Preliminary outcomes of cholesteatoma screening in children using non-echo-planar diffusion-weighted magnetic resonance imaging

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.

Early Magnetic Resonance Imaging to Diagnose Residual Cholesteatoma in Children and Benefit of Radiological Rereview

OBJECTIVE

Non-echo-planar diffusion-weighted (DW) magnetic resonance imaging (non-EPI MRI) is the appropriate sequence to detect residual cholesteatoma. In the child, MRI may be clinically useful to determine the timing of the second-look procedure. The aim of this paper was to retrospectively evaluate the performance of early MRI (before the 18th postoperative month) in detecting residual cholesteatoma in children after review by experienced specialized neuroradiologists.

STUDY DESIGN

Retrospective study.

SETTING

One university center comparative cohort.

METHODS

All patients who had a 2-staged procedure for cholesteatoma with an MRI before the second stage from 2010 to 2020 were included and analyzed. Three pediatric neuroradiologists reviewed all the images blinded to the surgical result.

RESULTS

N = 141 cholesteatoma events (140 children) were included with a mean age at MRI of 10 (±4) years old. Non-EPI MRIs were performed 10.7 (±3.8) months after the first-stage surgery and 2.2 (±2.6) months before the second-stage procedure. Non-EPI MRI had a 0.57 sensitivity (SE) and 0.83 specificity (SP). MRI was reviewed in 112 cases. The diagnosis was corrected in 17 cases (15.1%) (3 true positives, 7 false negatives, and 7 false positives). SE = 0.63 (p = 0.1) and SP = 0.92 (p = 0.08) after rereading.

CONCLUSION

Early MRI's SE is poor but SP is excellent after rereading. Evidence does not support the use of early non-EPI MRI to modify the surgical strategy or to postpone the second look. If performed, early non-EPI MRI should be read by specialized experienced radiologists with all 3 sequences (T1, T2, and non-EPI DW) and apparent diffusion coefficient calculation, especially in cases of otitis media with effusion.

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.

Diffusion-weighted magnetic resonance imaging for diagnosis of post-operative paediatric cholesteatoma

OBJECTIVES

High rates of recidivism are reported after paediatric cholesteatoma surgery. Our practice has adapted to include non-echoplanar diffusion-weighted magnetic resonance imaging for the diagnosis of residual or recurrent cholesteatoma. This audit aimed to evaluate the performance of non-echoplanar diffusion-weighted magnetic resonance imaging in our paediatric population.

METHODS

A retrospective review was conducted of non-echoplanar diffusion-weighted magnetic resonance imaging scans performed to detect residual disease or recurrence after surgery for cholesteatoma in children from 1 January 2012 to 30 November 2017 in our centre. Follow-up diffusion-weighted magnetic resonance imaging scans were reviewed to 16 August 2019.

RESULTS

Thirty-four diffusion-weighted magnetic resonance imaging scans were included. The sensitivity and specificity values of diffusion-weighted magnetic resonance imaging for detecting post-operative cholesteatoma were 81 per cent and 72 per cent, respectively. Positive predictive and negative predictive values were 72 per cent and 81 per cent, respectively.

CONCLUSION

Use of diffusion-weighted magnetic resonance imaging is recommended as a replacement for routine second-look surgical procedures in the paediatric population. However, we would caution that patients require close follow up after negative diffusion-weighted magnetic resonance imaging findings.

Novel Radiologic Approaches for Cholesteatoma Detection: Implications for Endoscopic Ear Surgery

Technological advancement in computed tomography (CT) and MRI has improved cholesteatoma detection rates considerably in the past decade. Accurately predicting disease location and extension is essential for staging, planning, and preoperative counseling, in particular in the newer approach of endoscopic ear surgery. Improved sensitivity and specificity of these radiological methods may allow the surgeon to confidently monitor patients, therefore avoiding unnecessary surgery. This article outlines recent advances in CT and MRI technology and advantages and disadvantages of the newer techniques. Emphasis on improving the feedback loop between the radiologist and surgeon will increase the accuracy of these new technologies.

