Exclusive Transcervical Drainage for Posterior Mediastinal Abscess Originating from a Mandibular Molar.

The progression of a cervical abscess toward the mediastinum is rare but remains one of the most serious diseases, even in the era of antibiotics. A mediastinal abscess can originate from an odontogenic infection and presents a challenge for otolaryngologists and craniofacial surgeons, particularly when it spreads caudally to the tracheal bifurcation. For successful treatment of such an abscess, patients are generally referred to a thoracic surgeon for drainage. We present a distinctive case of an odontogenic infection-induced wide mediastinal abscess that could be drained only through cervical manipulation by using a sump-type tube. The patient was discharged on postoperative day 55 without any complications. This is the first report showing that descending mediastinal abscesses extending below the tracheal bifurcation could be drained by head and neck surgeons alone. The technique is easy and hence reproducible, safe, and convenient to perform.

Time Analysis of Recidivism in Acquired Cholesteatoma Using the Kaplan-Meier Method.

OBJECTIVE: To analyze the time trends of recidivism of acquired cholesteatoma using the Kaplan-Meier method. STUDY DESIGN: We conducted a retrospective, observational study of 256 patients having their first cholesteatoma surgery. The cumulative recidivism-free rate was calculated using Kaplan-Meier survival analysis related to the follow-up period, pathophysiology, the extent of the disease, and recidivism pathologies. RESULTS: Pars flacida cholesteatoma with tympanic cavity progression had a high likelihood of recurrence disease. Pars tensa cholesteatoma led to more recurrence of the disease than the residual disease. In both pars flacida and pars tensa cholesteatoma, the incidence of disease recurrence increased even 3 years after surgery. On the contrary, the incidence of residual disease peaked within 3 years after surgery, and thereafter, the incidence of residual disease tended to be small. In particular, pars flacida cholesteatoma extending into the mastoid cavity or tympanic cavity tended to recur up to 5 years postoperatively. CONCLUSIONS: We calculated the cumulative recidivism-free rates of 256 patients with cholesteatoma using Kaplan-Meier survival analysis. These results can lead to better estimates of the length of the follow-up period. LEVEL OF EVIDENCE: Level IV evidence from case-control studies.

Penetrating Trauma-Induced Perilymphatic Fistula: A Case Report and Literature Review.

This article highlights the importance of early identification and surgical treatment for extremely rare traumatic perilymphatic fistula (TPF) caused by an earpick, which can pose the risk of irreversible hearing loss. Herein, we have described two cases of TPF and reviewed the literature primarily based on surgical treatment for penetrating ear trauma-induced TPF.  We highlight the case of two females who sustained an accidental penetrating injury in the ear caused by the introduction of an earpick, leading to hearing loss and dizziness. Pure tone audiometry detected elevation of the bone-conduction thresholds. Computed tomography of Labyrinth revealed pneumolabyrinth in one case. Both patients underwent exploratory surgery, we completely repositioned the stapes that had invaginated into the vestibule in one case, in the other case, we reconnected the disarticulated incudostapedial joint and sealed perilymph fistula caused by rupture of the oval window. Both patients achieved hearing improvement and complete relief from the vestibular symptoms. The literature review indicated that a scar on the posterior aspect of the tympanic membrane was found in 44.4% of cases. Hearing improvement was observed in 45.5% and 25.0% of cases with invagination of stapes and fractured footplates by fistula repair, respectively. In terms of handling stapes dislocation, the hearing improvement rate was better in cases of complete stapes repositioning (66.7%) than those of complete or partial stapes removal (16.7%). Preoperative mild bone-conduction hearing loss or localized pneumolabyrinth are favorable factors for satisfactory hearing. When surgery is performed within 11 days of the injury, satisfactory hearing improvement can be expected.

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

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

Radiological and audiological prediction for hearing outcome in cholesteatoma recidivism surgery.

