Dmitriy Zinovev CSC 594 Final Presentation Project Description

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 paratracheal mass 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 • No adrenal masses are identified. • No new pulmonary parenchymal abnormalities 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.

Summary

Cancer evidence (46 reports) Actual Total 63 3 66 Guessed 10 16 26 Total 73 19 92

Cancer evidence (Co-reference) (23 reports) Actual Total 31 8 39 Guessed 7 8 15 Total 38 16 54

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