The value of non-echo planar HASTE diffusion-weighted MR imaging in the detection, localisation and prediction of extent of postoperative cholesteatoma

MRI-DWI detection of residual cholesteatoma: moving toward an optimum follow-up scheme

PURPOSE

To analyse diagnostic accuracy of MRI-DWI in detecting residual disease after cholesteatoma surgery and propose an optimum follow-up (FU) scheme.

METHOD

A retrospective chart review of patients who had cholesteatoma surgery in a tertiary referral centre. 3.0 T non-echo planar diffusion weighted imaging was performed as part of routine FU or indicated on the basis of clinical suspicion of disease. Imaging outcome was verified per-operatively during a second-look procedure or ossicular chain reconstruction. Diagnostic parameters were calculated and stratified by FU length.

RESULTS

For the FU of 664 cholesteatoma surgeries, 1208 MRI-DWI were obtained and 235 second-look procedures were performed. Most MRI-DWI were obtained within 1.5 yrs of surgery. In this period, significantly less true positive MRI-DWI and significantly more false negative MRI-DWI for residual disease were found compared to other FU periods. Scanning after approximately 3 yrs yielded a significantly higher rate of true positive MRI-DWI, while sensitivity surpassed 80%. Younger patients had a higher risk of developing residual disease. Patients undergoing canal wall up surgery, as well as patients < 12 yrs, were at risk for false negative MRI-DWI. Obliteration reduces the risk of residual disease, while leading to less false negative MRI-DWI.

CONCLUSION

A novel radiologic FU scheme for detecting residual disease is suggested for stable ears after cholesteatoma surgery: standard MRI-DWI approximately 3 and 5 yrs after primary surgery, as well as MRI-DWI after approximately 9 yrs for patients with specific risk factors (i.e., patients < 12 yrs or patients undergoing canal wall up surgery without obliteration).

Early non-EPI DW-MRI after cholesteatoma surgery

OBJECTIVE

Middle ear cholesteatoma may lead to the erosion of the bony structures of the temporal bone, possibly causing intra- and extracranial complications. Surgical treatment is mandatory, and due to possible residual/recurrent disease, the use of reliable diagnostic methods is essential. Our study aimed to evaluate the reliability of non-EPI DW-MRI for the follow-up of cholesteatoma after surgery.

METHODS

In a study group including 53 consecutive patients who underwent surgery for cholesteatoma at a tertiary university hospital, an imaging protocol was applied, including non-echo planar diffusion-weighted imaging magnetic resonance (MR) at 1 month after surgery and then at 6 and 12 months after surgery. Based on the combination of preoperative assessment and intraoperative findings, the study group was divided into 3 subgroups: petrous bone (PB) cholesteatoma, complicated cholesteatoma and uncomplicated cholesteatoma. PB cholesteatoma patients were treated by a subtotal petrosectomy, whereas complicated and uncomplicated cholesteatoma patients were treated either by a canal wall up procedure or a retrograde (inside-out) canal wall down technique with bone obliteration technique (BOT).

RESULTS

The results show that patients who had positive findings on non-EPI DW-MRI scans 1 month after surgery consequently underwent revision surgery during which residual cholesteatoma was noted. All the patients who displayed negative findings on non-EPI DWI-MRI scan at 1 month after surgery did not show the presence of a lesion at the 6- and 12-month evaluations. The 6 patients who displayed residual cholesteatoma at the 1-month follow-up presented dehiscence/exposure of the facial nerve canal at the primary surgery, mostly at the level of the labyrinthine segment.

CONCLUSION

Non-EPI DW-MRI is a useful and reliable tool for follow-up cholesteatoma surgery, and when applied early, as was done in the protocol proposed in the present study, this tool may be used to detect the presence of residual cholesteatoma in some patients, prompting the planning of early revision surgery.

Cost-Effectiveness of Diffusion Weighted MRI Versus Planned Second-Look Surgery for Cholesteatoma

OBJECTIVE

To compare the cost-effectiveness of serial non-echo planar diffusion weighted MRI (non-EP DW MRI) versus planned second look surgery following initial canal wall up tympanomastoidectomy for the treatment of cholesteatoma.

METHODS

A decision-analytic model was developed. Model inputs including residual cholesteatoma rates, rates of non-EP DW MRI positivity after surgery, and health utility scores were abstracted from published literature. Cost data were derived from the 2022 Centers for Medicare and Medicaid Services fee rates. Efficacy was defined as increase in quality-adjusted life year (QALY). One- and 2-way sensitivity analyses were performed on variables of interest to probe the model. Total time horizon was 50 years with a willingness to pay (WTP) threshold set at $50 000/QALY.

RESULTS

Base case analysis revealed that planned second-look surgery ($11 537, 17.30 QALY) and imaging surveillance with non-EP DWMRI ($10 439, 17.26 QALY) were both cost effective options. Incremental cost effectiveness ratio was $27 298/QALY, which is below the WTP threhshold. One-way sensitivity analyses showed that non-EP DW MRI was more cost effective than planned second-look surgery if the rate of residual disease after surgery increased to 48.3% or if the rate of positive MRI was below 45.9%. A probabilistic sensitivity analysis at WTP of $50 000/QALY found that second-look surgery was more cost-effective in 56.7% of iterations.

CONCLUSION

Non-EP DW MRI surveillance is a cost-effect alternative to planned second-look surgery following primary canal wall up tympanomastoidectomy for cholesteatoma. Cholesteatoma surveillance decisions after initial canal wall up tympanomastoidectomy should be individualized.

LEVEL OF EVIDENCE

V.

The diagnostic utility of diffusion-weighted magnetic resonance imaging and high-resolution computed tomography for cholesteatoma: A meta-analysis

Objective

The purpose of this meta-analysis was to compare the efficiency of high-resolution computed tomography (HRCT) and diffusion-weighted magnetic resonance imaging (DWI) in guiding the diagnosis of middle ear cholesteatoma in clinical practice.

Materials and methods

Cochrane Library, Medline, Embase, PubMed, and Web of Science were searched for studies that evaluated the sensitivity and specificity of HRCT or DWI in detecting middle ear cholesteatoma. A random-effects model was used to calculate and summarize the pooled estimates of sensitivity, specificity, and diagnostic odds ratios. Postoperative pathological results were considered as the diagnostic gold standard for middle ear cholesteatoma.

