title: Magnetic resonance susceptibility weighted imaging in detecting intracranial calcification and hemorrhage.
abstract: BACKGROUND
  Computed tomography (CT) is better than routine magnetic resonance imaging (MRI) in detecting intracranial calcification. This study aimed to assess the value of MR susceptibility weighted imaging (SWI) in the detection and differentiation of intracranial calcification and hemorrhage.
  
  
  METHODS
  Enrolled in this study were 35 patients including 13 cases of calcification demonstrated by CT and 22 cases of intracerebral hemorrhage. MR sequences used in all the subjects included axial T1WI, T2WI and SWI. The phase shift (PS) of calcification and hemorrhage on SWI was calculated and their signal features on corrected phase images were compared. The sensitivity of T1WI, T2WI and SWI in detecting intracranial calcification and hemorrhage was analyzed statistically.
  
  
  RESULTS
  The detection rate of SWI for cranial calcification was 98.2%, significantly higher than that of T1WI and T2WI. It was not significantly different from that of CT (P > 0.05). There were 49 hemorrhagic lesions at different stages detected on SWI, 30 on T2WI and 18 on T1WI. The average PS of calcification and hemorrhage was +0.734 +/- 0.073 and -0.112 +/- 0.032 respectively (P < 0.05). The PS of calcification was positive and presented as a high signal or the mixed signal dominated by a high signal on the corrected phase images, whereas the PS of hemorrhage was negative and presented as a low signal or the mixed signal dominated by a low signal.
  
  
  CONCLUSIONS
  SWI can accurately demonstrate intracranial calcification, not dependant on CT. Being more sensitive than routine MRI in detecting micro-hemorrhage, SWI may play an important role in differentiating cerebral diseases associated with calcification or hemorrhage.
authors.affiliation: Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China. zhuwenzhen@hotmail.com
authors.forename: Wen-zhen
authors.initials: WZ
authors.lastname: Zhu
authors.forename: Jian-pin
authors.initials: JP
authors.lastname: Qi
authors.forename: Chuan-jia
authors.initials: CJ
authors.lastname: Zhan
authors.forename: Hong-ge
authors.initials: HG
authors.lastname: Shu
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Cheng-yuan
authors.initials: CY
authors.lastname: Wang
authors.forename: Li-ming
authors.initials: LM
authors.lastname: Xia
authors.forename: Jun-wu
authors.initials: JW
authors.lastname: Hu
authors.forename: Ding-yi
authors.initials: DY
authors.lastname: Feng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001927:Brain Diseases / Q000175:diagnosis*; D002114:Calcinosis / Q000175:diagnosis*; D002543:Cerebral Hemorrhage / Q000175:diagnosis*; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged