title: Intraparenchymal endodermal cyst with spontaneous intracystic hemorrhage in the temporal lobe of an adult.
abstract: BACKGROUND
  Endodermal cysts (EC) are rare but well-known congenial lesions of the central nervous system mainly located in the spinal subdural space. Intracranial ECs are rare and commonly encountered in the posterior cranial fossa as extra-axial lesions; an intraparenchymal location is exceedingly rare. A complete removal is the best surgical strategy and any residue can cause recurrence. It is necessary to exclude EC in patients with intracranial cystic lesions. We present a case of intraparenchymal EC with spontaneous intracystic hemorrhage in the temporal lobe of an adult.
  
  
  METHODS
  A 43-year-old man presented with headache and memory deterioration. Brain computed tomography and magnetic resonance imaging showed a slightly enhanced temporal lobe cystic lesion, which was homogenously hyperintense on T1-and T2-weighted images. There was a suspicion of brain abscess at admission. The lesion was totally removed with a left subtemporal craniotomy. Histological examination revealed an EC with intracystic hemorrhage.
  
  
  RESULTS
  The preoperative symptoms were relieved after surgery and 3-month follow-up magnetic resonance imaging found no cystic signs.
  
  
  CONCLUSIONS
  This case suggests that EC should be considered in the differential diagnosis of intracranial cystic lesions and a complete removal is the best strategy of choice.
authors.affiliation: Department of Neurosurgery Department of Pathology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Xin-Jie
authors.initials: XJ
authors.lastname: Bao
authors.forename: Xue-Yuan
authors.initials: XY
authors.lastname: Li
authors.forename: Qi-Pu
authors.initials: QP
authors.lastname: Wang
authors.forename: Xin-Yu
authors.initials: XY
authors.lastname: Ren
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Liang
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Ma
authors.forename: Ren-Zhi
authors.initials: RZ
authors.lastname: Wang
authors.forename: Jun-Ji
authors.initials: JJ
authors.lastname: Wei
mesh_terms: D000328:Adult; D020863:Central Nervous System Cysts / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D020300:Intracranial Hemorrhages / Q000209:etiology*; D008297:Male; D013702:Temporal Lobe