A Peculiar Case of Isolated Bilateral Tympanic Plate Fractures.

Tympanic plate fractures are uncommon injuries and carry the risk of external auditory canal stenosis. These injuries are often associated with fractures of adjacent bones like the mandible, maxilla, and temporal bone. Isolated bilateral tympanic bone fractures have rarely been reported. The most frequently advocated treatment for these injuries is surgical to prevent canal stenosis in the future. The effectiveness of non-operative management has been seldom reported. In the current case report, we present an uncommon injury with isolated bilateral tympanic plate fractures secondary to trauma to the mandible with no associated mandible or condylar fractures that were treated non-operatively. The functional outcomes were favorable at one year of follow-up.

The effective surgical management of traumatic external auditory canal atresia resulting from a dog bite using a stent silicone prosthesis.

INTRODUCTION: Acquired external auditory canal (EAC) atresia is a very rare condition, especially due to direct trauma. The challenge lies in the difficulty of treatment and the tendency to recur even after a long period. Here we present a case report of treatment of recurrent EAC atresia resulting from a dog bite using a silicone stent prosthesis. CASE PRESENTATION: A 4-year-old, bitten by a dog, suffered severe head injuries, including scalp avulsion and left auricle avulsion. Initial treatment included wound closure, antibiotics, and vaccines. However, complications arose, leading to left EAC atresia and hearing loss. Surgical interventions, including canaloplasty and skin grafting, were conducted, with recurrence prompting second surgery with using a silicon prosthetic post-surgery. Follow-up for up to 14 months showed no evidence of recurrence of atresia, with complete improvement in hearing. DISCUSSION: Acquired stenosis of the External Auditory Canal (EAC) can result from various factors, predominantly otitis externa and traumatic incidents, including previous surgeries. Though direct trauma is rare, it can lead to stenosis. Surgical intervention is often necessary for post-traumatic cases, involving removal of obstructions, canal widening, and reconstruction. Management depends on maturity of stenosis, with non-surgical methods for soft stenoses and surgical procedures for mature ones, often supplemented by postoperative stents to preventing restenosis. CONCLUSION: Acquired external auditory canal atresia remains a rare, difficult-to-treat entity with a high rate of recurrence. The use of a silicone prosthesis stent after surgery can be considered an effective method in preventing recurrence.

Surgical Option for External Auditory Canal Cholesteatoma: A Case Report.

External Auditory Canal Cholesteatomas (EACC), is an exceptionally rare condition with a prevalence of only 0.1-0.5% among new patients1. EACC are known to possess bone eroding properties, causing a variety of complications, similar to the better-known attic cholesteatomas. We describe here the novel surgical management of a case of EACC. She is 38-year-old female who presented with otorrhea for 6 months. Clinical examination and radiological investigations suggested the diagnosis of an external auditory canal cholesteatoma. The patient underwent modified radical mastoidectomy with type 1 tympanoplasty with meatoplasty. Post-operatively, the patient showed marked clinical improvement.

Inverted Follicular Keratosis: A Rare Presentation in External Ear Canal.

Inverted follicular keratosis is a benign skin lesion that typically presents as an asymptomatic, solitary nodule that may mimic malignant lesions, especially squamous cell carcinoma, both clinically and pathologically. It is developed from the hair follicle infundibulum and can be considered a variant of seborrheic dermatitis. We present a case of a 26-year-old gentleman with a soft tissue mass at the external auditory canal which was later confirmed as inverted follicular keratosis and was treated by endoscopic transcanal excision of the mass with temporalis fascia graft reconstruction. He is currently under surveillance follow-up with no symptoms and signs of recurrence.

Relapsing Irritated Seborrheic Keratosis of External Auditory Canal and its Management.

Seborrheic keratosis lesions are tumors that rarely occur in the external auditory canal. There are several histological variants, and one of them is the irritated seborrheic keratosis. This kind has been scarcely reported in the literature. We report a 62 years old man with this lesion that relapses after monopolar electrocautery, and finally is removed by skin flap dissection.

Xanthogranuloma in the External Auditory Canal in Childhood, an Unexpected Lesion.

Pedunculated lesions in the external auditory canal present a broad differential diagnosis. It is crucial to rule out malignant neoplasms and consider the possibility of xanthogranulomas, which are very rare in this location. Management is determined by associated complications, and otolaryngologists must consider this for appropriate treatment.

