Congenital cholesteatoma assessment based on staging and classification criteria for middle ear cholesteatoma proposed by the Japan Otological Society.

OBJECTIVE: We aimed to assess the clinical characteristics of extent patterns in congenital cholesteatoma, based on the Japan Otological Society (JOS) staging system. METHODS: This was a retrospective chart review that included 80 ears of 80 patients with congenital cholesteatoma who underwent primary surgery at a tertiary academic medical center. The main characteristics and outcomes reviewed were sex, age, clinical background, surgical method, and stage classification according to two staging classifications: the criteria advocated by JOS and Potsic staging system. RESULTS: The age at the time of surgery ranged from 1 to 35 years (average 8.4 years), and there were 54 men and 26 women. According to the JOS staging system, 12 ears were Stage Ia (15%), 7 ears were Stage Ib (9%), 1 ear was Stage Ic (1%), 59 ears were Stage II (74%), and 1 ear was Stage III (1%). In the study of postoperative residual recurrence, there were 4 cases after the primary operation and 3 cases after the staged operation. All 3 ears with residual disease after planned surgery were cholesteatomas that extended to all the tympanomastoid space. CONCLUSION: We consider the JOS staging system to be more suitable, in terms of anatomical classification and surgical procedure selection for comparison between Europe, the United States, and Asia. Specifically, it was advantageous that the PTAM classification and the S classification are associated with surgical procedure selection and postoperative course.

Nationwide survey of middle ear cholesteatoma surgery cases in Japan: Results from the Japan Otological society registry using the JOS staging and classification system.

OBJECTIVE: This study was aimed to determine the characteristics of middle ear cholesteatoma and to investigate short-term outcomes regarding the rates of residual and recurrent cholesteatoma and the postoperative hearing results in Japan, via a nationwide survey using staging and classification criteria for middle ear cholesteatoma, as proposed by the Japan Otological Society (JOS). METHODS: The first-round survey was conducted in 2016. The target was patients with middle ear cholesteatoma who were surgically treated in Japan between January and December 2015. Medical information on the patients was anonymized. The questionnaire entries were age, sex, cholesteatoma classification and stage, preoperative hearing level, mastoid development, status of the stapes, and surgical method. There were a total of 1,787 registered patients from 74 facilities from all over Japan. The second survey was conducted in January 2018 and received 1,456 responses from 49 facilities in Japan. Of the 1,456 cases, 1,060 were conducted in the postoperative hearing survey and 1,084 in the residual recurrence survey. RESULTS: The most common cholesteatoma type was pars flaccida cholesteatoma (63.3%), followed by pars tensa cholesteatoma (13.0%), congenital cholesteatoma (12.9%), and cholesteatoma secondary to chronic tensa perforation (5.6%). Cholesteatoma of uncertain origin accounted for 5.0% (90 cases). Stage II was predominant in pars flaccida and pars tensa cholesteatoma, which frequently involves the mastoid, whereas about half of cases of cholesteatoma secondary to chronic tensa perforation and congenital cholesteatoma were classified as stage I. One hundred fifty-two of 1,084 cases (14.0%) had recurrent cholesteatoma, residual cholesteatoma, or both following first surgeries. The postoperative rates of hearing success rate was 63.3%. CONCLUSION: We were able to clarify not only the current epidemiological status of middle ear cholesteatoma but also the current trends of cholesteatoma surgery in Japan. The development of a staging system by the JOS Committee serving an epidemiological database for international or time-dependent comparison. It is possible to use this staging system with reasonable reliability.

Correlation between Surgical Outcome and Stage of Acquired Middle Ear Cholesteatoma: Revalidation of the EAONO/JOS Staging System.

