Detection of hemorrhagic hypointense foci in the brain on susceptibility-weighted imaging clinical and phantom studies

Acad Radiol. 2007 Sep;14(9):1011-9. doi: 10.1016/j.acra.2007.05.013.


Rationale and objectives: To determine the sensitivity of susceptibility-weighted imaging (SWI) for depicting hemorrhagic hypointense foci of the brain in comparison with gradient-recalled echo (GRE)- and GRE-type single-shot echo-planar imaging (GREI, GRE-EPI), and to assess the basic characteristics of the susceptibility effect by using a phantom.

Materials and methods: We prospectively examined 16 patients (9 males, 7 females, aged 10-74 years, mean 43 years) with hypointense foci using SWI, GREI, and GRE-EPI at a 1.5-T magnetic resonance (MR) unit. The contrast-to-noise ratio (CNR), sensitivity to small hypointese foci, and artifacts were evaluated. To assess the basic characteristics of SWI, we performed a phantom study using different concentrations of superparamagnetic iron oxide (SPIO).

Results: The CNR of lesions was significantly greater for SWI than the other images (P < .0001). SWI detected the greatest number of small hypointense foci, even in the near-skull-base and infratentorial regions. Quantitative and qualitative analyses in our clinical and phantom studies demonstrated that the degree of artifacts was similar with SWI and GREI.

Conclusion: SWI was best for detecting small hemorrhagic hypointense foci. Artifacts of SWI were similar to GREI.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Brain / pathology*
  • Child
  • Echo-Planar Imaging / instrumentation
  • Echo-Planar Imaging / methods*
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted / methods*
  • Intracranial Hemorrhages / diagnosis*
  • Male
  • Middle Aged
  • Phantoms, Imaging
  • Reproducibility of Results
  • Sensitivity and Specificity