also lead to kidney disease. On a cellular level, normal kidney and cochlea function both depend on cilial activities at the apical surface, and kidney tubular cells and sensory epithelial cells of the inner ear use similar transport mechanisms to modify luminal fluid. The two organs also share the same collagen IV basement membrane network. Thus, strong developmental and physiological links exist between hearing and kidney function. These theoretical considerations are supported by epidemiological data demonstrating that CKD is associated with a graded and independent excess risk of sensorineural hearing loss. In addition to developmental and physiological links between kidney and cochlear function, hearing loss in patients with CKD may be driven by specific medications or treatments, including haemodialysis. The associations between these two common conditions are not commonly appreciated, yet have important implications for research and clinical practice.

A Comparative Study of Computed Tomography Findings versus Intraoperative Findings of Level of Tegmen Plate in Chronic Otitis Media: An Observational Study

OBJECTIVE

To compare the computed tomography findings with intraoperative findings of the level of tegmen plate with respect to the superior most part of the lateral semicircular canal in patients with Chronic Otitis Media. This study was attemptted to provide an objective assessment of the level of tegmen mastoideum.

MATERIALS AND METHODS

The level of tegmen plate with respect to the superior most part of the lateral semi-circular canal was measured preoperatively using HRCT scan of slice thickness of 0.6 mm with a software - RadiAnt DICOM Viewer 64-bit version in sagittal plane. The distance between these two planes was measured intraoperatively using micro ear straight pick and Vernier Calipers.

RESULTS

75 participants (thirty-three male & forty-two female) with chronic otitis media underwent computed tomography preoperatively and surgery. No significant difference was found in the height of tegmen measured preoperatively using HRCT temporal bone and intraoperatively (p value - 0.16). The tegmen plates were classified as low lying (2.0 -2.49 mm), intermediate lying (2.49-2.99 mm) and high lying (3.0 -3.49 mm).

CONCLUSION

Computed tomography findings of tegmen height correlates well with the intraoperative findings. An objective assessment of the level of tegmen mastoideum can provide the surgeon an idea of the severity of low lying level of tegmen to be expected and hence likely surgical problems. Based on this study, a classification system of level of tegmen plate has also been proposed.

The Stapes Head Coupler-A Flexible and Safe Option for Vibroplasty

OBJECTIVE

To investigate the surgical approach and the audiological outcome of a stapes head coupler in active middle ear implant surgery.

STUDY DESIGN

Retrospective data analysis.

SETTING

Tertiary referral center with a large active middle ear implant program.

PATIENTS

Twelve patients with active middle ear implant surgery.

INTERVENTIONS

Therapeutic surgical approach for hearing rehabilitation in human subjects.

MAIN OUTCOME MEASURES

Auditory brainstem response, sound field thresholds, vibrogram, speech perception in the Freiburger monosyllabic word test.

RESULTS

The stapes head was attached safely in different coupling situations. Audiological outcomes were similar to the audiological performance of established vibroplasty couplers presented in the literature.

CONCLUSION

The stapes head coupler is a new and safe tool for vibroplasty with a good audiological outcome.

Comparison of the effect of sevoflurane and propofol on the optic nerve sheath diameter in patients undergoing middle ear surgery

PURPOSE

During middle ear surgery, the patient's head is turned away from the surgical site, which may increase the intracranial pressure. Anesthetics also affect the intracranial pressure. The optic nerve sheath diameter (ONSD) measured using ultrasonography is a reliable marker for estimating the intracranial pressure. This aim of this study was to investigate the effect of sevoflurane and propofol on the ONSD in patients undergoing middle ear surgery.

METHODS

Fifty-eight adult patients were randomized into sevoflurane group (n = 29) or propofol group (n = 29). The ONSD was measured using ultrasound after anesthesia induction before head rotation (T0), and at the end of surgery (T1). The occurrence and severity of postoperative nausea and vomiting (PONV) were assessed 1 h after the surgery.

RESULTS

The ONSD was significantly increased from T0 to T1 in the sevoflurane group [4.3 (0.5) mm vs. 4.9 (0.6) mm, respectively; P < 0.001] and the propofol group [4.2 (0.3) mm vs. 4.8 (0.5) mm, respectively; P < 0.001]. No significant difference was observed in the ONSD at T0 (P = 0.267) and T1 (P = 0.384) between the two groups. The change in the ONSD from T0 to T1 was not significantly different between the sevoflurane and propofol groups [0.6 (0.4) mm vs. 0.6 (0.3) mm, respectively; P = 0.972]. The occurrence and severity of PONV was not significantly different between the sevoflurane and propofol groups (18% vs. 0%, respectively; P = 0.053).

CONCLUSION

The ONSD was significantly increased during middle ear surgery. No significant difference was observed in the amount of ONSD increase between the sevoflurane and propofol groups.

Cartilage's Contribution in Otology: A Comprehensive Review of Its Role in Ear Surgery

This comprehensive review thoroughly examines the pivotal role of cartilage in otologic surgery, elucidating its multifaceted contributions to both cosmetic and functional outcomes. From reconstructing the external ear to reinforcing the tympanic membrane and restoring the ossicular chain, cartilage emerges as a versatile and resilient biological material with unique properties that make it an invaluable resource for otologic surgeons. The review explores the nuances of cartilage's applications in various surgical contexts, emphasizing its significance in promoting tissue regeneration and healing. The text delves into advancements in tissue engineering, biodegradable scaffolds, and 3D printing technology, pointing toward a future where more precise and personalized interventions may redefine the landscape of otologic surgery. The convergence of these innovations holds the promise of elevating the standard of care, minimizing complications, and improving the quality of life for patients undergoing cartilage-based otologic procedures. This synthesis of current knowledge and future possibilities provides a valuable resource for otologists, surgeons, and researchers in the dynamic field of otology.

