Diffusion-weighted MRI of cholesteatomas of the petrous bone

Diffusion Analysis of Intracranial Epidermoid, Head and Neck Epidermal Inclusion Cyst, and Temporal Bone Cholesteatoma

BACKGROUND AND PURPOSE

Intracranial epidermoids temporal bone cholesteatomas, and head and neck epidermal inclusion cysts are typically slow-growing, benign conditions arising from ectodermal tissue. They exhibit increased signal on DWI. While much of the imaging literature describes these lesions as showing diffusion restriction, we investigated these qualitative signal intensities and interpretations of restricted diffusion with respect to normal brain structures. This study aimed to quantitatively evaluate the ADC values and histogram features of these lesions.

MATERIALS AND METHODS

This retrospective study included children with histologically confirmed diagnoses of intracranial epidermoids, temporal bone cholesteatomas, or head and neck epidermal inclusion cysts. Lesions were segmented, and voxelwise calculation of ADC values was performed along with histogram analysis. ADC calculations were validated with a second analysis software to ensure accuracy. Normal brain ROIs-including the cerebellum, white matter, and thalamus-served as normal comparators. Correlational analysis and Bland-Altman plots assessed agreement among software tools for ADC calculations. Differences in the distribution of values between the lesions and normal brain tissues were assessed using the Wilcoxon rank sum and Kruskal-Wallis tests.

RESULTS

Forty-eight pathology-proved cases were included in this study. Among them, 13 (27.1%) patients had intracranial epidermoids 14 (29.2%) had head and neck epidermal inclusion cysts, and 21 (43.7%) had temporal bone cholesteatomas. The mean age was 8.67 (SD, 5.30) years, and 27 (56.3%) were female. The intraclass correlation for absolute agreement for lesional ADC between the 2 software tools was 0.997 (95% CI, 0.995-0.998). The intracranial epidermoid head and neck epidermal inclusion cyst, and temporal bone cholesteatoma median ADC values were not significantly different (973.7 versus 875.7 versus 933.2 × 10-6 mm2/s, P = .265). However, the ADCs of the 3 types of lesions were higher than those of 3 normal brain tissue types (933 versus 766, × 10-6 mm2/s, P < .001).

CONCLUSIONS

The ADC values of intracranial epidermoids, temporal bone cholesteatomas, and head and neck epidermal inclusion cysts are higher than those of normal brain regions. It is not accurate to simply classify these lesions as exhibiting restricted diffusion or reduced diffusivity without considering the tissue used for comparison. The observed hyperintensity on DWI compared with the brain is likely attributable to a relatively higher contribution of the T2 shinethrough effect.

Beyond the otoscope: an imaging review of congenital cholesteatoma

Congenital cholesteatoma (CC) is a non-neoplastic lesion of keratin debris lined by epithelium found in the temporal bone. It is the lesser-known sibling of the acquired cholesteatoma and may be classified as congenital middle ear cholesteatoma and congenital petrous bone cholesteatoma. The incidence is rising, probably owing to increased recognition and advances in imaging modalities. Cone beam CT provides detailed anatomical information, highlighting quadrant location, ossicular involvement, and mastoid extension. MRI aids in lesion characterization and detection of complications. The classification systems for congenital middle ear and petrous bone cholesteatoma are helpful in the preoperative workup and have a role in predicting postoperative recurrence rates. Management almost invariably involves surgical intervention aimed at preserving middle and inner ear function. Follow-up of CC is mainly based on MRI together with otoscopic examination. Non-echo planar diffusion-weighted imaging, especially, has proven essential for detecting residual disease. This review article emphasizes the significance of imaging in the timely diagnosis and management of CCs. CLINICAL RELEVANCE STATEMENT: This article underscores the crucial role of imaging for prompt detection, preoperative assessment, and postoperative follow-up of CCs, a condition with rising incidence associated with potentially severe complications. KEY POINTS: Timely diagnosis of CCs is imperative for avoiding complications. Imaging is key in detection, preoperative evaluation, and postoperative management. Cone Beam CT and non-echo planar DWI represent state-of-the-art imaging techniques.

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.

Endoscopic Transsphenoidal Drainage of Petrous Apex Mucocele

Approaching the petrous apex can be complex and fraught with danger. Identifying favorable pathology and gaining access endoscopically is a direct, fast, and minimally invasive. Supported by navigation, it can be safely used in the vicinity of vital structures. A mucocele requires creation of a wide drainage pathway and can be an ideal lesion for such an approach.

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.

Comparison of Readout-Segmented Echo-Planar Imaging and Single-Shot TSE DWI for Cholesteatoma Diagnostics

BACKGROUND AND PURPOSE

The high diagnostic value of DWI for cholesteatoma diagnostics is undisputed. This study compares the diagnostic value of readout-segmented echo-planar DWI and single-shot TSE DWI for cholesteatoma diagnostics.

MATERIALS AND METHODS

Thirty patients with newly suspected cholesteatoma were examined with a dedicated protocol, including readout-segmented echo-planar DWI and single-shot TSE DWI at 1.5T. Acquisition parameters of both diffusion-weighted sequences were as follows: b=1000 s/mm,² axial and coronal section orientations, and section thickness of 3 mm. Image quality was evaluated by 2 readers on a 5-point Likert scale with respect to lesion conspicuity, the presence of susceptibility artifacts mimicking cholesteatomas, and overall subjective image quality. Sensitivity and specificity were calculated using histology results as the gold standard.

