Table 1.
Parameters for EPI-DWI and STEAM-DWI.
Fig 1.
Comparison of isoDW images obtained by (a) EPI-DWI and (b) STEAM-DWI in a 15-year-old adolescent with epilepsy without pathological findings.
A brace leads to severe frontal susceptibility artifacts, which are much less pronounced in STEAM-DWI.
Fig 2.
Comparison of isoDW images obtained by (a) EPI-DWI and (b) STEAM-DWI in a 4-year-old boy with status post resection of craniopharyngeoma.
In contrast to EPI-DWI, the left-frontal pneumencephalus does not cause artifacts with STEAM-DWI. Please note the hyperintense changes in isoDWI which showed restricted diffusion in ADC, in the right hemisphere in both the fontal cortex and frontal white matter.
Fig 3.
Comparison of isoDW images obtained by (a) EPI-DWI and (b) STEAM-DWI in a 14-month-old girl with posttraumatic epidural hemorrhage and partial infarction in the area of the right posterior cerebral artery (postoperative situs).
Susceptibility effects due to the surgical foreign material on the calvaria and an intracranial pressure probe (in adjacent layer) result in moderate distortion and hyperintensity artifacts, which are not noticeable in STEAM-DWI. Please note that the hyperintense alterations in the EPI-DWI right frontal are exclusively due to artifacts. Depiction of the small hyperintense spot in the left crus cerebri in STEAM-DWI is inferior compared to EPI-DWI.
Fig 4.
Comparison of isoDW images obtained by (a) EPI-DWI and (b) STEAM-DWI in a 13-year-old girl with left-sided postseptal inflammation and abscess lateral to the rectus lateralis muscle into the temporalis muscle.
The diffusion restriction can be seen in both EPI-DWI and STEAM-DWI, but the morphological distortions and artificially increased signal at the anterior and posterior border of the conus make it difficult to accurately assess the extent of the abscess in EPI-DWI.
Table 2.
Visual judgment of resolution for EPI-DWI and STEAM-DWI on a Likert scale (range 1 to 3) in 208 patients.
Table 3.
Diagnostic confidence for EPI-DWI and STEAM-DWI on a Likert scale (range 1 to 3) in 208 patients.
Fig 5.
The contrast-to-noise ratio in isoDW images of STEAM-DWI is only about half that of EPI-DWI (mean CNR 58% vs. 112%).
Fig 6.
Corresponding ADC values as randomly obtained by EPI-DWI and STEAM-DWI.
On average (solid black line), STEAM-DWI values are 13% lower than those obtained by EPI-DWI (medians as dashed black line).