Preoperative detection of malignant liver tumors: Comparison of 3D-T2-weighted sequences with T2-weighted turbo spin-echo and single shot T2 at 1.5 T

Comparison of ability of lesion detection of two MRI sequences of T2WI HASTE and T2WI BLADE for hepatocellular carcinoma

We investigated the diagnostic accuracy of 2 magnetic resonance imaging (MRI) sequences of T2 weighted image (T2WI) half-Fourier acquired single turbo spin-echo (HASTE) and BLADE, for hepatocellular carcinoma (HCC) detection. From November 2010 to August 2018, patients diagnosed with HCC and regularly followed up, and who underwent MRI with 2 kinds of T2WI, were included in this study. The diagnosis of HCC was established based on histopathological findings or LI-RADS 4 and 5 by image. The sensitivities and positive predictive value for the detection of HCC by T2WI HASTE and BLADE were compared for each sequence. Quantitative assessment with lesion contrast-to-noise ratio and visual rating scoring of image quality, based on factors such as artifact, margin of organs, and vessel sharpness of the 2 sequences, were compared. No significant differences in lesion detection were observed based on paired comparison of all lesions and lesions larger than 1 cm across both sequences. The sensitivity was higher in larger than 1cm group in all sequences. The HASTE sequence had less motion artifact, but the BLADE images had advantage in edge sharpness of organs and vessels. The HASTE without fat-saturation seems to have better overall image quality. The lesions contrast-to-noise ratio of the 2 image modalities were not significantly different. Compared with T2 BLADE, T2 HASTE may be a more effective protocol for detecting HCC larger than 1 cm without loss of sensitivity. The accuracy of data from 2 T2WI protocols could be applied to streamline MRI protocols of HCC screening and surveillance.

Fast T2-weighted liver MRI: Image quality and solid focal lesions conspicuity using a deep learning accelerated single breath-hold HASTE fat-suppressed sequence

PURPOSE

Acceleration of MRI acquisitions and especially of T2-weighted sequences is essential to reduce the duration of MRI examinations but also kinetic artifacts in liver imaging. The purpose of this study was to compare the acquisition time and the image quality of a single-shot fat-suppressed turbo spin-echo (TSE) T2-weighted sequence with deep learning reconstruction (HASTE_DL) with that of a fat-suppressed T2-weighted BLADE TSE sequence in patients with focal liver lesions.

MATERIALS AND METHODS

Ninety-five patients (52 men, 43 women; mean age: 61 ± 14 [SD]; age range: 28-87 years) with 42 focal liver lesions (17 hepatocellular carcinomas, 10 sarcoidosis lesions, 9 myeloma lesions, 3 liver metastases and 3 focal nodular hyperplasias) who underwent liver MRI at 1.5 T including HASTE_DL and BLADE sequences were retrospectively included. Overall image quality, noise level in the liver, lesion conspicuity and sharpness of liver lesion contours were assessed by two independent readers. Liver signal-to-noise ratio (SNR) and lesion contrast-to-noise ratio (CNR) were measured and compared between the two sequences, as well as the mean duration of the sequences (Student t-test or Wilcoxon test for paired data).

RESULTS

Median overall quality on HASTE_DL images (3; IQR: 3, 3) was significantly greater than that on BLADE images (2; IQR: 1, 3) (P < 0.001). Median noise level in the liver on HASTE_DL images (0; IQR: 0, 0.5) was significantly lower than that on BLADE images (1; IQR: 1, 2) (P < 0.001). On HASTE_DL images, mean liver SNR (107.3 ± 39.7 [SD]) and mean focal liver lesion CNR (87.0 ± 76.6 [SD]) were significantly greater than those on BLADE images (67.1 ± 23.8 [SD], P < 0.001 and 48.6 ± 43.9 [SD], P = 0.027, respectively). Acquisition time was significantly shorter with the HASTE_DL sequence (18 ± [0] s; range: 18-18 s) compared to BLADE sequence (152 ± 47 [SD] s; range: 87-263 s) (P < 0.001).

CONCLUSION

By comparison with the BLADE sequence, HASTE_DL sequence significantly reduces acquisition time while improving image quality, liver SNR and focal liver lesions CNR.