RPGOntology - A Semantic Webized Knowledge Base for Referral Guidelines for Imaging

1. RPGOntology - A Semantic Webized Knowledge Base for Referral Guidelines for Imaging Helen Chen, Ph.D Advanced Clinical Applications Agfa Healthcare

2. Purposes of Radiation Protection Guidelines • To recommend appropriate investigation means • Is this investigation most effective for my prognosis or diagnosis? • Am I benefit from the new research findings and capacity of newly invented modalities? • To reduce wastefulness in radiology practices • Did I have this investigation already or recently? • Am I paying for an expansive study (such as nuclear medicine) while a cheaper investigation means can archive the same goal? • To protect patients from harmful and unnecessary exposure to radiation • Is my body or my unborn child being exposed to radiation which can be or should be avoid? • Am I getting too high dosage of radiation that is not necessary for the study?

3. Guideline Original Format: Tabulated Recommendation

4. Guideline Original Format: Rule-Like Statement • Pregnancy and protection of the foetus • “Irradiation of a foetus should be avoided whenever possible (23-25). This includes situations where pregnancy is not suspected by the woman herself. The prime responsibility for identifying such patients lies with the referring clinician” • “Women of reproductive age presenting for an examination in which the primary beam irradiates directly, or by scatter, the pelvic area (essentially any ionising irradiation between the diaphragm and the keens), or for a procedure involving radioactive isotopes, should be asked whether they are or may be pregnant.” • ……. • Optimizing Investigation • “For investigation of Space-occupying Lesion(SOL), MRI more sensitive for early tumours, in resolving exact position (useful for surgery) and for posterior fossa lesions. CT often sufficient in supratentorial lesions and subdural haematomas. MRI superior in the posterior fossa and for vascular lesions. NM may be useful in tumour viability post-therapy, especially post-radiotherapy” • …….

5. RPGOntology: Taxonomy – Some Examples • InvestigationMethod • MRI • NM • RedCellStudy • NMRenogram • NMSkeletal • PET • SPECT • US • USAorta • USCardiac • USKidneys • USLivers • USCarotids • XR • ……. • CT • ……. • BodyParts • FullBody • Head • Neck • Spine • UpperLimb • LowerLimb • Abdomen • RedCellStudy • NMRenogram • NMSkeletal • PET • SPECT • ClinicalProblem • HeadProblem • NeckProblem • SpineProblem • GeneralSpineProblem • CervicalSpineProblem • ThoracicSpineProblem • LumbarSpineProblem • MusculoskeletalSystemProblem • CardiovascularSystemProblem • ThoracicSystemProblem • GastrointestinalSystemProblem • GastrointestinalTractProblem • GeneralAbdominalProblemsProblem • LiverGallbladderPancreasProblem • UrologicalAdrenalGenitoSystemProblem • ObstetricsGynaecologyProblem • BreastDiseaseProblem • AsymptomaticProblem • SymptomaticProblem • Trauma • HeadTrauma • CervicalSpineTrauma • ThoracicLumbarTrauma • PelvisSacrumTrauma • ……. • ChestTrauma • Cancer • ……. • PaediatricsProblem

6. PRGOntology: Properties – Relations Between Concepts • applyToClinicalProblem • Domain: Investigation • Range: ClinicalProblem • applyToBodyPart • Domain: Investigation • BodyParts • applyToPatientType • Domain:Investigation • Range: PatientType • hasRadiationDose • Domain:InvestigationDetails • Range: RadiationDoes • FunctionalProperty • …………

7. RPGOntology: Example Table M: Paediactrics :m10_1 a :Investigation; :applyToAnatomicParts :head; :applyToClinicalProblem :clinicalProblemM10; :hasInvestigationDetails :InvestigationDetail_1034; :hasRecommendation :Indicated; :applyToPatientType :paediatricPatient; :hasRecommendationGrade :gradeB; rdfs:comment “Back pain is uncommon in children without a cause. Follow-up is needed if infection is suspected."^^xsd:string .

8. Use Cases • Validation of radiological orders • Provide recommendations for a complicated investigation • Offer proofs and explanations of a suggestion or a decision Given facts as patient context • :Ann a patient:Patient; • rpg:hasClinicalProblem rpg:clinicalProblemB8, rpg:mouthFloorCalculus. Get recommendation from reasoning engine by querying RPGOntology • rpg:Ann rpg:isRecommended (rpg:b8_1 rpg:US rpg:indicated). • rpg:Ann rpg:isRecommended (rpg:b8_2 rpg:MRSialography rpg:indicated). • rpg:Ann rpg:isRecommended (rpg:b8_3 rpg:XR rpg:notIndicatedRoutinely).

9. Rules • Sets of rules are derived for different use cases of RPGOntology • Example: rules for recommending investigation using RPGOntology {?A :hasClinicalProblem ?C. ?X rpg:applyToClinicalProblem ?C; rpg:hasRecommendation rpg:Indicated; rpg:hasInvestigation ?Y. ?Y rpg:modalityType ?Z.}=> {?A :isRecommended (?X ?Z rpg:Indicated)}. {?A :hasClinicalProblem ?C, ?V. ?X rpg:applyToClinicalProblem ?C; rpg:hasRecommendation rpg:NotIndicatedRoutinely; rpg:applyOnlyTo ?V; rpg:modality ?Y. ?Y rpg:modalityType ?Z.} => {?A :isRecommended (?X ?Z rpg:NotIndicatedRoutinely)}

10. Beyond the Tables in Guidelines: Connecting Knowledge Bases • RPGOntology becomes one of corpuses of specialized medical knowledge – guidelines and protocols • This knowledgebase is a part of a semantically connected medical knowledgebase, to be used to generate patient-centric care plan for complicated medical investigation and treatment. • When connecting with existing terminology services used in hospital information systems, for example, ICD terminology server and other external reference knowledge bases, the medical expertise is enlarged and enhanced (reuse of knowledge bases). • The health information system built on these connected knowledge bases shall be capable of offering advises based on best practices and guidelines, and also issue flags when a prescribed radiological procedure is not safe for a patient or is not normally the most effective means for the reason for study

11. RPGOntology in Action – An Illustration ICD Terminology Service Request for recommendation or validation Order forms Domain Ontology 1 Reasoning Engines External knowledge Recommendations and Proof Domain Ontology 2 Patient information Guidelines and rules RPG Recommendation Rules Patient Categorization Rules Business Process and Resource Rules Electronic Patient Record System PRGOntology PatientOntology