RESULTS

Twenty-five cases of histologically confirmed cholesteatomas were included in the study group. Lesion conspicuity was higher and fewer artifacts were found when using TSE DWI (both P < .001). The overall subjective image quality, however, was better with readout-segmented DWI. For TSE DWI, the sensitivity for readers 1 and 2 was 92% (95% CI, 74%-99%) and 88% (95% CI, 69%-97%), respectively, while the specificity for both readers was 80% (95% CI, 28%-99%). For readout-segmented DWI, the sensitivity for readers 1 and 2 was 76% (95% CI, 55%-91%) and 68% (95% CI, 46%-85%), while the specificity for both readers was 60% (95% CI, 15%-95%).

CONCLUSIONS

The use of TSE DWI is advisable for cholesteatoma diagnostics and preferable over readout-segmented DWI.

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.

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.

The Role of Non-Echoplanar Diffusion-Weighted Magnetic Resonance Imaging in Diagnosis of Primary Cholesteatoma and Cholesteatoma Recidivism as an Adjunct to Clinical Evaluation

Introduction:

The aim of this study was to analyze the sensitivity and specificity of non-echoplanar (non-EPI) diffusion-weighted (DW) magnetic resonance imaging (MRI) for the detection of cholesteatoma, with a focus on its value as an adjunct to clinical examination.

Methods:

In a prospective cohort study, 92 cases were divided into 2 groups: “clinically cholesteatoma” ( n = 79) and “clinically no cholesteatoma” ( n = 13). Non-EPI DW MRI was performed preoperatively in all cases. The presence of a cholesteatoma was assessed by clinicians otoscopically, by neuroradiologists on non-EPI DW MRI, by the surgeon intraoperatively, and finally by the pathologist postoperatively. Data analysis was performed for specificity, sensitivity, positive predictive value, negative predictive value, and interrater variability.

Results:

The sensitivity and specificity were 89.3% and 75%, respectively, in the “clinically cholesteatoma” group and 0% and 100% in the “clinically no cholesteatoma” group. Non-EPI DW MRI had a positive predictive value of 98.5% when cholesteatoma was suspected clinically and a negative predictive value of 84.6% when cholesteatoma was not suspected clinically.

Conclusion:

If cholesteatoma is suspected clinically, non-EPI DW MRI is not necessary. If there is no clinical suspicion of cholesteatoma in second-look situations, sensitivity is low and serial follow-up MRI with long intervals is advised.

ADC Benchmark Range for Correct Diagnosis of Primary and Recurrent Middle Ear Cholesteatoma

OBJECTIVES

Magnetic resonance imaging (MRI) and in particular diffusion-weighted imaging (DWI) have been broadly proven to be the reference imaging method to discriminate between cholesteatoma and noncholesteatomatous middle ear lesions, especially when high tissue specificity is required. The aim of this study is to define a range of apparent diffusion coefficient (ADC) values within which the diagnosis of cholesteatoma is almost certain.

METHODS

The study was retrospectively conducted on a cohort of 124 patients. All patients underwent first- or second-look surgery because primary or secondary acquired cholesteatoma was clinically suspected; they all had preoperative MRI examination 15 days before surgery, including DWI from which the ADC maps were calculated.

RESULTS

Average ADC value for cholesteatomas was 859,4 × 10-6 mm2/s (range 1545 × 10-6 mm2/s; IQR = 362 × 10-6 mm2/s; σ = 276,3 × 10-6 mm2/s), while for noncholesteatomatous inflammatory lesions, it was 2216,3 × 10-6 mm2/s (range 1015 × 10-6 mm2/s; IQR = 372,75 × 10-6 mm2/s; σ = 225,6 × 10-6 mm2/s). Interobserver agreement with Fleiss' Kappa statistics was 0,96. No overlap between two groups' range of values was found and the difference was statistically significant for p < 0.0001.

CONCLUSIONS

We propose an interval of ADC values that should represent an appropriate benchmark range for a correct differentiation between cholesteatoma and granulation tissue or fibrosis of noncholesteatomatous inflammatory lesions.

A giant cholesteatoma of the mastoid extending into the foramen magnum: A case report and review of literature

Cholesteatomas are very rare benign, progressive lesions that have embryologic derivation and usually result in progressive exfoliation and confinement of squamous epithelium behind an intact or preciously infected tympanic membrane. To the best of our understanding no reports demonstrates the extension of cholesteatoma from the temporal bone into the foramen magnum. We therefore present a case of cholesteatoma extending down into the foramen magnum. We report a case of 67- year-old man with a giant cholesteatoma extending into the foramen magnum without substantial destruction of the mastoid and petrous temporal bones. The patient’s major symptoms were recurrent tinnitus in the left ear and dizziness with unilateral conductive hearing loss. A working diagnosis of cholesteatomas was made combining the symptoms and magnetic resonance imaging findings. He was then successfully operated on with very minimal postoperative complications. Cholesteatomas originating from the mastoid bone often linger with the patients for many years in a subclinical state and progress into a massive size before causing symptoms. Patients with unilateral conductive hearing loss who are otherwise asymptomatic and have a normal tympanic membrane should be suspected with a progressive cholesteatoma. Cholesteatoma should be one of the working diagnosis when an elderly patient present with unilateral conductive hearing loss that is associated with tinnitus and dizziness.