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.

Experience with cholesteatoma behind an intact tympanic membrane in children

INTRODUCTION

To systematically investigate all surgeries for cholesteatoma behind an intact tympanic membrane at our department. To identify predictive factors that can help the surgeon to plan surgery, surgical techniques, and follow-up treatment.

MATERIAL AND METHODS

This retrospective study evaluates 21 child patients, who were operated in the period 2007-2017 on for cholesteatoma behind an intact tympanic membrane.

RESULTS

A total of 202 primary operations were performed for cholesteatoma. In 21 cases (10,4%) there was a cholesteatoma behind an intact tympanic membrane and in 11 (5,45%) cases of it there was the congenital cholesteatoma. The most frequently affected area was the anterior-superior quadrant. The preoperative hearing loss increased significantly with disease severity (I-IV by Potsic).

CONCLUSIONS

The classification system according to Potsic is sufficient and fully corresponds to the surgeon's needs. It has been clearly shown that a higher CC stage is associated with worse postoperative hearing results.

Cost-comparison analysis of diffusion weighted magnetic resonance imaging (DWMRI) versus second look surgery for the detection of residual and recurrent cholesteatoma

Background

Cholesteatoma is a destructive, erosive growth of keratinizing squamous epithelium in the middle ear cleft. Following treatment with a canal wall-up (CWU) tympanomastoidectomy, surveillance of residual and recurrent disease has traditionally been achieved through a second look tympanotomy following the initial procedure. Historically, MRI sequences have been inadequate at differentiating between granulation tissue, inflammation, and cholesteatoma. Recent literature has shown diffusion-weighted magnetic resonance imaging (DWMRI) to be a viable alternative to second look surgery for the detection of residual or recurrent disease. The goal of the present study was to perform a cost analysis of DWIMRI versus second look surgery in the detection of residual or recurrent cholesteatoma following combined approach tympanomastoidectomy.

Methods

A probabilistic decision tree model was generated from a literature review to compare traditional second look surgery with DWMRI. Cost inputs were obtained from the Ontario Case Costing Initiative, the Ontario Health Insurance Plan (OHIP) schedule of benefits. Costs were reported in Canadian dollars and a payer perspective was adopted. A probabilistic sensitivity analysis was performed.

Results

According to the probabilistic sensitivity analysis, mean cost difference of traditional second look tympanotomy versus echo planar imaging (EPI) DWMRI was $180.27CAD, 95%CI [$177.32, $188,32] in favour of second-look tympanotomy. However, mean cost difference of traditional second look tympanotomy versus non-EPI DWMRI was $390.66CAD, 95%CI [$381.52, $399.80] in favour of non-EPI DWMRI.

Conclusions

Diffusion-weighted MRI, specifically non-EPI sequences, are a viable cost-saving alternative to second-look tympanotomy in the setting of detecting residual or recurrent cholesteatoma.

Value of DW-MRI in the preoperative evaluation of congenital cholesteatoma

OBJECTIVE

This study evaluated the clinical value of diffusion-weighted magnetic resonance imaging (DW-MRI) in the diagnosis and staging of congenital cholesteatoma (CC).

PATIENTS AND METHODS

We retrospectively reviewed 24 patients with CC. All the patients underwent computed tomography (CT) and DW-MRI preoperatively; thereafter, surgery was performed. DW-MRI examination was performed with a 3 T MRI system using three-dimensional reversed fast imaging with steady-state precession and diffusion-weighted magnetic resonance sequence. The preoperative and operative CT and DW-MRI findings were compared.

RESULTS

Using DW-MRI, cholesteatoma was successfully detected in 17 (71%) of the 24 patients with CC. Among the seven patients with false-negative results, the cholesteatoma mass diameter was <5 mm in six patients and ≥5 mm in one patient. One of these patients had open type congenital cholesteatoma (OTCC). The detection rates for closed type cholesteatoma and OTCC were 85% (17/20) and 0% (0/4), respectively, using DW-MRI. Using CT and DW-MRI, the correct stage was identified in 88% (15/17) and 59% (10/17) of the patients with aeration around the CC and in 0% (0/7) and 100% (7/7) of those without aeration around the CC, respectively.

