Thornwaldt Cyst

Midline nasopharyngeal cyst of homogeneous high T2 signal was incidentally found on MRI brain. It is well circumscribed, embedded within nasopharyngeal mucosa between prevertebral muscles.
Thornwaldt cysts are benign developmental nasopharyngeal cysts covered by mucosa anteriorly and bounded by longus muscles posteriorly. They range from a few mm to 2-3cm in diameter. Usually incidental finding on MR and rarely has any clinical significance.
Reference: Harnsberger R. Diagnostic Imaging: Head & Neck Amirsys 2004
Credit: Dr Ahmed Haroun
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