Association of Chronic Otitis Media with Sjogren's Syndrome: A Case-Control Study

There is a paucity of large-scale population-based study whether patients with Sjögren's syndrome are at higher risk of chronic otitis media. This study aimed to investigate the association of chronic otitis media with Sjögren's syndrome by utilizing the representative dataset of the Taiwanese population. We identified 9473 patients with chronic otitis media as cases. We used propensity score matching to select 28,419 controls. We used multiple logistic regression analysis to examine the association of chronic otitis media with prior Sjögren's syndrome after adjusting for age, sex, monthly income category, geographic location and urbanization level of the patient's residence, allergic rhinitis, chronic rhinosinusitis and tonsillitis and adenoiditis. Chi-square tests showed a statistically significant difference in Sjögren's syndrome between patients with chronic otitis media and controls (4.89% vs. 2.93%, p < 0.001). In addition, we found patients with chronic otitis media were more likely to have Sjögren's syndrome (OR = 1.698, 95% CI = 1.509~1.910) relative to controls after adjusting for age, income, geographic location, residential urbanization level, allergic rhinitis, chronic rhinosinusitis and tonsillitis and adenoiditis. We also found that of the male patients, patients with chronic otitis media had a greater tendency to Sjögren's syndrome than controls (adjusted OR = 1.982, 95% CI = 1.584~2.481). Similarly, a statistically significant association between Sjögren's syndrome and chronic otitis media remains in female sampled patients (adjusted OR = 1.604, 95% CI = 1.396~1.842). We found that patients with Sjögren's syndrome were associated with the occurrence of chronic otitis media. It may guide physicians as they counsel patients with Sjögren's syndrome on the possibility of chronic otitis media occurrence.

Structure-constrained deep feature fusion for chronic otitis media and cholesteatoma identification

Chronic suppurative otitis media (CSOM) and middle ear cholesteatoma (MEC) were two most common chronic middle ear disease(MED) clinically. Accurate differential diagnosis between these two diseases is of high clinical importance given the difference in etiologies, lesion manifestations and treatments. The high-resolution computed tomography (CT) scanning of the temporal bone presents a better view of auditory structures, which is currently regarded as the first-line diagnostic imaging modality in the case of MED. In this paper, we first used a region-of-interest (ROI) network to find the area of the middle ear in the entire temporal bone CT image and segment it to a size of 100*100 pixels. Then, we used a structure-constrained deep feature fusion algorithm to convert different characteristic features of the middle ear in three groups as suppurative otitis media (CSOM), middle ear cholesteatoma (MEC) and normal patches. To fuse structure information, we introduced a graph isomorphism network that implements a feature vector from neighbourhoods and the coordinate distance between vertices. Finally, we construct a classifier named the "otitis media, cholesteatoma and normal identification classifier" (OMCNIC). The experimental results achieved by the graph isomorphism network revealed a 96.36% accuracy in all CSOM and MEC classifications. The experimental results indicate that our structure-constrained deep feature fusion algorithm can quickly and effectively classify CSOM and MEC. It will help otologist in the selection of the most appropriate treatment, and the complications can also be reduced.

Noise-Induced Hearing Loss

Noise-induced hearing loss (NIHL) is the second most common cause of sensorineural hearing loss, after age-related hearing loss, and affects approximately 5% of the world's population. NIHL is associated with substantial physical, mental, social, and economic impacts at the patient and societal levels. Stress and social isolation in patients' workplace and personal lives contribute to quality-of-life decrements which may often go undetected. The pathophysiology of NIHL is multifactorial and complex, encompassing genetic and environmental factors with substantial occupational contributions. The diagnosis and screening of NIHL are conducted by reviewing a patient's history of noise exposure, audiograms, speech-in-noise test results, and measurements of distortion product otoacoustic emissions and auditory brainstem response. Essential aspects of decreasing the burden of NIHL are prevention and early detection, such as implementation of educational and screening programs in routine primary care and specialty clinics. Additionally, current research on the pharmacological treatment of NIHL includes anti-inflammatory, antioxidant, anti-excitatory, and anti-apoptotic agents. Although there have been substantial advances in understanding the pathophysiology of NIHL, there remain low levels of evidence for effective pharmacotherapeutic interventions. Future directions should include personalized prevention and targeted treatment strategies based on a holistic view of an individual's occupation, genetics, and pathology.

Audiological outcome after stapes surgery in relation to prosthesis type

PURPOSE

Different techniques are used to fix crimp and CliP® Piston stapes prostheses to the long process of the incus (LPI). The CliP® Piston provides a stiff connection in contrast to the static bended loop of the crimp prosthesis, which imitates the physiological incudostapedial joint (ISJ) and thereby potentially leads to different hearing outcome.

METHODS

In a retrospective single-center study of German-speaking one hundred and ninety patients who underwent stapes surgery CliP® Piston or crimp prostheses between the years of 2016 and 2019 by the same surgeon and in the same setting. Pre- and postoperative bone- (BC) and air-conduction (AC) pure-tone thresholds, pre- and postoperative air-bone gap (ABG) for 0.5, 1, 1.5, 2, 3, 4 kHz and the surgery time were examined.

RESULTS

The postoperative bone conduction thresholds were significantly lower in the frequencies between 0.5 and 3 kHz and the mean ABG was < 10 dB in most cases independent of the prosthesis used. Crimp prosthesis showed a significantly better closure of the ABG at 0.5 kHz.

CONCLUSIONS

The audiological outcome after stapes surgery is dependent on the type of prosthesis used, as reflected by the frequency-specific air-bone gap. The better ABG closure with the crimp prosthesis might be the result of the connection to the LPI imitating the physiological ISJ. The crimp prosthesis may be the better choice if use of hearing aids is expected postoperatively.