CONCLUSION

CT is the primary imaging tool for evaluating suspected CC in patients with aeration around the CC. However, CT is unreliable for the detection of the extension and staging of CC when the middle ear is filled with nonspecific imaging. DW-MRI is useful for the preoperative diagnosis and staging of CC > 5 mm in diameter with or without surrounding granulation tissue. Thus, we recommend using DW- MRI at least when CT fails to localize CC as a soft tissue mass because of non-specific tissue filling the middle ear and the mastoid.

Diffusion-weighted magnetic resonance imaging in the detection of residual and recurrent cholesteatoma in children: A systematic review and meta-analysis

OBJECTIVE

To examine the performance of diffusion-weighted magnetic resonance imaging (DW-MRI) in the detection of residual and recurrent cholesteatoma in children.

METHODS

A systematic review and meta-analysis was conducted as per PRISMA guidelines using the following databases from their date of inception: MEDLINE, PubMed, Embase, Cochrane Library, Web of Science. Bivariate meta-analysis using a random effects model was used to calculate summarized pooled estimates of sensitivity, specificity, and diagnostic odds ratios, using second-look surgery as the gold standard comparison.

RESULTS

A total of ten articles (141 cases) were included for qualitative and quantitative analysis. Pooled sensitivity and specificity of non-echo planar imaging (non-EPI) DW-MRI were 89.4% (95%CI 51.9%-98.5%) and 92.9% (95%CI 81.4%-97.5%) respectively. DW-MRI appears limited in its ability to detect lesions less than 3 mm in size.

CONCLUSION

Non-EPI DW-MRI is highly specific but carries uncertain sensitivity in the detection of residual and recurrent cholesteatoma in children. Further research is warranted to determine the specific role of DW-MRI in this patient group, namely when and how often children should be referred for imaging and in which cases the method can be used to completely replace second-look surgery.

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.

Repeated Postoperative Follow-up Diffusion-weighted Magnetic Resonance Imaging to Detect Residual or Recurrent Cholesteatoma

OBJECTIVE

In our institution, follow-up diffusion-weighted imaging (DWI) after cholesteatoma surgery is performed at least twice. The aim of this study was to determine the yield of the second follow-up DWI (D-W MRI-2) in patients in whom the first postoperative DWI (D-W MRI-1) was negative for residual or recurrent cholesteatoma.

STUDY DESIGN

A retrospective analysis.

SETTING

Tertiary referral center.

PATIENTS

Patients were included if 1) they had at least two postoperative DWI examinations after a canal wall up procedure with apparently complete cholesteatoma resection; 2) D-W MRI-1 was performed between 6 and 24 months after surgery and D-W MRI-2 performed at least 6 months after D-W MRI-1; 3) both DWI examinations were of good quality and covering the whole mastoid-middle ear region; 4) D-W MRI-1 was unequivocally negative for cholesteatoma; and 5) there was no clinical suspicion on otoscopy of recurrent cholesteatoma nor a surgical intervention between these two postoperative DWI examinations. In total, 45 separate ears in 44 patients were included.

RESULTS

In 14 ears (31%) D-W MRI-2 was positive (n = 8) or equivocal (n = 6) for cholesteatoma. In six of eight patients with positive D-W MRI-2, follow-up surgery was performed. Cholesteatoma was found in five of them. None of the patients with equivocal findings on D-W MRI-2 was operated on. Patients with positive D-W MRI-2 were of young age. There were no observable differences for sex, side, time between surgery and D-W MRI-1, time between surgery and D-W MRI-2, or time between D-W MRI-1 and D-W MRI-2, or for the location of cholesteatoma at surgery. In the study period there was a trend to perform D-W MRI-1 and D-W MRI-2 earlier after initial surgery. In the same period, there was an evident decrease in average age of the patient population.