Diffusion weighted imaging for the detection and evaluation of cholesteatoma

Cholesteatoma is a collection of keratinous debris and stratified squamous epithelium. It is trapped in the middle ear and can lead to bony erosion. The disease is treated surgically often followed by a second-look procedure to check for residual tissue or recurrence. Cholesteatoma has specific signal-intensity characteristics on magnetic resonance imaging with very high signal intensity on diffusion weighted imaging (DWI). Various DWI techniques exist: Echo-planar imaging (EPI)-based and non-EPI-based techniques as well as new approaches like multi-shot EPI DWI. This article summarizes all techniques, discusses the significance in detecting cholesteatoma and mentions actual studies. Further recommendations for daily clinical practise are provided.

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.

The value of non echo planar, diffusion-weighted magnetic resonance imaging for the detection of residual or recurrent middle-ear cholesteatoma

Objective:

To determine the value of non echo planar, diffusion-weighted magnetic resonance imaging for detection of residual and recurrent middle-ear cholesteatoma after combined-approach tympanoplasty.

Method:

The magnetic resonance imaging findings after primary surgery for cholesteatoma were compared with intra-operative findings at ‘second-look’ surgery or with clinical follow-up findings.

Results:

Forty-eight magnetic resonance imaging studies were performed in 38 patients. Second-look surgery was performed 21 times in 18 patients. The remaining patients were followed up at the out-patient clinic. There were no false-positive findings with non echo planar, diffusion-weighted magnetic resonance imaging; however, there were four false-negative findings. The mean maximum diameter of recurrent cholesteatoma, as assessed using magnetic resonance imaging, was 11.7 mm (range, 4.4–25.3 mm). The sensitivity of non echo planar, diffusion-weighted magnetic resonance imaging for detecting cholesteatoma prior to second-look surgery was 0.76, with a specificity of 1.00. When clinical follow up of the non-operated ears was included in the analysis, sensitivity was 0.81 and specificity was 1.00.

Conclusion:

Recurrent cholesteatoma can be accurately detected using non echo planar, diffusion-weighted magnetic resonance imaging. Our study, however, also showed some false-negative results. Therefore, strict out-patient follow up is mandatory for those considering using this technique instead of standard second-look surgery.

High-resolution three-dimensional diffusion-weighted imaging of middle ear cholesteatoma at 3.0 T MRI: usefulness of 3D turbo field-echo with diffusion-sensitized driven-equilibrium preparation (TFE-DSDE) compared to single-shot echo-planar imaging

OBJECTIVE

To prospectively evaluate the usefulness of a newly developed high-resolution three-dimensional diffusion-weighted imaging method, turbo field-echo with diffusion-sensitized driven-equilibrium (TFE-DSDE) in diagnosing middle-ear cholesteatoma by comparing it to conventional single-shot echo-planar diffusion-weighted imaging (SS-EP DWI).

MATERIALS AND METHODS

Institutional review board approval and informed consent from all participants were obtained. We studied 30 patients with preoperatively suspected acquired cholesteatoma. Each patient underwent an MR examination including both SS-EP DWI and DSDE-TFE using a 3.0 T MR scanner. Images of the 30 patients (60 temporal bones including 30 with and 30 without cholesteatoma) were reviewed by two independent neuroradiologists. The confidence level for the presence of cholesteatoma was graded on a scale of 0-2 (0=definite absence, 1=equivocal, 2=definite presence). Interobserver agreement as well as sensitivity, specificity, and accuracy for detection were assessed for the two reviewers.

RESULTS

Excellent interobserver agreement was shown for TFE-DSDE (κ=0.821) whereas fair agreement was obtained for SS-EP DWI (κ=0.416). TFE-DSDE was associated with significantly higher sensitivity (83.3%) and accuracy (90.0%) compared to SS-EP DWI (sensitivity=35.0%, accuracy=66.7%; p<0.05). No significant difference was found in specificity (96.7% for TFE-DSDE, 98.3% for SS-EP DWI) CONCLUSION: With increased spatial resolution and reduced susceptibility artifacts, TFE-DSDE improves the accuracy in diagnosing acquired middle ear cholesteatomas compared to SS-EP DWI.

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).

[The use of MRI DWI-imaging in assessment of cholesteatoma recurrences after canal wall up technique]

INTRODUCTION

The use of closed technique in cholesteatoma treatment carries a significant risk of development of residual disease thus requires a second look operation in a proportion of patients. In those with no residual cholesteatoma the second surgery could be avoided.

THE AIM OF THE STUDY

was to evaluate the use of non-echo planar HASTE diffusion-weighted MR imaging in the detection of cholesteatoma in patients after canal wall up surgery due to cholesteatoma.

MATERIAL AND METHODS

We evaluate the results of half-Fourier-acquisition single-shot turbo-spin-echo (HASTE) diffusion-weighted magnetic resonance imaging in 18 patients after canal wall up surgery performed 6 to 20 months after primary surgery. 16 patients were operated in our center and 2 elsewhere. All the patients underwent second look surgery that verified the result of MRI scanning.

RESULTS

MRI DWI detected 2 cholesteatomas in patients operated elsewhere and none in patients operated in our center. Four cholesteatomas were found during second look operations. Two false negatives were in 1 patient with cholesteatoma pearl of less than 2mm in diameter and in 1 patient with mural cholesteatoma. There were no false positive results.

CONCLUSION

Non EPI MRI DWI can be used as a screening tool to detect residual or recurrent cholesteatoma and may substitute the need of second look surgery.

