Computed tomography pulmonary angiography in the diagnosis of acute pulmonary embolism in the emergency department.

This study was undertaken to evaluate the use of computed tomography pulmonary angiography (CTPA) in patients with pulmonary embolism (PE) who were followed in the emergency department (ED). The files and computer records of 850 patients older than 16 years of age who were seen in the Hacettepe University Hospital ED between April 10, 2001, and December 1, 2005, and who required CTPA for PE prediagnosis and/or another diagnosis, were studied retrospectively. PE was identified by CTPA in 9.4% of 416 women and in 5.8% of 434 men. A significant difference (P<.05) was noted in the women and men in whom PE was detected. The mean age of the patients was 58.13+/-17.88 y (range, 16-100 y). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for clinical susceptibility to PE among patients who underwent CTPA were assessed at 95.3%, 48.2%, 13%, and 99.2%, respectively. CTPA was done for different reasons: aortic aneurysm dissection (n=1), cough distinctive diagnosis (n=1), dyspnea distinctive diagnosis (n=6), chest pain distinctive diagnosis (n=3), PE prediagnosis (n=51), and other reasons (n=2). Also, sensitivity, specificity, PPV, and NPV were found to be 95.4%, 16.2%, 14.4%, and 96%, respectively, for D-dimer. CTPA, which is accessible on a 24-h basis in the ED, is a valuable tool for the diagnosis of PE.

Liver volume measurement by spiral CT: an in vitro study.

Liver volume measurement has many clinical and research uses. The purpose of the present study is to evaluate experimentally the accuracy and reproducibility of spiral computed tomography (CT) in measuring liver volume. To determine the accuracy of spiral CT system, nine fresh (non-formalin-fixed) sheep livers were scanned in vitro. The collimation was 7 mm. The CT sections were stored on floppy disks and the images were transferred to the workstation that contained a software for volume measurement. The mean volume is 912+/-497 ml and the actual reference volume is 921+/-527 ml. The correlation between the CT system and actual reference measurement of sheep liver volumes was very strong. The correlation coefficient r was.998 (P<.001) on 7-mm sections. The mean difference between liver volume measurements was 4.95+/-3.23%. As a result, CT scan could be used as a reference noninvasive method for liver volume measurement in clinics.