CONCLUSION

Despite cholesteatoma surgery without macroscopic residue, clinical follow-up and routine first follow-up DWI without any signs of residual or recurrent disease, repeat follow-up DWI showed evidence of cholesteatoma in 31% of patients. On the basis of the findings in this study, repeated follow-up DWI is recommended.

Diffusion-Weighted Magnetic Resonance Imaging of Cholesteatoma Using PROPELLER at 1.5T: A Single-Centre Retrospective Study

PURPOSE

The purpose of this study was to evaluate the sensitivity, specificity, and positive and negative predictive values of the diffusion-weighted periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique in the detection of cholesteatoma at our institution with surgical confirmation in all cases.

METHODS

A retrospective review of 21 consecutive patients who underwent diffusion-weighted PROPELLER magnetic resonance imaging (MRI) on a 1.5T MRI scanner prior to primary or revision/second-look surgery for suspected cholesteatoma from 2009-2012 was performed.

RESULTS

Diffusion-weighted PROPELLER had a sensitivity of 75%, specificity of 60%, positive predictive value of 86%, and negative predictive value of 43%. In the 15 patients for whom the presence or absence of cholesteatoma was correctly predicted, there were 2 cases where the reported locations of diffusion restriction did not correspond to the location of the cholesteatoma observed at surgery.

CONCLUSION

On the basis of our retrospective study, we conclude that diffusion-weighted PROPELLER MRI is not sufficiently accurate to replace second look surgery at our institution.

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.

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.

Diagnostic accuracy of diffusion-weighted MR imaging versus delayed gadolinium enhanced T1-weighted imaging in middle ear recurrent cholesteatoma: A retrospective study of 39 patients

OBJECTIVE

MR imaging using diffusion-weighted (DW) images and delayed gadolinium-enhanced T1-weighted images is evolving into an alternative to second look surgery in detection of recurrent cholesteatomas. The aim of this study was to retrospectively compare the DW images, the post-gadolinium T1-weighted images and the combination of both methods in this indication.

PATIENTS AND METHODS

We retrospectively evaluated the MR examination of 39 patients clinically suspected for a recurrent cholesteatoma. Patients in the study underwent DW sequences, delayed gadolinium enhanced T1-weighted sequences as well as standard uninjected protocol using T1 and T2 sequences. Three blinded radiologists evaluated three data sets: a set of post-gadolinium T1-weighted images, a set of DW images and a set of the combination of both methods. The interobserver agreement was evaluated and the diagnostic accuracy of each method was described by sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). The performances of the three techniques were also evaluated using ROC curves, from which the AUC were compared. Results were compared with surgical results or a two-year follow-up.

RESULTS

The overall sensitivity and specificity were respectively 63% and 71% for the post-gadolinium T1-weighted images, 88% and 75% for the DW images and 84% and 75% for the combined images. The PPV and NPV were respectively 89% and 33% for the post-gadolinium T1-weighted images, 93% and 62% for the DW images and 93% and 55% for the combined images. The sensitivity and the NPV were significantly different between the three methods (P<0.0001 and P=0.027). There was no statistically significant difference in specificity or PPV between the three methods (P=0.931 and P=0.650). The diagnostic accuracy evaluated with the AUC showed no statistically significant difference between the DW images and the combined images (P=0.433).

CONCLUSION

MR imaging reliably identifies those patients suspected for recurrent cholesteatoma who require a surgical second look by using DW MR imaging. The combination with delayed gadolinium enhanced T1-weighted sequences does not significantly increase the diagnostic accuracy of the examination.

Magnetic resonance imaging at one year for detection of postoperative residual cholesteatoma in children: Is it too early?

OBJECTIVE

To compare the residual cholesteatoma detection accuracy of diffusion-weighted (DW) and T1 delayed sequences for magnetic resonance at one year postoperative with second-look surgery in pediatric patients who have undergone primary middle ear surgery for cholesteatoma.

