Construction of mammographic examination process ontology using bottom-up hierarchical task analysis.

Describing complex mammography examination processes is important for improving the quality of mammograms. It is often difficult for experienced radiologic technologists to explain the process because their techniques depend on their experience and intuition. In our previous study, we analyzed the process using a new bottom-up hierarchical task analysis and identified key components of the process. Leveraging the results of the previous study, the purpose of this study was to construct a mammographic examination process ontology to formally describe the relationships between the process and image evaluation criteria to improve the quality of mammograms. First, we identified and created root classes: task, plan, and clinical image evaluation (CIE). Second, we described an "is-a" relation referring to the result of the previous study and the structure of the CIE. Third, the procedural steps in the ontology were described using the new properties: "isPerformedBefore," "isPerformedAfter," and "isPerformedAfterIfNecessary." Finally, the relationships between tasks and CIEs were described using the "isAffectedBy" property to represent the influence of the process on image quality. In total, there were 219 classes in the ontology. By introducing new properties related to the process flow, a sophisticated mammography examination process could be visualized. In relationships between tasks and CIEs, it became clear that the tasks affecting the evaluation criteria related to positioning were greater in number than those for image quality. We developed a mammographic examination process ontology that makes knowledge explicit for a comprehensive mammography process. Our research will support education and help promote knowledge sharing about mammography examination expertise.

Constructing mammography examination process ontology using affinity diagram and hierarchical task analysis.

Mammography is complex and difficult for beginner radiologic technologists (RTs) because knowledge and technical skills rely on one's experience, and it is often difficult for experienced RTs to verbally explain the process to co-workers or beginners. The purpose of this study was to construct a mammography examination process ontology for knowledge sharing among RTs and propose a new ontology construction method using an affinity diagram (AD) and hierarchical task analysis (HTA). First, tasks collected by brainstorming were clustered and connected using the AD. Subsequently, a hierarchical structure was constructed based on the clusters and relations determined in the AD. Finally, a mammography process ontology was determined based on the relations noted in the AD and HTA. As a result, the ontology contained 203 classes and 669 relations.

[Pilot study of domain-specific terminology adaptation for morphological analysis: research on unknown terms in national examination documents of radiological technologists].

Although large medical texts are stored in electronic format, they are seldom reused because of the difficulty of processing narrative texts by computer. Morphological analysis is a key technology for extracting medical terms correctly and automatically. This process parses a sentence into its smallest unit, the morpheme. Phrases consisting of two or more technical terms, however, cause morphological analysis software to fail in parsing the sentence and output unprocessed terms as "unknown words." The purpose of this study was to reduce the number of unknown words in medical narrative text processing. The results of parsing the text with additional dictionaries were compared with the analysis of the number of unknown words in the national examination for radiologists. The ratio of unknown words was reduced 1.0% to 0.36% by adding terminologies of radiological technology, MeSH, and ICD-10 labels. The terminology of radiological technology was the most effective resource, being reduced by 0.62%. This result clearly showed the necessity of additional dictionary selection and trends in unknown words. The potential for this investigation is to make available a large body of clinical information that would otherwise be inaccessible for applications other than manual health care review by personnel.

Vastus lateralis oxygenation and blood volume measured by near-infrared spectroscopy during whole body vibration.

The purpose of this study was to investigate the effects of whole body vibration (WBV) on oxygenation of vastus lateralis muscle during squatting exercise. Eighteen male subjects [mean age, 27.3 +/- 6.0 (SD) years; mean height, 171.8 +/- 4.9 cm; mean weight, 64.4 +/- 6.1 kg] performed squatting exercise on a vibration platform for 3 min with and without vibration, and changes in oxygenation of the vastus lateralis muscle were determined by near-infrared spectroscopy. The muscle oxygenation levels and total haemoglobin and myoglobin levels (total Hb/Mb) decreased during squatting exercise with and without vibration. After exercise, the muscle oxygenation level and total Hb/Mb rapidly increased from the minimum value during exercise and remained constant for latter 10 min. The muscle oxygenation levels with vibration from 90 to 180 s after the start of squatting exercise were significantly lower than those without vibration. Total Hb/Mb with vibration from 90 s after the squatting exercise to 540 s were significantly higher than those without vibration. This study demonstrated that WBV exercise affects the oxygenation level of vastus lateralis muscle and reduces muscle oxygenation level compared to that with no WBV. Therefore, WBV exercise may be an efficient training stimulus for muscle deoxygenation.