Results

Fourteen published articles (860 patients) met the inclusion criteria. The sensitivity and specificity of DWI when diagnosing cholesteatoma (regardless of type) were 0.88 (95% confidence interval [CI], 0.80-0.93) and 0.93 (95% CI, 0.86-0.97), respectively, while those of HRCT were 0.68 (95% CI, 0.57-0.77) and 0.78 (95% CI, 0.60-0.90), respectively. Notably, the sensitivity and specificity levels of DWI were similar to those of HRCT (p = .1178 for sensitivity, p = .2144 for specificity; pair-sampled t tests). The sensitivity and specificity of DWI or HRCT for the diagnosis of primary cholesteatoma were 0.78 (95% CI, 0.65-0.88) and 0.84 (95% CI, 0.69-0.93), respectively, while that for recurrent cholesteatoma were 0.93 (95% CI, 0.61-0.99) and 0.94 (95% CI, 0.82-0.98), respectively.

Conclusion

DWI and HRCT have similar levels of high sensitivity and specificity in detecting various cholesteatomas. Also, the diagnostic efficiency of HRCT or DWI for recurrent cholesteatoma is identical to that of primary cholesteatoma. Therefore, HRCT may be used in clinical settings to reduce the use of DWI and save clinical resources.

Lay summary

Data on the use of diffusion-weighted magnetic resonance imaging and high-resolution computed tomography in the diagnosis of cholesteatoma were obtained through a literature search. They were analyzed to guide the clinical diagnosis and treatment of cholesteatoma.

Level of evidence

NA.

Localization Evaluation of Primary Middle Ear Cholesteatoma With Fusion of Turbo Spin-Echo Diffusion-Weighted Imaging and High-Resolution Computed Tomography

OBJECTIVE

The aim of the study is to evaluate the application of high-resolution computed tomography (HRCT) and turbo spin-echo diffusion-weighted imaging (TSE-DWI) fusion imaging for localization of middle ear cholesteatomas.

METHODS

Eighty-six patients with clinically suspected middle ear cholesteatomas were enrolled prospectively. Ear TSE-DWI and HRCT scans were performed using a postprocessing workstation to generate a TSE-DWI-CT fusion image. Subsequently, all the enrolled patients received surgical treatment. According to the STAM system (difficult access sites [S], the tympanic cavity [T], the attic [A], and the mastoid [M]), the agreement between the localization of lesions evaluated by HRCT, TSE-DWI, and TSE-DWI-CT fusion images and the intraoperatively recorded localization were computed using Cohen κ statistic.

RESULTS

Based on the pathological results, the enrolled patients were divided into a cholesteatoma (n = 50) and a noncholesteatoma group (n = 36). The area under the receiver operator characteristic curve for diagnosis of cholesteatoma with TSE-DWI-CT fusion imaging was identical to that using the TSE-DWI images (0.924 vs 0.924, P > 0.05), but was significantly higher than that with HRCT imaging (0.924 vs 0.767, P = 0.0005). Furthermore, the diagnostic sensitivity and specificity of TSE-DWI-CT fusion imaging for cholesteatomas were 96.0% and 88.9%, respectively. Depending on whether the cholesteatoma extended to the mastoid, TSE-DWI-CT fusion imaging demonstrated good agreement with the intraoperative record for localization of lesions (κ = 0.808) and had a high accuracy of localization by the STAM system.

CONCLUSIONS

Turbo spin-echo-DWI-CT fusion images have a very high diagnostic value for the preoperative localization of cholesteatomas.

Non-echo Planar Diffusion-Weighted Imaging in the Detection of Recurrent or Residual Cholesteatoma: A Systematic Review and Meta-Analysis of Diagnostic Studies

We performed a systematic review and meta-analysis of patients with suspected recurrent cholesteatoma who underwent non-echo planar imaging (non-EPI) using diffusion-weighted magnetic resonance imaging (MRI), with surgery as the reference standard. We searched Medline, Google Scholar, and the Cochrane database for diagnostic test accuracy studies. The following prespecified subgroup analyses were performed: patient age, number of radiologists interpreting MRI, study design, and risk of bias. We used a bivariate model using a generalized linear mixed model to pool accuracies. Of the 460 records identified, 32 studies were included, of which 50% (16/32) were low risk of bias. The overall pooled sensitivity was 92.2% (95% CI 87.3-95.3%), and specificity was 91.7% (85.2-95.5%). The positive likelihood ratio was 11.1 (4.5-17.8), and the negative likelihood ratio was 0.09 (0.04-0.13). The pooled diagnostic odds ratio was 130.3 (20.5-240). Heterogeneity was moderate on visual inspection of the hierarchical summary receiver operating characteristic curve. Subgroup analyses showed prospective studies reporting higher accuracies (p=0.027), which were driven by higher specificity (prospective 93.1% (88.4-96.0%) versus retrospective 81.2% (81.0-81.4%)). There was no difference in subgroups comparing patient age (p=0.693), number of radiologists interpreting MRI (p=0.503), or risk of bias (p=0.074). No publication bias was detected (p=0.98). In conclusion, non-EPI is a highly sensitive and specific diagnostic test able to identify recurrent cholesteatomas of moderate to large sizes. This test can be considered a non-invasive alternative to second-look surgery.

The Clinical Role of Diffusion-Weighted MRI for Detecting Residual Cholesteatoma in Canal Wall up Mastoidectomy

OBJECTIVES

The purpose of this study was to assess the value of the diffusion MRI with the non-echoplanar imaging (Non-EPI) technique for follow-up the post-operative patients to detect residual cholesteatomas.

STUDY DESIGN

This prospective study was performed on 40 patients. All patients were at least one year after Canal Wall Up mastoidectomy surgery for cholesteatoma and scheduled for a second-look surgery.

PATIENTS AND METHODS

This prospective study was performed on 40 patients. All patients were subjected to Canal Wall Up surgery and planned for the second-look operation. After one year as removal of choleasteatoma is uncertain in first surgery. The study done at Tertiary referral centers (Ain shams, Mansoura, and Minia university hospitals), non-echoplanar diffusion MRI (NEP-DWI) technique for follow-up the post-operative patients to detect residual cholesteatomas, then second look surgery done 2 weeks after MRI.

RESULTS

Forty patients underwent MRI with Non-echoplanar diffusion-weighted imaging (NEP-DWI). Twenty-six patients had positive MRI results with the remaining 14 patients had negative results. These results were compared to operative findings. All positive MRI cases showed positive intra-operative findings. Ten of negative MRI cases showed negative intra-operative findings. Four of DWI-negative cases showed small cholesteatomas.

CONCLUSION

The use of NEP-DWI is a valuable tool in detecting residual cholesteatoma that could replace the second look surgery in many cases.