METHODS

This was a prospective monocentric consecutive study conducted in a tertiary academic referral center. Children were referred for MR imaging (MRI) one year after surgery. A 1.5T MRI was utilized, using nonecho-planar DW images and delayed gadolinium-enhanced T1-weighted images. Accuracy of magnetic resonance imaging was assessed by two radiologists before surgery. Interobserver and intraobserver agreements were assessed using the κ test. Magnetic resonance imaging data were compared with surgery, which was considered as the gold standard.

RESULTS

Twenty-four consecutive unselected pediatric patients were included. Sensitivity, specificity, positive predictive value, and negative predictive value for the first observer were of 40%, 86%, 67%, and 67%, respectively, and those for the second observer were 30%, 86%, 60%, and 63%, respectively. The only two cholesteatoma with a size superior to 3mm were diagnosed before surgery, but the majority of small cholesteatoma were not detected.

CONCLUSIONS

MRI is a key examen to diagnosed the residual cholesteatoma but is limited by the size of the lesion under 3mm. Delaying the realization of MRI during follow-up could increase sensitivity, thus avoiding misdiagnosis as well as unnecessary second look surgery.

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.

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.

Comparison of accuracy of intravoxel incoherent motion and apparent diffusion coefficient techniques for predicting malignancy of head and neck tumors using half-Fourier single-shot turbo spin-echo diffusion-weighted imaging

PURPOSE

To evaluate the use of the intravoxel incoherent motion (IVIM) technique in half-Fourier single-shot turbo spin-echo (HASTE) diffusion-weighted imaging (DWI), and to compare its accuracy to that of apparent diffusion coefficient (ADC) to predict malignancy in head and neck tumors.

PATIENTS AND METHODS

HASTE DW images of 33 patients with head and neck tumors (10 benign and 23 malignant) were evaluated. Using the IVIM technique, parameters (D, true diffusion coefficient; f, perfusion fraction; D*, pseudodiffusion coefficient) were calculated for each tumor. ADC values were measured over a range of b values from 0 to 1000s/mm(2). IVIM parameters and ADC values in benign and malignant tumors were compared using Student's t test, receiver operating characteristics (ROC) analysis, and multivariate logistic regression modeling.

RESULTS

Mean ADC and D values of malignant tumors were significantly lower than those of benign tumors (P<0.05). Mean D* values of malignant tumors were significantly higher than those of benign tumors (P<0.05). There was no significant difference in mean f values between malignant and benign tumors (P>0.05). The technique of combining D and D* was the best for predicting malignancy; accuracy for this model was higher than that for ADC.

CONCLUSIONS

The IVIM technique may be applied in HASTE DWI as a diagnostic tool to predict malignancy in head and neck masses. The use of D and D* in combination increases the diagnostic accuracy in comparison with ADC.

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.

Does diffusion-weighted MRI (DW-MRI) change treatment strategy in pediatric cholesteatoma?

CONCLUSION

This review highlights the currently limited and contradictory evidence on the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the management of pediatric cholesteatoma patients. Available data confirm the need for prospective DW-MRI studies of a larger number of pediatric patients. Factors such as patient compliance, adhesion to follow-up or local logistic circumstances should also be considered.

OBJECTIVES

This systematic review aimed to collect and analyze the body of evidence on the usefulness of DW-MRI in first-stage tympanoplasty and in replacing second-look surgery in children with cholesteatoma.

METHODS

A comprehensive search of medical databases was conducted. The keywords used were pediatric/paediatric, magnetic resonance imaging, MRI, DW-MRI, cholesteatoma, child, and all meaningful combinations of them.

RESULTS

Only one study with 17 patients primarily fulfilled all criteria. Sensitivity, specificity, and positive and negative predictive values were 62%, 88%, 89%, and 58%, respectively. A second study retrospectively analyzed a subset of younger patients (n = 21) of a larger population. Sensitivity, specificity, and positive and negative predictive values were 100%. One additional study described 1 child and 11 adolescents among 32 cases. In all cases the correlation between imaging and surgery findings was 100%. There were no randomized controlled trials and power calculations were not performed.

