The analysis ofVRT reconstruction in CT formation of spatial image of anatomical structures of the lungs was given. Clinical assessment of the technique was carried out for 44 patients with suspected lung lesions not exceeding 10 mm in diameter. The CT analysis of the image was shown to permit new topographic information on anatomical lung structures to be obtained.

OBJECTIVE To describe and apply a method for programmatically calculating central hemodynamic parameters from the data of dynamic contrast X-ray computed tomography (CT). MATERIAL AND METHODS A procedure is proposed to calculate cardiac output (CO) on the basis of the tracer dilution method as a ratio of the injected dose of a contrast agent (Urografin, Shering AG, Austria) to the area under the concentration-time curve derived for one of the cardiac chambers: [see text]. The blood concentration of the agent was estimated from the blood iodine (I) concentration-X-ray density (XD) regression dependence: [XD] = 0.49+22.07 x [I]. Thirty-three patients were studied on a multispiral X-ray Somatom Sensation 4 computed tomograph (Siemens), by injecting 15-20 ml of Urografin. The calculating method was realized as a software package for processing dynamic contrast CT data. RESULTS The proposed method could exactly determine the values of cardiac output: the correlation with the results of the reference technique (Doppler echo measurement) was highly significant (r = 0.95; p < 0.001) in the whole range of values. Moreover, the data on XD could accurately determine the blood concentration of both iodine (I): [XD] = 0.49+22.07 x [I] and gadolinium as a component of the contrast paramagnetic Gd-DTPA for which the solution concentration-XR dependence was as follows: XD 1.2+33.6 x [Gd]. CONCLUSIONS Thus, dynamic spiral CT may be also used for the estimation of cardiac output by the tracer dilution method.