Proposal of a magnetic resonance imaging follow-up protocol after cholesteatoma surgery: a prospective study

BACKGROUND

Non-echo planar (EPI) diffusion-weighted (DW) MRI has become an effective tool for the follow-up after cholesteatoma surgery and decreased the rate of second-look surgeries.

OBJECTIVES

To shed light on the optimal imaging follow-up protocol to detect postoperative residual or recurrent cholesteatoma.

MATERIALS AND METHODS

64 patients were included in this prospective study. Three different surgical procedures were considered: canal-wall-up (26 patients), canal-wall-down (20 patients), and obliterative (18 patients). The imaging follow-up protocol included non-EPI DW MRI during the following postoperative periods: 1 month, 6 months, and 1, 3, 5, and 7 years after the primary surgery.

RESULTS

MRI-positive lesions were present in 18.75% of patients. 50% of the MRI-positive findings occurred at the 1-month follow-up. The other peak of MRI positivity occurred at the 3-year follow-up. The last MRI-positive finding appeared at the 5-year follow-up.

CONCLUSIONS

The timing for the imaging protocol proposed by this prospective study to detect recidivism after cholesteatoma surgery stressed the importance of performing non-EPI DW MRI for detecting residual, though rare, disease. Likewise, extending the follow-up to a least 5 years after primary surgery was also recommended to detect any recurrent cholesteatoma that would appear unlikely to be present beyond this time set.

The Role of Fusion Technique of Computed Tomography and Non-echo-planar Diffusion-weighted Imaging in the Evaluation of Surgical Localization of Cholesteatoma

Objective:

In recent years, the fusion of computed tomography (CT) and non-echo-planar diffusion-weighted magnetic resonance imaging (non- EPI DWI) has been preferred in cholesteatoma localizations. This study aimed to investigate the role of CT and non-EPI DWI fusion imaging in cholesteatoma localizations.

Methods:

This retrospective study included 39 patients who underwent chronic otitis media operation [mean age of 35.10±15.33 years (18-67 years), 64.1% female, and 35.9% male] and had preoperative high-resolution temporal bone CT and non-EPI DWI examinations. Images were sent to the Advantage Workstation VolumeShare 7 for fusion. These selected images were fused on the workstation and were manually corrected by the radiologist. The sensitivity, specificity, positive and negative predictive values, and diagnostic accuracies of fused images of CT and non-EPI DWI were evaluated according to anatomic cholesteatoma localizations based on surgical data.

Results:

The sensitivity, specificity, positive and negative predictive values, and diagnostic accuracies of non-EPI DWI for detecting cholesteatomas were 97.14%, 75.00%, 97.14%, 75.00%, and 94.87%, respectively. Three true-negative, one false-positive, and one false-negative case were observed according to surgical results in detecting the presence of a cholesteatoma with non-EPI DWI. Moderate agreement was determined between the surgical and radiological results in detecting the presence of a cholesteatoma (k=0.721). Detecting the lesion of localization on the fused images compared to surgical found an almost perfect agreement in the mastoid antrum (k=0.948), strong agreement in the hypotympanum and mastoid cells (k=0.894), moderate agreement in the epitympanum (k=0.653), and weak agreement in those in the mesotympanum (k=0.540).

Conclusions:

The surgeons’ determinations are supported by the guidance of temporal CT and non-EPI DWI fused images. Therefore, preferring the fusion imaging technique could increase the quality of life by reducing unnecessary operations.

Radiological Follow-up After the Bony Obliteration Tympanoplasty in Detecting Residual Cholesteatoma: Towards an Optimal Postoperative MR Imaging Protocol

INTRODUCTION AND AIM

There is no consensus in literature on the most optimal follow-up imaging protocol for non-echoplanar diffusion-weighted magnetic resonance imaging (non-EP DW MRI) after the canal wall-up bony obliteration tympanoplasty. Clearly, no residual cholesteatoma should be missed but on the other hand, unnecessary MR controls should be avoided. The aim of this study is to evaluate the postoperative results of non-EP DW MRI after canal wall-up bony obliteration tympanoplasty surgery at our Institute and to propose an optimal postoperative MR imaging scheme based on our data.

MATERIAL AND METHODS

Retrospective cohort study; all 271 patients who underwent the bony obliteration tympanoplasty between January 2010 and January 2016 with follow-up at our Institute were included. A postoperative MR imaging was systematically performed at 1 year after surgery and repeated at either 5 or both 3 and 5 years after surgery, based on the preferences of the surgeon. Variables of interest were retrieved from electronic patient records.

RESULTS

The median follow-up time was 60 months (inter-quartile range 56-62 mo). Two hundred seventy-one patients (100%) received a 1-year MRI, 107 (39%) a 3-year MRI, and 216 (79.7%%) a 5-year MRI. Residual cholesteatoma was found in nine cases (3.3%), corresponding with an estimated residual rate at 5 years follow-up of 3.7% when using Kaplan-Meier analysis. Of these nine cases, six cases of residual cholesteatoma (66.7%) were detected at the 1-year MRI (12-14 mo postsurgery), two cases (22.2%) at the 3-year MRI (35-39 mo postsurgery), and one case (11.1%) at the 5-year MRI (51 mo postsurgery, in this patient no 3-year MRI was performed). An uncertain MRI result was found in 15 cases, presenting as relatively hyperintense lesions. However, subsequent follow-up scans did not show persistent evidence for residual disease in 14 of these 15 cases.

CONCLUSIONS

A postoperative MRI scan after 1 and 5 years is essential to detect early and late residual cholesteatoma. In our cohort, 22.2% of residual cases were detected at the 3-year MRI. However, this percentage could potentially have been higher when all patients would have received a 3-year MRI. Therefore, in order to detect residual disease as soon as possible, we propose to perform an MRI scan at 1, 3, and 5 years after the bony obliteration tympanoplasty. In cases with an unclear MR result, we suggest a repeat MRI after 12 months.

Optimal Duration of MRI Follow-up to Safely Identify Middle Ear Residual Cholesteatoma

BACKGROUND AND PURPOSE

Previous studies have demonstrated the usefulness of non-EPI DWI for detection of residual cholesteatoma. However, limited data are available to determine the suitable duration of imaging follow-up after a first MR imaging with normal findings has been obtained. The present study aimed to determine the optimal duration of non-EPI DWI follow-up for residual cholesteatoma.