MRI for the diagnosis of recurrent middle ear cholesteatoma in children--can we optimize the technique? Preliminary study

BACKGROUND

Recurrent cholesteatoma after surgical excision occurs frequently in children. Until recently, a surgical second look was mandatory and considered as standard reference. MRI including a delayed T1 sequence after gadolinium injection and diffusion-weighted imaging (DWI) has proved its efficiency but has been evaluated mainly in adults.

OBJECTIVE

Our purpose was to evaluate the accuracy of DWI to diagnose recurrence of cholesteatoma in children.

MATERIALS AND METHODS

We evaluated prospectively with MRI 20 ears in 18 children who had had surgery for cholesteatoma. We compared DWI and delayed T1-weighted images following gadolinium administration with intraoperative or follow-up findings. We calculated the sensitivity and specificity of each sequence for the diagnosis of recurrent cholesteatoma.

RESULTS

Sensitivity to diagnose recurrent cholesteatoma was 87% for both DWI and delayed post-gadolinium sequences, specificity was 71% and 83%, respectively. Adding both sequences, the sensitivity was 87%, the specificity 100%. There was one false negative probably due to small size recurrence.

CONCLUSION

In our series, DWI was reliable to diagnose recurrent cholesteatoma in children and allows avoiding surgery when negative. However, because small recurrences less than 5 mm may be missed, follow-up must be prolonged (5 years).

Contemporary non-echo-planar diffusion-weighted imaging of middle ear cholesteatomas

Middle ear cholesteatoma is a common inflammatory disease that requires surgery due to potentially serious intracranial complications. Diagnosis of cholesteatoma is mainly clinical, with computed tomography (CT) used to evaluate disease extension before surgery. Certain patterns of bone erosion are specific, but CT attenuation does not allow differentiation from other inflammatory middle ear diseases. With its high tissue discrimination and contrast resolution, magnetic resonance imaging is valuable in diagnosis of cholesteatomas. Absent enhancement at delayed postcontrast imaging has been used for diagnosis. Diffusion-weighted imaging (DWI) is highly specific due to the high keratin content of cholesteatomas. New non-echo-planar DWI sequences, such as periodically rotated overlapping parallel lines with enhanced reconstruction, are superior to conventional echo-planar DWI, since they minimize susceptibility artifacts at the skull base and increase sensitivity for detection of lesions as small as 2 mm. This technique is indicated when clinical diagnosis is difficult and high tissue specificity is necessary, as in congenital, temporal bone, or atypical acquired middle ear cholesteatomas and residual or recurrent disease after surgery. Non-echo-planar DWI has been proposed for screening of postsurgical (residual or recurrent) cholesteatomas, thus obviating many second-look revision surgeries, especially after more conservative canal wall up surgery.

A systematic review of diffusion-weighted magnetic resonance imaging in the assessment of postoperative cholesteatoma

OBJECTIVE

A systematic review to determine whether the diffusion-weighted (DW) magnetic resonance imaging scan can reliably detect residual or recurrent cholesteatoma after mastoid surgery.

DESIGN

A systematic review.

DATA SOURCES

Databases including EMBASE, MEDLINE, CINAHL, Web of Science, and Cochrane Review were searched for studies published without language restriction from the start of the databases. Additional studies were identified from cited references.

SELECTION CRITERIA

Initial search identified 402 publications, of which 16 studies met the inclusion criteria for the systematic review. The DW imaging (DWI) scan was used to detect residual or recurrent cholesteatoma and subsequent second-look surgery was performed to correlate the findings.

REVIEW METHODS

Studies were assessed for their selection of patients for radiologic investigations, imaging parameters, and subsequent surgery. Outcome measures included sensitivity, specificity, positive and negative predictive values of the DWI, and the incidence and size of residual or recurrent cholesteatoma.