Colesteatoma: utilidade da sequência de difusão sem echo-planar

Colesteatomas são lesões císticas congênitas ou adquiridas que acometem as orelhas e que podem apresentar padrões típicos aos estudos de tomografia computadorizada, em função de suas características expansivas e tendência a promover erosão óssea. Entretanto, particularmente nos casos de resíduo ou recorrência pós-cirúrgica, a distinção entre colesteatoma e tecido inflamatório pode ser bastante difícil e, não raro, impossível com base somente nos achados tomográficos. A avaliação por ressonância magnética pode ser útil, particularmente neste contexto, uma vez que as sequências pós-contraste obtidas tardiamente e a difusão podem demonstrar padrões distintos nestas duas situações. Os artefatos condicionados pela interface ar/osso na região das mastoides podem limitar bastante a utilização da sequência de difusão echo-planar. A sequência de difusão sem echo-planar é uma alternativa na solução deste problema por estar menos sujeita a este tipo de artefato, fornecendo ainda imagens com maior resolução espacial e com espessuras de corte mais finas, as quais permitem a detecção de colesteatomas de pequenas dimensões.

Diffusion-weighted MR imaging in the head and neck

Extracranial applications of diffusion-weighted (DW) magnetic resonance (MR) imaging are gaining increasing importance, including in head and neck radiology. The main indications for performing DW imaging in this relatively small but challenging region of the body are tissue characterization, nodal staging, therapy monitoring, and early detection of treatment failure by differentiating recurrence from posttherapeutic changes. Lower apparent diffusion coefficients (ADCs) have been reported in the head and neck region of adults and children for most malignant lesions, as compared with ADCs of benign lesions. For nodal staging, DW imaging has shown promise in helping detect lymph node metastases, even in small (subcentimeter) nodes with lower ADCs, as compared with normal or reactive nodes. Follow-up of early response to treatment is reflected in an ADC increase in the primary tumor and nodal metastases; whereas nonresponding lesions tend to reveal only a slight increase or even a decrease in ADC during follow-up. Optimization and standardization of DW imaging technical parameters, comparison of DW images with morphologic images, and increasing experience, however, are prerequisites for successful application of this challenging technique in the evaluation of various head and neck pathologic conditions.

Diagnostic accuracy of non-echo-planar diffusion-weighted MRI versus other MRI sequences in cholesteatoma

INTRODUCTION

Non-echo-planar imaging (EPI) MRI has been recently introduced to improve the detection of small-sized cholesteatoma and decrease different artefacts occurring in the EPI-diffusion-weighted (DW) technique. This technique is also time saving in comparison to delayed post-contrast imaging. We prospectively assessed the diagnostic accuracy of MRI including delayed post-contrast standard MRI, EPI and non-EPI-DW sequences in the detection of middle ear cholesteatoma.

METHODS

We evaluated 35 patients suspected of having cholesteatoma who underwent MRI including delayed post-contrast MRI, EPI and non-EPI-DW sequences prior to their planned surgery, and the MR findings were compared with surgical findings. Two experienced radiologists reported the images. Sensitivity, specificity and predictive values of MRI were estimated.

RESULTS

We detected 26 cases of cholesteatoma at surgery. Sensitivity and specificity of delayed post-contrast MRI, EPI DW and non-EPI DW were 73.1 and 77.8%, 61.5 and 88.9%, and 96.2 and 100%, respectively, as interpreted by the first radiologist. Sensitivity and specificity of delayed post-contrast MRI, EPI-DW sequence and non-EPI-DW sequence were 84.6 and 88.9%, 50 and 88.9%, and 92.3 and 100%, respectively, as interpreted by the second radiologist.

CONCLUSION

The non-EPI MRI technique is a more accurate method in detecting middle ear cholesteatoma in comparison to other conventional sequences.

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.

Role of magnetic resonance imaging in cholesteatoma: the Indian experience

The objectives are to evaluate role of magnetic resonance imaging (MRI) in diagnosis of cholesteatoma and correlate imaging findings with intraoperative findings, and to emphasize of role of imaging in the follow-up of postoperative patients for differentiating residual/recurrent cholesteatoma from granulation/inflammatory tissue. In this prospective study, 31 patients were evaluated with a specific MRI protocol and high resolution computed tomography of the temporal bones. These included patients with a strong suspicion of having a cholesteatoma on clinical examination and postoperative cases on clinical follow up. Based on specific MRI findings, presence of cholesteatoma was reported in 17 out of 31 patients. All 31 patients underwent surgery and 19 patients had confirmed intraoperative cholesteatoma. This study shows high sensitivity of a specific sequence based MRI examination in detection of cholesteatoma and in differentiating cholesteatoma from postoperative inflammatory/granulation tissue. To the best of the author's knowledge, this is the first such study performed in the Indian Asian population.

Detection of middle ear cholesteatoma by diffusion-weighted MR imaging: multishot echo-planar imaging compared with single-shot echo-planar imaging

BACKGROUND AND PURPOSE

Previous reports have shown that DWI is useful in detecting cholesteatoma. SS-EPI is the most widely used DWI technique. However, SS-EPI may have susceptibility artifacts due to field inhomogeneity in the imaging of the temporal bone region. Our purpose was to prospectively evaluate the advantage of MS-EPI for the diagnosis of middle ear cholesteatoma by comparing it with SS-EPI.