Fungal Otitis Externa (Otomycosis) Associated with Aspergillus Flavus: A Case Image.

A 48-year-old man presented with a chief complaint of intermittent right ear otorrhea of several-month duration, occasional otalgia and progressive unilateral hearing impairment. He also reported frequent episodes of headache and pressure in the sinuses and maxilla. Previous systemic treatment with antibiotics failed to alleviate the symptoms. A head/neck CT showed completely normal mastoid, middle ear and external auditory canal regions without any evidence of opacification or bone erosion. Otoscopic examination of the right ear disclosed aggregates of dried, brown, fibrillar material and debris occluding the external auditory canal and obstructing the otherwise intact tympanic membrane. Dilation of the external auditory canal or thickening of the tympanic membrane were not appreciated. The canal was debrided and the fibrillar material was placed in formalin. Histopathologic examination revealed numerous branching, septated fungal hyphae organized in densely-packed clusters. In other areas, the fungal hyphae abutted or were attached to lamellated collections of orthokeratin. As highlighted by GMS staining, the fungi were morphologically compatible with Aspergillus species. The clinicopathologic findings supported a diagnosis of fungal otitis externa, while the numerous anucleate squamous cells were compatible with colonization of an underlying, probably developing, cholesteatoma. Culture of material isolated from the external auditory canal confirmed the presence of Aspergillus flavus. In this illustrative case, we present the main clinical and microscopic characteristics of Aspergillus-related otomycosis developing in the setting of a tautochronous cholesteatoma.

Finding the Silver Bullet for Persistent Foramen Hushke.

We report a case of persistent foramen Hushke and embark on a literature search from 1990 to 2021. The search was done using electronic databases of PubMed and Google Scholar using the MESH words 'TMJ herniation', 'persistent foramen Hushke', 'TMJ prolapse', 'EAC dehiscence', and 'ear canal mass'. A total of 37 other case reports were included after excluding duplicates and non-English publications. The most common presentations, treatment modalities, complications, and outcomes were discussed. Common presentations include otalgia, tinnitus, otorrhea, and aural fullness. Surgical intervention shows a good outcome, whereas conservative treatment shows a mixed response. Despite the overwhelming success of surgical interventions in treating symptomatic persistent foramen of Hushke, it is still early to establish a guideline to manage these patients, as this condition is rare and presents with variable symptoms. More high-quality studies and a long-term follow-up of the patients may be essential to observe and compare the outcome and recurrence rate of temporomandibular joint (TMJ) herniation.

Treatment outcome and prognostic factors of external auditory canal squamous cell carcinoma: A retrospective study in a tertiary center.

Objective: Squamous cell carcinoma (SCC) of the external auditory canal (EAC) is a rare malignancy with various treatment strategies and outcomes. The purpose of this study was to evaluate the clinical characteristics and survival outcomes and identify prognostic factors in patients with SCC of EAC. Methods: Twenty-one patients with SCC of EAC treated in a single tertiary center between 2009 and 2021 were retrospectively reviewed and analyzed. The modified Pittsburgh classification system was applied for staging. Factors associated with survival were identified by univariate survival analysis. Results: The mean age at diagnosis was 61 years (range: 41-79 years). Early-stage (T1 + T2) accounts for 38.1% of the series and advanced-stage (T3 + T4) accounts for 61.9%. Eighteen (85.7%) patients underwent primary surgery with curative intent. The 5-year overall survival rate of the 21 patients was 67.4%. Tumor invasion to the otic capsule, eustachian tube, sigmoid sinus, and dura were associated with poor prognosis in univariate analysis (p = .046; .008; .027; and .08, respectively). Conclusions: Factors predictive of less favorable survival include the history of COM, tumor invasion to the otic capsule, eustachian tube, sigmoid sinus, and dura. It is important to make a precise and systemic preoperative evaluation of disease extent. Level of Evidence: 4.

Carcinomas of the external auditory canal: Management and results: A multicenter REFCOR propensity score matching study.

