Hiroshi Fukatsu MD, Presenter: Research collaboration, Toshiba Corporation

Shinji Naganawa MD, Abstract Co-Author: Nothing to Disclose

Masakazu Osada PhD, Abstract Co-Author: Employee, Toshiba Corporation

Kaoru Kurosaki, Abstract Co-Author: Employee, Toshiba Corporation

Takashi Masuzawa MS, Abstract Co-Author: Nothing to Disclose

The purpose of the study was to validate the clinical usefulness of ORION for patients with undetermined pulmonary nodule in serial CT studies to determine the clinical management.

A 64-detector row CT(Acquilion64, Toshiba Inc.) with ORION software was used. The scan position, scan condition and reconstruction parameters fo initial CT was stored within the server in order to reproduce the scan for the follow-up CT. Also the key-image position with the nodule was marked to enable automatic side-by-side display of the key-images of the previous and the present scan. Two staff radiologists were first asked to categorize each nodule as one of the following; malignant, indeterminate and benign showing the initial CT only. Then asked to categorize each nodule as one of the following; a growing nodule:GN, a stable nodule:SN and a shrinking nodule:ShN from the comparison of the two serial CT studies. If the results did not match between the two readers, they discussed to reach the final decision. And the results were correlated with the clinical outcome or the pathological evidence. Twenty-six cases with at least one pulmonary nodule on the initial CT entered the study. The age ranged from 26 to 89 years old including 16 male and 10 female patients. Twenty-one cases had the history of at least one active malignancy.

A total of 46 nodules were detected on the initial CT. Thirteen of them were categorized as malignancy, 23 as indeterminate and 10 as benign for initial CT diagnosis. Twenty of them were categorized as SN, 7 as ShN and 19 as GN. Sixteen of SNs showed no interval change over 12 months after the study, 4 underwent biopsy to reveal 3 granulomas and 1 inflammatory change. One of the ShN received needle biopsy to reveal Cryptococcus granuloma and the other 6 showed further shrinkage on the third follow-up CT. Six of GNs underwent needle or surgical biopsy to reveal malignancy, 13 of the GNs showed further enlargement on the follow-up CT.

Pulmonary nodules detected on CT were better categorized to determine the clinical management using serial comparison of CT findings than using morphological findings of the initial CT only.

Serial comparison of the CT findings may add clinically useful information to the morphological information of the initial CT, which may detect numerous tiny nodules within non-symptomatic subjects.

Fukatsu, H, Naganawa, S, Osada, M, Kurosaki, K, Masuzawa, T, Clinical Usefulness of ORION (Organic Recirculation of Information on Network) for Patients with Undetermined Pulmonary Nodules: Preliminary Results with Pathological or Clinical Validation.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6018712.html