MATERIALS AND METHODS

We studied 29 patients with preoperatively suspected acquired cholesteatoma. Each patient underwent an MR imaging examination including both SS-EPI and MS-EPI by using a 1.5T MR imaging scanner. Images of the 29 patients (58 temporal bones including 30 with and 28 without cholesteatoma) were reviewed by 2 independent neuroradiologists. The confidence level for the presence of cholesteatoma was graded on a scale of 0-2 (0 = none, 1 = equivocal, 2 = definite). Interobserver agreement as well as sensitivity, specificity, and accuracy were assessed for the 2 readers.

RESULTS

Excellent interobserver agreement was shown for both MS-EPI (κ = 0.856) and SS-EPI (κ = 0.820). MS-EPI was associated with higher sensitivity (76.7%) and accuracy (87.9%) than SS-EPI (sensitivity = 50.0%, accuracy = 74.1%) (P < .05), while both methods showed 100% specificity.

CONCLUSIONS

Compared with SS-EPI, MS-EPI improves the accuracy of the diagnosis of acquired middle ear cholesteatomas.

CT and MRI Correlations in Patients with Suspected Cholesteatoma after Surgery

The study of postoperative ear cavities in patients who underwent surgery for cholesteatoma is a difficult challenge for radiologists. In our study we make a correlation between CT and MRI findings, useful tools in patients with suspected residual or recurrent cholesteatoma. The use of different MRI sequences especially DWI can help radiologists to discriminate between cholesteatoma and other different processes.

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.

The utility of diffusion-weighted imaging for cholesteatoma evaluation

DWI is a useful technique for the evaluation of cholesteatomas. It can be used to detect them when the physical examination is difficult and CT findings are equivocal, and it is especially useful in the evaluation of recurrent cholesteatoma. Initial DWI techniques only detected larger cholesteatomas, >5 mm, due to limitations of section thickness and prominent skull base artifacts. Newer techniques allow detection of smaller lesions and may be sufficient to replace second-look surgery in patients with prior cholesteatoma resection.

Neuroradiology of cholesteatomas

The relevant aspects of cholesteatomas are reviewed with the emphasis on their diagnosis by using cross-sectional imaging. The indications and limitations of CT and MR imaging and the use of novel MR imaging techniques in the diagnosis of cholesteatomas are described. HRCT of the temporal bone has an excellent spatial resolution, thus even small soft-tissue lesions can be accurately delineated (high sensitivity). However, CT has poor specificity (ie, soft-tissue structures cannot be differentiated). MR imaging with the conventional sequences (T1WI, T2WI, postcontrast T1WI) provides additional information for distinguishing different pathologic entities and for accurately diagnosing primary (nonsurgical) and residual/recurrent (surgical) cholesteatomas. Higher diagnostic specificity is achieved by introducing DW-EPI, delayed postcontrast imaging, DW-non-EPI, and DWI-PROPELLER techniques. Studies using DW-non-EPI and DWI-PROPELLER sequences show promising results related to improved diagnostic sensitivity and specificity for even small (<5 mm) cholesteatomas, thus allowing avoidance of second-look surgery in the future.

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

OBJECTIVE

Diffusion-weighted (DW) MRI imaging is evolving into an alternative to second look surgery in detection of cholesteatoma recurrence. Insights into the DW MRI appearances of postoperative or inflammatory mucosal changes have recently described using non-echo-planar, turbo spin-echo (TSE) DW MRI which reliably distinguishes between postoperative changes and cholesteatoma. We investigated the use of TSE DW MRI in our pediatric population in order to validate a rapid and cost-effective MRI sequence that can be used to screen for cholesteatoma.

METHODS

Prospective comparative study with adult and pediatric patients at a tertiary referral centre. Patients in the study underwent TSE DW MRI prior to second look or revision surgery for cholesteatoma. A Siemens 1.5 T scanner was employed, using the HASTE sequence (EPI DW MRI) as well as standard echo-planar DWI, T1 and T2 sequences. The MRI findings were then correlated with the intraoperative findings at surgery 9-15 months after primary surgery, or of revision surgery in the cases that were referred from other centres. Detection and localisation of cholesteatoma on TSE DW MRI were compared with the findings at second surgery, long considered the gold standard for detection of residual or recurrent disease. Scanning time between the TSE sequence and the standard planar DW MR were also compared.

RESULTS

In a cohort of 92 patients, 21 pediatric patients were identified. 15 patients have had their 15 second look or revision procedures and DW MRI prior to their surgery. TSE DW MRI detected cholesteatoma and reliably identified the location of the cholesteatoma in 2 patients whom all had disease confirmed at surgery. The 13 cases with negative preoperative DW MRI for cholesteatoma were all confirmed to be disease free at surgery. Scanning time of the TSE sequence takes 100 s as opposed to 20 min using standard echo-planar DW MRI techniques without the requirement of a contrast agent and without the need for a general anaesthetic for any of the children.

CONCLUSION

TSE (HASTE) DW MRI is emerging as a cost effective, noninvasive alternative to second look surgery for detection and screening for cholesteatoma in pediatric patients.

Imaging of inflammatory and infectious diseases in the temporal bone

Inflammatory and infectious diseases of the temporal bone are a major indication to perform high-resolution CT and MR imaging studies. Such studies allow one to evaluate the extent of the disease in the soft tissues and in the bony structures of the temporal bone. On these same imaging studies the possible extension of the infection to surrounding regions is visualized. In this article a segmental approach is used, focusing on four structures in the temporal bone: the external ear, the otomastoid and petrous apex, the inner ear, and the facial nerve. For each of the four sections imaging findings are described and illustrated, and if relevant a differential diagnostic approach is highlighted.