MATERIALS AND METHODS

A retrospective, monocentric study was performed between 2013 and 2019 and included all participants followed up after canal wall up tympanoplasty with at least 2 non-EPI DWI examinations performed on the same 1.5T MR imaging scanner. MR images were reviewed independently by 2 radiologists. Sensitivity and specificity values were calculated as a function of time after the operation. Receiver operating characteristic curves were analyzed to determine the optimal follow-up duration.

RESULTS

We analyzed 47 MRIs from 17 participants. At the end of the individual follow-up period, a residual cholesteatoma had been found in 41.1% of cases. The follow-up duration ranged from 20 to 198 months (mean, 65.9 [SD, 43.9] months). Participants underwent between 2 and 5 non-EPI DWI examinations. Analyses of the receiver operating characteristic curves revealed that the optimal diagnostic value of non-EPI DWI occurred 56 months after the operation when the first MR imaging performed a mean of 17.3 (SD, 6.8) months after the operation had normal findings (sensitivity = 0.71; specificity = 0.7, Youden index = 0.43).

CONCLUSIONS

Repeat non-EPI DWI is required to detect slow-growing middle ear residual cholesteatomas. We, therefore, recommend performing non-EPI DWI for at least the first 5 years after the initial operation.

Diffusion-Weighted Imaging of the Head and Neck (Including Temporal Bone)

Diffusion techniques provide valuable information when performing head and neck imaging. This information can be used to detect the presence or absence of pathology, refine differential diagnosis, determine the location for biopsy, assess response to treatment, and prognosticate outcomes. For example, when certain technical factors are taken into consideration, diffusion techniques prove indispensable in assessing for residual cholesteatoma following middle ear surgery. In other scenarios, pretreatment apparent diffusion coefficient values may assist in prognosticating outcomes in laryngeal cancer and likelihood of response to radiation therapy. As diffusion techniques continue to advance, so too will its clinical utility.

New Compartmental Reading Method for MRI Enables Accurate Localization of Cholesteatomas With High Sensitivity and Specificity

OBJECTIVES

Cholesteatoma is an inflammatory disease, frequently observed in childrens and young adults, with a risk of relapse or recurrence. The few studies which analyzed cholesteatoma localization on magnetic resonance imaging (MRI) usually merged CT-MR images or relied on their authors' anatomical knowledge. We propose a compartmental reading method of the compartments of the middle ear cavity for an accurate localization of cholesteatomas on MR images alone.

MATERIAL AND METHODS

Our method uses easily recognizable anatomical landmarks, seen on both computed tomography (CT) and MRI, to delimit the middle ear compartments (epitympanum, mesotympanum, hypotympanum, retrotympanum, protympanum, antrum-mastoid cavity). We first tested it on 50 patients on non-enhanced temporal bone CT. Then, we evaluated its performances for the localization of cholesteatomas on MRI, compared with surgery on 31 patients (validation cohort).

RESULTS

The selected anatomical landmarks that delimited the middle ear compartments were applicable in 98 to 100% of the cases. In the validation cohort, we were able to accurately localize the cholesteatoma on MRI in 83% of the cases (n = 26) with high sensitivity (95.7%) and specificity (98.6%).

CONCLUSION

With our compartmental reading method, based on the recognition of well-known anatomical landmarks to differentiate the compartments of the middle ear cavity on MRI, we were able to accurately localize the cholesteatoma with high (>90%) sensitivity and specificity. Such landmarks are widely applicable and only require limited learning time based on key images. Accurate localization of the cholesteatoma is useful for the choice of surgical approach.

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.

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.

Negative Predictive Value of Non-Echo-Planar Diffusion Weighted MR Imaging for the Detection of Residual Cholesteatoma Done at 9 Months After Primary Surgery Is not High Enough to Omit Second Look Surgery

OBJECTIVES

To evaluate non echo-planar diffusion weighted magnetic resonance imaging (non-EP DW MRI) at 9 months after primary surgery to rule out residual cholesteatoma in patients scheduled before second-look-surgical exploration.

STUDY DESIGN

Prospective observational study.

SETTING

Secondary teaching hospital.

PATIENTS/INTERVENTIONS

Patients who were scheduled for second-look-surgery after primary canal wall up repair of cholesteatoma underwent 1.5 T MRI including non-EP DWI and high-resolution coronal T1 and T2-FS SE sequences.

MAIN OUTCOME MEASURES

Imaging studies were evaluated for the presence of cholesteatoma by three independent observers. Intraoperative observations were regarded the standard of reference. Ear, nose, throat (ENT) surgeons were blinded for imaging findings. The primary outcome was the negative predictive value (NPV) of MR imaging, secondary outcomes were sensitivity, specificity, and positive predictive value.

RESULTS

Thirty-three patients underwent both MRI and surgery, among whom 22 had a cholesteatoma. Mean time between primary surgery and MRI was 259 days (standard deviation [SD] 108). NPV of non-EP DW MRI in detecting recurrent cholesteatoma was 53% (95% CI: 32-73%). Sensitivity and specificity were 59% (39-77%) and 91% (62-98%), respectively. The positive predictive value was 93% (69-99%). In five out of nine false-negative cases, recurrent cholesteatoma measured 3 mm or less. Using a 3 mm detection threshold, NPV increased to 79%.

CONCLUSION

Non-EP DW MRI cannot replace second look surgery in ruling-out residual cholesteatoma at 9 months after primary surgery. It could be used in a follow-up strategy in low risk patients. Further research is needed which types of residual cholesteatoma are not revealed by MRI.

Surgical mapping of middle ear cholesteatoma with fusion of computed tomography and diffusion-weighted magnetic resonance images: Diagnostic performance and interobserver agreement

OBJECTIVE

To assess the diagnostic performance in detecting primary cholesteatoma at various anatomical subsites using Computed Tomography (CT), Diffusion-weighted Magnetic Resonance Imaging (DWMRI) and Fusion of CT and DWMRI (Fusion CT-MRI) images.

STUDY DESIGN

A retrospective study of 22 children identified from a prospective database of surgically treated cholesteatoma cases over a five year period. All cases underwent pre-operative CT, non-echo planar DWMRI and Fusion CT-DWMRI, and with clearly documented surgical findings. For each imaging modality, two radiologists scored for the presence or absence of cholesteatoma with confidence levels at different anatomical subsites. The radiologists were blinded to the surgical findings to which their findings were compared.

SETTING

Large Teaching Hospital in London.

PATIENTS

22 children with cholesteatoma confirmed surgically.

INTERVENTION

CT, DWMRI imaging and fusion CT-MRI.