RESULTS

Two different modalities of DWI sequences have been described. Eight studies with 225 patients analyzed echo-planar imaging (EPI) and 8 studies with 207 patients described the "non-EPI" scanning techniques. Non-EPI parameters are more reliable in identifying residual or recurrent cholesteatoma with sensitivity, specificity, and positive and negative predictive values of 91%, 96%, 97%, and 85%, respectively.

CONCLUSION

The available evidence suggests that non-EPI such as half-Fourier acquisition single-shot turbo spin echo sequences are more reliable in identifying residual or recurrent cholesteatoma. This is a promising radiologic investigation; however, we think further studies are required with more patients and long-term results to establish its place as an alternative to a second-stage surgery after canal wall up surgery.

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

OBJECTIVE

To evaluate the diagnostic performance of half-Fourier-acquisition single-shot turbo-spin-echo (HASTE) diffusion-weighted magnetic resonance imaging in the detection, localisation and prediction of extent of cholesteatoma following canal wall up mastoid surgery.

STUDY DESIGN

Prospective blinded observational study.

SETTING

University affiliated teaching hospital.

PATIENTS

Forty-eight patients undergoing second-look surgery after previous canal wall up mastoid surgery for primary acquired cholesteatoma.

INTERVENTIONS

All patients underwent non-echo planar HASTE diffusion-weighted imaging prior to being offered 'second-look' surgery.

MAIN OUTCOME MEASURES

Radiological findings were correlated with second-look intra-operative findings in 38 cases with regard to presence, location and maximum dimensions of cholesteatoma.

RESULTS

Half-Fourier-acquisition single-shot turbo-spin-echo diffusion-weighted imaging accurately predicted the presence of cholesteatoma in 23 of 28 cases, and it correctly excluded in nine of 10 cases. Five false negatives were caused by keratin pearls of <2 mm and in one case 5 mm. Overall sensitivity and specificity for detection of cholesteatoma were 82% (95% confidence interval [CI] 62-94%) and 90% (CI 55-100%), respectively. Positive predictive value and negative predictive value were 96% (CI 79-100%) and 64% (CI 35-87%), respectively. Overall accuracy for detection of cholesteatoma was 84% (CI 69-94%). Half-Fourier-acquisition single-shot turbo-spin-echo diffusion-weighted imaging has good performance in localising cholesteatoma to a number of anatomical sub-sites within the middle ear and mastoid (sensitivity ranging from 75% to 88% and specificity ranging from 94% to 100%). There was no statistically significant difference in the size of cholesteatoma detected radiologically and that found during surgery (paired t-test, P = 0.16). However, analysis of size agreement suggests possible radiological underestimation of size when using HASTE diffusion-weighted imaging (mean difference -0.6 mm, CI -5.3 to 4.6 mm).

CONCLUSION

Half-Fourier-acquisition single-shot turbo-spin-echo diffusion-weighted imaging performs reasonably well in predicting the presence and location of postoperative cholesteatoma but may miss small foci of disease and may underestimate the true size of cholesteatoma.

The diagnostic accuracy of non-echo-planar diffusion-weighted imaging in the detection of residual and/or recurrent cholesteatoma of the temporal bone

BACKGROUND AND PURPOSE

Non-EPI DWI is a promising alternative to second-look surgery for the detection of residual and/or recurrent cholesteatoma. We evaluated the diagnostic accuracy, expressed as a positive predictive value, of MR imaging for the detection of residual and/or recurrent cholesteatoma in our hospital.

MATERIALS AND METHODS

Fifty-six MR imaging studies were performed from 2005 to 2010 in patients having previously undergone surgery for cholesteatoma. Pre- and postgadolinium T1-weighted, T2-weighted, and non-EPI DWI sequences were performed and correlated with clinical and intraoperative findings. Twenty-seven patients underwent second-look surgery; 7 were under close clinical follow-up. Twenty-two patients without evidence of cholesteatoma were under regular follow-up (range, 14-44 months).

