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Dmitriy Zinovev. CSC 594 Final Presentation. Project Description. Retrieve current information related to lung abnormalities from the free-text radiological reports. Finding. Location. Size.
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Dmitriy Zinovev CSC 594 Final Presentation
Project Description • Retrieve current information related to lung abnormalities from the free-text radiological reports. Finding Location Size Within the anterior segment of the right upper lobe, there is a 1.2 x 1.7 cm peripheral lesion which comes close to the pleural surface.
Issues • Locating findings • Distinguishing recent findings from past ones • Resolving co-references • Taking negation into account • Determining whether a change has been noticed since last exam
Locating findings • …decrease in size of a small spiculated mass in the anterior… • …nodular opacity is seen… • …a rounded nodule in the right lower lobe… • …tiny 2 mm left upper lobe micronodule… • …is a bilobed focus, measuring 11 x 9 mm… • Create a dictionary of terms • Search “findings” portion of the report for the matches
Locating findings • Extract location & size information associated with finding. • Search for location terms within the sentence using designated “location” dictionary. • Search for size within the sentence using pattern matching. [0-9]+ ,? [0-9]+ (X? [0-9]+ ,? [0-9]+)? _? (c|m)m • Use grammar parser to determine whether the extracted info refers to the finding
Distinguishing recent findings from past ones On 6/9/05, this right paratrachealmass measured 5.6 x 6.3 cm and currently measures 5.4 x 5.6 cm (series 2, image 18). • Use grammar parses to check whether the verb associated with the subject has past tense
Resolving co-references • In the left upper lobe, a triangular nodule is present on series 5 image 5. It also was present on the study from 10/17/02. It appears slightly more triangular in shape on the current study but has not changed significantly between exams.
Resolving co-references • The majority of the mass is of low attenuation centrally, with a thin rim of tissue present around the periphery. It currently measures 42 x 37 mm, decreased from 49 mm on the previous study.
Resolving co-references • If information of interest has not been found in the same sentence where finding was located, check if the subject of next matches with one of keywords. (This|It)
Taking negation into account • Noadrenal masses are identified. • No new pulmonary parenchymalabnormalities are identified • There are no pulmonary nodules or masses • There are no focal areas of pulmonary consolidation
Determining whether a change has been noticed since last exam • A 4 mm left lower lobe micronodule is again seen, which is unchanged in size and appearance • Both were present on a remote CT dating back to 10/17/02 and are stable.
Accuracy • Percentage of correctly classified findings identified as current: • 80.82%
Future work • Obtain more data • Build more sophisticated co-reference resolution tool • Generalize the rest of techniques