The value of 3.0T MR high-b-value DWIBS in detecting the cerebral metastases

Comparing the imaging features on the ordinary fa-value and high-b-value DWIBS with that on the enhanced imaging, to explore the value of 3.0T MR high-b-value diffusion weighted imaging with background suppression (DWIBS) in detecting the cerebral metastases. 41 patients with cerebral metastases confirmed by clinically and pathologically were collected. All the patients underwent conventional MRI and contrast-enhanced MRI, and DWIBS used two types b-value: ordinary b-value (b=0, 1000s/mm2) and high-b-value (b=3000s/mm2). Evading cystic necrosis area, the signal intensity (SI), background noise and apparent diffusion coefficient (ADC) value of tumor parenchyma and adjacent normal white matter were measured. The averages of signal to noise ratio (SNR), contrast to noise ratio (CNR) and contrast ratio (CR) were computed from these data. The lesion diagnosis accuracy rate of high-b-value DWIBS was better than that of ordinary b-value. On high-b-value DWIBS sequence, the CNR, CR and SI-lesion/ SI-normal of brain metastasis was significant higher than that of ordinary b-value DWIBS sequence (P<0.05). And the SNR was significant lower than that of ordinary b-value DWIBS sequence (P < 0.05). The CNR, CR of Contrast-enhanced T1WI was significant higher than that of normal brain tissue (P<0.05). The ADC value in High-b-value DWIBS sequence was lower than that in ordinary b-value DWIBS sequence (P < 0.05). Conclusion High-b-value DWIBS sequence showed a great value in detecting cerebral metastases. It was a simple method and could be avoiding potential harm of contrast agent for the human bodies.