OBJECTIVES: This study aimed to evaluate the intraoperative findings, recurrence rate, and hearing outcome of cholesteatoma surgery and correlate them with the newly proposed EAONO/JOS Joint Consensus Statement. MATERIALS AND METHODS: The records of 407 patients diagnosed with chronic otitis media and cholesteatoma between 2009 and 2017 were reviewed. After the exclusion of records with unsatisfactory surgical notes and anamnesis, 353 patients were included in the study. The 290 patients who had undergone primary surgery and 63 who had undergone revision surgery were evaluated separately. RESULTS: Total 162 of 290 (56%) patients had retraction pocket cholesteatoma and 128 of 290 (44%) patients had non-retraction pocket cholesteatoma. Eighty (28%) patients had stage I, 114 (39%) had stage II, 91 (31%) had stage III, and 5 (2%) had stage VI disease. The recurrence rate was 6.9% (20/290). The average age of these patients at the time of the second operation was 23.31±10.3 years. Twelve patients had (60%) recurrent cholesteatoma, and eight (40%) had residual cholesteatoma. Hearing outcome and surgical technique were significantly associated with the disease stage; however, the recurrence rate showed no such association. CONCLUSION: We concluded that the EAONO/JOS staging system is beneficial for estimating the postoperative hearing results and planning the surgical technique. However, there was no significant relationship between the recurrence rate and the EAONO/JOS staging system. We believe that additional factors, such as infection, ossicles, and invasion, predict the recurrence. Widespread use of the EAONO/JOS staging system will enable better evaluation of surgical outcomes and prognosis.

Clinical Characteristics of Patients with Cochlear Fistulas Caused by Chronic Otitis Media with Cholesteatoma.

OBJECTIVES: To analyze the clinical characteristics of cochlear fistulas (CFs) and propose a new fistula classification system with regard to the cochlea. MATERIALS AND METHODS: A retrospective chart review was conducted between January 2008 and December 2015 to identify patients who had undergone surgery for cholesteatoma with an associated CF. The following data were collected: preoperative symptoms, findings of temporal bone computed tomography (TBCT), fistula stage, cholesteatoma classification, surgical technique, and pre- and postoperative pure-tone audiometry. RESULTS: We analyzed a total of 159 patients, out of which 9 (5.7%) were diagnosed with a CF. The average duration of the chronic otitis media was 19.8 years. Cholesteatomas that induced CF rarely existed in the nonaggressive state; recurrent otorrhea was observed in all but one of our subjects. All the patients with CF had a distinct origin of cholesteatoma that developed from the retraction of posterior pars tensa; further, 88.9% cholesteatomas extended to and filled the sinus tympani. Preoperative audiometry revealed total hearing loss in 4 (44.4%) patients. Further, five patients with residual hearing before surgery had stage I fistulas, and the bone conduction thresholds remained stable after surgery. CONCLUSION: Cochlear fistulas were often detected in patients with (1) a history of chronic otitis media (exceeding 10 years), (2) frequently recurring otorrhea, and (3) pars tensa cholesteatomas that extended to the posterior mesotympanum and filled the sinus tympani. Such patients can suffer from potentially severe and irreparable sensorineural hearing loss.

Attic retraction pockets: Classification system.

INTRODUCTION: Although attic retractions have previously been classified into Grades 0 through IV, it is often not possible to assign attic retraction pockets into a single specific category. The present study describes an improved classification system based on otoscopic and endoscopic visualization of the retraction pocket fundus, the ossicular status in the attic, degree of scutal erosion, and the presence or absence of cholesteatoma. MATERIALS AND METHODS: One hundred and fifty-four patients (200 ears) with different grades of attic retraction pockets who were seen by a tertiary referral otology center between August 2015 and July 2018 were selected for this study. OBSERVATIONS: The new classification system (Grades I, IIa, IIb, IIIa, IIIb, IIIc, IVa, IVb, IVc, and V) was applied to these retraction pockets. Pure tone audiometry was obtained. RESULTS: All attic retraction pockets could be classified precisely using the new classification system. Forty-four of 200 (22%) of ears showed Grade I Attic retraction, 18 ears showed Grade IIa (9%), 14 showed Grade IIb (7%), 28 showed Grade IIIa (14%), 12 showed IIIb (6%), 20 showed Grade IIIc (10%), 16 showed grade IVa (8%), 12 showed grade IVb (6%), 28 showed grade IVc (14%), and eight showed grade V (4%) attic retraction pockets. Grades I, IIa, IIb, IIIa, and IVa had no significant hearing loss. Average hearing loss was 42 dB and 52 dB in Grades IIIb and IIIc, 44 dB and 58 dB in Grades IVb and IVc, and 61 dB in Grade V. LEVEL OF EVIDENCE: 5 Laryngoscope, 130: 2034-2039, 2020.

Clinical Characteristics of Pars Tensa Cholesteatoma: A Comparative Study of Area-Based Classification Systems Proposed by the Japanese Otological Society and the European Academy of Otology - Neuro-Otology.

