, Volume 52, Issue 12, pp 1179–1184 | Cite as

Nasal polyps with metaplastic ossification: CT and MR imaging findings

  • Yi Kyung Kim
  • Hyung-Jin KimEmail author
  • Jinna Kim
  • Seung-Kyu Chung
  • Eunhee Kim
  • Young-Hyeh Ko
  • Sung Tae Kim
Head and Neck Radiology



Metaplastic ossification is a rare event in nasal polyps. The purpose of this study was to review the computed tomography (CT) and magnetic resonance (MR) imaging findings of nasal polyps with metaplastic ossification.


CT (n = 5) and MR (n = 3) images of five patients (four men and one woman; mean age, 59 years) with surgically proven nasal polyp with metaplastic ossification were retrospectively reviewed. The location and morphologic characteristics of metaplastic ossification were documented as well.


All lesions were seen as lobulated (n = 3), ovoid (n = 1), or dumbbell-shaped (n = 1) benign-looking masses with a mean size of 3.7 cm (range, 2.4–6.5 cm), located unilaterally in the posterior nasal cavity and nasopharynx (n = 2), posterior nasoethmoidal tract (n = 2), and maxillary sinus and nasal cavity (n = 1). Compared with the brain stem, the soft tissue components of all lesions demonstrated isoattenuation on precontrast CT scans, slight hypointensity on T1-weighted MR images, and hyperintensity on T2-weighted MR images. On contrast-enhanced MR images, heterogeneous enhancement with marked peripheral enhancement was seen in two and homogeneous moderate enhancement in one. All lesions contained centrally located radiodense materials on CT scans, the shape of which was multiple clustered in three, single nodular in one, and single large lobulated in one.


Although rare, metaplastic ossification can occur within nasal polyps. The possibility of its diagnosis may be raised when one sees a benign-looking sinonasal mass with centrally located radiodense materials on CT scans. MR imaging may be useful when mycetoma or inverted papilloma cannot be ruled out on CT scans.


Nasal polyp Metaplastic ossification Computed tomography Magnetic resonance imaging 


Conflict of interest statement

We declare that we have no conflict of interest.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Yi Kyung Kim
    • 1
  • Hyung-Jin Kim
    • 1
    Email author
  • Jinna Kim
    • 2
  • Seung-Kyu Chung
    • 3
  • Eunhee Kim
    • 1
  • Young-Hyeh Ko
    • 4
  • Sung Tae Kim
    • 1
  1. 1.Department of Radiology, Samsung Medical CenterSungkyunkwan University School of MedicineSeoulSouth Korea
  2. 2.Department of RadiologyYonsei University College of MedicineSeoulSouth Korea
  3. 3.Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical CenterSungkyunkwan University School of MedicineSeoulSouth Korea
  4. 4.Department of Pathology, Samsung Medical CenterSungkyunkwan University School of MedicineSeoulSouth Korea

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