Brain Tumor CE on T1-Cube versus 3D SPGR

Purpose: T1-Cube (GE HealthCare) is a relatively new 3-dimensional (3D) fast spin-echo (FSE)-based magnetic resonance (MR) imaging sequence that uses a variable flip angle to acquire gap-free volume scans. We compared the gadolinium enhancement characteristics of a heterogeneous population of brain tumors imaged by T1-Cube and then 3D fast spoiled gradient recall acquisition in steady state (3D FSPGR) 3-tesla MR imaging to identify the superior modality for specific diagnostic purposes. Methods: We examined 61 lesions from 32 patients using the 2 sequences after administration of gadopentetic acid (Gd-DTPA; 0.1 mmol/kg). Two neuroradiologists independently measured each lesion twice using a region-of-interest (ROI) method. We measured the contrast-to-noise ratio (CNR), the difference in signal intensity (SI) between the tumor and normal white matter relative to the standard deviation (SD) of the SI within the lesion, for both post-contrast 3D FSPGR and post-contrast T1-Cube images of the same tumor and compared modality-specific CNRs for all tumors and in subgroups defined by tumor size, enhancement ratio, and histopathology. Results: The mean CNR was significantly higher on T1-Cube images than 3D FSPGR images for the total tumor population (1.85 ± 0.97 versus 1.12 ± 1.05, P < 0.01) and the histologic types, i.e., metastasis (P < 0.01) and lymphoma (P < 0.05). The difference in CNR was even larger for smaller tumors in the metastatic group (4.95 to 23.5 mm2) (P < 0.01). In contrast, mean CNRs did not differ between modalities for high grade glioma and meningioma. Conclusions: Gadolinium enhancement of brain tumors was generally higher when imaged by T1-Cube than 3D FSPGR, and T1-Cube with Gd enhancement may be superior to 3D FSPGR for detecting smaller metastatic tumors

短時間の造影ダイナミック灌流画像を用いた脳腫瘍の質的診断について

This study sought to determine the diagnostic utility of perfusion parameters derived from dynamic contrast-enhanced (DCE) perfusion MRI with a short acquisition time (approximately 3.5 min) in patients with glioma, brain metastasis, and primary CNS lymphoma (PCNSL). Twenty-six patients with 29 lesions (4 low-grade glioma, 13 high-grade glioma, 7 metastasis, and 5 PCNSL) underwent DCE-MRI in a 3 T scanner. A ROI was placed on the hotspot of each tumor in maps for volume transfer contrast Ktrans, extravascular extracellular volume Ve, and fractional plasma volume Vp. We analyzed differences in parameters between tumors using the Mann–Whitney U test. We calculated sensitivity and specificity using receiver operating characteristics analysis. Mean K trans values of LGG, HGG, metastasis and PCNSL were 0.034, 0.31, 0.38, 0.44, respectively. Mean Ve values of each tumors was 0.036, 0.57, 0.47, 0.96, and mean Vp value of each tumors was 0.070, 0.086, 0.26, 0.17, respectively. Compared with other tumor types, low-grade glioma showed lower Ktrans (P < 0.01, sensitivity = 88%, specificity = 100%) and lower Ve (P < 0.01, sensitivity = 96%, specificity = 100%). PCNSL showed higher Ve (P < 0.01, sensitivity = 100%, specificity = 88%), but the other perfusion parameters overlapped with those of different histology. Kinetic parameters derived from DCE-MRI with short acquisition time provide useful information for the differential diagnosis of brain tumors