ABSTRACT
<p><b>OBJECTIVE</b>To assess the diagnostic value of dual energy CT for lymph node metastasis in patients with non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Forty NSCLC patients, including 15 cases of squamous cell carcinoma and 25 cases of adenocarcinoma, underwent dual energy CT examination in pre-contrast and venous phase contrast scans, then the CT attenuation value of the lung cancer lesions and 85 mediastinal enlarged lymph nodes (the short diameter ≥ 5 mm, 53 metastatic and 32 non-metastatic) were measured at different energy levels (40-190 keV, spacing 10 keV) in venous phase contrast. CT spectral curves of the lung cancer lesions, hilus pulmonis and mediastinal enlarged lymph nodes were produced automatically, through comparing their CT spectral curves slope to judge whether or not the lymph nodes were metastatic. Receiver operating characteristic (ROC) curve was used to evaluate the efficiency of CT spectral curve in diagnosis of lymph node metastasis.</p><p><b>RESULTS</b>The CT spectral curves slopes of the lung cancer, metastatic lymph nodes and non-metastatic lymph nodes were 1.10±0.11, 1.08±0.07 and 1.54±0.17, respectively. There was no significant difference in curve slope between metastatic lymph nodes and lung cancer (=-1.32,>0.05); while there was significant difference between non-metastatic lymph nodes and lung cancer (=-2.58,<0.05). The CT spectral curve slope ratios of metastatic and non-metastatic lymph nodes to lung cancer were 0.98±0.05 and 1.40±0.12, respectively (=-2.86,<0.05). ROC curve showed that taking CT spectral curve slope ratio of 1.15 as cut-off value for the diagnosis of metastatic lymph nodes, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 81.1%, 87.5%, 91.5%, 73.7% and 83.5%, respectively.</p><p><b>CONCLUSIONS</b>Dual energy CT is of value in improving the diagnostic accuracy of lymph node metastasis in NSCLC patients before treatment.</p>
ABSTRACT
Objective To evaluate the accuracy of a novel echocardiographic three-dimensional automated software for the assessment of the aortic root in candidates for transcatheter aortic valve replacement(TAVR).Methods Four patterns(Lax,Lax-Res,Sax,Sax-Res) of 3D-TEE imaging of aortic root were gotten preoperatively in 18 patients with severe tricuspid aortic stenosis who were referred to our center for TAVR.The specialized 3D-TEE reconstruction software,eSie Valves,then automatically configured a geometric model of the aortic root from the images obtained by 3D-TEE and performed a quantitative analysis of these structures:the minimal diameter(Dmin),maximal diameter(Dmax),area and perimeter(Peri) of aortic annulus,height of the ostia of the left/right coronary artery above the aortic annulus(LOH/ROH).The echo dimensions were compared with the MDCT measurements.Results No statistically significant difference were found in above parameters between the ZOOM pattern (Sax-Res and Lax-Res) and CT measurements(all P>0.05).Lax-Res pattern measurements had good correlation with MDCT,with r valves of 0.81,0.77,0.89,0.84 for Lax-Res-Dmin,Lax-Res-Dmax,Lax-Res-Area,Lax-Res-Peri,respectively(all P<0.05).3D-TEE LOH/ROH had poor correlation with MDCT LOH/ROH (all r<0.7).Conclusions The new automatic 3D-TEE software allows modelling and quantifying the aortic annulus dimensions from 3D-TEE data in patients with tricuspid aortic valves,and Lax-Res pattern is recommended.Quantified assessment of LOH/ROH is not ideal and needs to be improved.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the value of preoperative assessment on transcatheter aortic valve implantation (TAVI) procedure with high-pitch dual-source computed tomography angiography (CTA).</p><p><b>METHODS</b>Seventeen consecutive patients with severe symptomatic aortic stenosis underwent TAVI in our department from December 2012 to December 2013 were examined by 128-slice prospective ECG-triggered high-pitch spiral CTA and the clinical data were analyzed. Aortic annulus, sinus of Valsalva, sinotubular junction, ascending aorta and native leaflet to coronary ostium length were measured. Peripheral vascular access was evaluated. Then the patients were assessed on the suitability for TAVI procedure and prosthetic valve sizes.</p><p><b>RESULTS</b>Mean diameter of the aortic annulus was (25.7 ± 2.0) mm, perimeter mean diameter was (26.4 ± 2.0) mm, area mean diameter was (25.4 ± 1.9) mm. Mean diameter of sinus of Valsalva was (34.0 ± 3.8) mm. Mean diameter of sinotubular junction was (30.5 ± 3.2) mm. Mean diameter of ascending aorta was (37.8 ± 2.8) mm. The length from native leaflet to left coronary ostium was (14.0 ± 2.0) mm, and the length from native leaflet to right coronary ostium was (15.9 ± 3.6) mm. Mean diameter of left iliac arteries was (7.5 ± 1.4) mm. Mean diameter of right iliac arteries was (7.4 ± 1.2) mm. Mean diameter of left femoral arteries was (7.4 ± 1.2) mm. Mean diameter of right femoral arteries was (7.3 ± 1.3) mm. One patient was considered ineligible for TAVI because of large aortic annulus diameter. Three patients died prior to TAVI. Two patients refused to undergo TAVI. Eleven patients underwent TAVI, 26# prosthetic valve was implanted in 1 patient, 29# prosthetic valve implanted in 6 patients, 31# prosthetic valve implanted in 4 patients. Prosthetic valve implantation was successful in 9 patients and only mild or trace perivalvular leakage was observed in these patients. Moderate perivalvular leakage were observed in 2 patients because of the location of implantation was too low, and perivalvular leakage was significantly reduced after re-implantation with same size prosthetic valve at a higher location.</p><p><b>CONCLUSIONS</b>CTA can be used to evaluate the aortic root anatomy and vascular access, and help to choose the right size of prosthetic valve. CTA has an important practical value in preoperative screening of TAVI procedure.</p>