We propose a new method of converting thin-slice CT images to thick-slice images without image raw data. Slice sensitivity profiles (SSPs) were measured in the thin- and thick-slice settings. The spatial frequency property in the slice direction of the thin-slice images was converted to that of thick-slice images, based on the spatial frequency response calculated using the each SSP. In this study, we used CT images of seven subjects obtained in lung cancer screening, with a 4-slice scanner. The images were reconstructed with slice thicknesses of 5 and 8 mm, and the SSPs were measured in the scanner for the two slice settings, respectively. We calculated 8 mm-thick images from the 5 mm-thick images by the proposed method, and compared them with the actual 8 mm-thick images; this difference was evaluated by the root mean square error (RMSE). The mean value of RMSEs for seven subjects was approximately 6.0 Hounsfield Unit (HU). In addition, we obtained 8 mm-thick images by a conventional technique of weighted average from the 5 mm-thick images; the mean value of RMSEs was approximately 10.0 HU. The proposed method was demonstrated to be effective for converting thin-slice images to thick-slice images accurately.

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“Educational grants for cancer professionals” began in 2007 and 23 medical physics graduate programs were established. We, the Educational Committee of the Japanese Society of Medical Physics (JSMP) conducted a nationwide survey of medical physics graduate programs to learn the state of each one and to find out any problems.
We sent surveys to 23 programs in February 2009 and received replies from all of them by April 2009.
There were 21 doctorial course students and 65 master course students in all over Japan. There were 31professors, 17 associate professors and 27 assistant professors of medical physics. Only two faculties regarded the number of staff members as sufficient. Twenty-four faculties recognized that the variety of specialists in their faculty was insufficient. Other insufficient points were identified as: educational cost in 14, educational facilities in 13, collaborations with other departments in 7, collaborations with other medical physics programs in 8, and recognition by other university staff members in 7.
The medical physics graduate courses have just started and are not sufficient in many points. The JSMP educational committee is organizing a graduate program subcommittee to support these courses by providing a place for discussing and finding solutions to the problems.

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