Tsukasa Doi

Akio Ogura7
Mitsuyuki Takahashi3
7Akio Ogura
3Mitsuyuki Takahashi
Learn More
When measuring the signal-to-noise ratio (SNR) of an image the used parallel magnetic resonance imaging, it was confirmed that there was a problem in the application of past SNR measurement. With the method of measuring the noise from the background signal, SNR with parallel imaging was higher than that without parallel imaging. In the subtraction method(More)
The apparent diffusion coefficient (ADC) values are calculated by using signal intensity in diffusion-weighted images (DWIs) with two or more different b-value. Therefore, the signal to noise ratio (SNR) of DWI with higher b-value may have a big influence on the measured ADC value. We examined the influence of the imaging parameters on the calculated ADC(More)
In magnetic resonance imaging (MRI) examination of the patients with the cochlear implant, only limited data have a mention for safety information in the instruction manual supplied by the manufacturers. Therefore, imaging operators require more detailed safety information for implant device. We conducted detailed examination about displacement force,(More)
OBJECTIVE The aim of the study was to investigate the causes of apparent diffusion coefficient (ADC) measurement errors and to determine the optimal scanning parameters that are independent of the field strength and vendors of the magnetic resonance (MR) system. MATERIALS AND METHODS Brain MR images of 10 healthy volunteers were scanned using 6 MR(More)
In many clinical imaging procedures using arrays of multiple receiver coils, a uniform sensitivity process is performed using the sensitivity distribution from the body coil. This causes the noise to be uneven, and background noise cannot be used when measuring the signal-to-noise ratio (SNR). The SNR of clinical images with sensitivity correction using(More)
The definitional equation of the distortion of echo planar imaging(EPI)was examined. We compared measured values with calculated values by using the definitional equation of the chemical shift of the EPI method that first composed the diffusion-weighted image, and examined the possibility of applying it to the distortion. The results showed that the(More)
We evaluated the fitting scan technique for CE-3dMRDSA, and found common ground that determines spatial resolution and time resolution (slab thickness and partition number). We also examined the relation between appearance and time resolution (volume of contrast medium and injection speed). To obtain good image contrast, the volume of contrast medium needs(More)
  • 1