Postoperative Anatomical and Functional Success Rates of Pediatric Patients with Chronic Otitis Media: Our Experiences

The preoperative and postoperative pure-tone hearing thresholds and anatomical graft success of pediatric patients who underwent chronic otitis mediasurgery with various indications were evaluated and the factors affecting success were examined.Pediatric patients aged 6 to 18 years, who underwent ear surgery for various reasons between January 1, 2013 and January 1, 2020 were included in the study. All patients included in the sample were assessed in terms of age (< 13 and ≥ 13 years), disease type (cholesteatoma, tympanosclerosis, adhesive otitis media, chronic suppurative otitis media, isolated or traumatic tympanic membrane perforation), surgery performed (type 1 tympanoplasty, canal wall-up mastoidectomy, and exploratory tympanotomy), condition of the contralateral ear (unilateral/bilateral disease), graft material (temporal muscle fascia/tragal cartilage), preoperative and postoperative pure-tone audiometry thresholds and hearing gains, and postoperative sixth-month functional and anatomical graft success. Anatomical graft success and functional success were also evaluated according to the type of surgery performed, type of disease, type of fascia used in surgery, condition of the contralateral ear, and age. No statistically significant difference was found between the groups in terms of anatomical graft success and functional success according to the type of surgery performed (p = 0.414 and p = 0.123, respectively) and type of disease (p = 0.454 and p = 0.097, respectively). There was also no statistically significant difference between the anatomical and functional success of temporal muscle fascia and conchal cartilage grafts (p = 0.833 and p = 0.565, respectively). While no statistically significant difference was observed in graft success between the patients with and without contralateral ear disease, there was a statistically significant difference in functional success (p = 0.188 and p = 0.014, respectively). Although not statistically significant, it was observed that the anatomical graft success rates were decreased in patients with contralateral ear disease compared to those without bilateral disease (p = 0.188). There was no significant difference between age and anatomical graft success (p = 0.865) or functional success (p = 0.956). The type of disease in the diagnosed ear, presence of disease in the contralateral ear, and graft material used affect functional and anatomical graft success rates. Therefore, we believe that pediatric patients should be evaluated considering these factors in the preoperative period and the parents of these patients should be well informed about possible postoperative conditions.

Frailty Is Superior to Age for Predicting Readmission, Prolonged Length of Stay, and Wound Infection in Elective Otology Procedures

OBJECTIVE

To determine the predictive ability of the 5-point modified frailty index relative to age in elective otology patients.

STUDY DESIGN

Retrospective database analysis.

SETTING

Multicenter, national database of surgical patients.

PATIENTS

We selected all elective surgical patients who received tympanoplasty, tympanomastoidectomy, mastoidectomy, revision mastoidectomy, and cochlear implant procedures from 2016 to 2019 from the National Surgical Quality Improvement database.

INTERVENTIONS

Therapeutic.

MAIN OUTCOME MEASURES

Readmission rates, discharge disposition, reoperation rates, and extended length of hospital stay.

RESULTS

Utilizing receiver operating characteristics with area under the curve (AUC) analysis, nonrobust status was determined to be a superior predictor relative to age of readmission (AUC = 0.628 [p < 0.001] versus AUC = 0.567 [p = 0.047], respectively) and open wound infection relative to age (AUC = 0.636 [p = 0.024] versus AUC = 0.619 [p = 0.048], respectively). Nonrobust otology patients were more likely to have dyspnea at rest and an American Society of Anesthesiology score higher than 2 before surgery (odds ratios, 13.304 [95% confidence interval, 2.947-60.056; p < 0.001] and 7.841 [95% confidence interval, 7.064-8.704; p < 0.001], respectively).

CONCLUSION

Nonrobust status was found to be a useful predictor of readmission and prolonged length of stay in patients undergoing elective otology procedures, which generally have low complication rate. Given the aging population and corresponding increase in otology disease, it is important to use age-independent risk stratification measures. Frailty may provide a useful risk stratification tool to select surgical candidates within the aging population.

Exploring Mechanisms Underlying Unexplained Air-Bone Gaps Post-Myringoplasty: Temporal Bone Model and Finite Element Analysis

PURPOSE

Air-bone gap (ABG) is an essential indicator of middle ear transfer function after myringoplasty. However, there is still uncertainty about the mechanisms behind unexplained ABGs in patients post-myringoplasty. The present study investigated these mechanisms using cadaveric temporal bone (TB) measurement and finite element (FE) modeling.

METHODS

Three conditions of tympanic membrane (TM) perforation were modeled with a perforated area of 6%, 24%, and 50% of the total TM area to simulate a small, medium, or large TM perforation of TB model. A piece of paper was used to patch the TM perforation to simulate the situation post-myringoplasty. In the FE model for post-operation, the material properties at the perforation area were changed. Measurement of TM vibration at the umbo was undertaken with a laser Doppler vibrometer (LDV).

RESULTS

As the perforated area increased vibration of the TM at the umbo decreased in both the TB and FE models. But the reduction of TM vibration is more minor in the FE model than in the TB model. After the perforation was repaired, the displacement of TM at the umbo could not be recovered totally in the TB and FE models. In the FE model, the displacement of TM at the umbo decreased markedly when the cone shape of TM flattened, and the reduction was almost the same as that in the TB model in the condition of large perforation.

CONCLUSION

The material properties and the anatomical shape of the repaired TM could influence the TM's modal motion and wave motion. Except for appearance and shape current clinical instruments are unable to resolve factors that affect TM motion. Consequently the ABG seen post-myringoplasty remains unexplained.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumours: Tumours of the Ear

In the recently published 5th Edition of the World Health Organisation Classification of Head and Neck Tumours, there are relatively few changes to report in terms of nomenclature in lesions of ear and temporal bone and fewer developments in molecular pathogenesis in comparison to other sites, particularly in sinonasal tract. Ear and temporal bone tumours are rare and biopsy material is limited. As a result, resources in the literature are scarce with few large series, no controlled clinical trials and the approaches to staging and management are not standardised. New entities are difficult to characterise. The number of entries has, however, increased for tumours of the ear and temporal bone (thirteen) compared to the 4th Edition (eleven). Some lesions previously included in the 4th Edition considered to have no site-specific features have been excluded to be discussed elsewhere and other benign lesions that are specific to this site have been included. The tumours and tumour-like entities of ear and temporal bone are discussed here mindful that the chapter in the 5th edition better correlates disease processes with clinical information and imaging and as far as possible standardises nomenclature.

Tissue engineering and regenerative medicine strategies for the repair of tympanic membrane perforations

Despite the high success rate of autologous grafts in tympanic membrane repair, clinical alternatives are required for the closure of unresponsive chronic perforations that can lead to recurring infection and hearing loss. Tissue engineering and regenerative medicine approaches have emerged as another strategy to repair the eardrum, in addition to negating the need for donor tissue harvest and related surgical iatrogenicities. This review highlights the main approaches using biomaterials, growth factors, and cell therapies towards the healing of complex TM perforations. In addition, we discuss the challenges and advances for the development of reliable animal models, which will allow the optimisation and development of novel techniques. Finally, we indicate technologies that are currently used clinically and others that are closer to the market. The advances here discussed on tissue engineering and regenerative medicine strategies applied to the field of TM perforations will allow otologists, surgeons, and researchers to better bring novel technologies to the bedside as well as to develop new ones.