OBJECTIVES: To assess the clinical characteristics of extent patterns in pars tensa cholesteatoma. MATERIALS AND METHODS: This was a retrospective chart review. Forty-four patients with pars tensa cholesteatoma who underwent primary surgery at a tertiary academic medical center were included. The main outcomes measured were sex, age, clinical background, and stage classification of pars tensa cholesteatoma (including the extent of cholesteatoma and involvement of the sinus tympani) according to two staging classifications: criteria advocated by the Japanese Otological Society (JOS) and those advocated by the European Academy of Otology and Neuro-Otology (EAONO)/JOS joint consensus statements. RESULTS: The mean patient age ± standard deviation was 38.4±19.6 years. The patients comprised 19 men and 25 women. According to the JOS classification, 18 ears (40.9%) were classified as stage I, 22 (50.0%) as stage II, and 4 (9.1%) as stage III. According to the EAONO/JOS joint consensus statements, 14 ears (31.8%) were classified as stage I, 26 (59.1%) as stage II, and 4 (9.1%) as stage III. Fourteen ears (31.8%) demonstrated involvement of the sinus tympani. Four ears (9.1%) that were originally categorized as stage I cholesteatoma by the JOS criteria showed sinus tympani invasion and were subsequently categorized as stage II according to the EAONO/JOS criteria. CONCLUSION: We determined the clinical characteristics of pars tensa cholesteatoma based on the novel and well-defined classification criteria. Further studies including long-term outcomes are necessary to demonstrate the clinical relevance of the discrepancy between the two criteria with respect to involvement of the sinus tympani.

Short-Term Hearing Prognosis of Ossiculoplasty in Pars Flaccida Cholesteatoma Using the EAONO/JOS Staging System.

OBJECTIVES: The aim of the present study was to investigate the prognostic factors for short-term hearing outcomes of ossiculoplasty for primary pars flaccida cholesteatoma according to the European Academy of Otology and Neurotology/Japanese Otological Society (EAONO/JOS) and 2015 JOS staging systems. MATERIALS AND METHODS: A total of 34 patients with primary pars flaccida cholesteatoma who underwent one-stage tympanomastoidectomy with partial ossicular reconstruction using double cartilage block were included in the study. The postoperative pure-tone average air-bone gap (PTA-ABG) was calculated, and two criteria of successful hearing outcomes were defined as ≤10 and ≤20 dB. Patients were classified according to the EAONO/JOS and 2015 JOS staging systems. Cochran-Armitage test was used to statistically analyze staging, and Fisher's exact test was used to analyze other factors. RESULTS: Successful hearing outcome with postoperative PTA-ABG ≤10 and ≤20 dB occurred in 23.5% and 55.9% of cases, respectively. When postoperative PTA-ABG ≤20 dB was defined as successful, the success rate significantly decreased with increase in EAONO/JOS stage, and S0 pathological status of the stapes (no involvement) was a significantly favorable predictive factor. When postoperative PTA-ABG ≤10 dB was regarded as successful, the significantly favorable predictive factors were S0 pathological status of the stapes and development of mastoid cells with MC2-3 (better developed cells). CONCLUSION: Favorable prognostic factors for hearing outcomes of tympanomastoidectomy with partial ossicular reconstruction for primary pars flaccida cholesteatoma were low stage following the EAONO/JOS staging system and no stapes involvement and better development of mastoid cells following the 2015 JOS staging system.

International Collaborative Assessment of the Validity of the EAONO-JOS Cholesteatoma Staging System.

OBJECTIVE: Assessment of validity of the Japanese Otological Society and the European Academy of Otology and Neurotology (EAONO-JOS) cholesteatoma staging system (EJS) through international collaboration to investigate: (a) feasibility of retrospectively staging previously acquired data, (b) strengths and weaknesses of the staging system. METHOD: Nine centers with prospective cholesteatoma databases were recruited. Cases were allocated to EJS Stage at each center using details from time of initial surgery. An independent rater also staged the cases and noted any discrepancies. At one center results from database staging were compared with staging based on contemporaneous operative records. Inter and intrarater reliabilities were calculated, and recidivism rates calculated according to Stage. RESULTS: Of 1482 cases of cholesteatoma, 320 (22%) were Stage 1, 977 (67%) Stage 2, 153 (11%) Stage 3 and 4 (0.3%) Stage 4. No database contained details of all parameters required for accurate staging. Staging discrepancies occurred in >10% cases but inter and intrarater reliability of staging were high (Kappa 0.8; 95% confidence interval between 0.7-0.9). At 5 years, 11% had residual and 8% had recurrent cholesteatoma: rates increased with Stage but generally not significantly (Kaplan-Meier Log Rank analysis). CONCLUSION: The EJS Staging system provides an internationally agreed standard for collecting data to classify cholesteatoma severity. Although data can be applied retrospectively with reasonable reliability, prospective data collection would prevent inaccuracies that arise from missing data fields. To enhance validity of the EJS system, we propose clearer definitions of some categories. Refinements to definitions of stage may improve prognostic utility of the EJS but should be made using evidence powered by large-scale collaboration.