MAIN OUTCOME MEASURE

Diagnostic performance of subsite localisation of cholesteatoma by CT, DWMRI and fusion CT-MRI imaging with intra-operative findings.

RESULTS

Twenty-two patients were included (12 women and 10 men). The median age of patients was 11 years. When considering all subsites combined, the result for all imaging methods suggested 'good' agreement between both observers. When all subsites were examined together, all methods had relatively high sensitivity values (87% for CT vs 84% for DWMRI vs 85% for fusion CT-DWMRI). Specificity was highest with fusion CT-DWMRI (46% for CT vs 76% for DWMRI vs 97% for fusion CT-DWMRI), as was accuracy (66% for CT vs 80% for DWMRI vs 91% for fusion).

CONCLUSIONS

Our study has demonstrated that fusion CT-DWMRI is superior to DWMRI or CT separately in localizing cholesteatoma at various middle ear cleft subsites and bony relations, making it a valuable tool for surgical planning.

The utility of computed tomography and diffusion-weighted magnetic resonance imaging fusion in cholesteatoma: illustration with a UK case series

OBJECTIVE

Post-processing imaging techniques allow high-resolution computed tomography and diffusion-weighted magnetic resonance imaging of the temporal bone to be superimposed and viewed simultaneously (fusion imaging). This study aimed to highlight the practical utility of fusion imaging for disease localisation and evaluation in a UK case series of primary and post-operative cholesteatoma.

METHOD

Fusion of computed tomography and diffusion-weighted magnetic resonance b1000 images was performed using specific software. Axial computed tomography images and coronal b1000 images were selected for fusion.

RESULTS

A case series of primary and post-operative cholesteatoma in which computed tomography and magnetic resonance imaging fusion assisted the management of both the patient pathway and surgical approach is reviewed.

CONCLUSION

Computed tomography and magnetic resonance imaging fusion can assist in pre-operative surgical planning and patient counselling through assessment of disease in both primary and revision scenarios. Computed tomography and magnetic resonance imaging fusion can assist the operative surgeon through accurate localisation that can influence both the operative technique and optimise operation theatre utilisation.

Using Non-Echoplanar Diffusion Weighted MRI in Detecting Cholesteatoma Following Canal Wall Down Mastoidectomy - Our Experience with 20 Patient Episodes

OBJECTIVE

To our knowledge, there is no study exploring specifically the diagnostic performance of diffusion-weighted imaging (DWI) in patients with previous canal wall down (CWD) surgery when combined with appropriate clinical evaluation. The aim of the present study was to evaluate the performance of DWI in the detection of residual or recurrent disease in patients who have had a previous CWD mastoidectomy.

MATERIALS AND METHODS

We identified 13 patients with a CWD mastoidectomy subsequently having at least one further DWI prior to further mastoid exploration that generated a total of 20 patient episodes. Magnetic resonance imaging was performed on a 1.5 T superconductive unit using a standard head matrix coil. Coronal 2 mm thick TSE T2-weighted images (TR: 4640 ms; TE: 103 ms; matrix: 245,384; field of view: 150×200 mm) were performed. Operative findings were reviewed for all 20 patient episodes to compare DWI findings with intraoperative findings. Based on this, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated.

RESULTS

DWI had a sensitivity of 93%, specificity of 60%, PPV of 87%, NPV of 75%, and accuracy of 80%.

CONCLUSION

Given the high sensitivity of DWI in the detection of residual or recurrent disease, the present study supports DWI as a useful tool in the detection of residual or recurrent cholesteatoma in cases following CWD surgery, where clinical acumen suggests an ongoing disease process despite no overt cholesteatoma being visible.

Accuracy of turbo spin-echo diffusion-weighted imaging signal intensity measurements for the diagnosis of cholesteatoma

PURPOSE

We aimed to evaluate the diagnostic accuracy of turbo spin-echo diffusion-weighted imaging (TSE-DWI) at 3 T, for cholesteatoma (CS) diagnosis, using qualitative and quantitative methods with numerical assessment of signal intensity (SI), signal intensity ratios (SIR), and apparent diffusion coefficient (ADC) values.

METHODS

In this retrospective study, two blinded observers independently evaluated the preoperative TSE-DWI images of 57 patients who were imaged with a presumed diagnosis of CS. Qualitative assessment with respect to the SI of the adjacent cortex and quantitative measurements of SI, SIR, and ADC values were performed.

RESULTS

Surgery with histopathologic examination revealed 30 CS patients and 27 patients with non-cholesteatoma (NCS) lesions including chronic inflammation and cholesterol granuloma. On TSE-DWI, 96.7% of the CS lesions and none of the NCS lesions appeared hyperintense compared with the cortex. The mean SI and SIR indices of the CS group were significantly higher and the mean ADC values significantly lower compared with those of the NCS group (P < 0.001). Using specific cutoff values for SI (92.5) and SIR (0.9), CS could be diagnosed with 100% sensitivity and specificity. The use of quantitative imaging further increased the sensitivity of the TSE-DWI technique.

CONCLUSION

The quantitative indices of SI, SIR, and ADC of TSE-DWI appear to be highly accurate parameters that can be used to confirm the diagnosis of CS.

Does non-echo-planar diffusion-weighted magnetic resonance imaging have a role in assisting the clinical diagnosis of cholesteatoma in selected cases?

OBJECTIVE

To determine the diagnostic performance of diffusion-weighted magnetic resonance imaging in the assessment of patients with suspected, but not clinically evident, cholesteatoma.

METHODS

A retrospective analysis of a prospectively collected database of non-echo-planar diffusion-weighted magnetic resonance imaging studies (using a half-Fourier single-shot turbo-spin echo sequence) was conducted. Clinical records were retrospectively reviewed to determine indications for imaging and operative findings. Seventy-eight investigations in 74 patients with suspected cholesteatoma aged 5.7-79.2 years (mean, 41.7 years) were identified. Operative confirmation was available in 44 ears. Diagnostic accuracy of the imaging technique was calculated using operative findings as a 'gold standard'. Sensitivity of the investigation was examined via comparison with clinically evident cholesteatoma.

RESULTS

The accuracy of diffusion-weighted magnetic resonance imaging in assessment of suspected cholesteatoma was 63.6 per cent. The imaging technique was significantly less accurate in assessment of suspected cholesteatoma than clinically evident disease (p < 0.001).

CONCLUSION

Computed tomography and diffusion-weighted magnetic resonance imaging may be complementary in assessment of suspected cholesteatoma, but should be used with caution, and clinical judgement is paramount.