PURPOSE: In cholesteatoma recidivism, achieving satisfactory hearing outcome after revision surgery remains challenging. The presence of concomitant recidivism pathology or related anatomical abnormalities can impact revision reconstruction of the sound transmission system. The current study aimed to identify prognostic factors affecting hearing outcomes after surgery for cholesteatoma recidivism. METHODS: This retrospective cohort study included consecutive patients whose ears required initial surgery for recidivism between January 2016 and December 2021. Patients followed up for < 6 months and those not indicated for ossiculoplasty were excluded. The impact of preoperative otoscopic findings, computed tomography (CT) features, and hearing levels on the prediction of satisfactory hearing (postoperative air-bone gap [ABG] ≤ 20 dB) was evaluated using univariate and multivariate logistic regression analyses. RESULTS: Overall, 102 patients were included, with a mean follow-up of 24.8 months. Multivariate logistic regression analysis revealed the following independent predictive factors for satisfactory hearing: presence of aeration in the tympanic cavity (odds ratio [OR] [95% confidence interval {CI}]: 13.287 [1.113-158.604], p = 0.0409), absence of soft-tissue density occupying the oval window (OR [95% CI]: 13.445 [3.178-56.887], p = 0.0040), and ≤ 22.5 dB preoperative ABG in four-frequency average (OR [95% CI]: 9.339 [2.026-43.050], p = 0.0042). CONCLUSIONS: For cholesteatoma recidivism, reliable preoperative prediction based on CT and ABG would facilitate decision-making regarding the probability of efficient revision ossiculoplasty or appropriate preoperative counseling, including early hearing rehabilitation using hearing aids or implementation of simultaneous implantable hearing equipment during surgery for recidivism.

Imaging analysis of dural exposure in cholesteatomas with a skull base defect.

PURPOSE: Dural exposure during cholesteatoma surgery can pose a risk of cerebrospinal fluid leakage or residual disease. Therefore, delicate handling of the area surrounding the bone defect in the cranial fossa is required. However, in small-sized defects, preoperative prediction of dural exposure can be challenging. This study aimed to evaluate the diagnostic value of computed tomography (CT) for preoperative prediction of cholesteatoma-related dural exposure in bone discontinuities in the skull base. METHODS: We evaluated serial high-resolution CT images showing bone density discontinuities in the middle cranial fossa (MCF) requiring mastoidectomy for cholesteatoma. The CT and intraoperative findings were analyzed retrospectively. We evaluated the length between the superior margins of the bone density discontinuities using coronal CT planes. Receiver operating characteristic (ROC) curves were constructed to determine the optimal cut-off values. RESULTS: We extracted data from 107 bone density discontinuities, among which 54 (50.5%) showed dural exposure intraoperatively. Discontinuities with dural exposure (n = 54) had significantly greater lengths than did those without (n = 53) (p < 0.001, Wilcoxon rank-sum test). The area under the curve was 0.9780 according to the ROC analysis, and the optimal cut-off value was determined to be 2.99 mm (sensitivity 92.59%; specificity 94.34%). CONCLUSION: A bone density discontinuity length of > 2.99 mm in the MCF on coronal CT plane is a reliable diagnostic marker for cholesteatoma-related dural exposure. Thus, preoperative high-resolution CT analysis can inform optimal surgical preparation and planning before manipulating the area surrounding the osteolytic lesion in the MCF.

Endoscopic tympanoplasty type I using interlay technique.