Multidetector Computed Tomography Findings of Auto-Evacuated Secondary Acquired Cholesteatoma: A Morphologic and Quantitative Analysis.

OBJECTIVES: To describe and quantify computed tomography (CT) findings of auto-evacuated (spontaneously drained) secondary acquired cholesteatoma (SAC). MATERIALS AND METHODS: This multicenter retrospective study included 69 patients with intermittent ear discharge diagnosed with SAC by autoscopy or automicroscopy who were surgically treated. Three independent radiologists measured the medial and lateral attic distance on coronal and axial planes using multidetector computed tomography (MDCT) in 75 ear CTs from 69 patients with intraoperatively verified diagnoses of pars flaccida cholesteatoma (n=36), pars tensa cholesteatoma (n=24), and auto-atticotomy or automastoidectomy (n=15) and compared them with contralateral healthy ears. RESULTS: A circular or elliptical air-filled cavity surrounded by granulation tissue was morphologically detected on MDCT in these patients. The lateral attic distance was significantly higher in pars flaccida cholesteatoma cases than in contralateral healthy ears on both coronal and axial planes (p<0.05). The medial attic distance was significantly higher in pars tensa cholesteatoma cases than in contralateral healthy ears in the axial pane, but with no difference in the coronal plane. CONCLUSION: In patients with chronic intermittent aural discharge, nonopacified areas surrounded by granulation tissue, which expands the medial or lateral attic in a CT scan, suggest an auto-evacuated cholesteatoma.

Practical analysis of pars flaccida cholesteatoma with classification and staging system proposed by Japan Otological Society: a comparative study.

BACKGROUND: The Japan Otology Society (JOS) proposed the classification and staging system for middle ear cholesteatoma. However, there was little analysis of the pathology of cholesteatoma using this staging system. AIMS/OBJECTIVES: To analyze the pathology of pars flaccida cholesteatoma using the staging system by JOS. MATERIAL AND METHODS: A total of 183 cases of fresh pars flaccida cholesteatoma treated between January 2009 and December 2015 were included. We used the staging system recommended by JOS (2015). The association of the following variables in each stage of pars flaccida cholesteatoma was examined: age, gender, preoperative hearing level, staging, statuses of mastoid cell growth and stapes, tympanic sinus invasion. RESULTS: Stage II disease showed the highest degree of progression, and peak incidence was observed in the third and fourth decades of life. Stage III significantly increased after the age of 40 years. The progression of the disease stage was significantly associated with deterioration of hearing level. Cholesteatoma invasion to tympanic sinus was recognized in 14.2% of cases. The state of the stapes is increasingly likely be to fracture as stage progresses. CONCLUSIONS: The JOS Staging System appropriately reflects the disease state, and it was found to be clinically meaningful in this study.

Practicality analysis of the staging system proposed by the Japan Otological Society for acquired middle ear cholesteatoma: A multicenter study of 446 surgical cases in Japan.

OBJECTIVE: The Objective of this study was to assess the practicality of the cholesteatoma staging system proposed by the Japan Otological Society (JOS) for acquired middle ear cholesteatoma (the 2010 JOS staging system). METHODS: Between 2009 and 2010, 446 ears with retraction pocket cholesteatoma underwent primary surgery at 6 institutions in Japan. The extent of cholesteatoma was surgically confirmed, and classified into three stages. RESULTS: The cholesteatoma affected the pars flaccida in 325 ears (73%), the pars tensa in 100 ears (22%), and both regions combined in 21 ears (5%). The hearing outcome (postoperative air-bone gaps dB) worsened as follows (Stage I, II, III): 84%, 68%, 53% in pars flaccida; 71%, 62%, 30% in pars tensa, and 42% at Stage II, and 50% at Stage III in the combined group. The incidence of residual cholesteatoma increased as follows (Stage I, II, III): 2%, 12%, 23% in pars flaccida; 7%, 30%, 21% in the pars tensa group. The severity of disease was reflected in postoperative hearing and increasing incidence of recurrence rate. CONCLUSION: The 2010 JOS staging system is suitable for evaluating initial pathology. It is particularly practical for standardizing reporting of retraction pocket cholesteatoma and for adjusting for the severity of the condition during outcome evaluations. It may also provide information that is useful for counseling patients.

