Semantic representation of reported measurements in radiology.

BACKGROUND: In radiology, a vast amount of diverse data is generated, and unstructured reporting is standard. Hence, much useful information is trapped in free-text form, and often lost in translation and transmission. One relevant source of free-text data consists of reports covering the assessment of changes in tumor burden, which are needed for the evaluation of cancer treatment success. Any change of lesion size is a critical factor in follow-up examinations. It is difficult to retrieve specific information from unstructured reports and to compare them over time. Therefore, a prototype was implemented that demonstrates the structured representation of findings, allowing selective review in consecutive examinations and thus more efficient comparison over time. METHODS: We developed a semantic Model for Clinical Information (MCI) based on existing ontologies from the Open Biological and Biomedical Ontologies (OBO) library. MCI is used for the integrated representation of measured image findings and medical knowledge about the normal size of anatomical entities. An integrated view of the radiology findings is realized by a prototype implementation of a ReportViewer. Further, RECIST (Response Evaluation Criteria In Solid Tumors) guidelines are implemented by SPARQL queries on MCI. The evaluation is based on two data sets of German radiology reports: An oncologic data set consisting of 2584 reports on 377 lymphoma patients and a mixed data set consisting of 6007 reports on diverse medical and surgical patients. All measurement findings were automatically classified as abnormal/normal using formalized medical background knowledge, i.e., knowledge that has been encoded into an ontology. A radiologist evaluated 813 classifications as correct or incorrect. All unclassified findings were evaluated as incorrect. RESULTS: The proposed approach allows the automatic classification of findings with an accuracy of 96.4 % for oncologic reports and 92.9 % for mixed reports. The ReportViewer permits efficient comparison of measured findings from consecutive examinations. The implementation of RECIST guidelines with SPARQL enhances the quality of the selection and comparison of target lesions as well as the corresponding treatment response evaluation. CONCLUSIONS: The developed MCI enables an accurate integrated representation of reported measurements and medical knowledge. Thus, measurements can be automatically classified and integrated in different decision processes. The structured representation is suitable for improved integration of clinical findings during decision-making. The proposed ReportViewer provides a longitudinal overview of the measurements.

User needs and requirements analysis for big data healthcare applications.

The realization of big data applications that allow improving the quality and efficiency of healthcare care delivery is challenging. In order to take advantage of the promising opportunities of big data technologies, a clear understanding of user needs and requirements of the various stakeholders of healthcare, such as patients, clinicians and physicians, healthcare provider, payors, pharmaceutical industry, medical product suppliers and government, is needed. Our study is based on internet, literature and market study research as well as on semi-structured interviews with major stakeholder groups of healthcare delivery settings. The analysis shows that big data technologies could be used to align the opposing user needs of improved quality with improved efficiency of care. However, this requires the integrated view of various heterogeneous data sources, legal frameworks for data sharing and incentives that foster collaboration.

Ontology based clinical query extraction.

Knowledge about human anatomy, radiology and diseases that is essential for medical images can be acquired from medical ontology terms and relations. These can then be analyzed using domain corpora to observe statistically most relevant term-relation-term patterns. We argue that such patterns are the basis for more complex clinical search queries and describe our approach for deriving them. These patterns can then be used to support the knowledge elicitation process between the domain expert and the knowledge engineer by providing a common vocabulary for the communication.