Temporal bone computed tomography findings associated with feasibility of endoscopic ear surgery

PURPOSE

There are no formal radiologic criteria to stratify patients for transcanal (TEES) or transmastoid endoscopic ear surgery for resection of cholesteatoma. We aim to determine 1) whether standard preoperative computed tomography (CT) findings are associated with the need for conversion to a transmastoid approach and 2) the amount of time added for conversion from TEES to transmastoid techniques.

MATERIALS AND METHODS

Retrospective chart review of consecutive pediatric and adult cases of TEES for primary cholesteatoma from 2013 through 2015 (n=52). TEES cases were defined as endoscope-only procedures that did not require a transmastoid approach (n=33). Conversion cases were defined as procedures that began as TEES however, required conversion to a transmastoid approach due to the inability to complete cholesteatoma removal (n=19). Preoperative CT findings and total operating room (OR) times of TEES and conversion cases were compared.

RESULTS

Preoperative CT scan characteristics that were associated with conversion included tegmen erosion (p=0.026), malleus erosion (p<0.001), incus erosion (p=0.009), mastoid opacification (p=0.009), soft tissue opacification extending into the aditus ad antrum (p=0.009) and into antrum (p=0.006). Total OR time for TEES cases was significantly shorter than conversion cases (median 143min versus 217min, p<0.001).

CONCLUSIONS

Preoperative CT findings, notably extension of soft tissue in the aditus ad antrum, antrum and mastoid, are associated with need for conversion to transmastoid technique to achieve removal of cholesteatoma. Endoscope-only cases were significantly faster than cases that required conversion to a transmastoid approach.

Monitoring Progression of 12 Cases of Non-Operated Middle Ear Cholesteatoma With Non-Echoplanar Diffusion Weighted Magnetic Resonance Imaging: Our Experience

AIM

The aim of this study is to gain insight into the disease progression and behavior of primary cholesteatoma in a cohort of patients who did not have surgery using non-echoplanar diffusion-weighted magnetic resonance imaging (DW MRI) serial monitoring.

METHODS

Retrospective longitudinal observational study of 12 cases of middle ear cleft cholesteatoma diagnosed between 2009 and 2014 where surgery was not performed for various reasons. All cases were monitored radiologically with non-echoplanar half-Fourier acquisition single-shot turbo spin-echo diffusion weighted imaging annually for a median period of 23 months (between 11 and 45 mo) to evaluate for changes in disease volume and direction of growth.

RESULTS

Of the 12 cases, there was one outlier where the cholesteatoma growth was disproportionately high compared with the rest of the cases outside the standard deviation range. A third of the cases had radiological evidence of cholesteatoma growth. The mean growth was about 11.9% of the initial disease volume per year. Seven out of the 12 cases had radiological evidence of cholesteatoma regression in terms of size, with three cases having negative follow-up DW-MRI scans as early as 17 months. The mean regression rate was much higher than the mean growth rate at 54.3% of the initial disease volume per year. The direction of greatest growth is craniocaudally.

CONCLUSION

Within the limits of our longitudinal study, we have shown that by monitoring with non-echoplanar diffusion weighted imaging, cholesteatoma can progress or regress when left untreated by surgery. The greatest progression was recorded in the craniocaudal direction.

Non-echoplanar diffusion weighted imaging in the detection of post-operative middle ear cholesteatoma: navigating beyond the pitfalls to find the pearl

Abstract

Non-echoplanar diffusion weighted magnetic resonance imaging (DWI) has established itself as the modality of choice in detecting and localising post-operative middle ear cleft cholesteatoma. Despite its good diagnostic performance, there are recognised pitfalls in its radiological interpretation which both the radiologist and otologist should be aware of. Our article highlights the various pitfalls and provides guidance for improving radiological interpretation and navigating beyond many of the pitfalls. It is recommended radiological practice to interpret the diffusion weighted images together with the ADC map and supplement with the corresponding T1 weighted and T2 weighted images, all of which can contribute to and enhance lesion localisation and characterisation. ADC values are also helpful in improving specificity and confidence levels. Given the limitation in sensitivity in detecting small cholesteatoma less than 3 mm, serial monitoring with DWI over time is recommended to allow any small residual cholesteatoma pearls to grow and become large enough to be detected on DWI. Optimising image acquisition and discussing at a joint clinico-radiological meeting both foster good radiological interpretation to navigate beyond the pitfalls and ultimately good patient care.

Teaching Points

• Non-echoplanar DWI is the imaging of choice in detecting post-operative cholesteatoma.

• There are recognised pitfalls which may hinder accurate radiological interpretation.

• Interpret with the ADC map /values and T1W and T2W images.

• Serial DWI monitoring is of value in detection and characterisation.

• Optimising image acquisition and discussing at clinico-radiological meetings enhance radiological interpretation.

Imaging innovations in temporal bone disorders

The development of new imaging techniques coupled with new treatment algorithms has created new possibilities in treating temporal bone diseases. This article provides an overview of recent imaging innovations that can be applied to temporal bone diseases. Topics covered include the role of magnetic resonance (MR) diffusion-weighted imaging in cholesteatomas and skull base epidermoids, whole-body molecular imaging in paragangliomas of the jugular foramen, and MR arterial spin labeling perfusion for dural arteriovenous fistulas and arteriovenous malformations.

Comparing diffusion weighted MRI in the detection of post-operative middle ear cholesteatoma in children and adults

INTRODUCTION

There is a limited evidence base for the use of diffusion weighted MRI (DWMRI) in the assessment of post-operative cholesteatoma in children. This is important to address as this technique is particularly relevant in a paediatric setting.

METHODS

We searched a prospectively collected database of patients undergoing DWMRI for the assessment of residual and recurrent cholesteatoma. Imaging findings were correlated with findings at revision surgery. 320 investigations were divided into paediatric and adult groups (90 in children, 230 in adults) and compared.

RESULTS

Operative findings were available for 158 cases, of which 54 were children. The accuracy of DWMRI in children was 96.3%, and in adults was 88.5%. There were no statistically significant differences in the sensitivity, specificity, positive or negative predictive values between adults and children.

DISCUSSION

An increasing number of patients are not undergoing confirmatory surgery after negative DWMRI scans. False negative results are commonly secondary to small foci of disease; false positives have several possible causes. Performing MRI on children can be challenging, but sedation may be helpful in younger children.

CONCLUSION

The performance of diffusion weighted MRI is similar in paediatric and adult settings. This study suggests that DWMRI may be used in clinical practice in a similar way in children and adults.

