[Verification of "IEC 62464-12007": The Evaluation Method of Spatial Resolution in MRI]

Recently, many methods are suggested to evaluate spatial resolution in MRI. However, those techniques are not simple and easy. The International Electrotechnical Commission (IEC) recommends a method to evaluate spatial resolution using a periodic pattern image as IEC 62464-1. IEC 62464-1 prescribes specifications and placement of phantom, and a method of analysis, but these details grounds are not clear. A purpose of this study is to examine the effect in each factor of IEC 62464-1 method and define the characteristics of this method. Nine phantoms with different plate thickness were made including prescribed specifications of IEC 62464-1. Imaging was conducted with changing the placement angle of these phantoms. Also, analysis was carried out in region of interest (ROI) of three different size. As a result, the placement angle of the phantom, measurement error was <1% on a condition prescribed by a method of IEC 62464-1. There was not the effect if the transverse diameter for the longitudinal diameter exceeded 100% fort the size of ROI. In specifications of the phantom, there was not the dependence for the thickness of the plate of the phantom in IEC 62464-1 prescribes.