BACKGROUND: Tympanoplasty using the interlay technique has rarely been reported in transcanal endoscopic ear surgery, unlike the underlay technique. This is because many surgeons find it challenging to detach the epithelial layer of the tympanic membrane using only one hand. However, the epithelial layer can be easily detached from the inferior part of the tympanic membrane. Another key point is to actively improve anteroinferior visibility even if the overhang is slight because most perforations and postoperative reperforations are found in the anteroinferior quadrant of the tympanic membrane. We report the application of the interlay technique in endoscopic tympanoplasty type I for tympanic perforations. METHODS: We retrospectively reviewed the medical records of 51 patients who had undergone tympanoplasty using the interlay technique without ossiculoplasty between 2017 and 2020. We then compared the data with those of patients who underwent microscopic surgery (MS) using the underlay technique between 1998 and 2009 (n = 104). No other technique was used in each group during this period. Repair of tympanic membrane perforation and hearing outcomes were assessed for > 1 year postoperatively. RESULTS: The perforation sites were limited to the anterior, posterior, and anterior-posterior quadrants in 23, 1, and 27 ears, respectively. Perforations were closed in 50 of the 51 ears (98.0%), and the postoperative hearing was good (average air-bone [A-B] gap was 6.8 ± 5.8 dB). The surgical success rate for the repair of tympanic membrane perforation was not significantly different from the MS group (93.3%, P = 0.15). The average postoperative average A-B gap in the group that underwent the interlay technique was significantly different from that in the MS group (10.1 ± 6.6 dB, P < 0.01). CONCLUSION: The interlay technique should be considered as one of the treatment methods in endoscopic surgery for tympanic perforations. Further study of the postoperative outcomes of this procedure should be conducted to establish the optimal surgical procedure for tympanic perforations. TRIAL REGISTRATION: This study was retrospectively approved by the Institutional Review Board of the Jikei University, Tokyo, Japan (approval number: 32-205 10286). Video abstract.

Preoperative prediction by artificial intelligence for mastoid extension in pars flaccida cholesteatoma using temporal bone high-resolution computed tomography: A retrospective study.

Cholesteatoma is a progressive middle ear disease that can only be treated surgically but with a high recurrence rate. Depending on the extent of the disease, a surgical approach, such as microsurgery with a retroarticular incision or transcanal endoscopic surgery, is performed. However, the current examination cannot sufficiently predict the progression before surgery, and changes in approach may be made during the surgery. Large amounts of data are typically required to train deep neural network models; however, the prevalence of cholesteatomas is low (1-in-25, 000). Developing analysis methods that improve the accuracy with such a small number of samples is an important issue for medical artificial intelligence (AI) research. This paper presents an AI-based system to automatically detect mastoid extensions using CT. This retrospective study included 164 patients (80 with mastoid extension and 84 without mastoid extension) who underwent surgery. This study adopted a relatively lightweight neural network model called MobileNetV2 to learn and predict the CT images of 164 patients. The training was performed with eight divided groups for cross-validation and was performed 24 times with each of the eight groups to verify accuracy fluctuations caused by randomly augmented learning. An evaluation was performed by each of the 24 single-trained models, and 24 sets of ensemble predictions with 23 models for 100% original size images and 400% zoomed images. Fifteen otolaryngologists diagnosed the images and compared the results. The average accuracy of predicting 400% zoomed images using ensemble prediction model was 81.14% (sensitivity = 84.95%, specificity = 77.33%). The average accuracy of the otolaryngologists was 73.41% (sensitivity, 83.17%; specificity, 64.13%), which was not affected by their clinical experiences. Noteworthily, despite the small number of cases, we were able to create a highly accurate AI. These findings represent an important first step in the automatic diagnosis of the cholesteatoma extension.

Combined analysis of finite element model and audiometry provides insights into the pathogenesis of conductive hearing loss.

The middle ear transmits sound to the inner ear via vibrations in the eardrum and ossicles, and damage to the middle ear results in conductive hearing loss. Although conductive hearing loss can be corrected by surgery, the currently available clinical investigations cannot always diagnose the ossicular chain pathology underlying the conductive hearing loss, and even intraoperative findings can be equivocal. Acoustic analysis using finite element models (FEMs) can simulate the sound pressure change at an arbitrary site for each frequency. FEMs are used in acoustic engineering to simulate the frequency-dependent sound pressure distribution at discrete cells in a simulated model and analyze the effects of specific parameters on the audiogram. However, few reports have compared the numerical results obtained using FEMs with data from clinical cases. We used FEMs to simulate audiograms of the air-bone gap (ABG) for various ossicular chain defects and compared these with preoperative audiograms obtained from 44 patients with a normal tympanic membrane who had otosclerosis, middle ear malformations or traumatic ossicular disruption. The simulated audiograms for otosclerosis and attic fixation of the malleus-incus complex both exhibited an up-slope but could be distinguished from each other based on the ABG at 1000 Hz. The simulated audiogram for incudostapedial joint discontinuity exhibited a peak at around 750 Hz and a down-slope above 1000 Hz. In general, the simulated audiograms for otosclerosis, attic fixation and incudostapedial joint discontinuity were consistent with those obtained from clinical cases. Additional simulations indicated that changes in ossicular mass had relatively small effects on ABG. Furthermore, analyses of combination pathologies suggested that the effects of one defect on ABG were added to those of the other defect. These FEM-based findings provide insights into the pathogenesis of conductive hearing loss due to otosclerosis, middle ear malformations and traumatic injury.