A Systematic Review of Non-Echo Planar Diffusion-Weighted Magnetic Resonance Imaging for Detection of Primary and Postoperative Cholesteatoma

Objective

To investigate the diagnostic value of non–echo planar diffusion-weighted magnetic resonance imaging (DW-MRI) for primary and recurrent/residual (postoperative) cholesteatoma in adults (≥18 years) after canal wall up surgery.

Data Sources

We conducted a systematic search in PubMed, Embase, and Cochrane up to October 22, 2014.

Review methods

All studies investigating non–echo planar DW-MRI for primary and postoperative cholesteatoma were selected and critically appraised for relevance and validity.

Results

In total, 779 unique articles were identified, of which 23 articles were included for critical appraisal. Seven articles met our criteria for relevance and validity for postoperative cholesteatoma. Four studies were additionally included for subgroup analysis of primary cases only. Ranges of sensitivity, specificity, positive predictive value, and negative predictive value yielded 43%-92%, 58%-100%, 50%-100% and 64%-100%, respectively. Results for primary subgroup analysis were 83%-100%, 50%-100%, 85%-100%, and 50%-100%, respectively. Results for subgroup analysis for only postoperative cases yielded 80%-82%, 90%-100%, 96%-100%, 64%-85%, respectively. Despite a higher prevalence of cholesteatoma in the primary cases, there was no clinical difference in added value of DW-MRI between primary and postoperative cases.

Conclusion

We found a high predictive value of non–echo planar DW-MRI for the detection of primary and postoperative cholesteatoma. Given the moderate quality of evidence, we strongly recommend both the use of non-echo planar DW-MRI scans for the follow-up after cholesteatoma surgery, and when the correct diagnosis is questioned in primary preoperative cases.

Correlation of computed tomography, echo-planar diffusion-weighted magnetic resonance imaging and surgical outcomes in middle ear cholesteatoma

CONCLUSION

Echo-planar diffusion-weighted magnetic resonance imaging (DW MRI) is more reliable than high-resolution computed tomography (HRCT) in predicting the presence and localization of cholesteatoma before tympanomastoid surgery.

OBJECTIVES

To evaluate the diagnostic accuracy of HRCT and echo-planar DW MRI in the detection and localization of cholesteatoma.

METHODS

Fifty-nine patients were prospectively included in this study. Patients with suspected primary cholesteatoma were evaluated by HRCT and echo-planar DW MRI before tympanomastoid surgery. Radiological findings were correlated with intraoperative findings.

RESULTS

HRCT and echo-planar DW MRI accurately predicted the presence or absence of cholesteatoma in 40/59 (67.8%) and 52/59 (88.1%) patients, respectively. The sensitivity, specificity, and positive and negative predictive values of HRCT were 68.97%, 66.67%, 66.67%, and 68.97%, respectively. However, sensitivity, specificity, and positive and negative predictive values of echo-planar DW MRI were 85.71%, 90.32%, 88.89%, and 87.50%, respectively.

Non-echoplanar diffusion-weighted MRI in children and adolescents with cholesteatoma: reliability and pitfalls in comparison to middle ear surgery

BACKGROUND

Currently, there is only limited and contradictory evidence of the role of diffusion-weighted MRI (DW-MRI) in the management of children with cholesteatoma.

OBJECTIVE

To provide surgically controlled data that may allow to replace second-look surgery by non-echoplanar DW-MRI in children.

MATERIALS AND METHODS

Fifty-five children and adolescents with a median age of 8.6 years (2.2-17.7 years) underwent 61 preoperative half-Fourier acquisition single-shot turbo spin-echo (HASTE) DW-MRI of their petrous bone. Surgical interventions followed within 24 h (79%), within 5 months (20%) or at 18 months (1 case).

RESULTS

Surgery detected a cholesteatoma or retraction pocket in 41 of 61 cases (67%). In 49 cases (80%), the MR result was confirmed by surgical findings. Two MR findings were false-positive and 10 false-negative (including cholesteatomas <4 mm). HASTE DW-MRI alone had a sensitivity of 76% and a specificity of 90%. The positive predictive value was 94%, the negative predictive value 64%. In combination with preoperative otoscopy, sensitivity was 90% and negative predictive value 82%.

CONCLUSION

DW-MRI correctly detected the majority of lesions but could not reliably exclude small cholesteatomas and empty retraction pockets. We would therefore not generally recommend MR as a substitute for second-look surgery.

Diagnostic capacity of non-echo planar diffusion-weighted MRI in the detection of primary and recurrent cholesteatoma

INTRODUCTION AND AIMS

the aim of this study was to determine the certainty of non-echo-planar imaging diffusion-weighted magnetic resonance imaging (non-EPI DW MRI) in the diagnosis of primary and recurrent cholesteatoma in patients with clinical suspicion of cholesteatoma, assessing the sensitivity and specificity of the test in both groups.

METHODS

Seventy-five patients with clinical suspicion of cholesteatoma were included in our study. Forty-eight cases had primary suspicion of cholesteatoma and 27 cases had recurrent suspicion of cholesteatoma. All patients received non-EPI DW MRI tests before surgery, and radiological and surgical findings were compared.

RESULTS

Sensitivity, specificity and the positive and negative predictive value for primary diagnosis of cholesteatoma group were 91.2%, 50%, 81.6% and 70%, respectively. For the recurrent cholesteatoma group these results were 100%, 66.7%, 90.9% and 100%, respectively.

CONCLUSION

Non-echo-planar imaging diffusion-weighted magnetic resonance imaging is a high sensitivity imaging test for detecting cholesteatoma, for both primary diagnosis and for recurrent cases.

Diffusion weighted MR imaging of primary and recurrent middle ear cholesteatoma: an assessment by readers with different expertise

Introduction and Purpose. Diffusion weighted imaging (DWI) has been proven to be valuable in the diagnosis of middle ear cholesteatoma. The aims of our study were to evaluate the advantage of multi-shot turbo spin echo (MSh TSE) DWI compared to single-shot echo-planar (SSh EPI) DWI for the diagnosis of cholesteatoma. Material and Methods. Thirty-two patients with clinical suspicion of unilateral cholesteatoma underwent preoperative MRI (1.5T) with SSh EPI and MSh TSE. Images were separately analyzed by 4 readers with different expertise to confirm the presence of cholesteatoma. Sensitivity, specificity, diagnostic accuracy, and positive (PPV) and negative predictive values (NPV) were assessed for each observer and interrater agreement was assessed using kappa statistics. Diagnosis was obtained at surgery. Results. Overall MSh TSE showed higher diagnostic accuracy and lower negative predictive value (NPV) compared to conventional SSh EPI. Interreader agreement between the observers revealed the superiority of MSh TSE compared to SSh EPI. Interrater agreement among all the four observers was higher by using MSh TSE compared to SSh EPI. Conclusion. Our findings suggest that MSh TSE DWI has higher sensitivity for detection of cholesteatoma and lower probability of misdiagnosis. MSh TSE DWI is useful in guiding less experienced observers to the diagnosis.

