Jin Mo Goo MD, Presenter: Nothing to Disclose

Kyongtae Tyler Bae, Abstract Co-Author: Nothing to Disclose

Trongtum Tongdee, Abstract Co-Author: Nothing to Disclose

Ranista Tongdee MD, Abstract Co-Author: Nothing to Disclose

Kwangjae Yeo, Abstract Co-Author: Nothing to Disclose

Accurate and reliable nodule volume measurement requires the acquisition of appropriate 3D imaging data. There are many scan and reconstruction parameters affecting the quantification of nodule volume. The purpose of this study is to evaluate the impact of various reconstruction parameters and nodule segmentation thresholds on volumetric measurement of lung nodules with multi-detector row CT.

Synthetic lung nodules of four different sizes (3.2, 4.8, 6.4, and 12.7 mm in diameter) were scanned with multi-detector row CT. Images were reconstructed at various combinations of section thicknesses (0.75-, 1-, 2-, 3-, and 5-mm), fields of view (FOV) (30-, 20-, and 10-cm), and reconstruction intervals (0.5-, 1-, 2-mm). The nodules were segmented from the simulated background lung region using four different segmentation thresholds (-300, -400, -500, and -600 HU), and their volumes were estimated and compared with a gold standard (i.e., measurements by the fluid displacement method) by computing absolute percentage error (APE). The effects of image reconstruction parameters, threshold, and nodule diameter on APE were evaluated by means of correlation and regression analyses.

Section thickness, threshold, and nodule diameter were significantly correlated with APE and significant determinants of APE (P .05).

For accurate measurement of lung nodule volume or volume change, it is critical to select a section thickness and/or segmentation threshold appropriate for the size of a nodule.

Goo, J, Bae, K, Tongdee, T, Tongdee, R, Yeo, K, Volumetric Measurement of Lung Nodules with Multi-Detector Row CT: Impact of Various Image Reconstruction Parameters and Segmentation Thresholds on Measurement Accuracy.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4406520.html