Liver metastases: detection by phase-contrast MR imaging.

Area of Science:

• Radiology
• Medical Imaging
• Oncology

Background:

• Metastatic liver cancer detection relies on accurate imaging.
• Conventional magnetic resonance (MR) imaging pulse sequences have limitations in differentiating cancerous tissue from the liver.
• Phase-contrast imaging offers a potential improvement for MR imaging sequences.

Purpose of the Study:

• To evaluate the effectiveness of phase-contrast (opposed-phase) pulse sequences compared to conventional (in-phase) sequences for detecting metastatic liver cancers.
• To quantify the impact of phase-contrast imaging on signal-difference-to-noise (SD/N) ratios for various MR pulse sequences.

Main Methods:

• Forty patients with biopsy-proven metastatic liver cancers were studied.
• MR imaging was performed using conventional and phase-contrast pulse sequences.
• Signal-difference-to-noise (SD/N) ratios between cancerous tissue and liver were measured to assess pulse-sequence performance.

Main Results:

• T2-weighted spin-echo (SE) pulse sequences showed improved SD/N when used with the phase-contrast technique (P < .001 in 72% of patients).
• SE 2,000/30 opposed-phase images demonstrated significantly better SD/N compared to in-phase images.
• T1-weighted SE and inversion recovery pulse sequences showed deteriorated SD/N with phase-contrast imaging.

Conclusions:

• Phase-contrast imaging significantly improves the performance of T2-weighted SE pulse sequences for detecting metastatic liver cancer.
• The observed changes in SD/N correlated with enhanced image appearance and lesion detectability.
• Routine use of phase-contrast imaging is recommended with T2-weighted SE sequences for liver cancer detection.