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.