[Changes in the type and amount of bone collagens in chronic suppurative otitis media]

OBJECTIVE

Comparative assessment of the collagen-tissue interaction in the bone tissue of the middle ear structures in patients with chronic suppurative otitis media (CSOM).

MATERIAL AND METHODS

A prospective study of 42 patients aged 16-60 years with CSOM admitted for reconstructive sanitizing surgery was performed. To study the collagen-tissue interaction, intraoperative samples of the bone tissue of the middle ear were used. A software calculation of vascular-stromal areas and ratios of various types of bone tissue collagen was carried out during histomorphological examination.

RESULTS AND DISCUSSION

The quantitative and qualitative parameters of bone tissue collagen obtained intraoperatively in patients with CSOM were studied. The cavities of the middle ear are in the phase of a chronic purulent process, when the bone structures are morphologically disorganized according to the pathological type, and sclerosis with overgrowth of the cellular structure of the mastoid process is considered a favorable outcome for delimiting the focus of inflammation in the pyramid of the temporal bone.

CONCLUSIONS

Changes in the processes of collagen remodeling of bone structures contribute to the maintenance of inflammation of the middle ear in all clinical forms of CSOM. Pathological osteogenesis can serve as an indicator of the progressive course of a purulent-destructive process in the cavities of the middle ear, which makes it possible to reliably determine the rate of bone tissue transformation to predict relapse after reconstructive and sanitizing surgery.

Evidence of SARS-CoV-2 Virus in the Middle Ear of Deceased COVID-19 Patients

The presence of SARS-CoV-2 in the middle ear reveals the etiopathogenesis of otitis media in COVID-19, as well as an epidemiological risk during otologic examination and surgical procedures in COVID-19 patients. The study included 8 deceased patients with COVID-19. Tissue samples from the middle ear were subjected to virology, histopathology, scanning (SEM) and transmission (TEM) electron microscopy investigation. Ethmoidal mucosa samples were processed for virology analyses. qPCR resulted positive for 75% of nasal mucosa samples and 50% of middle ear samples. Ct values showed lower viral loads in middle ear samples. A proportion of 66.6% patients with positive results in the nasal mucosa showed positive results in the middle ear, and the subtype analysis of the complete genome sequences indicated B.1.1.7 lineage for all samples. In histopathological and SEM samples, no pathological aspects were identified. TEM revealed on the background of death critical alteration of cellular morphology, suggestive structures resembling SARS-CoV-2, goblet cells and immune cells. SARS-CoV-2 can be present in the middle ear of COVID-19 patients even if there is not clinical evidence of acute otitis media. Otolaryngologists could be particularly exposed to COVID-19 infection.

Teaching middle ear anatomy using a novel three-dimensional papercraft model

BACKGROUND

The middle ear is a complex anatomical space which is difficult to interpret from two-dimensional imagery. Appropriate surgical knowledge of the area is required to operate, yet current anatomical teaching methods are costly and hard to access for the trainee.

METHODS

A papercraft 3D design involving anatomical elements added separately to a model was designed, and then peer-validated by medical students and junior doctors. Preliminary quantitative assessment was performed using an anatomical labelling questionnaire, with six students given a lecture to act as a control. Qualitative feedback was also gathered.

RESULTS

18 participants were recruited for the study. A total of 12 models were constructed by 6 medical students and 6 junior doctors. 6 medical students received a lecture only. Qualitative feedback was positive and suggested the model improved knowledge and was useful, yet timing and complexity were issues. Students scored, on average, 37% higher after completing the model, with junior doctors also improving anatomical knowledge, though these differences were not significant (p > 0.05).

CONCLUSIONS

In this initial investigation, the model was shown to be an engaging way to learn anatomy, with the tactile and active nature of the process cited as benefits. Construction of the model improved anatomical knowledge to a greater extent than a classical lecture in this study, though this difference was not significant. Further design iterations are required to improve practical utility in the teaching environment, as well as a larger study.

The Viability and Growth of HaCaT Cells After Exposure to Bioactive Glass S53P4-Containing Cell Culture Media

HYPOTHESIS

Bioactive glass (BG) S53P4 reduces the viability of epidermal keratinocyte-derived immortalized cell line, HaCaT in sufficient concentrations in vitro.

BACKGROUND

Although used in mastoid obliteration surgery, there is no data available on whether BG S53P4 granules have an inhibitory or excitatory effect on keratinocytes, found in normal skin and ear cholesteatoma in vivo.

METHODS

HaCaT cell cultures were incubated with a direct BG S53P4 granule contact. Microscopic evaluation of the cultures was performed and interleukin-6 (IL-6) and -8 (IL-8) concentrations were measured from the medium samples. In addition, BG granules were incubated in two cell culture media for 6 days and the pure media were used in confluent HaCaT cultures preceding cell viability assay. Finally, a scratch assay test was performed to reveal the possible BG effect on HaCaT cultures.

RESULTS

Eight to ten cell thick layers of dead HaCaT cells were noticed after a 2-day BG granule contact. With a BG concentration of 2.5%, IL-6 and IL-8 concentrations were smaller compared with the control group without BG after 2 days' incubation. Overall, HaCaT cell viability decreased when BG was incubated in keratinocyte growth medium, but did not change in Dulbecco's modified Eagle's medium. In a scratch assay test, cell regrowth in the scratch area was notable in cultures without BG.

CONCLUSIONS

BG S53P4 seems to have an inhibitory effect on HaCaT cell growth. Although further studies are needed, this observation seems advantageous for cholesteatoma treatment.

