Comparison of image quality characteristics on Silent MR versus conventional MR imaging of brain lesions at 3 Tesla.

OBJECTIVE:: To compare signal- and contrast-to-noise-ratio (SNR, CNR), conspicuity values and subjective image quality characteristics of Silent MRI and conventional MRI in brain disorders at 3 T. METHODS:: 26 patients were prospectively examined with a 3 T MRI. Silent Scan was added to standardized MR protocol. Silenz T1 weighted (Tlw) and Silent T2 weighted (T2w) sequences were compared to standard Tlw and T2w. Analysis was performed quantitatively (SNR, CNR, conspicuity values) and by visual assessment on a 4-point scale with regard to lesion visibility, lesion delineation, grey-white differentiation and diagnostic usefulness. Data were analyzed using Wilcoxon signed-rank and Sign test. p ≤ 0.05 was considered significant. RESULTS:: Silenz Tlw vs Tlw provided decreased SNR, but increased CNR (SNRparenchyma, SNRlesion: p = 0.000, CNRlesion: p = 0.003). Silent T2w vs T2w showed better SNR and CNR values (SNRparenchyma, p = 0.014; SNRlesion, p = 0.005; CNRlesion, p = 0.005). Conspicuity values were not significantly different on Silenz Tlw vs Tlw and Silent T2w vs T2w. The visual assessment revealed Silenz Tlw to be significantly superior to Tlw in terms of grey- white differentiation (p = 0.000), lesion visibility (p = 0.003) and overall diagnostic usefulness (p = 0.001). In terms of Silent T2w vs T2w, there was a significant difference in grey-white differentiation in favour of Silent T2w (p = 0.016). CONCLUSION:: Silent Scan is suitable for 3 T with image quality characteristics comparable to conventional MRI. ADVANCES IN KNOWLEDGE:: Silent Scan has a diagnostic value comparable to conventional MRI, with the advantage of a quiet MR exam improving patient MR experience.

Pattern of Tumour Spread of Common Primary Tumours as Seen on Magnetic Resonance Imaging.

Although some reports with computed tomography and bone scintigraphy are available in the literature, the distinct epidemiologic description of skeletal metastatic pattern of various tumors is still lacking. This study uses a novel approach to identify skeletal metastases from magnetic resonance imaging (MRI) data to describe metastatic pattern in common malignancies. A retrospective analysis of 130 cancer patients (42 lung, 56 breast, 11 prostate cancers; 21 multiple myeloma) with vertebral metastases and without disseminated disease, and whom underwent a whole body 3Tesla MRI investigation (Discovery MR750w), was carried out. Multiple myeloma had the most commonly disseminated metastatic disease (95%) compared to lung (28%), breast (44%) and prostate (71%) cancers. Lung cancer was related to more frequent pedicle involvement compared to breast or prostate cancer (29, 9 and 0%, p < 0.05). Pathologic fracture was mainly associated with multiple myeloma (43%). The prevalence of lung cancer metastases was more frequent in the lumbal spine (81%), as well as particular in C7, D7, D8, D9 and L1, compared to breast cancers. Most differences among tumors were detected in the extravertebral osseous metastatic pattern (p < 0.05). The highest frequency of extravertebral skeletal metastases was present in multiple myeloma (28 to 76%). Brain metastasis was more frequent in lung cancer compared to breast cancers (35% vs. 17%, p < 0.05). Significant differences in the skeletal metastatic pattern among common malignancies were demonstrated with MRI.