Value for combination of T1WI star -VIBE with TWIST -VIBE dynamic contrast -enhanced MRI in distinguishing lung nodules / 中南大学学报(医学版)

OBJECTIVES@#With the increasing detection rate of lung nodules, the qualitative problem of lung nodules has become one of the key clinical issues. This study aims to evaluate the value of combining dynamic contrast-enhanced (DCE) MRI based on time-resolved imaging with interleaved stochastic trajectories-volume interpolated breath hold examination (TWIST-VIBE) with T1 weighted free-breathing star-volumetric interpolated breath hold examination (T1WI star-VIBE) in identifying benign and malignant lung nodules.@*METHODS@#We retrospectively analyzed 79 adults with undetermined lung nodules before the operation. All nodules of patients included were classified into malignant nodules (n=58) and benign nodules (n=26) based on final diagnosis. The unenhanced T1WI-VIBE, the contrast-enhanced T1WI star-VIBE, and the DCE curve based on TWIST-VIBE were performed. The corresponding qualitative [wash-in time, wash-out time, time to peak (TTP), arrival time (AT), positive enhancement integral (PEI)] and quantitative parameters [volume transfer constant (Ktrans), interstitium-to-plasma rate constant (Kep), and fractional extracellular space volume (Ve)] were evaluated. Besides, the diagnostic efficacy (sensitivity and specificity) of enhanced CT and MRI were compared.@*RESULTS@#There were significant differences in unenhanced T1WI-VIBE hypo-intensity, and type of A, B, C DCE curve type between benign and malignant lung nodules (all P<0.001). Pulmonary malignant nodules had a shorter wash-out time than benign nodules (P=0.001), and the differences of the remaining parameters were not statistically significant (all P>0.05). After T1WI star-VIBE contrast-enhanced MRI, the image quality was further improved. Compared with enhanced CT scan, the sensitivity (82.76% vs 80.50%) and the specificity (69.23% vs 57.10%) based on MRI were higher than that of CT (both P<0.001).@*CONCLUSIONS@#T1WI star-VIBE and dynamic contrast-enhanced MRI based on TWIST-VIBE were helpful to improve the image resolution and provide more information for clinical differentiation between benign and malignant lung nodules.

Application of 3D free-breathing Star VIBE sequence in abdominal enhanced MR in children / 中国医学影像技术

Objective To explore the application value of 3D free-breathing Star VIBE sequence in abdominal contrast-enhanced MR scanning of children. Methods Totally 72 children with abdominal lesions underwent contrast-enhanced MR scanning with 3D free-breathing Star VIBE sequence and turbo fast low angle shot (tfl) sequence, respectively. The enhanced T1W images obtained with two scanning sequences were scored subjectively, and SNR and CNR were calculated objectively. Results The scores of respiratory motion artifacts, intrahepatic vascular and inferior vena cava structure display, gastrointestinal peristalsis artifacts, lesion clarity and overall image quality score on 3D free-breathing Star VIBE sequence images were higher than those on tfl sequence images (all P<0.001). SNR and CNR of 3D free breathing Star VIBE sequence were 25.14 (20.42, 30.50), 9.20 (7.36, 10.42), of tfl sequence were 20.67 (19.00, 23.50) and 6.08(3.00, 8.50), respectively. SNR and CNR of 3D free-breathing Star VIBE sequence were higher than those of tfl sequence (all P<0.001). Conclusion 3D free-breathing Star VIBE sequence can significantly reduce motion artifacts and increase SNR and CNR, demonstrating important clinical value in diagnosis of abdominal diseases in children.