Incidental mastoid opacification in children on MRI

Area of Science:

• Radiology
• Pediatric Imaging
• Otology

Background:

• Mastoid cavity opacification is frequently noted on cross-sectional imaging for non-otological reasons.
• Fluid or mucosal thickening in the mastoid does not automatically mean mastoiditis.
• This study aimed to provide evidence confirming this common observation.

Purpose of the Study:

• To determine the prevalence of mastoid opacification in children undergoing outpatient brain MRI.
• To assess if mastoid opacification is an incidental finding unrelated to otological conditions.

Main Methods:

• Retrospective analysis of 515 outpatient children (15 days to 18 years) who had brain MRI.
• Exclusion of patients with skull base trauma or radiation history.
• Statistical analysis including proportion, confidence intervals, and chi-square tests for prevalence based on demographics and symptoms.

Main Results:

• Mastoid opacification was found in 21.4% (110/515) of children.
• Higher opacification rates were observed in younger children: 41.7% in those under 1 year and 47.5% between 1-2 years.
• Prevalence analysis by gender, age, and symptoms was performed.

Conclusions:

• Radiologists' reports of mastoid opacification (fluid or thickening) in children should not be the sole basis for diagnosing mastoiditis.
• Incidental mastoid opacification is a frequent finding on brain MRI in pediatric patients.
• Clinical correlation is essential when interpreting mastoid findings on imaging.