The Great Debate: MRI Versus Second-Look Surgery for Cholesteatoma

by Sujana S. Chandrasekhar, MD, and Samantha Anne, MD, MS •

Unfortunately, it is a well-recognized aphorism that to have a busy surgical otology practice, one needs only 10 children with cholesteatoma as patients. This highlights the high rates of recidivism (a term used to describe both recurrent and residual cholesteatoma) of this condition after surgical treatment. A meta-analysis by Yasser Shewel, MD, and colleagues in 2020 showed recidivism rates ranged from 5.26% to 80% (average of 27.6%) in individuals with canal wall up (CWU) mastoidectomies and from 0% to 48% (average of 17.4%) when the canal wall was down (CWD) (Egyptian J Otolaryngol. 2020. doi.org/10.1186/s43163-020-00043-z). Even with endoscopes, the reported rates of recidivism are still high, ranging from 18%-24% (Otolaryngol Head Neck Surg. 2017. doi: 10.1177/0194599817729136; Otolaryngol Head Neck Surg. 2016. doi: 10.1177/0194599815622441).

The goals of cholesteatoma surgery in all ages are:

  • Minimize the number of operations to create a safe, dry, hearing ear;
  • Minimize anesthetic exposure for surgery and imaging;
  • Minimize radiation exposure;
  • Avoid delay in necessary surgery;
  • Avoid unnecessary surgery;
  • Avoid future complications; and
  • Prevent the child (or adult) from developing a fear of medical visits.

With this in mind, the matter up for discussion here is HOW do we monitor patients’ ears most effectively—via imaging with computed tomography/magnetic resonance imaging (CT/MRI) or via second-look surgery? This remains a Great Debate.

Imaging

There are different imaging options for cholesteatoma surveillance. Non-contrast CT scan of the temporal bones is often used to delineate disease and bony involvement, as well as to look for the status of ossicles, tegmen, inner ear, and facial nerve canal. Modern techniques have dramatically reduced the risk of radiation exposure to a minimal level; however, the use of CT, even temporal subtraction CT, in monitoring for cholesteatoma is fraught with difficulties in differentiating recurrent/residual lesions versus inflammatory tissue or granulation (Jpn J Radiol. 2022. doi: 10.1007/s11604-021-01209-2).

MRI scans of the temporal bones are increasingly used in cholesteatoma surveillance as the techniques advance, with increasing accuracy and the ability to avoid radiation exposure. Various techniques of MR imaging can be used for this purpose:

  • Echoplanar (EP) Diffusion-Weighted Imaging (DWI)

    – Rapid acquisition—”single shot”

    – Prone to artifacts/distortion

    – Poor detection if the disease is less than 5 mm

  • RESOLVE Echoplanar DWI (RS-DWI)

    – Better resolution

    – 2-3 mm slice thickness

    – Added coronal images

    – Cholesteatoma detection: sensitivity is 88%; specificity is 96%

  • Non-Echoplanar DWI

    – 20-30 minutes in the scanner

    – Multiple excitation pulses, longer echo time, higher signal-to-noise ratio (SNR)