Cholesteatoma Definition and Classification: A Literature Review.

Cholesteatoma is a serious otolaryngologic condition that to date remains an important problem and poses a challenge to otolaryngologists around the world. To improve the approach pertaining to the diagnosis and management of middle ear cholesteatoma, clear, clinically applicable, and useful definition and classification of cholesteatoma are required. This review aimed to evaluate the current and most accepted descriptions and opinions concerning cholesteatoma. A review of the literature concerning different definitions and classifications of cholesteatoma was used in the preparation of the Cholesteatoma Guidelines, a project implemented by the European Academy of Otology - Neuro-otology.

EAONO/JOS Joint Consensus Statements on the Definitions, Classification and Staging of Middle Ear Cholesteatoma.

The European Academy of Otology and Neurotology (EAONO) has previously published a consensus document on the definitions and classification of cholesteatoma. It was based on the Delphi consensus methodology involving the broad EAONO membership. At the same time, the Japanese Otological Society (JOS) had been working independently on the "Classification and Staging of Cholesteatoma." EAONO and JOS then decided to collaborate and produce a joint consensus document. The EAONO/JOS joint consensus on "Definitions, Classification and Staging of Middle Ear Cholesteatoma" was formally presented at the 10th International Conference on Cholesteatoma and Ear Surgery in Edinburgh, June 5-8, 2016. The international otology community who attended the consensus session was given the chance to debate and give their support or disapproval. The statements on the "Definitions of Cholesteatoma" received 89% approval. The "Classification of Cholesteatoma" received almost universal approval (98%). The "EAONO/JOS Staging System on Middle Ear Cholesteatoma" had a majority of approval (75%). Some international otologists wanted to see more prognostic factors being incorporated in the staging system. In response to this, the EAONO/JOS steering group plans to set up an "International Otology Outcome Working Group" to work on a minimum common otology data set that the international otology community can use to evaluate their surgical outcome. This will generate a large database and help identify relevant prognostic factors that can be incorporated into the staging system in future revisions.

Staging and classification criteria for middle ear cholesteatoma proposed by the Japan Otological Society.

In order to provide a basis for meaningful exchange of information among those treating cholesteatoma, the Committee on Nomenclature of the Japan Otological Society (JOS) was appointed in 2004 to create a cholesteatoma staging system as simple as possible to use in clinical practice in Japan. Following the announcement of preliminary criteria for the staging of pars flaccida (attic) cholesteatoma in 2008, we proposed the 2010 JOS staging system for two major types of retraction pocket cholesteatoma, pars flaccida and pars tensa cholesteatoma. Since then, the JOS staging system has been widely used in clinical studies of cholesteatoma in Japan, allowing standardization in reporting of surgical outcomes based on the respective stages of cholesteatoma. We have recently expanded the range of cholesteatoma by adding cholesteatoma secondary to a tensa perforation and congenital cholesteatoma as the 2015 JOS staging system for middle ear cholesteatoma. Although further revisions may be required for universal acceptance of these criteria, we hope our staging system will open the way for international consensus on staging and classification of middle ear cholesteatoma in the near future.

[Analyses of the operative efficacy of 102 cases of acquired middle ear cholesteatoma].

