Diffusion-weighted magnetic resonance imaging in the management of cholesteatoma

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.

MRI as an Alternative to Second Look Mastoid Surgery

The main goal of surgery of cholesteatoma is eradication of the disease and revision surgery is indicated when a dry and safe ear has not been achieved. Residual cholesteatoma usually occurs at the sites that are difficult to reach with an operating microscope, such as posterior tympanum and anterior epitympanic recess. Computed tomography can be performed to delineate the extent of disease. High-resolution computed tomography scanning is important for planning for surgery and is indicated for all revision mastoid operations. Magnetic resonance imaging is superior to computed tomography in tissue characterization for diagnosis of recurrent cholesteatoma. To evaluate the cases of recurrent cholesteatoma comparing the intraoperative surgical findings with the preoperative MRI radiological findings and if the preoperative MRI can replace the second look surgery for cholesteatoma. This study was applied on 60 patients that have a recurrent cholesteatoma after previous mastoid surgery. A preoperative radiological evaluation was done by Magnetic resonance, surgical management was done by canal wall up or canal wall down mastoidectomy to exclude residual disease. Then, radiological, and surgical findings correlation was done. Diffusion-weighted MRI successfully detected 42 cases out of the 45 cases of surgically proved cholesteatoma, it has accuracy 95%, sensitivity 93.33%, specificity 100%, PPV 100% and NPV 83.33%. MRI is better than CT in tissue characterization for diagnosis of recurrent cholesteatoma, and can replace the unnecessary second look surgery of cholesteatoma.

The accuracy and sensitivity of diffusion-weighted magnetic resonance imaging with Apparent Diffusion Coefficients in diagnosis of recurrent cholesteatoma

OBJECTIVE

To evaluate the accuracy and sensitivity of diffusion-weighted magnetic resonance imaging with ADC value combined with MDCT in evaluating recurrent cholesteatoma.

PATIENTS

Thirty patients (20 females and 10 males), their age ranged from 10 to 40years, had undergone a tympanomastoid surgery for a cholesteatoma of the middle ear underwent MDCT and MR DWI examination before second- or third-look surgery from May 2015 to October 2016.

RESULTS

CT showed partial opacification of the tympanomastoid cavity in 10 ears and complete opacification in 21 ears. CT detects 10 cases out of 20 cases of recurrent cholesteatoma with sensitivity 47.6%, specificity 100%, and NPP 47.6%. DWI depicted 21 out of 20 cases proved cholesteatoma patients (sensitivity 100%, specificity 90%, PPV 95.2% and P value is 0.001). All MRI of patients without cholesteatoma were correctly interpreted as showing negative findings for cholesteatoma (specificity = 100%). The ADC of cholesteatoma group (21 ears) were ranged from 553 to 759 × 10-3 mm2/s and the ADCs of non cholesteatoma group (10 ears) was ranged from 1495.8 to 1766.8 × 10-3 mm2/s. Cut off value of cholesteatoma is ≤759 × 10-3 mm2/s.

CONCLUSION

MR DWI with ADC combined with MDCT has high sensitivity, specificity, accuracy in detecting recurrent cholesteatoma.

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.

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).

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.

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.

The diagnostic value of diffusion-weighted magnetic resonance imaging in detecting a residual cholesteatoma

In this evidence-based case report, we address the following clinical question: What is the predictive value of diffusion-weighted magnetic resonance imaging (DW MRI) for detecting a residual cholesteatoma in patients with chronic otitis media with cholesteatoma who have previously undergone a canal-wall-up procedure? We searched for relevant synonyms for the determinant, MRI, and for the outcome, cholesteatoma, and retrieved relevant publications in Embase, PubMed, Cinahl, and Web of Science by using search terms in the title and abstract fields. The search yielded 683 records, of which 11 were relevant and valid for our clinical question. We pooled the data of the MRI findings of the included studies by adding the two-by-two tables of the individual studies. For the eight echo planar imaging (EPI) DW MRI studies, this resulted in a pooled sensitivity, specificity, positive predictive value, and negative predictive value of 68 percent, 87 percent, 81 percent, and 78 percent, respectively. For the three non-echo planar (non-EPI) DW MRI studies, the sensitivity, specificity, positive predictive value, and negative predictive value were 97 percent, 97 percent, 97 percent, and 97 percent, respectively. DW MRI, especially the non-EPI DW MRI, appears to be a rather accurate method, as opposed to a standard second-look operation, for the follow-up of patients who have undergone a canal-wall-up procedure for a chronic otitis media with cholesteatoma and who have no clinical signs of recurrent cholesteatoma.

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.