OBJECTIVES: To analyse prognostic factors and survival outcomes of malignant tumors of the external auditory canal, to investigate the role of regional surgery, and adjuvant radiotherapy in early stages and to investigate the role of surgery in operable T4 stage. SETTING: A retrospective analysis was conducted on all patients prospectively included in the national database of the French Expertize Network for Rare ENT Cancers (REFCOR) from January 2000 to December 2016. PARTICIPANTS: 103 patients from 19 reference centers were included. A propensity score matching analysis was applied to enable comparisons between treatments. MAIN OUTCOMES AND MEASURES: Event-free survival, overall survival and factors of poor prognosis of the cohort were described. The interest of local and regional surgery and postoperative radiotherapy were evaluated. RESULTS: The factors of poor prognosis on event-free survival were immunosuppression (p = 0.002), Karnofsky status less than 90% (p = 0.02), body mass index less than 19 Kg / m2 (p = 0.0009), peripheric facial palsy (p = 0.0016), and positive margin (p = 0.0006). In early stages, locoregional surgery was associated with an increase in event-free survival (p = 0.003, HR = 0.21) versus local surgery alone, while postoperative radiotherapy was not associated with an increase in event-free survival (p = 0.86, HR = 0.91) or overall (p = 0.86, HR = 0.91). In locally advanced stages, locoregional surgery followed by radiotherapy was associated with an increase in event-free survival (p = 0.03, HR = 0.39) and overall (p = 0.02, HR = 0.34) versus chemoradiotherapy alone. CONCLUSION AND RELEVANCE: Regional surgery is recommended for early stages of cancers of the external auditory canal. In operable cases, locoregional surgery followed by radiotherapy is recommended.

Questioning the value of stalk drilling after external auditory canal osteoma excision: case series, literature review, and meta-analysis.

OBJECTIVES: To question the value of drilling the site of the stalk ("insertion site" or "stalk" drilling) of a pedunculated external auditory canal osteoma (EACO) in reducing recurrence. DATA SOURCES: A retrospective medical chart review of all patients treated for EACO in one tertiary medical center, a systematic literature review using Medline via "PubMed", "Embase", and "Google scholar" search, and a meta-analysis of the proportion for recurrence of EACO with and without drilling. RESULTS: The local cohort included 19 patients and the EACO origin was the anterior EAC wall in 42% and the superior EAC wall in 26%. The most common presenting symptoms were aural fullness and impacted cerumen (53% each), followed by conductive hearing loss (42%). All patients underwent post-excision canaloplasty, and one sustained EACO recurrence. Six studies suitable for analysis were identified (63 EACOs). Hearing loss, aural fullness, otalgia, and cerumen impaction were the most common clinical presentations. The most common EACO insertion site was the anterior EAC wall (37.5%), followed by the superior EAC and posterior walls (25% each). The inferior EAC wall was least affected (12.5%). There was no significant difference in recurrence between EACOs whose stalk insertions were drilled (proportion 0.09, 95% confidence interval [CI] 0.01-0.22) to the ones whose insertion was not drilled (proportion 0.05, 95% CI 0.00-0.17). The overall recurrence proportion was 0.07 (95% confidence interval 0.02-0.15). CONCLUSION: EACO insertion site drilling does not reduce recurrence and should be avoided in the absence of a definite pedicle projecting to the EAC lumen.

Temporomandibular joint herniation into the external auditory canal presenting as clicking tinnitus: A case report.

BACKGROUND: Herniation of the temporomandibular joint (TMJ) into the external auditory canal (EAC) due to a bony defect in the EAC is rare. Such bony defects can be secondary to inflammation, neoplasm, trauma. In rare instances, TMJ herniation can occur when the Huschke foramen is constantly exposed. TMJ herniation can induce clicking tinnitus, otalgia, conductive hearing loss, and otorrhea, but can also present with no symptoms. This study reports a case of TMJ herniation. CLINICAL PRESENTATION: A male patient presented with clicking tinnitus that had developed 3 years ago. Dome-shaped soft tissue was found on the anterior EAC wall, which protruded and depressed with mouth movement. The patient underwent surgical reconstruction of the bony defect with titanium mesh, and the symptoms resolved after surgery. CONCLUSION: This case highlights the importance of surgical reconstruction of a bony defect in the EAC using appropriate materials.

Risk Factors for Locoregional Recurrence and Distant Metastasis in 143 Patients with Adenoid Cystic Carcinoma of the External Auditory Canal.

