Perfusion MR imaging with a superparamagnetic iron oxide using T2-weighted and susceptibility-sensitive echoplanar sequences: evaluation of tumor vascularity in hepatocellular carcinoma

AJR Am J Roentgenol. 1999 Jul;173(1):207-13. doi: 10.2214/ajr.173.1.10397128.

Abstract

Objective: The study purpose was to examine the usefulness of perfusion echoplanar MR imaging with a superparamagnetic iron oxide (SHU-555A) for evaluating the vascularity of hepatocellular carcinomas.

Subjects and methods: Twenty-two patients with 32 hepatocellular carcinomas underwent perfusion imaging with bolus injection (0.7-1.1 ml) of SHU-555A. Echoplanar sequences included multishot spin-echo (17 patients) and single-shot gradient-echo (five patients) imaging. Image acquisition was repeated every 30 sec for 3 min with the multishot spin-echo sequence and every 2 sec for 100 sec with the single-shot gradient-echo sequence. Lesion signal intensity versus time curves were created for quantitative analysis.

Results: Transient decreases in tumor signal intensity (28.8% with multishot spin-echo and 63.3% with the single-shot gradient-echo) were seen in the perfusion phase. These decreases in signal intensity were statistically significantly (p < .01) different for each histologic type of hepatocellular carcinoma (poorly differentiated, 43.3%; well differentiated, 18.4%; and moderately differentiated, 24.8%). After the perfusion phase, the tumor signal intensities rapidly recovered. The multishot spin-echo sequence could detect some signal changes even in lesions smaller than 1 cm.

Conclusion: Hepatocellular carcinoma vascularity can be evaluated with perfusion echoplanar imaging with SHU-555A. Because of its excellent temporal resolution, the single-shot gradient-echo echoplanar sequence detects the transient signal decrease in most lesions. The high image quality of the multishot spin-echo echoplanar sequence allows evaluation of the vascularity of even very small lesions.

MeSH terms

  • Aged
  • Carcinoma, Hepatocellular / blood supply*
  • Carcinoma, Hepatocellular / diagnosis
  • Contrast Media*
  • Dextrans
  • Echo-Planar Imaging
  • Ferrosoferric Oxide
  • Humans
  • Iron*
  • Liver Neoplasms / blood supply*
  • Liver Neoplasms / diagnosis
  • Magnetic Resonance Imaging*
  • Magnetite Nanoparticles
  • Male
  • Middle Aged
  • Oxides*

Substances

  • Contrast Media
  • Dextrans
  • Magnetite Nanoparticles
  • Oxides
  • Iron
  • ferumoxides
  • Ferrosoferric Oxide