Diffusion-weighted magnetic resonance imaging: its uses in otolaryngology

Over recent years, there has been an increase in otolaryngology publications concerning diffusion-weighted magnetic resonance imaging. The aims of this review paper are to summarise the basic principles of diffusion-weighted magnetic resonance imaging, and to provide an overview of current otolaryngological applications and areas of research. Diffusion-weighted magnetic resonance imaging is a radiological technique which has shown promising results in various areas of otolaryngology. However, studies of diffusion-weighted magnetic resonance imaging are difficult to compare, as different imaging parameters and techniques have been used. The role of this imaging modality within otolaryngology is yet to be fully elucidated. Diffusion-weighted magnetic resonance imaging may prove to be a useful adjunct in both the pre- and post-operative care of otolaryngology patients.

Diffusion-weighted magnetic resonance imaging in the management of cholesteatoma

Diffusion-weighted (DW) MRI has recently increasingly gained popularity in the diagnosis of post-operative cholesteatoma. The aim of this study is to prospectively evaluate the usefulness of echo-planar imaging (EPI) for the diagnosis of residual cholesteatoma. Fifty patients underwent DW-EPI before surgery. Fifteen patients had a scan before their first surgery and 35 patients underwent neuroimaging prior to their second look surgery. In the first preoperative group of 15 patients, DW-EPI confirmed cholesteatoma in all the patients. In the post-operative group DW-EPI identified or excluded cholesteatoma correctly in 29 out of 35 patients. Our study has demonstrated a sensitivity of 83% and specificity of 82% of DW-EPI for the diagnosis of residual cholesteatoma. DW-EPI can be a value imaging modality and may help the surgeon in selecting patients for revision surgery.

Diffusion-weighted MR imaging in postoperative follow-up: reliability for detection of recurrent cholesteatoma

INTRODUCTION

Cholesteatoma is a progressively growing process that destroy the neighboring bony structures and treatment is surgical removal. Follow-up is important in the postoperative period, since further surgery is necessary if recurrence is present, but not if granulation tissue is detected. This study evaluates if diffusion-weighted MR imaging alone can be a reliable alternative to CT, without use of contrast agent for follow-up of postoperative patients in detecting recurrent cholesteatoma.

MATERIALS AND METHODS

26 consecutive patients with mastoidectomy reporting for routine follow-up CT after mastoidectomy were included in the study, if there was loss of middle ear aeration on CT examination. MR images were evaluated for loss of aeration and signal intensity changes on diffusion-weighted sequences. Surgical results were compared with imaging findings.

RESULTS

Interpretation of MR images were parallel with the loss of aeration detected on CT for all 26 patients. Of the 26 patients examined, 14 were not evaluated as recurrent cholesteatoma and verified with surgery (NPV: 100%). Twelve patients were diagnosed as recurrent cholesteatoma and 11 were surgically diagnosed as recurrent cholesteatoma (PPV: 91.7%). Four of these 11 patients had loss of aeration size greater than the high signal intensity area on DWI, which were surgically confirmed as granulation tissue or fibrosis accompanying recurrent cholesteatoma.

CONCLUSION

Diffusion-weighted MR for suspected recurrent cholesteatoma is a valuable tool to cut costs and prevent unnecessary second-look surgeries. It has the potential to become the MR sequence of choice to differentiate recurrent cholesteatoma from other causes of loss of aeration in patients with mastoidectomy.

Postoperative non-echo-planar diffusion-weighted magnetic resonance imaging changes after cholesteatoma surgery: implications for cholesteatoma screening

OBJECTIVES

Diffusion-weighted (DW) magnetic resonance imaging (MRI) is emerging as an alternative to second-look surgery in ruling out residual or recurrent disease after cholesteatoma eradication. However, the DW MRI appearances of postoperative or inflammatory mucosal changes have not been well investigated, thus rendering the interpretation of postoperative DW MRI difficult in the presence of mucosal reactions. We investigated the turbo-spin echo (TSE) DW MRI changes of the middle ear and mastoid mucosa after cholesteatoma surgery and compared these with the TSE DW MRI features of cholesteatoma with an aim to identify a rapid and cost-effective purely DW MRI sequence that can be used to screen for cholesteatoma.

STUDY DESIGN

A prospective comparative study.

SETTING

A tertiary referral center in Western Australia.

PATIENTS

Patients undergoing revision or second-look cholesteatoma surgery.

INTERVENTION

Patients underwent 3 to 6 monthly half-Fourier-acquisition single-shot turbo-spin-echo TSE DW MRI before their second surgery. The MRI findings were then correlated with the intraoperative findings at second-look surgery 6 to 17 months after primary surgery or of revision surgery in the cases that were referred from other centers.

MAIN OUTCOME MEASURE

Detection of cholesteatoma and noncholesteatoma mucosal changes on TSE DW MRI, compared with the gold standard of findings at second surgery.

RESULTS

Twenty-two patients underwent 23 second-look or revision procedures. All patients had DW MRI before their "second-look" or revision surgery. TSE DW MRI detected cholesteatomas in 7 patients whom all had disease confirmed at second-look or revision surgery. In 16 cases shown to be negative on DW MRI for cholesteatoma, all were confirmed to be disease-free on second-look surgery. Cholesteatomas were shown to produce a TSE DW MRI signal clearly distinct from the spectrum of imaging findings encountered in postoperative mucosal changes.