A quick method to expose the structures and relations of the middle ear and inner ear by cadaveric dissection

INTRODUCTION

The temporal bone contains structures related to hearing and balance, and is a valuable learning resource for medical students and trainee surgeons. The middle ear and inner ear are difficult to demonstrate by cadaveric dissection as the structures are closely contained in a small space in the dense temporal bone. Consequently, the teaching and learning of the ear are largely relegated to virtual and theoretical images, and models, which has resulted in a knowledge gap in medical students and prospective surgeons. The present study aimed to elucidate a technique that exposes the structures and relations of the middle and inner ear by cadaveric dissection.

MATERIALS AND METHODS

Forty-seven adult formalin-fixed cadaveric specimens were dissected by the proposed technique. The method was evaluated based on the extent of the structures exposed and time taken for dissection.

RESULTS

The method exposed all the contents and relations of the middle and inner ear, including the course of the facial nerve in the petrous temporal bone, in a few minutes, without use of specialized instruments like saw, drill, endoscope, operating microscope or electric trephine.

CONCLUSION

This dissection method combines maximal exposure of the structures and relations of the middle and inner ear with a short dissection time, sans use of specialized tools. It can be incorporated in the gross anatomy curriculum for medical studentsdue to the short dissection time and completeness of structures exposed. The prosected specimen can also be plastinated for use as a teaching-learning resource for medical students and surgeons.

Foreign Body in the Eustachian Tube: A Challenging Diagnosis and Management

Foreign bodies in the external ear are very common. The same cannot be said about foreign bodies in the Eustachian tube (ET). We report the case of a 63-year-old woman with a history of painless left side otorrhea and hearing loss. She reported a left ear surgery when she was 30-year-old but she did not know the diagnosis that was made at that time neither the kind of surgery performed. Otoscopic examination revealed an inferior perforation of the eardrum. Audiologic evaluation demonstrated a unilateral, moderate-severe mixed hearing loss. Computed tomography scan showed, in left ear, a soft tissue density filling the middle ear cavity and a foreign body in ET. The patient underwent middle ear exploration which required endoscopic assistance to visualize and remove the foreign body. It appeared to be a stapes prothesis of Robinson type. The displacement of a stapes prosthesis to the ET has not been reported in the literature. Surgeries in this region are challenging. This case highlights the importance of the integration of endoscopy into otologic surgery.

Necessities, opportunities, and challenges for tympanic membrane perforation scaffolding-based bioengineering

Tympanic membrane (TM) perforation is a global clinical dilemma. It occurs as a consequence of object penetration, blast trauma, barotrauma, and middle ear diseases. TM perforation may lead to otitis media, retraction pockets, cholesteatoma, and conductive deafness. Molecular therapies may not be suitable to treat perforation because there is no underlying tissue matrix to support epithelium bridging. Chronic perforations are usually reconstructed with autologous grafts via surgical myringoplasty. Surgical treatment is uncomfortable for the patients. The grafting materials are not perfect because they produce an opaque membrane, fail in up to 20% of cases, and are suboptimal to restore acoustic function. Millions of patients from developing parts of the world have not got access to surgical grafting due to operational complexities, lack of surgical resources, and high cost. These shortcomings emphasize bioengineering to improve placement options, healing rate, hearing outcomes, and minimize surgical procedures. This review highlights cellular, structural, pathophysiological, and perforation specific determinants that affect healing, acoustic and surgical outcomes; and integrates necessities relevant to bioengineered scaffolds. This study further summarizes scaffolding components, progress in scaffolding strategies and design, and engenders limitations and challenges for optimal bioengineering of chronic perforation.

Association Between the Air-Bone Gap and Vibration of the Tympanic Membrane After Myringoplasty

Air-bone gap (ABG) is an important indicator of hearing status after myringoplasty. A number of factors have been associated with ABG, but some patients still have ABG without identifiable cause. This study aimed to evaluate the relationship between tympanic membrane (TM) vibration using laser Doppler vibrometry (LDV) and ABG after myringoplasty. Between January 2013 and January 2015, 24 patients with ABG of unknown cause after myringoplasty were enrolled at the Beijing Tongren Hospital. Thirty normal controls were recruited from the hospital staff. All patients underwent primary overlay myringoplasty. Pre- and postoperative air conduction (AC) and bone-conduction (BC) thresholds, and ABG were measured. Umbo velocity transfer function (UVTF) for vibration of TM was measured with LDV. Air conduction thresholds were significantly reduced after myringoplasty (all P < .05), while BC thresholds were not significantly changed (all P > .05). ABG was significantly reduced after myringoplasty (all P < .05). Air-bone gap was correlated with UVTF at 1.0 kHz (r = -0.46; P = .024). For patients with UVTF >0.08 mm/s/Pa, ABG was correlated with UVTF (r = -0.56; P = .029). For post-myringoplasty ABG without readily observable causes, there was a significant relationship between ABG and TM vibration. These results provide new insights in the understanding of this relationship and may help explain ABG after myringoplasty when there are no clear contributing factors.

Oral seeding and niche-adaptation of middle ear biofilms in health

The entrenched dogma of a sterile middle ear mucosa in health is incongruent with its periodic aeration and seeding with saliva aerosols. To test this, we sequenced 16S rRNA-V4 amplicons from otic secretions collected at the nasopharyngeal orifice of the tympanic tube and, as controls, oropharyngeal and buccal samples. The otic samples harbored a rich diversity of oral keystone genera and similar functional traits but were enriched in anaerobic genera in the Bacteroidetes (Prevotella and Alloprevotella), Fusobacteria (Fusobacterium and Leptotrichia) and Firmicutes (Veillonella) phyla. Facultative anaerobes in the Streptococcus genus were also abundant in the otic and oral samples but corresponded to distinct, and sometimes novel, cultivars, consistent with the ecological diversification of the oral migrants once in the middle ear microenvironment. Neutral community models also predicted a large contribution of oral dispersal to the otic communities and the positive selection of taxa better adapted to growth and reproduction under limited aeration. These results challenge the traditional view of a sterile middle ear in health and highlight hitherto unknown roles for oral dispersal and episodic ventilation in seeding and diversifying otic biofilms.

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The middle ear mucosa harbors a rich bacterial community in health.

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Oral migration is the primary mechanism for seeding otic biofilms.

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Periodic aeration of the middle ear enriches for anaerobic taxa and promotes the ecological diversification of oral migrants.

