Compare the Application of Two Different b-Value in Diffusion Weighted Imaged to Signal Differences on 3T MRI

Diffusion-weighted imaging is a specific MRI modality which is important for diagnosing brain infarction. In this study, we aim to find out that by using different b-values in DWI on 3T MRI for better diagnosis of acute or sub acute brain infarction. In 40 Patients with acute or sub acute brain infarction, we use the b-value 1000s/mm² and 1500s/mm² to process diffusion weighted images, and then these images were transferred to the imaging workstation for processing. We analyze the signal intensity and apparent diffusion coefficient (ADC) in the 1) infracted brain, 2) contra lateral normal brain, 3) background area of the infracted brain by circling the region of interest(ROI). It is shown that the higher b-value (1500s/mm² compared to 1000s/mm²) yield lower signal intensity and ADC value in both the normal brain tissue and the infracted area, The signal to noise ratio (SNR) and contrast to noise ratio (CNR) also decrease as the b-value increases, Applying diffusion weighted imaging generated by the 3T MRI machine different b-values(1000s/mm² and 1500s/mm²) to diagnose the brain infraction, we obtain better CNR and SNR by applying b-values 1000s/mm² with statistically significant differences.