Focal hepatic lesions: comparative MR imaging at 0.5 and 1.5 T

Area of Science:

• Radiology
• Medical Imaging
• Hepatology

Background:

• Accurate detection of focal hepatic lesions is crucial for diagnosing and staging malignancy.
• Magnetic resonance imaging (MRI) offers various sequences for liver lesion characterization, but optimal sequence selection remains an area of investigation.

Purpose of the Study:

• To compare the relative sensitivities of T1-weighted spin echo (SE), T1-weighted inversion recovery (IR), and T2-weighted SE magnetic resonance imaging (MRI) sequences for detecting focal hepatic lesions at 0.5 T and 1.5 T.

Main Methods:

• Twenty-nine patients with known or suspected malignancy underwent identical T1-weighted (SE and IR) and T2-weighted SE MRI at 0.5 T and 1.5 T.
• Lesion detection rates for each sequence at both field strengths were recorded and compared.

Main Results:

• At 0.5 T, IR detected 98 lesions, T2-weighted SE detected 96, and T1-weighted SE detected 86.
• At 1.5 T, T2-weighted SE detected 99 lesions, IR detected 93, and T1-weighted SE detected 70.
• T1-weighted SE at 1.5 T was significantly inferior for lesion detection. T1-weighted SE at 0.5 T was inferior for detecting left lobe lesions compared to IR and T2-weighted sequences.

Conclusions:

• T1-weighted inversion recovery and T2-weighted spin echo sequences are optimal for detecting focal hepatic lesions at both 0.5 T and 1.5 T.
• No significant difference in lesion detection was observed based on magnetic field strength.
• T1-weighted SE sequences, particularly at 1.5 T, demonstrated lower sensitivity for detecting focal hepatic lesions.