The ‘3D PACS Study Group’ was established in December 2008 for promoting research and improving knowledge on image processing technologies and clinical applications. It is targeted at medical science technicians who use 3D PACS products and their peripheral equipment as well as at contributing to medical sites.

This article features the details of a lecture given at the Seventh Session of the 3D PACS Study Group, which was held in Nagoya City in December 2014.

An effective dose was sometimes detected by the personal dosimeter (glass badge) worn by the radiological technologist in an ultrasound examination. The maximum effective dose detected was 0.2 mSv per month and 1.1 mSv per year. An investigation suggested that the source of the radiation exposure was the administration of radiopharmaceuticals before ultrasound examination. We evaluated 921 cases in which radiopharmaceuticals had been administered before an ultrasound examination between April 2010 and March 2012. The effective dose was higher when more ultrasound examinations were carried out subsequent to the administration of radiopharmaceuticals. The shielding ratio for a 4-mm lead sheet was approximately 95% for Tc-99m and approximately 79% for I-131, suggesting that a lead sheet (masking shield) may be effective.

Prostate cancer has traditionally been treated with surgery and hormone therapy, but radiotherapy has attracted attention in recent years as an additional treatment option. A number of studies have been conducted on treatment by using external irradiation, and highly precise radiation therapy such as three-dimensional conformal radiotherapy and intensity-modulated radiotherapy has enabled safe and effective treatment. Meanwhile, the reality is that no examination of the bladder volume is conducted during treatment planning. At our institution, 53 prostate cancer patients treated with IMRT were designated as the subjects of a study in which we retrospectively analyzed the results of DVH and urination frequency to determine the optimal bladder volume. The results indicated that the optimal bladder volume was 200 mL or larger.

Q-Space Imaging (QSI) is widely used to evaluate non-Gaussian, restricted diffusional changes of water molecules. We scanned the brains of volunteers to evaluate the optimal settings of Motion Probing Gradient (MPG) settings in clinical use. The settings of MPG direction were MPG1, MPG2, MPG3, MPG6, and MPG15. We evaluated analysis values of the Probability Density Function (PDF) of the cerebrospinal fluid (CSF), corpus callosum ampulla (white matter), posterior limb of internal capsule (white matter), and thalamus (gray matter). In the MPG3 or more axes, the comparable results were obtained at all measurement points. In addition, in the MPG2, it was equal to results of MPG15 by a setting direction. In conclusion, in the clinical use of QSI, the MPG3 or more settings are appropriate.

An anonymous questionnaire survey consisting of 8 questions was conducted to 35 radiological technologists in our institution regarding their feelings and awareness about autopsy imaging (Ai). Among them, 30 subjects (85%) responded, with approximately 60% of them indicating an interest in Ai, mainly for its potential contribution to society. And 90% of the respondents answered an absence of negative feelings associated with the imaging of unnaturally deceased bodies, as a matter of their routine work. However, only 30% of the respondents were aware of two recent Japanese laws regarding death-cause detection, while 70% of the respondents had awareness of a model project for pediatric Ai, suggesting insufficient knowledge of the background and reasoning behind the needs of Ai. Our survey results were compared with two other previously-published surveys. Our comparative investigation suggests necessity of more Ai-related education in training institutes, greater distribution of relevant information by the Japan Association of Radiological Technologists, and the sharing of experiences among hospital staffs, all of which will help meet the needs and social demands of Ai.