The pre-chorda and post-chorda tympani approach in endoscopic stapes surgery based on the chorda tympani nerve classification.

PURPOSE: In most stapes surgeries, the posterior ear canal is enlarged and a piston is inserted posterior to the chorda tympani nerve (post-chorda tympani approach; Post C). Although reports vary, some indicate that more than 60% of the patients experience lingual symptoms following surgery. Endoscopic surgery may permit an anterior approach to the nerve (pre-chorda tympani approach; Pre C). Herein, we propose a suitable approach for endoscopic stapes surgery based on the classification of the chorda tympani nerve. METHODS: We retrospectively reviewed the medical records of 23 patients who underwent endoscopic stapes surgery at our institution between 2019 and 2021. The nerve classification previously reported, the modified nerve classification (attached long type is divided into Category 1: lenticular process is visible with 0° endoscope and Category 2: not visible), selected approach (Pre C or Post C), use of a 30° endoscope, and manipulation of the nerve (number of contacts and traction, with or without suction, with or without malposition or extension and amputation, and damage score) were evaluated. RESULTS: The damage score was significantly lower in the Pre C group (p < 0.05); however, using this approach for all cases is not desirable owing to the high risk of damage to the nerve during posterior malpositioning. CONCLUSION: The Post C should be used for the detached and attached long 1 types, while the Pre C with a 30° endoscope should be used for the attached long 2, attached short, ultrashort, and external auditory canal types.

Impact of Sclerotic Lesions on the Surgical Outcome of Cholesteatoma.

OBJECTIVE: Cholesteatoma is occasionally accompanied by excessive calcification and presumably has different osteogenic dynamics compared to noncholesteatomous chronic otitis media. Cholesteatoma-related sclerotic lesions through the temporal bone can pose manipulatory difficulties, possibly leading to worse surgical outcomes or complications. Therefore, we compared surgical outcomes of cholesteatomas with and without sclerotic lesions. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic medical center. PATIENTS: Consecutive ears with acquired cholesteatomas requiring primary resection between January 2009 and December 2019. The ears followed up for <1 year were excluded. INTERVENTIONS: Tympanoplasty with/without mastoidectomy. MAIN OUTCOME MEASURES: Prevalence and location of sclerotic lesion, comorbid fistulae, postoperative air-bone gap, recidivism, and complications. RESULTS: Overall, 19 (6.4%) of 299 ears had sclerotic lesions. More than two-thirds (68.4%) of sclerotic lesions were located adjacent to the lateral semicircular canal (LSC). Among ears with sclerotic lesions adjacent to the LSC, 46.2% had a comorbid fistula in the LSC. The prevalence of labyrinth fistula was significantly greater in ears with sclerotic lesions (42.1%) than in ears without sclerotic lesions (5.0%) (p < 0.0001, Fisher's exact test). Sensorineural hearing deterioration was significantly higher in ears with sclerotic lesions than in ears without (p = 0.0004, Fisher's exact test). Multivariate logistic regression analysis demonstrated that the presence of sclerotic lesions was a significant prognostic factor for residual disease (odds ratio [95% confidence interval]: 6.820 [2.055-22.633], p = 0.0017). CONCLUSIONS: Surgeons should be conscious of preoperative identification of sclerotic lesions adjacent to one of the semicircular canals, possibly leading to postoperative sensorineural hearing deterioration or residual cholesteatoma.

Quantitative Study of Bone Removal Region in Transcanal Endoscopic Approach to the Attic and Antrum Using a 70° Endoscope.