OBJECTIVE: To investigate the efficacy of operations of acquired middle ear cholesteatoma. METHODS: Retrospectively analyzed clinical data of 102 patients whom received tympanoplasty with CWU or CWD with mastoid obliteration in our hospital between January 2014 and December 2014. Patients were divided into different groups according to types of the cholesteatoma as well as the different surgical procedures. Patients were followed up for 12-24 months, the pre and post-operative PTA was performed and evaluated. The post-operative hearing was assessed in terms of average ABG. RESULTS: The average dry ear time was (5.4±1.7)weeks. The dry ear time of patients of attic cholesteatoma was shorter than those of tensa cholesteatoma[(4.9±1.7)weeks vs(6.1±1.5)weeks, t=-3.52, P=0.001]; the dry ear time of patients underwent CWU was shorter than those underwent CWD with mastoid obliteration[(2.3±0.5)weeks vs(5.8±1.4)weeks, t=-8.43, P=0.000]. Mean pre and post-operative air bone gaps in 93 ears underwent ossiculoplasty were (34.2±11.8)dB and (19.0±5.5)dB respectively and these differences were statistically significant. Both the pre and post-operative air bone gaps of ears of attic cholesteatoma were smaller than those ears of tensa cholesteatoma(P<0.05). In the patients who underwent ossiculoplasty with CWD with mastoid obliteration, the post-operative air bone gaps of attic cholesteatoma were smaller than those of tensa cholesteatoma(P<0.05). Both the pre and post-operative air bone gaps of ears underwent CWU were smaller than those underwent CWD with mastoid obliteration(P<0.05). The post-operative air bone gaps of ears underwent PORP with CWD with mastoid obliteration were smaller than those underwent TORP with CWD with mastoid obliteration(P<0.05). CONCLUSIONS: Both the hearing loss and the outcome of tensa cholesteatoma are worser than attic cholesteatoma. The outcome of PORP is better than TORP. The patients who will accept CWU should be selected more carefully and be followed up regularly.

Classification of Cholesteatoma According to Growth Patterns.

IMPORTANCE: Several classifications of cholesteatoma exist, but there are controversies about their clinical application. OBJECTIVE: To classify cholesteatomas and describe the prevalence of the subtypes. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional comparative study of 414 ears in 356 consecutive patients with middle ear cholesteatoma and no history of ear surgery treated at a tertiary hospital was conducted from March 8, 2000, to March 30, 2015. Data analysis was conducted from March 30, 2014, to March 30, 2015. INTERVENTION: Otoendoscopy was conducted, and findings for both ears were recorded. MAIN OUTCOMES AND MEASURES: Cholesteatoma growth patterns were classified as anterior epitympanic, posterior epitympanic, posterior mesotympanic, 2 routes (both the pars flaccida and the pars tensa are involved), and undetermined. RESULTS: Among the 356 patients in this study, mean (SD) patient age was 33.23 (19.81) years (range, 4-82 years), and 125 patients (35.1%) were female. The right ear was identified as the affected ear in 220 patients (61.8%). A total of 272 (65.7%) ears were from adults. Of the 414 ears that underwent otoendoscopy, posterior epitympanic (142 [34.3%]) and posterior mesotympanic (140 [33.8%]) were the most frequent types of cholesteatoma observed, followed by undetermined (67 [16.2%]) and 2 routes (57 [13.8%]). Anterior epitympanic type was the least frequent (8 [1.9%]). Posterior epitympanic cholesteatoma was more prevalent in adults (111 [40.8%]), whereas posterior mesotympanic cholesteatoma was more frequent in children (43.0%) (P < .001). Anterior epitympanic cholesteatoma was observed only in children. CONCLUSIONS AND RELEVANCE: Classifying cholesteatomas according to the growth pattern (anterior epitympanic, posterior epitympanic, posterior mesotympanic, 2 routes, and undetermined) includes all existing types of cholesteatomas of the middle ear. In general, the prevalence of posterior epitympanic and posterior mesotympanic cholesteatoma were similar. Whereas anterior epitympanic and posterior mesotympanic cholesteatomas were more prevalent in children, posterior epitympanic cholesteatoma was more frequent in adults.

The difference in congenital cholesteatoma CT findings based on the type of mass.

OBJECTIVE: A retrospective assessment of differences in congenital cholesteatoma CT findings with a focus on type of cholesteatoma mass. MATERIALS AND METHODS: The medical records and CT images of 14 patients with congenital cholesteatomas in the middle ear who underwent surgery at our institution between January 2009 and July 2014 were reviewed. Cholesteatomas were classified as closed type, open type, or mixed type based on intraoperative findings. The CT findings including cholesteatoma size, location, and shape were retrospectively reviewed. RESULTS: Eight patients had closed type cholesteatomas, four had mixed type, and two had open type. The mean size of all cholesteatomas was 5.1mm. None of the cholesteatoma types indicated a tendency towards a certain location. The round shape was observed more frequently in closed type cholesteatomas than in other types (closed: 5/8; mixed: 1/4; open: 0/2). Two large closed type cholseteatomas and two mixed type cholesteatomas exhibited a constricted shape. Both of the open type cholesteatomas displayed an irregular shape. CONCLUSION: Small closed type congenital cholesteatomas were typically observed as round shaped lesions, but large closed type cholesteatomas and other type cholesteatomas tended to display shapes other than round.