CONCLUSION

TSE DW MRI holds great promise in screening for cholesteatoma as an alternative to exploratory second-look surgery.

3T MR imaging of postoperative recurrent middle ear cholesteatomas: value of periodically rotated overlapping parallel lines with enhanced reconstruction diffusion-weighted MR imaging

BACKGROUND AND PURPOSE

MR diagnostic of postoperative recurrent cholesteatomas is difficult. Our purpose was to compare multishot fast spin-echo periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted MR imaging (DWI) with array spatial sensitivity encoding technique (ASSET) single-shot echo-planar DWI and late postgadolinium T1-weighted MR imaging for the detection of postoperative recurrent middle ear cholesteatomas with a 3T imaging unit.

MATERIALS AND METHODS

Thirty-five patients with suggested postoperative recurrent middle ear cholesteatoma underwent 3T MR imaging with PROPELLER DWI, ASSET echo-planar DWI, and late postgadolinium T1-weighted MR imaging. Three radiologists (2 seniors, 1 fellow) analyzed unlabeled images for visualization of recurrence. Interobserver and intraobserver agreement was assessed by using the Cohen kappa statistic test. Sensitivity, specificity, and predictive value were assessed for the 3 observers.

RESULTS

Nineteen recurrent cholesteatomas were diagnosed. PROPELLER interobserver agreement was very good (1, 0.89, 0.89) among the 3 observers. Intraobserver agreement between PROPELLER and T1-weighted imaging was very good to moderate (0.88, 0.57, 0.58). PROPELLER DWI provided less interobserver variability than other sequences, and the best sensitivity, specificity, and predictive value.

CONCLUSIONS

On a 3T imaging unit, multishot fast spin-echo PROPELLER DWI allows an easier detection of postoperative recurrent middle ear cholesteatoma than T1-weighted imaging by reducing artifacts and by its better contrast. DWI with PROPELLER is diagnostically robust and accurate.

The role of magnetic resonance imaging in the postoperative management of cholesteatomas

Conventional CT and MRI scans have low specificity when it comes to differentiating granulation tissue from relapsing cholesteatoma.

Aim

this paper aims to analyze the use of DWI and delayed post-contrast T1-weighed imaging in the detection of recurring cholesteatomas.

Materials and method

this is a cross-sectional prospective study that looked at 17 cholesteatoma patients postoperatively. All patients underwent diffusion magnetic resonance imaging at 1.5T, T1, T2, and delayed post-contrast T1 and images were produced from both coronal and axial planes. Two radiologists assessed the images and decided consensually that the presence of hyperintensive signal in DWI on T2, iso/ hypointensive signal on T1, and absence of contrast uptake were indicative of relapsing cholesteatoma. Surgical review findings were compared to DWI scans.

Results

eleven of the twelve cases of recurring cholesteatoma presented hyperintensive signal in the DWI scans. None of the patients with granulation tissue in the surgical wound presented hyperintensive signal in the DWI scans. A patient with an abscess in the internal acoustic meatus also presented a hyperintensive signal in the DWI scans. Sensibility, specificity, positive predictive value and negative predictive value were 91.6%, 60.0%, 84.6%, and 75.0%, respectively.

Conclusion

DWI combined with delayed post-contrast T1 SE sequence proved to be useful in the differential diagnosis of granulation tissue and recurring cholesteatoma.

Detection of postoperative residual cholesteatoma with non-echo-planar diffusion-weighted magnetic resonance imaging

OBJECTIVE

The aim of this study was to analyze the role of non-echo-planar imaging (non-EPI)-based diffusion-weighted (DW) magnetic resonance imaging (MRI) for the detection of residual cholesteatoma after canal wall-up mastoidectomy before eventual second-look surgery.

STUDY DESIGN

Prospective and blinded study.

SETTING

Tertiary referral center.

PATIENTS

The study group included the surgical, clinical, and imaging follow-up of 32 consecutive patients after primary cholesteatoma surgery.

INTERVENTIONS

All patients were investigated with MRI, including late postgadolinium T1-weighted sequence and non-EPI-DW sequence, 10 to 18 months after first-stage cholesteatoma surgery by experienced surgeons using a canal wall-up mastoidectomy. The non-EPI-DW images were evaluated for the presence of a high-signal intensity lesion consistent with residual cholesteatoma. Imaging findings were correlated with findings from second-stage surgery in 19 patients, clinical follow-up examination in 11 patients, and, in 2 patients, clinical and MRI follow-up examination.

RESULTS

Non-EPI-DW sequences depicted 9 of 10 residual cholesteatomas. The only lesion missed was a 2-mm cholesteatoma in an examination degraded by motion artifacts in a child. All other diagnosed cholesteatomas measured between 2 and 6 mm. Sensitivity, specificity, positive predictive value, and negative predictive value were 90, 100, 100, and 96%, respectively.

CONCLUSION

Except for motion artifact-degraded examinations, non-EPI-DW MRI is able to detect even very small residual cholesteatoma after first-stage surgery by showing a high-signal intensity lesion. It has the capability of selecting patients for second-look surgery, avoiding unnecessary second-look surgery.