BACKGROUND: Transcanal endoscopic ear surgery enables surgeons to operate with few blind areas, and using an angled endoscope expands its usefulness. We have previously reported the usefulness of a 70° endoscope in transcanal endoscopic ear surgery, but no quantitative study has been performed. We quantitatively clarified the difference between a microscope and various endoscopes in the bone removal region, especially a 70° endoscope, in the transcanal approach. METHODS: A temporal bone model for ear surgery training was used to compare the use of a microscope, a 0° endoscope, a 30° endoscope, a 45°endoscope, and a 70° endoscope. The drilled mass during atticotomy or atticoantrostomy and the size of the reconstructed graft were measured when the formed pseudo-lesion was removed. RESULTS: The amount of bone excision was 57% and the size of the reconstructed graft was 32% when using a 70° endoscope compared with the case of using a microscope, both of which were the smallest of the various endoscopes. CONCLUSION: It was quantitatively shown that using a 70° endoscope in transcanal endoscopic ear surgery reduced the bone removal region. We believe that a 70° endoscope is a useful tool for performing a minimally invasive and reliable surgery.

Retrograde mastoidectomy with canal wall reconstruction versus intact canal wall tympanomastoidectomy for cholesteatoma with minimal mastoid extension.

PURPOSE: Appropriate reconstruction of the canal wall or maintenance of the middle ear pressure in cholesteatoma may help in preventing recurrence. Retrograde mastoidectomy with canal wall reconstruction (RMR) can overcome the challenge of a wider canal wall defect or temporal bone immaturity, which possibly increases the recurrence risk. This study compared the outcomes of RMR and intact canal wall tympanomastoidectomy (ICW) for cholesteatomas with minimal mastoid extension and quantitatively evaluate the relationship between anatomical features and recurrence. METHODS: This single-center retrospective cohort study included patients who had undergone primary ICW or RMR for pars flaccida cholesteatoma with minimal mastoid extension from 2009 to 2019. The main outcome measures were anatomical measurements of the shortest distance between the cranial fossa and the upper canal wall (SCU), attic volume, and bony defect area of the canal wall (BDC) on computed tomography; recidivism; and postoperative air-bone gap (ABG). RESULTS: There were no significant differences in the preoperative anatomical factors, recidivism incidence, and postoperative ABG between the RMR (n = 20) and ICW (n = 60) groups. However, the median BDC was significantly greater in the RMR group (58.3 vs. 37.0 mm2). There was no significant difference in the SCU and attic volume between patients with and without recurrence. CONCLUSION: Selection of RMR or ICW may not affect recidivism and hearing outcomes in cholesteatoma with minimal mastoid extension. Bony defect size and attic narrowness were not associated with recurrence. Considering wider visualization and one-staged operation, RMR can be more adaptable than ICW for cholesteatoma with minimal mastoid extension.

Radiological and Audiological Prediction for Ossicular Fixation in Chronic Otitis Media and Tympanic Membrane Perforation.

OBJECTIVES: Recurrent middle-ear infection can lead to ossicular fixation, adversely affecting post-tympanoplasty hearing outcomes. Preoperative prediction of ossicular fixation remains challenging. We aimed to investigate potential predictors of ossicular fixation in patients with chronic otitis media. STUDY DESIGN: Retrospective. SETTING: Tertiary academic medical center. PATIENTS: Patients with noncholesteatomatous chronic otitis media and tympanic membrane perforation, without ossicular discontinuities. INTERVENTIONS: Diagnostic. MAIN OUTCOME MEASURES: The fixation of each ossicle was assessed during tympanoplasty. The impact of preoperative otoscopic findings, computed tomography (CT) features, and hearing levels on the prediction of ossicular fixation was evaluated using uni- and multivariable logistic regression analyses. RESULTS: One hundred thirty-five patients were included. Soft-tissue density between the malleus head and the anterior wall (odds ratio, 3.789 [95% confidence interval, 1.177-12.196]; p = 0.0255) and poor development of mastoid cells (16.826 [2.015-134.520]; p = 0.0078) were independent predictors of malleus fixation. In addition, ≥50% tympanic membrane perforation (5.412 [1.908-15.353]; p = 0.0015), poor development of mastoid cells (3.386 [1.039-11.034]; p = 0.0431), and a ≥40-dB preoperative air-bone gap (ABG) at 500 Hz (4.970 [1.732-14.261]; p = 0.0029) were independent predictors of incus fixation. Soft-tissue density surrounding the stapes (18.833 [1.856-191.104]; p = 0.0119) and a ≥40-dB preoperative ABG at 500 Hz (13.452 [1.640-∞]; p = 0.0138) were correlated with stapes fixation. CONCLUSIONS: The accurate prediction of ossicular fixation in patients with chronic otitis media based on CT features and the ABG may facilitate decision-making regarding the need for ossiculoplasty, possibly avoiding unnecessary manipulation or overlooking of fixation.

