Reliability and exactness of MRI-based volumetry: A phantom study

✍ Scribed by Andreas R. Luft; Martin Skalej; Dorothea Welte; Ruppert Kolb; Uwe Klose

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 579 KB
• Volume: 6
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.1880060421

✦ Synopsis

Abstract

This study investigated the influence of slice thickness. section orientation, contrast, shape, and sequence type on the exactness of MRI‐based volumetry. Ni‐doped agarose gel phantoms (4 to 46 ml) were scanned with a T1‐weighted three‐dimensional Fourier transform (FT) fast low‐angle shot (FLASH) and a multiecho two‐dimensional FT‐Turbo spin‐echo (SE) sequence. After segmentation with a three‐dimensional region‐growing algorithm, the geometric volume was measured considering the partial volume effect. The variability coefficient (Pearson) was .7%. The volumetric error increased with slice thickness, depending on the size and form of the object. Cross sections resulted in smaller error than longitudinal sections (finger‐shaped phantoms, nonisotropic image data). Three‐dimensional FT was superior to two‐dimensional FT imaging. Results of slice thickness and section orientation experiments can be explained by the partial volume effect. Higher errors in two‐dimensional FT imaging were caused by object movements between two interleaved acquisitions. The study shows a considerable influence of the imaging parameters on the exactness, which depends on size and form of the structure of interest.