RESULTS

Non-EPI DWI sequences showed increased DW signal intensity in 36 patients. Of those, 27 had second-look surgery, confirming cholesteatoma in 25 patients; in 1 patient, an empyema was diagnosed, and in the other patient, no cholesteatoma was found at surgery. In 2 patients who had not undergone surgery, increased DW signal intensity was accompanied by hyperintense signal intensity on T1-weighted images, consistent with transplanted fat in the postoperative cavity. The positive predictive value for detection of cholesteatoma was 93% (25/27).

CONCLUSIONS

Residual and/or recurrent cholesteatomas after primary cholesteatoma surgery can be accurately detected by increased DW signal intensity on non-EPI DWI. However, DWI without conventional sequences increased the risk of misdiagnosis in our patient setting because transplanted fat within the postoperative cavity may show increased DW signal intensity.

Predictive validity of MRI in detecting and following cholesteatoma

High recurrence rate of the middle ear cholesteatoma requires regular postoperative follow-up. This study evaluated data from the patients investigated with DW MRI to ascertain (1) the strength of the technique in detecting primary, and residual recurrent cholesteatoma, and (2) its accuracy in differentiating cholesteatoma from postoperative tissue changes. The diagnostic accuracy of two different DW imaging (EPI and non-EPI) techniques was evaluated. The data have been collected prospectively from 33 consecutive patients with either primary cholesteatoma, or with suspicious symptoms for potential cholesteatoma recurrence. The findings from non-EPI (HASTE) DW MR and EPI DW MR images were blindly compared with those obtained during a primary or secondary surgery. Preoperative non-EPI (HASTE) DWI pointed to a cholesteatoma in 25 out of 33 patients. In this subgroup, cholesteatoma were confirmed also by the surgery. In five cases, the non-EPI (HASTE) DWI did not show a cholesteatoma in the temporal bone, which agreed with the surgical findings. Three misclassifications were made by non-EPI (HASTE) DWI, all in the subgroup of patients indicated for primary surgery. The resulting pooled sensitivity of non-EPI (HASTE) DW imaging for diagnosing cholesteatoma in our study amounted to 96.15% (95% confidence interval (CI) 80.36-99.9), specificity was 71.43% (95% CI 29.04-96.33). Positive predictive value was 92.59% (95% CI 75.71-99.09) and negative predictive value 83.33% (95% CI 35.88-99.58). In conclusion, we recommend the non-EPI (HASTE) DW MRI as a valid method for diagnosing cholesteatoma and follow-up after cholesteatoma surgery.

Imaging of postoperative middle ear cholesteatoma

Cholesteatoma is often treated surgically using canal wall-preserving techniques. Clinical and otoscopic diagnosis of residual or recurrent disease after this form of surgery is unreliable and thus radiological imaging is often used prior to mandatory "second-look" surgery. Imaging needs to be able to differentiate residual or recurrent disease from granulation tissue, inflammatory tissue or fluid within the middle ear cavity and mastoid cavity. High-resolution computed tomography (HRCT), conventional magnetic resonance imaging (MRI), and delayed contrast MRI have all been used in detecting postoperative cholesteatoma. Although delayed contrast MRI performs better than HRCT and conventional MRI, the sensitivities and specificities of these different imaging methods are relatively poor. Diffusion-weighted MRI (DWI and, in particular, non-echo planar DWI) has been shown to have a high sensitivity and specificity for detecting recurrent cholesteatoma. In this review we provide examples of postoperative imaging appearances following cholesteatoma surgery and we review the relevant literature with an emphasis on studies evaluating the diagnostic accuracy of DWI.

Diffusion-weighted magnetic resonance imaging of the temporal bone

This paper summarizes the value of diffusion-weighted magnetic resonance imaging in the evaluation of temporal bone pathology. It highlights the use of different types of diffusion-weighted magnetic resonance imaging in the different types of cholesteatoma, prior to first stage surgery and prior to second look surgery. The value of diffusion-weighted magnetic resonance imaging in the evaluation of pathology of the apex of the petrous bone and the cerebellopontine angle is also discussed.