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Our study challenges the entrenched dogma of a sterile middle ear in health.

Computational Optimization of Notch Spacing for a Transnasal Ear Endoscopy Continuum Robot

This paper presents a computational framework to optimize the visual coverage attainable by a notched-tube continuum robotic endoscope inside the middle ear cavity. Our framework combines anatomically-accurate geometric (mesh) models of the middle ear with a sampling-based motion planning algorithm (RRT) and a ray-casting procedure to quantify what regions of the middle ear can be accessed and visualized by the endoscope. To demonstrate the use of this framework, we run computer simulations to investigate the effect of varying the distance between each pair of consecutive flexure elements (i.e., notches) in our robotic endoscope.

Morphological and morphometrical aspects of the auditory ossicles in goat (Capra hircus)

The present paper deals with a detailed description of the auditory ossicles in Capra hircus. The paper focuses on the morphological and morphometrical description of the ossicular assembly, formed by malleus, incus and stapes. The malleus (overall length, as average- 8.16 mm) comprises the head of malleus (Caput mallei), a slightly strictured part-neck (Collum mallei) with 3 distinctive processes (lateral, rostral and muscular) (Processus lateralis, Processus rostralis and Processus muscularis) and a handle (Manubrium mallei). The head of malleus has an oval aspect with an obtuse articular surface on its medial surface (Facies articularis). The neck is evident with three bony processes described-the anterior, almost triangular, the muscular one quite reduced and the lateral one which is the most developed one. The manubrium is the longest sector-4.4 mm and appears as a slightly curved piece. The incus presents a body of 1.3 mm and two processes-the short and long crus (Crus breve and Crus longum). The overall shape of the ossicle resembles a biradicular molar. The lenticular process is a continuation of the distal part of the long crus. The stapes-the smallest in size of the three ossicles (2.7 mm), has a head (Caput stapedis), an anterior (Crus rostrale) and a caudal (Crus caudale) arm and a footplate (Basis stapedis). The two processes are slightly different in size and morphology, delimiting the intercrural space that shows the presence of a bony spicule. The footplate (1.6 mm² area) is ellipsoidal, with an anterior narrower extremity.

Development and Validation of a Clinical Score for Predicting the Risk of Tympanosclerosis Before Surgery

OBJECTIVE

To develop and validate a clinical score to predict the risk of tympanosclerosis before surgery.

METHODS

A sample of 404 patients who underwent middle ear microsurgery for otitis media was enrolled. These patients were randomly divided into 2 cohorts: the training cohort (n = 243, 60%) and the validation cohort (n = 161, 40%). The preoperative predictors of tympanosclerosis were determined by multivariate logistic regression analysis and implemented using a clinical score tool. The predictive accuracy and discriminative ability of the clinical score were determined by the area under the curve (AUC) and the calibration curve.

RESULTS

The multivariate analysis in the training cohort (n = 243, 60%) identified independent factors for tympanosclerosis as the female sex (odds ratio [OR]: 3.83; 95% CI: 1.66-9.37), the frequency-specific air-bone gap at 250 Hz ≥ 45 dB HL (OR: 3.68; 95% CI: 1.68-8.57), aditus ad antrum blockage (OR: 3.29; 95% CI: 1.38-8.43), type I eardrum calcification (OR: 25.37; 95% CI: 8.41-88.91) or type II eardrum calcification (OR: 18.86; 95% CI: 6.89-58.77), and a history of otitis media ≥ 10 years (OR: 4.10; 95% CI: 1.58-11.83), which were all included in the clinical score tool. The AUC of the clinical score for predicting tympanosclerosis was 0.89 (95% CI: 0.85-0.93) in the training cohort and 0.89 (95% CI: 0.84-0.95) in the validation cohort. The calibration curve also showed good agreement between the predicted and observed probability.

CONCLUSIONS

The clinical score achieved an optimal prediction of tympanosclerosis before surgery. The presence of calcification pearls on the promontorium tympani is a strong predictor of tympanosclerosis with stapes fixation.

Navigational guidelines and positional relationships of the human auditory ossicles from three-dimensional topography for ensuring safe and effective malleostapedotomy : Stereotactic topography of the auditory ossicles and its clinical implication

PURPOSE

The aims of the present study were to identify detailed positional relationship between the auditory ossicles and to provide theoretic navigational guidelines for optimal prosthesis adaptation and effective malleostapedotomy.

METHODS

Fifty sides of the temporal bone from donated cadavers were scanned by MicroCT and the malleus, incus, stapes and tympanic membrane were materialized three dimensionally using computer software. Dimensions between the auditory ossicles closely related to malleostapedotomy were measured twice.

RESULTS

The grip site of malleus handle was mean 1.8 mm superior and mean 1.3 mm anterior, and linear distance between the grip site of malleus handle and the footplate of the stapes was mean 6.5 mm. The stapes was not parallel to the tympanic membrane and rotated mean 10.7° posteriorly relative to the tympanic membrane.

CONCLUSION

Surgeons should start with at least 8.75 mm prosthesis to cover the upper limits of potential anatomy and then trim down to the individualization to the case. The ideal loop morphology has to be oval shape more than 1.4 mm in the long diameter and 1.0 mm in the short diameter. The wire of the prosthesis has to be bended at the two points: about 10° anteriorly at the most proximal point of the wire and about 50° superiorly at the stapes head point.

Mechanical Properties of Baboon Tympanic Membrane from Young to Adult

Mechanical properties of the tympanic membrane (TM) play an important role in sound transmission through the middle ear. While numerous studies have investigated the mechanical properties of the adult human TM, the effects of age on the TM's properties remain unclear because of the limited published data on the TM of young children. To address this deprivation, we used baboons in this study as an animal model for investigating the effect of age on the mechanical properties of the TM. Temporal bones were harvested from baboons (Papio anubis) of four different age groups: less than 1 year, 1-3 years, 3-5 years, and older than 5 years of age or adult. The TM specimens were harvested from baboon temporal bones and cut into rectangle strips along the inferior-superior direction, mainly capturing the influence of the circumferential direction fibers on the TM's mechanical properties. The elasticity, ultimate tensile strength, and relaxation behavior of the baboon TM were measured in each of the four age groups with a mechanical analyzer. The average effective Young's modulus of adult baboon TM was approximately 3.1 MPa, about two times higher than that of a human TM. The Young's moduli of the TM samples demonstrated a 26 % decrease from newborn to adult (from 4.2 to 3.1 MPa). The average ultimate tensile strength of the TMs for all the age groups was ~ 2.5 MPa. There was no significant change in the ultimate tensile strength and relaxation behavior among age groups. The preliminary results reported in this study provide a first step towards understanding the effect of age on the TM mechanical properties from young to adult.