Prevalence of middle ear malformation and outcomes of tympanoplasty and/or canalplasty in patients with and without congenital external auditory canal stenosis.

OBJECTIVE: To compare the prevalence of middle ear malformations between patients with and without congenital external auditory canal stenosis (CEACS) and to investigate the outcomes of tympanoplasty and/or canalplasty in terms of tympanic membrane (TM) size and external auditory canal (EAC) stenosis in patients with middle ear malformation. METHODS: Twenty-five patients who underwent primary tympanoplasty and/or canalplasty for middle ear malformation at a tertiary academic medical center were retrospectively reviewed. CEACS was defined as an EAC diameter of 4 mm or less. Intraoperative findings, including irregularity of the ossicles, facial nerve, or chorda tympani; size of the TM and EAC on computed tomography; and pre- and postoperative hearing level, were collected. RESULTS: We included 7 and 18 patients with and without CEACS, respectively. The malleus handle defect, anterior deviation of the chorda tympani, and small TM (≤7 mm) (p-values 0.015, <0.001, and 0.003, respectively; Fisher's exact test) had significantly higher prevalence in patients with CEACS than in those without. The mean postoperative air-bone gap (ABG) in patients with CEACS was not significantly different from that in patients with normal-sized EAC (20.6 dB and 19.5 dB, respectively; p-value, 0.121; Mann-Whitney U test). No difference was observed in mean postoperative ABG between patients with small TM and those with normal-sized TM (19.2 dB and 20.0 dB, respectively; p-value, 0.469; Mann-Whitney U test). CONCLUSION: Patients with CEACS were more likely to have malleus handle defect, anterior deviation of the chorda tympani, and small TM than those without CEACS. Hearing outcome of patients with CEACS and a malformed malleus and/or incus might be equivalent to that of patients without CEACS following tympanoplasty and/or canalplasty, regardless of the EAC or TM size.

Non-echoplanar diffusion weighed imaging and T1-weighted imaging for cholesteatoma mastoid extension.

OBJECTIVES: A broad mastoid extension limits cholesteatoma resection via a transmeatal approach including endoscopic ear surgery. Therefore, a preoperative diagnosis of mastoid extension is a the most critical factor to determine whether to perform mastoidectomy. The purpose of this study was to assess the efficacy of non-echoplanar diffusion-weighted imaging (non-EPI DWI) and T1-weighted imaging in the evaluation of mastoid extension in cholesteatomas of the middle ear. METHODS: Patients who underwent magnetic resonance imaging (MRI) for pretreatment evaluation before primary surgery for pars flaccida or tensa cholesteatoma, which revealed a high-signal intensity in the mastoid on T2-weighed imaging were retrospectively evaluated. Two board-certified radiologists retrospectively evaluated the extent of cholesteatomas on MRI with non-EPI DWI, non-EPI DWI- and T1-weighted axial imaging. The presence of a high signal intensity on non-EPI DWI or low or high signal intensity on T1-weighted imaging in the mastoid was evaluated. All cases were subclassified as M+ (surgically mastoid extension-positive) or M- (surgically mastoid extension-negative). RESULTS: A total of 59 patients with middle ear cholesteatoma were evaluated. There were 37 M+ cases and 22 M- cases. High-signal intensity on non-EPI DWI exhibited a sensitivity of 0.89 and specificity of 0.82, whereas partial low-signal intensity on T1-weighted imaging exhibited a sensitivity of 0.84 and specificity of 0.91 for detecting mastoid involvement. Complete high-signal intensity on T1-weighted imaging exhibited a sensitivity of 0.73 and specificity of 0.89 for detecting non-involvement of the mastoid. The sensitivity (0.92) and specificity (0.96) of combined non-EPI DWI and T1-weighted imaging evaluation were higher than those of with non-EPI DWI or T1-weighted imaging alone. The interobserver agreement for the presence of high-signal intensity in the mastoid cavity on non-EPI DWI was very good at 0.82, that of a partial low-signal intensity area in the mastoid cavity lesions on T1-weighted imaging was good, at 0.76 and that of complete high-signal intensity in the mastoid cavity lesions on T1-weighted imaging was good, at 0.67. CONCLUSIONS: The signal intensity on non-EPI DWI and T1-weighted imaging of the mastoid could be used to accurately assess the extent of middle ear cholesteatoma, which could facilitate surgical treatment planning.

