title: Presacral epidermoid cyst: imaging findings with histopathologic correlation.
abstract: BACKGROUND
  The aim of this study was to determine the imaging characteristics of presacral epidermoid cysts and correlate the imaging findings with the histopathologic findings.
  
  
  METHODS
  We retrospectively reviewed sonographic, computed tomographic, and magnetic resonance examinations in four consecutive patients with a pathologically proven presacral epidermoid cyst. Imaging findings of the presacral epidermoid cyst were correlated with the histopathologic findings.
  
  
  RESULTS
  In all four patients, sonography showed a presacral mass with a heterogeneous low echogenicity, and computed tomography showed a discrete well-defined hypodense presacral mass with a thin wall. In the three patients who underwent magnetic resonance imaging, the mass showed a heterogeneous low signal intensity on the T1-weighted image and a high signal intensity with multiple small foci of low signal intensity in the nondependent portion of the mass on the T2-weighted image. These imaging findings correlated well with the pathologic results. Aggregates of keratinous material contributed to these imaging findings.
  
  
  CONCLUSIONS
  In the diagnosis of the presacral epidermoid cyst, sonographic and magnetic resonance imaging findings may be helpful.
authors: Department of Radiology, Gachon Medical College, Gil Medical Center, 1198, Kuwol-Dong, Namdong-Ku, Inchon, 405-760, South Korea.
authors: D M
authors: DM
authors: Yang
authors: M H
authors: MH
authors: Yoon
authors: H S
authors: HS
authors: Kim
authors: Y H
authors: YH
authors: Oh
authors: S Y
authors: SY
authors: Ha
authors: J H
authors: JH
authors: Oh
authors: H S
authors: HS
authors: Chung
authors: H S
authors: HS
authors: Kim
mesh_terms: D000328:Adult; D003952:Diagnostic Imaging; D004814:Epidermal Cyst / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D012189:Retrospective Studies; D012445:Sacrococcygeal Region / Q000473:pathology* / Q000601:surgery