AIMS: Adenoid cystic carcinoma (ACC) grows slowly and is characterised by potential recurrence and metastasis to distant organs. This study aimed to evaluate the risk factors for locoregional recurrence (LRR) and distant metastasis in patients with ACC of the external auditory canal (EAC). MATERIALS AND METHODS: Demographic, pathological, therapeutic and survival data of 143 patients with EAC ACC were reviewed in this study. Univariate and multivariate Cox proportional hazard regression analyses were carried out to determine the risk factors for LRR and distant metastasis. Factors associated with overall survival after LRR and distant metastasis were also analysed. RESULTS: During a median follow-up of 49 months, 31 of 143 patients were observed with LRR and 34 developed distant metastasis. Bone invasion and histological subtype were independent risk factors for locoregional recurrence-free survival. T stage and LRR were independent risk factors for distant metastasis-free survival. Salvage surgery and adjuvant radiotherapy or chemoradiotherapy for LRR resulted in better survival, whereas extrapulmonary metastasis and LRR were associated with a higher risk of poor survival after distant metastasis. CONCLUSION: Patients with distant metastases, especially those with LRR, are at significant risk of poor prognosis. Our findings emphasise the importance of long-term regular follow-up and recommend surgical intervention with radiotherapy for recurrent EAC ACC.

The Role of Parotid Gland Invasion in Adenoid Cystic Carcinoma of the External Auditory Canal.

OBJECTIVE: This study aimed to investigate the significance of parotid gland invasion in predicting distant metastasis of adenoid cystic carcinoma in the external auditory canal. STUDY DESIGN: Single-institution retrospective cohort study. METHODS: A retrospective review of patients with adenoid cystic carcinoma of the external auditory canal who underwent surgery was performed. Information on patient demographics, parotid gland invasion, tumor stage, perineural invasion, lymphovascular invasion, and follow-up data were collected and analyzed. RESULTS: One hundred twenty-nine patients were identified for review. Parotid gland invasion was noted in 45 patients (34.9%). Parotid gland invasion was significantly associated with tumor stage, perineural invasion, distant metastasis, and postoperative adjuvant therapy. Distant metastasis was noted in 30 patients (23.3%). Multivariate Cox proportional hazards analysis identified parotid gland invasion as an independent risk factor for predicting distant metastasis. The 5-year distant metastasis-free survival rate was 83.6% for patients without parotid gland invasion and 61.8% for patients with parotid gland invasion (p = 0.010). CONCLUSIONS: The parotid gland invasion rate is relatively high in adenoid cystic carcinoma of the external auditory canal and is significantly related to tumor stage. Parotid gland invasion is associated with worse distant metastasis-free survival. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:419-425, 2024.

Hyaluronic Acid Gel as Middle Ear and External Auditory Canal Packing Material in Tympanoplasty.

OBJECTIVE: This study aims to evaluate the effect of hyaluronic acid gel (HAG) on tympanic membrane (TM) graft success rate and audiometric outcomes in patients with large TM perforations during tympanoplasty. STUDY DESIGN: A single-blinded randomized controlled trial. SETTING: Tertiary hospital. METHODS: In the study, we performed tympanoplasty via postauricular approach on 488 ears and compared 2 groups: the control group (n = 247) with absorbable gelatin sponge packing and the HAG group (n = 241) with HAG packing in both the middle ear and medial 2/3 of the external auditory canal. We compared the graft success rates and postoperative audiometric outcomes between the 2 groups. RESULTS: In a study of 488 ears (HAG group = 241, control group = 247), the HAG group had a higher graft success rate of 96.7% (233/241 ears) compared to the control group's 91.5% (226/247 ears; P = .015). No significant difference was observed between HAG and control in postoperative ABG closure within 20 dB (HAG: 66.8% or 161 ears; control: 59.1% or 146 ears; P = .078). There were no significant differences in improvements, compared to their preoperative condition, in mean bone conduction (HAG: -0.1 ± 6.5; control: 1.3 ± 7.6), air conduction (HAG: 8.7 ± 12.1; control: 9.7 ± 13.1), air-bone gap (HAG: 8.8 ± 10.6; control: 8.4 ± 12.0), and speech reception threshold (HAG: 9.4 ± 11.8; control: 9.2 ± 13.5) between the control and HAG groups (two one-sided T test, P < .001). CONCLUSION: In tympanoplasty, HAG packing in the middle ear and external auditory canal yields higher graft success rates than absorbable gelatin sponge, while audiometric outcomes are similar for both the HAG and absorbable gelatin sponge packing cohorts.

Treatment of external auditory canal stenosis and atresia after transcanal endoscopic ear surgery.