Imaging Analysis for Cholesteatoma Extension to the Perilymphatic Space in Labyrinth Fistulae.

OBJECTIVES/HYPOTHESIS: Disturbed perilymph behind a labyrinth fistula can lead to hearing deterioration; thus, delicate manipulation is required during surgery for cholesteatomatous fistulae with matrix extension to the perilymphatic space (EPS). However, it remains challenging to identify the EPS preoperatively. This study aimed to evaluate the diagnostic value of computed tomography (CT) for preoperative prediction of the EPS of cholesteatomatous fistulae. STUDY DESIGN: Retrospective study. METHODS: We included serial high-resolution CT images showing a cholesteatomatous bone defect in the lateral semicircular canal (LSC) requiring mastoidectomy. CT and intraoperative findings were analyzed retrospectively. Using axial CT planes, we evaluated the length and angle between the margins of bone defects. Receiver operating characteristic (ROC) curves were constructed to determine the cutoff points. RESULTS: We extracted data from 30 bone defects, of which six (20.0%) showed EPS intraoperatively. Bone defects with EPS (n = 6) had significantly greater length and angle values than those without EPS (n = 24) (P < .001 for both, Wilcoxon rank sum test). For length and angle, the area under the curve was 0.944 (95% confidence interval [CI]: 0.858-1.000) and 0.951 (95% CI: 0.875-1.000), respectively, according to the ROC analysis, and the optimal cutoff values were 3.65 mm and 71.6°, respectively, with 100% sensitivity and 91.67% specificity for both. CONCLUSIONS: Results demonstrated that a length >3.65 mm and an angle >71.6° for LSC bone defects on axial CT images are reliable diagnostic markers of EPS. Preoperative high-resolution CT analysis can provide surgeons with a more conscientious preparation for handling deeper labyrinth fistulae. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1301-E1307, 2021.

Preoperative predictive criteria for mastoid extension in pars flaccida cholesteatoma in assessments using temporal bone high-resolution computed tomography.

OBJECTIVES: We aimed to clarify the usefulness of high-resolution computed tomography (HRCT) and establish HRCT criteria for presurgical assessment of the mastoid extension in pars flaccida cholesteatomas of the middle ear. METHODS: Retrospective observational study. Patients who underwent primary surgery for pars flaccida cholesteatoma and those who underwent temporal bone HRCT for pretreatment evaluation were reviewed. The distance in the anterior-most portion of the mastoid sinus on HRCT was measured, and the presence of surgically verified mastoid extension of cholesteatoma was evaluated. All cases were subclassified as M+ (surgically mastoid extension-positive) or M- (surgically mastoid extension-negative). RESULTS: A total of 107 patients with pars flaccida cholesteatoma were included. The distance in the M+ cases was significantly longer than that in the M- cases, and the cutoff value was 3.6 mm. The difference between the ipsilateral/diseased-side distance and the contralateral/evaluable side (difference value) in M+ cases was larger than that in M- cases, with a cutoff value of 0.6 mm. The inter-rater reliability of this distance measurement was excellent, regardless of imaging experience. CONCLUSIONS: The cutoff values of the distance and the difference value can be used for pretreatment HRCT evaluation of mastoid extension in middle ear cholesteatoma with relatively high accuracy, regardless of the experience and skill levels of the evaluator.