Round window accessibility during cochlear implantation

OBJECTIVE

To assess data regarding round window (RW) visibility and surgical approaches in cochlear implant cases, and to describe and analyze surgical steps relevant for the RW approach in cochlear implantation.

STUDY DESIGN

Prospective clinical study.

METHODS

A questionnaire was completed by surgeons after each of altogether 110 cochlear implantations. Round window membrane (RWM) visibility was graded according to the St Thomas Hospital (STH) classification.

RESULTS

Performing different surgical steps during the preparation of the RW niche, the RWM could be fully exposed (STH Type I) in 87%. A RW approach could be used for electrode insertion in 89% of the adult and 78% of the pediatric cases. The distribution of RW types differed significantly between adults and children. Drilling of the superior bony lip was the surgical step most frequently needed in adult as well as pediatric cases to obtain optimal RW exposure.

CONCLUSION

In children, optimized surgical exposure of the RW niche resulted in only 52% full RWM visibility; whereas in adults, this could be achieved in 87%. The facial nerve (FN) had to be exposed at the level of the posterior tympanotomy in more than 70% of pediatric cases with full RWM visibility; while in adult cases with 100% visibility, such specific exposure was necessary in only 33%. Thus, surgical preparation of the RW niche seems to be more demanding in children than in adults.

Grading of the Position of the Mastoid Tegmen in Human Temporal Bones - A Surgeon's Perspective

OBJECTIVES

To establish a new surgically relevant classification system of the anatomic variations of the temporal bone tegmen plate as well as to perform a comparative analysis, with respect to the pneumatization patterns in the cadaveric temporal bones.

MATERIALS AND METHODS

Microdissection of the human cadaveric temporal bones was performed after obtaining ethical approval from the Institutional Ethical Committee (F.8-522/A-522/2017/RS). The pneumatization pattern of the temporal bones was noted as "under-pneumatized" or "well-pneumatized." The tegmen mastoid (TM) was classified into two grades as per the position of the tegmen plate and the visibility of the superior semicircular canal (SSCC) and the aditus. The latter two structures were well visualized in Grade A and poorly visualized in Grade B. The data were analyzed using Stata 14.0 (Stata Corp, 4905, Lakway drive, College Station, Texas, USA).

RESULTS

Ninety-three temporal bones were dissected under microscope. Fifty-eight bones were well-pneumatized and 35 were under-pneumatized. The tegmen plates were classified as Grade-A in 49 bones (well-pneumatized -37 and under-pneumatized -12), and as Grade-B in 44 bones (well-pneumatized-21, poorly-pneumatized-23). Grade-A classification was significantly more common in well-pneumatized temporal bones, while Grade-B was more common in under-pneumatized bones (p=0.0057).

CONCLUSION

We propose a surgically relevant classification for TM positioning. A well-pneumatized temporal bone is associated with a significantly higher position of the tegmen plate (Grade-A TM).

Bilateral Oval and Round Window Atresia on CT Temporal Bone: A Rare Anomaly Clinically Mimicking Otosclerosis in an Adult

We present a rare adult case of bilateral oval and round window atresia. Clinical and audiologic findings were suggestive of otosclerosis. High resolution CT Temporal bones showed unequivocal findings of bilateral oval and round window atresia. Atresia of these windows is a rare temporal bone anomaly. Presentation as an adult can confound the clinicians and warranting a closer look on the CT for atretic windows and subtle signs of otosclerosis in patients with conductive hearing loss.

Identification of early inflammatory changes in the tympanic membrane with Raman spectroscopy

The tympanic membrane (TM) is a dynamic structure that separates the middle ear from the external auditory canal. It is also integral for the transmission of sound waves. In this study, we demonstrate the feasibility of using Raman spectroscopy to identify early chemical changes resulting from inflammation in the TM that can serve as an indicator of acute otitis media. Bacterial lipopolysaccharide (LPS) was injected trans-tympanicaly in a murine model. Presence of inflammatory response was assessed with binocular microscopy, confirmed with histopathology and immunofluorescence staining. Successful discrimination suggesting spectral differences among the control and LPS treated groups was achieved using principal component analysis. Raman imaging revealed major differences in collagen distribution and nucleic acid content. Image segmentation analysis on the trichrome stained tissue sections was performed to corroborate the Raman spectra. The spectral co-localization study suggests changes in the expression of collagen IV specific signals in LPS treated samples. The overall findings of the study support prospective application of RS in the diagnosis and therapeutic monitoring of otitis media.

How Stapes Ankylosis and Fracture Affect Middle Ear Dynamics: A Numerical Study

Numerical models of the human middle ear have been developed throughout the last 30 years, for different purposes. While several types of pathologies have been studied, stapedial disorders were seldomly explored. This papers aims to clarify how stapes fracture and some forms of stapes ankylosis, such as stapedial tendon (ST) ossification, augmented pyramidal eminence (PE) and bony bar presence, affect the sound transmission through the middle ear. In addition, the stapes dynamics is also analyzed by means of total displacement and first principal strain. For the purpose of the study, first, a three-dimensional finite element model of the human middle ear is detailed and validated under normal (healthy) conditions. The model is then modified to represent the stapedial disorders of interest. A measure is established for evaluating how the disorders reduce sound transmission through the middle ear. Results of the reduction of sound transmission showed that the different forms of stapes ankylosis affect primarily low frequencies, while the stapes fracture mostly affects high frequency sound transmission. According to the results, an augmented PE does not restrict stapes movement unless followed by some ossification of the ST. In addition, the question whether the fracture is in the anterior or posterior crus and the distance of the fractured part from the stapes footplate have a relevant role in the reduction of the sound transmission. Finally, the analysis of total displacement and first principal strain of the stapes helped to highlight some differences among the stapedial disorders.

