Quantification of pleural effusion on CT by simple measurement

Abstract

Aims. To find the simplest method for quantifying pleural effusion volume from CT scans. Methods. Seventy pleural effusions found on chest CT examination in 50 consecutive adult patients with the presence of free pleural effusion were included. The volume of pleural effusion was calculated from a three-dimensional reconstruction of CT scans. Planar measurements were made on CT scans and their two-dimensional reconstructions in the sagittal plane and at three levels on transversal scans. Individual planar measurements were statistically compared with the detected volume of pleural effusion. Regression equations, averaged absolute difference between observed and predicted values and determination coefficients were found for all measurements and their combinations. A tabular expression of the best single planar measurement was created. Results. The most accurate correlation between the volume and a single planar measurement was found in the dimension measured perpendicular to the parietal pleura on transversal scan with the greatest depth of effusion. Conversion of this measurement to the appropriate volume is possible by regression equation: Volume = 0.365 × b 3 -4.529 × b 2 + 159.723 × b -88.377. Conclusion. We devised a simple method of conversion of a single planar measurement on CT scan to the volume of pleural effusion. The tabular expression of our equation can be easily and effectively used in routine practice.

A simple assessment of haemothoraces thickness predicts abundant transfusion: A series of 525 blunt trauma patients

“…Others are more complex, time-consuming and implicate a calculation time (Cumulated-v, Dominant-v) or a CT reconstruction (Cumulated-l and Dominant-l). Although estimated volume formula using mathematical modelisation was strongly correlated with pleural effusion volume, this criterion is intricate and does not seem to be appropriate for an easy and rapid use in clinical practice [24]. Accordingly, the strength of present study was to compare predictive performance of simple criteria versus more complex ones.…”

“…1: the greatest anteroposterior thickness on the transversal plane (t) and the greatest craniocaudal length on the sagittal CT reconstruction (l) [12,[14][15][16]23]. In addition, haemothorax volume (v) was calculated using the following equation described by Hazlinger et al [24]: v ¼ 0:365xt 3 À 4:529xt 2 þ 159:723xt À 88:37:…”

Injured Lung Volume Estimation on Ct Data Using Linear Metrics

“…As the methods for finding the volume of injuries are very complicated and slow, reached insufficient accuracy of calculations, some papers addressed the methods of quantification the volume of lung disease, avoiding organs segmentation. For example, in [4] proposed a method for determining the amount of pleural effusion, having the characteristic form, using simple measurements on the plane and in space, without segmenting pathology. The accuracy of this method varies 4.5-5.1%, depending on the selected measurements.…”

Value of Computed Tomography of the Chest in Subjects With ARDS: A Retrospective Observational Study

“…Pleural effusions were measured by assessing the maximum perpendicular diameter to the parietal pleura at the greatest depth on axial CT images. 17 A pleural effusion was categorized as small if its diameter was Ͻ2 cm, medium size if its diameter was Ն2 cm but Ͻ5 cm, and large if its diameter was Ն5 cm. Pneumothorax was graded into 3 categories using a modified CT classification by assessing the anteroposterior diameter on axial CT images and the craniocaudal diameter 18 : (1) small if its anteroposterior diameter on the axial plane was Ͻ1 cm and its craniocaudal diameter was Ͻ4 cm, (2) medium if its anteroposterior diameter was Ն1 cm but did not extend across the midcoronal line and its craniocaudal diameter was Ͻ4 cm, and (3) large if its anteroposterior diameter extended across the mid-coronal line or its craniocaudal diameter was Ն4 cm.…”