[T2 image contrast evaluation using three dimension sampling perfection with application optimized contrasts using different flip angle evolution (3D-SPACE)].

Purpose: Sampling perfection with application optimized contrasts using different flip angle evolution (3D-SPACE) sequence enables one to decrease specific absorption rate (SAR) by using variable flip angle refocusing pulse. Therefore, it is expected that the contrast obtained with 3D-SPACE sequences is different from that of spin echo (SE) images and turbo spin echo (TSE) images. The purpose of this study was to evaluate the characteristics of the signal intensity and central nervous system (CNS) image contrast in T(2) weighted 3D-SPACE.

[Evaluation of metal artifact in computed radiography].

We know that computed radiography (CR) has many factors to generate artifacts, such as the over / under shoot, aliasing and more. Recently, we encountered an artifact, we call a metal artifact, not attributable to any known factors in clinical images. To elucidate the cause of this artifact, we did some experiments with an in-house phantom.

[Usefulness of intensity-modulated radiation therapy for breast conserving radiation therapy: a three-dimensional treatment planning system comparison of irradiation methods].

Until recently, conservative radiation therapy of breast cancer using a wedge-filter combined with rectangular tangential irradiation was widely carried out. This method of irradiation creates uniform dose distribution in the target, minimizing the radiation dose to the lung. However, this method of irradiation results in many cases in which the amount of dose in the irradiated area differs as a result of the shape and size of the breast.

[Examination of dose verification in intensity modulated radiation therapy (IMRT) treatment planning using averaging dose in chamber volume].

Since the year 2000, our hospital has been equipped with an intensity modulated radiation therapy (IMRT) facility. Before IMRT is administered, the absorbed dose is measured by the ionization chamber to provide verification for the IMRT procedure. In utilizing the current point dose evaluation, large discrepancies have been experienced when the measured dose is compared with the calculated dose.