Fig. 1
Schematic structure of the DWI phantom. The B-1000 trace-weighted images shown under (C) and the corresponding ADC map are examples from a scan series acquired using rs-EPI-DWI. The cylindrical phantom (height: 170 mm, diameter: 150 mm) comprises four compartments (from left to right, see (A) and (C)). The first compartment serves as a homogenous quality control region and simulates healthy neuronal tissue defined as gray matter with an ADC of 0.8 × 10⁻³ mm²/s (ADCGM). The second compartment contains six lesions simulating cytotoxic edema with restricted diffusion (ADCRD: 0.5 × 10⁻³ mm²/s) embedded in the ADCGM matrix (ADCGM: 0.8 × 10⁻³ mm²/s). The six lesions have diameters of 10 mm, 7 mm, 5 mm, 4 mm, 3 mm and 2 mm. The reduction in lesion size should serve to evaluate the sequences in the imaging of very small ischemic pathologies and at the same time make it possible to assess the influence of lesion size on image quality. The third compartment, also a quality control region, simulates a homogenous matrix of cytotoxic edema caused by restricted diffusion with an ADC of 0.5 × 10⁻³ mm²/s (ADCRD). Finally, a Siemens star at the phantom’s end facilitates resolution comparisons. Subpanels (A) and (B) source: Image © HQ Imaging, modified by the authors. Used with permission of Dr. Michael Bach.