The impact of middle ear aeration on surgical outcome after intact canal wall tympanoplasty for cholesteatoma.

OBJECTIVE: The aeration status of the middle ear is presumed to be one of the factors affecting the outcome in acquired cholesteatoma. The present study investigated the impact of postoperative middle ear aeration on hearing and recurrence after intact canal wall tympanoplasty. METHODS: We conducted a retrospective chart review of 127 pars flaccida cholesteatoma patients who underwent primary intact canal wall tympanoplasty at a tertiary academic medical center. We collected data on clinical characteristics, including extent of cholesteatoma, surgical procedure, pre- and postoperative middle ear aeration, hearing level, and recurrence. The aeration was measured before and at one year after operation on two axial computed tomography (CT) planes: at the lateral semicircular canal (mastoid cavity) and at the oval window (tympanic cavity). Based on the postoperative air-bone gap (ABG), patients were categorized into two groups: the successful hearing (ABG ≤15 dB) group and the unsuccessful hearing (ABG >15 dB) group. We used aeration ratio to assess the relationship between postoperative aeration improvement and hearing outcome or recurrence. Multivariate logistic regression analysis was used to identify the factors associated with hearing outcome. RESULTS: At one year after operation, aeration ratio in both mastoid and tympanic cavities was significantly improved than the preoperative status (p < 0.001, p < 0.001, respectively, Wilcoxon signed-rank test). The positive correlation was found between postoperative aeration ratios of mastoid cavity and tympanic cavity (r = 0.348, p < 0.001, Spearman's rank-correlation coefficient). In mastoid and tympanic cavities, the postoperative aeration ratio in successful hearing group (n = 57) was significantly higher than that in the unsuccessful hearing group (n = 45) at one year after operation (p < 0.001, p = 0.028, respectively, Mann-Whitney U test). Multivariate logistic regression analysis demonstrated that postoperative aeration ratio in mastoid cavity and preoperative ABG were significant independent prognostic factors for successful hearing (odds ratio [95% confidence interval]: 2.630 [0.985 - 7.024], p = 0.045; 0.891[0.840 - 0.944], p < 0.001, respectively). However, postoperative aeration ratios did not significantly differ between with (n = 14) and without recurrence (n = 113) groups in both cavities. CONCLUSION: Our results suggest that better postoperative aeration in mastoid cavity is independently associated with satisfactory hearing outcome after intact canal wall tympanoplasty in pars flaccida cholesteatoma. However, no significant differences were observed between middle ear aeration at one year after operation and recurrence.

The relationships among mastoid air cell development, tympanic sinus depth, and residual disease after surgery in children with congenital cholesteatoma.

Background: Mastoid development, tympanic sinus depth, and residual disease after surgery for congenital cholesteatoma are probably related, but these relationships have not been examined in detail.Aims/objectives: This study aimed to clarify the relationships between the abovementioned factors. Materials and Methods: The subjects were 31 patients with congenital cholesteatoma (stage III or IV in Potsic's staging system) that underwent mastoidectomy. The cross-sectional area of the mastoid air cells was measured as described previously. Tympanic sinus depth was classified into A-C using Marchioni et al.'s system.Results: Patients with deep tympanic sinuses or residual disease exhibited significantly greater mastoid air cell development. However, little residual disease was found in the mastoid air cells. Conversely, residual disease was observed more frequently in the patients with deep tympanic sinuses.Conclusions and significance: After surgery for congenital cholesteatoma, residual disease is more likely to occur in patients with marked mastoid growth, possibly because they have deep tympanic sinuses. Cases in which congenital cholesteatoma spreads to the mastoid air cells are classified as stage IV in Potsic's system, but our findings indicate that invasion into a deep tympanic sinus is more important than invasion into the mastoid air cells.