title: Correlation of phase values with CT Hounsfield and R2* values in calcified neurocysticercosis.
abstract: OBJECTIVE
  To correlate phase and R2* derived from susceptibility-weighted magnetic resonance imaging (MRI) with computed tomography-Hounsfield (CT-HU) values in calcified neurocysticercosis and to evaluate phase imaging in the assessment of calcified neurocysticercosis.
  
  
  METHODS
  Thirty-five patients with 52 calcified lesions underwent both CT and MRI. Phase and R2* were calculated from multi-echo 3D-T2-star-weighted-angiography data. MRI and CT data were coregistered using mutual information. Spearman's correlation was performed between quantitative phase and CT-HU and R2* values. The Mann-Whitney U-test was used to see differences between CT-HU and R2* values from corresponding positive and negative phase regions.
  
  
  RESULTS
  The median values of CT-HU and R2* from regions with positive and negative phase were found to be 142.10 (range: 41.89-491.75) and 68.5/sec (range: 20-110/sec) and 137.30 (range: 30.83-458.88) and 69/sec (range: 0-110/sec), respectively. There was a significant correlation of positive phase values with corresponding CT-HU and R2* values. In addition, there was a significant correlation of R2* and CT-HU with negative phase values.
  
  
  CONCLUSIONS
  We conclude that there is a significant correlation between negative and positive phase with CT-HU and R2* values, suggesting that the CT hyperdense lesion may have both calcium and other minerals, which can be differentiated using phase imaging. Conventional MRI should include phase imaging to detect calcified neurocysticercosis.
authors: Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India.
authors: B
authors: B
authors: Roy
authors: S
authors: S
authors: Verma
authors: R
authors: R
authors: Awasthi
authors: R K
authors: RK
authors: Rathore
authors: R
authors: R
authors: Venkatesan
authors: S A
authors: SA
authors: Yoganathan
authors: J K Maria
authors: JK
authors: Das
authors: K N
authors: KN
authors: Prasad
authors: R K
authors: RK
authors: Gupta
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000175:diagnosis / Q000000981:diagnostic imaging; D002114:Calcinosis / Q000175:diagnosis / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015233:Models, Statistical; D020019:Neurocysticercosis / Q000175:diagnosis / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000379:methods*