PURPOSE: To discuss the treatment of external auditory canal stenosis or atresia occurring as a complication of transcanal endoscopic ear surgery. MATERIALS AND METHODS: We retrospectively analyzed the medical records of 11 patients who developed external auditory canal stenosis or atresia after undergoing transcanal endoscopic ear surgery. The 10 patients with stenosis were treated with external auditory canal expansion via drainage tube insertion; 2 of these patients further received local injections of triamcinolone acetonide. One patient with atresia was treated with meatoplasty surgery followed by tube insertion and triamcinolone acetonide injection. RESULTS: The stenosis/atresia improved in all patients, and the external auditory canal was unobstructed without restenosis. CONCLUSIONS: Stenosis/atresia of the external auditory canal after transcanal endoscopic ear surgery should be treated with dilation therapy/meatoplasty in a timely manner to prevent progressive hyperplasia of the scar and regain a normal-sized ear canal.

Evaluation of the Sigmoid Sinus Morphology by Cone Beam Computed Tomography; Touchstone of the Posterior Cranial Fossa.

OBJECTIVE: In this study, we aimed to analyze the relationship of the sigmoid sinus (SS) with the external auditory canal, facial nerve, and mastoid cells from an anatomic point of view, to define the position of the SS during transmastoid, translabyrinthine, retrosigmoid (lateral suboccipital) approaches, in tympanomastoidectomy and posterior cranial fossa surgery. METHODS: In this study, the morphologic structures associated with the sigmoid sinus were evaluated in cone beam computed tomography images taken between 2015 and 2022. The images of 68 men and 106 women, aged 18-65 years, obtained from the archive of Ankara University Faculty of Dentistry, Department of Oral and Maxillofacial Radiology were analyzed. RESULTS: The most common SS pattern was type II, with a rate of 60.8% (n = 209); the second was type III, with 20.6% (n = 71); and the least common was type I, with 18.6% (n = 64). Although the distance between the horizontal line passing through the external auditory canal and facial nerve and the anterior contour of the SS was highest in type I (right, 7.26 ± 1.62; left, 7.44 ± 0.97), it was lowest in type III (right, 4.40 ± 1.50; left, 4.84 ± 1.16) (P < 0.05). CONCLUSIONS: This study highlights the importance of the SS position in surgery, with special reference to otologic, neurotologic, and posterior cranial fossa surgery. To avoid intraoperative complications, each patient should be evaluated preoperatively by appropriate radiologic methods.

Evaluation of the Radiological Anatomy of the Temporal Bone Air Spaces and Morphometric Analysis in Turkish Healthy Adults / Evaluación de la Anatomía Radiológica de los Espacios Aéreos del Hueso Temporal y Análisis Morfométrico en Adultos Turcos Sanos

SUMMARY: The temporal bone is a complicate structure which located on the lateral skull. The objective of the present study was to determine the temporal bone air spaces' morphometry, morphology, and pneumatization in Turkish healthy adult people. This retrospective observational study was carried out from 82 subjects (47 males, 35 females) aged 18-69 years. The external auditory canal and related structures' diameters and the volume of these areas were evaluated. The means and standard deviations of the Meatus acusticus externus length (MAEL), meatus acusticus externus pars cartilaginea length (MAEcL), meatus acusticus externus pars ossea length (MAEoL), meatus acusticus externus pars cartilaginea surface (MAEcS), meatus acusticus externus pars ossea surface (MAEoS), meatus acusticus externus volume (MAEV), meatus acusticus externus pars cartilaginea volume (MAEcV), meatus acusticus externus pars ossea volume (MAEoV), processus mastoideus air cells volume (PMACV), cavum tympani volume (CTV), and temporale pneumatic spaces volume (OTPSV) were found as 23.21±3.70 mm, 12.69±3.72 mm, 7.80±3.70 mm, 669.89±107.7 mm2, 267.50±30.51 mm2, 743.50±119.6 mm3, 971.97±156.69 mm3, 419.51±48.67 mm3, 5915.93±650.34 mm3, 673.48±91.93 mm3, 7813.34±717.49 mm3 have found in 82 subjects, respectively. In this paper, the morphometric and volume properties of the temporal bone cavities measurements were significantly higher in males than females. These results may both provide reference values of Turkish healthy population, and lead to decrease potential surgical complications about temporal and mastoid regions.

