Whole-Body 3D T1-weighted MR Imaging in Patients with Prostate Cancer: Feasibility and Evaluation in Screening for Metastatic Disease

Abstract

Whole-body MR imaging is feasible with a 3D T1-weighted sequence and provides better SNR and CNR compared with 2D sequences, with a diagnostic performance that is as good or better for the detection of bone metastases and better for the detection of lymph node metastases.

Current whole-body MRI applications in the neurofibromatoses

“…Potential disadvantages of 3.0T MRI include B1 field inhomogeneities and susceptibility artifacts. 2,13 Work is ongoing to optimize this with technological advances such as continuous table motion and improved coils, which are expected to shorten acquisition and increase SNR. 2,25 With respect to specific sequences, the STIR sequence, with its combined T1 and T2 weighting, has been uniformly used in the WB-MRI investigations for PNST.…”

“…2,13 Work is ongoing to optimize this with technological advances such as continuous table motion and improved coils, which are expected to shorten acquisition and increase SNR. 2,25 With respect to specific sequences, the STIR sequence, with its combined T1 and T2 weighting, has been uniformly used in the WB-MRI investigations for PNST. Most pathologic processes, including tumors, are proton-rich with resultant prolonged T1 and T2 relaxation times and increased signal intensity on STIR images.…”

“…It has been extensively investigated for the detection and staging of visceral and osseous tumors [1][2][3][4][5][6] and is well-suited to tumor syndromes including neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), and schwannomatosis (SWN), [7][8][9] as these patients often have a high burden of tumors as well as large tumors that cross anatomic planes (figure). WB-MRI has been used to evaluate tumor burden and to characterize neoplasms in patients with NF syndromes [10][11][12][13][14][15][16][17][18][19][20][21][22][23] and is being used in some clinical trials to evaluate response to therapy (NCT01207687).…”

Practical aspects of prostate MRI: hardware and software considerations, protocols, and patient preparation

“…Identification of these lymph nodes is facilitated by the T1 contrast between the high signal intensity of visceral fat and lower signal intensity of large or irregularly shaped lymph nodes [47]. To ensure that lymph nodes in the drainage pathway are imaged during the exam, the T1-weighted scan prescription should extend superiorly to the aortic bifurcation [48].…”

“…To ensure that lymph nodes in the drainage pathway are imaged during the exam, the T1-weighted scan prescription should extend superiorly to the aortic bifurcation [48]. T1-weighted imaging is also useful to diagnose post-biopsy hemorrhage, which demonstrates high signal intensity [47]. Hemorrhage often has low T2 signal intensity, mimicking cancer, and may introduce significant artifact on DWI and 1H-MRSI, and confound results from DCE MR imaging.…”