The diagnostic accuracy of 1.5 T versus 3 T non-echo-planar diffusion-weighted imaging in the detection of residual or recurrent cholesteatoma in the middle ear and mastoid

PURPOSE AND BACKGROUND

This study retrospectively compares diagnostic performance of 1.5 T versus 3 T non-echo planar diffusion weighted imaging with or without additional T1 and T2 sequences in the detection of residual and/or recurrent cholesteatoma.

METHODS

Patients with clinically suspected recurrent cholesteatoma or postoperative routine survey MR who subsequently underwent surgical procedure were retrospectively included (135 patients, 164 operated ears) from a large database. Patients underwent 1.5 T (128 ears) or 3 T MRI (36 ears), with non-echo planar DWI, T1 and T2 acquisitions. Two radiologists independently reassessed the images. Definitive surgical diagnosis was used as gold standard. Sensitivity, specificity and diagnostic odds ratio were evaluated.

RESULTS

According to surgical diagnosis a cholesteatoma was present in 124 of 164 ears, corresponding with a prevalence of 75%. Sensitivity and specificity were lower for 3 T compared to 1.5 T, irrespective of whether additional T1 and T2-weighted sequences were used or not. Diagnostic odds ratios were higher for 1.5 T (34 and 12 for reader 1 and 2, respectively) compared to 3 T (3 and 4 for reader 1 and 2, respectively). Adding T1 and T2 sequences lowers sensitivity but increases specificity.

CONCLUSION

Non-epi DWI for the detection of residual/recurrent cholesteatoma is preferably performed on 1.5 T scanners over 3 T. The use of additional sequences regarding detection of cholesteatoma is debatable as it lowers sensitivity but increases specificity. However, these sequences may also be of use in diagnosing complications and planning surgical procedures in some hospitals.

Post-myringotomy oto-liquorrhea in children - A case study and literature review

Myringotomy is a surgical incision of tympanic membrane used mainly as therapy for acute otitis media. It is a safe and simple procedure; however possible complications must be considered. In this article is described a case study of a 2-and-a-half-year-old girl with a massive oto-liquorrhea following myringotomy.

Surgical anatomy of the round window-Implications for cochlear implantation

BACKGROUND

The round window is an important portal for the application of active hearing aids and cochlear implants. The anatomical and topographical knowledge about the round window region is a prerequisite for successful insertion for a cochlear implant electrode.

OBJECTIVE OF REVIEW

To sum up current knowledge about the round window anatomy and to give advice to the cochlear implant surgeon for optimal placement of an electrode.

TYPE OF REVIEW

Systematic Medline search.

SEARCH STRATEGY

Search term "round window[Title]" with no date restriction. Only publications in the English Language were included. All abstracts were screened for relevance, that is a focus on surgical anatomy of the round window. The search results were supplemented with hand searching of selected reviews and reference lists from included studies.

EVALUATION METHOD

Subjective assessment.

RESULTS

There is substantial variability in size and shape of the round window. The round window is regarded as the most reliable surgical landmark to safely locate the scala tympani. Factors affecting the optimal trajectory line for atraumatic electrode insertion are anatomy of the round window, the anatomy of the intracochlear hook region and the variable orientation and size of the cochlea's basal turn.

CONCLUSIONS

The very close relation to the sensitive inner ear structures necessitates a thorough anatomic knowledge and careful insertion technique, especially when implanting patients with residual hearing. In order to avoid electrode migration between the scalae and to achieve protect the modiolus and the basilar membrane, it is recommended to aim for an electrode insertion vector from postero-superior to antero-inferior.

Dynamic property changes in stapedial annular ligament associated with acute otitis media in the chinchilla

Located at the end of the ossicular chain, the stapedial annular ligament (SAL) serves as a closed yet mobile boundary between the cochlear fluid and stapes footplate. It is unclear how SAL properties change with acute otitis media (AOM). This paper reports the measurements of SAL dynamic properties in chinchilla AOM model using dynamic mechanical analyzer (DMA) and frequency-temperature superposition (FTS) principle. AOM was analyzed in two infection groups: 4 days (4D) and 8 days (8D) post induction. SAL specimens were measured using DMA at three temperatures: 5, 25, and 37°C. To extend the testing frequencies to higher levels, FTS principle was employed. Then generalized Maxwell model was utilized to define the constitutive equations of the SAL. The complex shear moduli were obtained from seven samples of control, 4D, and 8D groups. Results show that the storage and loss shear moduli of SALs decreased due to AOM. The storage moduli for 4D and 8D ears were similar below 100Hz, and the loss modulus for 4D was significantly larger than 8D across the entire frequency range. This study reports data that contributes to ear biomechanics and improves understanding on the effects of AOM in middle ear tissues.

Anatomic Eponyms in Neuroradiology: Head and Neck

In medicine, an eponym is a word-typically referring to an anatomic structure, disease, or syndrome-that is derived from a person's name. Medical eponyms are ubiquitous and numerous. They are also at times controversial. Eponyms reflect medicine's rich and colorful history and can be useful for concisely conveying complex concepts. Familiarity with eponyms facilitates correct usage and accurate communication. In this article, 22 eponyms used to describe anatomic structures of the head and neck are discussed. For each structure, the author first provides a biographical account of the individual for whom the structure is named. An anatomic description and brief discussion of the structure's clinical relevance follow.

Tympanosclerosis Presenting as Mass: Workup and Differential

Introduction. Tympanosclerosis is a commonly encountered entity within ENT clinics and primary care settings. Recognizing ear pathology is essential for correct management. Oftentimes the diagnosis is clear; however in certain cases further workup to rule out other more insidious disease processes is warranted. Case Report. We present a case of tympanosclerosis which presented as an ear mass without classic appearance of tympanosclerosis. Through imaging and biopsy the diagnosis of tympanosclerosis was made. The patient was treated surgically with good outcome. Discussion. Various ear pathologies, with different treatment algorithms, may present as clinically similar to one another. Differential diagnosis for this case included tympanosclerosis, cholesteatoma, or other middle ear masses. We review these entities and discuss their pathophysiology and implications on management.