El hueso temporal es una compleja estructura ubicada en el parte lateral del cráneo. El objetivo del presente estudio fue determinar la morfometría, morfología y neumatización de los espacios aéreos del hueso temporal en individuos adultos turcos sanos. Este estudio observacional retrospectivo que se llevó a cabo en 82 sujetos (47 hombres, 35 mujeres) de entre 18 y 69 años. Se evaluaron los diámetros del meato acústico externo y las estructuras relacionadas y el volumen de estas áreas. Las medias y las desviaciones estándar de la longitud del meato acústico externo (MAEL), la longitud de la parte cartilaginosa del meato acústico externo (MAEcL), la longitud de la parte ósea del meato acústico externo (MAEoL), la superficie de la parte cartilaginosa del meato acústico externo (MAEcS), la superficie de la parte ósea del meato acústico externo (MAEoS), volumen del meato acústico externo (MAEV), volumen de la parte cartilaginosa del meato acústico externo (MAEcV), volumen de la parte ósea del meato acústico externo (MAEoV), volumen de las células aéreas del proceso mastoideo (PMACV), volumen del cavum tympani (CTV) y el volumen de los espacios neumáticos temporales (OTPSV) se encontró como 23,21 ± 3,70 mm, 12,69 ± 3,72 mm, 7,80 ± 3,70 mm, 669,89 ± 107,7 mm2, 267,50 ± 30,51 mm2, 743,50 ± 119,6 mm3, 971,97 ± 156,69 mm3, 419,5. 1±48,67 mm3, 5915,93 ± 650,34 mm3, 673,48 ± 91,93 mm3, 7813,34 ± 717,49 mm3, respectivamente. En este artículo, las propiedades morfométricas y de volumen de las mediciones de las cavidades del hueso temporal fueron significativamente mayores en hombres que en mujeres. Estos resultados pueden proporcionar valores de referencia de la población sana turca y conducir a una disminución de las posibles complicaciones quirúrgicas en las regiones temporal y mastoidea.

Imaging of Pathologies of the Temporal Bone and Middle Ear: Inflammatory Diseases, Their Mimics and Potential Complications-Pictorial Review.

Imaging of the temporal bone and middle ear is challenging for radiologists due to the abundance of distinct anatomical structures and the plethora of possible pathologies. The basis for a precise diagnosis is knowledge of the underlying anatomy as well as the clinical presentation and the individual patient's otological status. In this article, we aimed to summarize the most common inflammatory lesions of the temporal bone and middle ear, describe their specific imaging characteristics, and highlight their differential diagnoses. First, we introduce anatomical and imaging fundamentals. Additionally, a point-to-point comparison of the radiological and histological features of the wide spectrum of inflammatory diseases of the temporal bone and middle ear in context with a review of the current literature and current trends is given.

Risk factors for occurrence and progression of external auditory canal cholesteatoma.

OBJECTIVE: External auditory canal cholesteatoma (EACC) is characterized by retained squamous debris within the external canal and variable amounts of localized bone destruction. The etiology of primary EACC remains incompletely understood. This study was conducted to analyze the clinical features and backgrounds of patients with primary EACC and to clarify the risk factors for the occurrence and progression of EACC. METHODS: Sixty-nine ears of 62 patients diagnosed with primary EACC were included in this study (EACC group). Additionally, 74 ears of 60 patients with chronic otitis media (COM) with perforation who underwent tympanoplasty or myringoplasty were included as controls (COM group). We retrospectively investigated the clinical features, life history, and medical history of the patients in both groups. In addition, to investigate the risk factors for progression of EACC, we compared the clinical features and medical history of patients with stage IV (advanced) disease versus stage I + II (mild) disease. RESULTS: The inferior wall of the bony canal was the main structure affected in patients with primary EACC of all stages. The following factors were significantly more common in the EACC than COM group: older age, female sex, left-sided disease, osteoporosis, renal dysfunction, anemia, and treatment with bisphosphonates. Among these, the most significant factor associated with EACC was renal dysfunction (odds ratio, 11.4; 95 % confidence interval, 2.32-55.9). The significant factors observed in patients with stage IV disease were younger age, male sex, posterior wall involvement, and otorrhea. Surgical treatment was required for more than half of the patients with stage III and IV EACC. CONCLUSION: Patients with renal dysfunction are at risk of primary EACC. In particular, younger patients and relatively younger elderly patients with posterior wall involvement have a risk of progression to advanced-stage EACC. Canalplasty should be considered in patients with EACC who have these risk factors to prevent progression to advanced-stage disease.