Imaging of the opacified middle ear

Middle ear opacification on imaging studies performed in a non-traumatic setting mostly reflects chronic inflammatory/infectious disease. In some of these patients an underlying cholesteatoma will be found. High-resolution computed tomography examinations and magnetic resonance imaging are often used in the work-out of the disease. High-resolution computed tomography of the opacified middle ear serves to describe the status of the ossicular chain, and its suspensory apparatus, as well as the status of the tympanic and mastoid wall. When ossicular erosions are visualized, the probability of a present cholesteatoma is about 90%. Whereas high-resolution computed tomography is not able to differentiate cholesteatoma from other types of opacification, magnetic resonance imaging is. The combined use of delayed post-Gd T1-weighted images and non-EPI based DWI seems to be the actual best option on this matter.

The value of magnetic resonance imaging in the diagnosis of residual or recurrent acquired cholesteatoma after canal wall-up tympanoplasty

OBJECTIVE

The value of magnetic resonance imaging (MRI) in the diagnosis of recurrent or residual cholesteatoma after canal wall-up tympanoplasty is studied in a retrospective cohort study at a tertiary referral center.

PATIENTS

A total of 31 patients, who underwent 32 canal wall-up tympanoplasty procedures with MRI before revision surgery, were included in the study.

INTERVENTIONS

MRI examination, using both the conventional and echo-planar diffusion-weighted sequences, was performed, with additional spin echo diffusion-weighted MRI sequences in 4 patients. All patients were treated with a canal wall-up tympanoplasty.

MAIN OUTCOME MEASURES

The presence of residual or recurrent cholesteatoma at revision surgery is matched with preoperative findings on MRI.

RESULTS

MRI could correctly detect the residual disease in 54.5% of the surgically matched residual or recurrent cholesteatomas. MRI yielded a false-negative result in 45.5%. There was 1 false-positive result (10%). Sensitivity, specificity, and positive and negative predictive values of MRI were 54.4%, 90%, 92.3%, and 47.4%, respectively.

CONCLUSION

Preoperative MRI could correctly detect residual or recurrent cholesteatoma in somewhat over half the cases. A high number of false-negative results were obtained. At thismoment, MRI cannot yet replace revision surgery.

[Value of diffusion-weighted MR imaging in the detection of middle ear cholesteatoma]

OBJECTIVE

This study, was conducted to determine the clinical value of diffusion-weighted MR imaging (DWI) in detecting the presence of cholesteatoma.

SUBJECT AND METHODS

Fifty-six patients (21 female and 35 male patients; mean age, 43 years) who underwent middle ear surgery were referred to the radiology department for a preoperative DWI study.

RESULTS

DWI depicted 41 out of 48 cholesteatomas involving the middle ear cavity (sensitivity, 85.4%). Seven patients with middle ear cholesteatoma who showed negative DWI findings (false-negative cases) had limited keratin accumulation due to simple atelectasis or meticulous evacuation of keratin debris before the MRI study. No falsepositive cases were found in this study (specificity, 100%). The positive predictive value and negative predictive value were 100% and 53.3%, respectively. The minimum size of middle ear cholesteatoma detected by the current MRI system was 5mm.

CONCLUSION

Diffusion-weighted MR imaging was useful for the detection of middle ear cholesteatoma.

Posterior petrous face meningiomas: an algorithm for surgical management

OBJECTIVE

The objective of the present study was to report our surgical strategy in the management of 81 patients with posterior petrous face meningiomas.

STUDY DESIGN

Retrospective study.

SETTING

This study was conducted at a quaternary private otology and cranial base center.

PATIENTS

Of 139 patients with posterior fossa meningioma, 81 occurred on the posterior petrous face of the temporal bone and were the object of this study.

INTERVENTIONS

Thirty-one patients were approached by the enlarged translabyrinthine approach. The enlarged translabyrinthine approach with transapical extension Type II was performedin 29 patients. The combined retrosigmoid-retrolabyrinthine approach was chosen in 8 cases. The modified transcochlear approach Type A with permanent posterior transposition of the facial nerve (FN) was performed in 6 patients. Two patients underwent a retrolabyrinthine subtemporal transapical approach. One patient underwent a transpetrous middle cranial fossa approach. Four patients with intracanalicular meningiomas were operated on through the enlarged middle cranial fossa approach.

RESULTS

Total removal of the tumor (Simpson Grades I and II) was achieved in most patients (92.5%). The FN was anatomically preserved in 79 of the 81 (97.5%) patients. Five patients had less than 1 year follow-up, and 2 patients were lost to follow-up and were excluded in evaluation of the final FN outcome. At 1-year follow-up, 46 patients (63%) had Grade I to II, 19 (26%) had Grade III, 4 (5.4%) had Grade IV, 1 (1.3%) had Grade V, and 3 (4.1%) had Grade VI. Hearing-preserving surgery was attempted in 15 patients (18.5%) with preoperative serviceable hearing. Of these 15 patients, 11 had their hearing preserved at the same preoperative level, and 4 experienced postoperative deafness. Postoperatively, a new deficit of 1 or more of the lower cranial nerves was recorded in 3 patients. One patient experienced subcutaneous cerebrospinal fluid collection that required surgical management.

CONCLUSION

Total tumor removal (Simpson Grades I-II) remains our treatment of choice and takes priority over hearing preservation. Subtotal resection is indicated for older and debilitated patients with giant lesions to relieve the tumor compression on the cerebellum and brainstem. Subtotal removal is also preferred in the face of the absence of a plane of cleavage between the tumor and the brainstem, in the presence of encasement of vital neurovascular structures, in elderly patients with tumors adherent to preoperatively normal facial or lower cranial nerves.