Wenli Cai PhD, Abstract Co-Author: Nothing to Disclose

Hiroyuki Yoshida PhD, Abstract Co-Author: Patent holder, Hologic, Inc Patent holder, Median Technologies Consultant, AZE Col, Ltd

June-Goo Lee, Presenter: Nothing to Disclose

Karim Fikry, Abstract Co-Author: Nothing to Disclose

Marc de Moya MD, Abstract Co-Author: Nothing to Disclose

Robert A. Novelline MD, Abstract Co-Author: Nothing to Disclose

The purpose of this study was to answer two questions: (1) Whether the management of traumatic pneumothorax (PTX), i.e., the decision making about chest tube drainage (CTD), needs accurate volumetry, and (2) whether the accurate volume of PTX plays a more important role than other clinical parameters in the management of traumatic PTX.

Sixty consecutive chest trauma patients (23 women and 37 men, mean age 42±21 years) with 71 diagnosed cases of PTX (44 left and 27 right) were collected for the study. Of these, 21 cases were treated by CTD. In addition to the volume of PTX, a total of 14 clinical parameters were collected as parameters for decision making about CTD. For determination of the critical role of volume of PTX in the decision making about CTD, four studies were designed and their importance metrics (IM) maps were created: (I) all 14 parameters, (II) 13 parameters with removal of volume, (III) 11 parameters with removal of all size parameters, and (IV) 11 parameters plus the three-scale size parameter. The IM map was calculated from the top 100 parameter combinations with the best performance, which were selected by a computer simulation of decision making about CTD.

The average performance, defined as the average area under the receiver operating characteristic (ROC) curve (Az), of the top 100 best parameter combinations for the four studies were 0.905 (95% CI: 0.904 - 0.906), 0.849 (95% CI: 0.847- 0.851), 0.732 (95% CI: 0.725 - 0.738), and 0.856 (95% CI: 0.855 - 0.859). Pairwise F-tests demonstrated that the performance in the four studies was statistically significantly different, with the p-values <0.001, except for Study II and Study IV with a p-value of 0.324. Volume was the dominant parameter in decision making about CTD, with an IM value of 1.00 in Study I. In Study II, linear size became the dominant parameter, with an IM value of 0.85. In Study III, there was no dominant parameter. In Study IV, the three-scale size parameter became the dominant parameter, with an IM value of 1.00.

The results showed that the accurate volumetry of PTX is indispensable for an effective management of traumatic PTX, and the volume of PTX plays the critical role in the decision making about CTD.

This study provides scientific evidence for physicians in understanding and thus establishing a size-based clinical guideline for the effective management of traumatic PTX.

Cai, W, Yoshida, H, Lee, J, Fikry, K, de Moya, M, Novelline, R, Accurate Volumetric Size of Pneumothoraces in MDCT Images Is the Critical Parameter for Decision-making about Chest Tube Drainage in the Management of Traumatic Pneumothorax.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9011014.html