Use of non-echo-planar diffusion-weighted MR imaging for the detection of cholesteatomas in high-risk tympanic retraction pockets

BACKGROUND AND PURPOSE

Non-echo-planar DWI MR imaging (including the HASTE sequence) has been shown to be highly sensitive and specific for large cholesteatomas. The purpose of this study was to determine the diagnostic accuracy of HASTE DWI for the detection of incipient cholesteatoma in high-risk retraction pockets.

MATERIALS AND METHODS

This was a prospective study of 16 patients who underwent MR imaging with HASTE DWI before surgery. Surgeons were not informed of the results, and intraoperative findings were compared against the radiologic diagnosis. Sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

Among the 16 retraction pockets, 10 cholesteatomas were diagnosed intraoperatively (62.5%). HASTE showed 90% sensitivity, 100% specificity, 100% positive predictive value, and 85.7% negative predictive value in this group of patients. We found only 1 false-negative finding in an infected cholesteatoma.

CONCLUSIONS

We demonstrate a high correlation between HASTE and surgical findings, suggesting that this technique could be useful for the early detection of primary acquired cholesteatomas arising from retraction pockets and could help to avoid unnecessary surgery.

Imaging for evaluation of cholesteatoma: current concepts and future directions

PURPOSE OF REVIEW

To examine the rationale and utility of imaging in patients with known or suspected cholesteatoma, with emphasis on high-resolution computed tomography (HRCT) and diffusion-weighted MRI (DW-MRI).

RECENT FINDINGS

The initial diagnosis of cholesteatoma is largely based on patient history and clinical findings. HRCT scan can be a useful adjunct to define the presence of pathologic soft tissue in the temporal bone, and the extent of bony erosion, and inform the otologic surgeon about expected findings at the time of surgery. Although MRI has not traditionally been used in the evaluation of cholesteatoma given its poor resolution of bone anatomy, recent advances in DW-MRI sequences allow for high sensitivity and specificity in identifying the presence of cholesteatoma. More specifically, non-echo-planar DW-MRI is superior in the detection of residual or recurrent cholesteatoma compared to delayed-contrast MRI and echo-planar DW-MRI.

SUMMARY

HRCT and DW-MRI offer complementary anatomic information that can be used effectively in the management of cholesteatoma. DW-MRI imaging has proven to be a reliable method for detecting residual or recurrent cholesteatomas down to 3 mm in size, and allows radiologic differentiation between cholesteatoma and other soft tissue. As more centers implement DW-MRI imaging for detecting residual or recurrent cholesteatoma, there will likely be less need for second-look surgery, thereby potentially decreasing associated morbidity and surgical costs.

Apparent diffusion coefficients for detection of postoperative middle ear cholesteatoma on non-echo-planar diffusion-weighted images

PURPOSE

To determine whether there is a difference between the apparent diffusion coefficients (ADCs) of postoperative middle ear cleft cholesteatoma and noncholesteatomatous tissue on half-Fourier acquisition single-shot turbo spin-echo diffusion-weighted (DW) images and to determine, with interobserver agreement, a predictive accuracy for diagnosis of postoperative middle ear cleft cholesteatoma.

MATERIALS AND METHODS

Patients who underwent DW magnetic resonance (MR) examination before repeat explorative surgery for postoperative cholesteatoma were included in this study. There were 72 patient episodes and 56 patients. DW MR images were acquired with b values 0 and 1000 sec/mm(2) and 2-mm section thicknesses. Two observers assessed images qualitatively for presence of cholesteatoma and recorded ADCs. Surgery with histologic confirmation established final diagnosis of abnormal middle ear cleft soft tissue. ADCs between cholesteatoma and noncholesteatomatous tissue were compared with Mann-Whitney test. Effects of ADCs and confidence intervals to indicate presence of cholesteatoma were examined by using receiver operating characteristic (ROC) curve analysis, logistic regression analysis, and interobserver agreement.

RESULTS

Forty-six patients had cholesteatoma and 25 patients did not; sensitivity and specificity were 0.91 and 0.88, respectively, for the qualitative diagnosis of postoperative cholesteatoma by using a five-point confidence scale. ADC of cholesteatoma (median, 707 × 10(-6) mm(2)/sec; interquartile range, 539-858 × 10(-6) mm(2)/sec; P < .001) was significantly lower than that of noncholesteatomatous tissue (median, 1849 × 10(-6) mm(2)/sec; interquartile range, 1574-1982 × 10(-6) mm(2)/sec; P < .001). There was good accuracy (area under the ROC curve, 0.97) and interobserver agreement for detecting postoperative cholesteatoma with ADC threshold less than 1300 × 10(-6) mm(2)/sec.

CONCLUSION

The ADC value of postoperative middle ear cleft cholesteatoma is significantly lower than that of noncholesteatomatous tissue and has good accuracy for detecting cholesteatoma.

Can early second-look tympanoplasty reduce the rate of conversion to modified radical mastoidectomy?

CONCLUSIONS

Combined approach tympanoplasty (CAT) allows for successful treatment of cholesteatoma with rates of recurrent and residual disease comparable to open mastoid surgery. Early timing of second-look procedures allows easier removal of any recurrent or residual disease, which reduces the conversion rate to open mastoidectomy.

OBJECTIVES

The aims of the study were to report the rates of recurrent and residual cholesteatoma following primary CAT surgery and to report the rate of conversion to a modified radical mastoidectomy.

METHODS

This was a retrospective review of a single surgeon series between 2006 and 2012.

RESULTS

In total 132 second-look operations were undertaken, with a mean interval between primary surgery and second-look procedures of 6 months. The rate of cholesteatoma at second-look surgery was 19.7%, which was split into residual disease (10.6%) and recurrent disease (9.09%). New tympanic membrane defects with cholesteatoma were considered as recurrent disease. Residual disease was defined as cholesteatoma present behind an intact tympanic membrane. The majority of recurrent and residual disease was easily removed at second look (73.1%). Only four cases were converted to a modified radical mastoidectomy (3%) and three cases required a third-look procedure.