Clinical Application Research Of Double Energy Lung Perfusion Imaging With DSCT In Pulmonary Embolism

objective:1.We adopt two Scanning modes, Dual source CT dual energy CT pumlmonary angiography and conventional CT pumlmonary angiography to analyze the pulmonary embolism,to investigate the relationship between the positions and types of the pulmonary embolism and the relationship between dual energy perfusion imaging (DEPI), so as to find further exploration of the relationship between form and function.2.By comparing DECTPA mediastinal window and lung window images with dual energy perfusion imaging (DEPI), diagnostic effectiveness of DECTPA were evaluated.3.To evaluate the significance of effectiveness before and after the treatment of the patient.4.To evaluate the PE clinical diagnosis significance of DECTPA double period in scans on scanning of the different choices.5.To discuss the correlation between PE embolism index and the arterial blood gas analysis indexes, and correlation between PE embolism index and the right heart function indexes of the PE patients.6.To discuss the differences of DECTPA and CTPA in scanning methods, image quality, and radiation dose.7.To assess the feasibility of CT scan with low radiation dose using (Care Dose 4D)Materials and methods:1.From November 2009 to March 2011 in the First Affiliated Hospital of Kunming Medical College,200 patients who accepted by contrast chest scan, who were suspected of pulmonary embolism in clinical were available, were selected. In it, continuous line DECTPA imaging 100 cases, and continuous line CTPA imaging 100 cases. We compare and analyse the relationship between the clinical and imaging PE performance, the relationship between the embolism position and type of two groups of scanning mode.2.Apply DSCT Lung PBV software to further analysis 41 cases of DECTPA detected PE patients. Set mediastinum window pulmonary enhanced image diagnosis for reference standard, to evaluate (DEPI) image effectiveness of diagnosis PE. Pulmonary perfusion image with pulmonary window image diagnosis lung perfusion Experimental data analysis.3.8 cases of DECTPA group in the diagnosis of PE patients, scanning by DECTPA before and after treatment, were compared numbers of the embolism with changes in lung perfusion before and after the treatment. The curative effect and prognosis were evaluated.4.11 cases of DECTPA group in the diagnosis of PE patients were checked by the double period phase scanning of the lung perfusion, with better scanning phase.5.90 cases of both DECTPA and CTPA group in two scanning modes in the diagnosis of PE patients were measured esch index of the right heart function and were calculated the PE embolism index. We analyse the correlation between right heart function of each index and PE embolism index.6.15 cases of both DECTPA and CTPA group in two scanning modes in the diagnosis of PE patients, with arterial blood gas analysis indicators and without the conscription examination based cardiopulmonary diseases, were calculated the PE embolism index. We discuss the correlation between each arterial blood gas index and PE embolism index.7.We select each 25 cases from each group to find out the differences in volume computed tomography dose index (CTDI), dose length product (DLP) and effective dose (ED), to measure the enhanced CT value of pulmonary artery and back noise,and to calculate signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), then to evaluate the image qualities of two groups according to quantitative and qualitative analysis.8.The DECTPA 50 patients are divided into two groups based on Care Dose4D scanning techniques, which 25 cases in (Care Dose4D ON) group and 25 cases in (Care Dose4D OFF) group. We evaluate image qualities of pulmonary artery obtained by two scanning methods, compare differences of the radiate doses, and compare the differences in volume computed tomography dose index (CTDI), dose length product (DLP) and effective dose (ED).Results:1.90 PE patients were found out of 200 patients in DECTPA and CTPA two scanning modes, with 51 PE cases in DECTPA and 39 PE cases in CTPA. 365 pulmonary artery embolism branches were found in 90 cases of PE patients, which central type 115 cases, occluded type 147 cases, obtuse angle attach wall type 45 cases, acute angle attach wall 28 cases, irregular and saddle type each 15 cases, right pulmonary main artery 28 cases, right pulmonary upper leaf artery 51 cases, right pulmonary middle leaf artery 43 of cases, right pulmonary lower leaf artery 92 cases, left pulmonary main artery 24 of cases, left pulmonary upper leaf artery 52 of cases, left pulmonary lower leaf artery 75 cases. Compare clinical data of different index between two groups of PE group and non-PE group, with P<0.05 difference as statistical significance, it is concluded that PE and the Non-PE group in the chest pain, cough, haemoptysis and difficulty breathing major clinical symptoms and D-dimers positive index between the two groups in the difference was no statistical significance, in lower limb vein thrombosis, the difference between the two groups have statistical significance.2.We analyse 41 PE patients from DECTPA scanning group, including PE embolization position, degree, time, type. We compare the relationship between them and lung perfusion change after embolization:if the embolism occurred in pulmonary trunk, complete type can be seen all of pulmonary or lobectomy perfusion defection, attach wall type or center type can be seen lobectomy or section perfusion defection mostly; if the embolism occurred in lung section, complete lobectomy can be seen lobectomy or section type defection mostly, enclosed wall type or center type can be seen lung section, the section perfusion defectoion or no perfusion defection mostly; if the embolism occurred in section, all the types can be seen section perfusion defection or no perfusion defection.3.In 41 patients,63 PE cases occurred in lobectomy. Set mediastinum window pulmonary contrast image PE diagnosis for reference standard, apply ROC curves images and pulmonary lung perfusion of window of its image diagnosis PE experimental data analysis, the results showed that:mediastinum window pulmonary enhanced image and perfusion image has similar results to detect PE, while perfusion image and lung window image have not comparable results to detect PE.4.8 cases of PE patients in DECTPA scan group, comparing and analysing PE position and lung perfusion defect situation, were found that each index has statistical significance (P<0.05) before and after the treatment.5.11 PE cases were scanned by DECTPA double period scanning group. The result is that on the right-middle, right-lower, and left- lower lung perfusion have statistical significance.6.DECTPA group and CTPA group have detected 90 PE patients.The correlation between right ventricular maximum horizontal diameter, the right/left ventricular biggest diameter ratio and the Qanadli embolism index have statistical significance (P<0.05).7.15 PE patients, with arterial blood gas analysis indicators and without the conscription examination based cardiopulmonary diseases in clinical:the correlation between PaCO2, SaO2 and Qanadli embolism index have statistical significance(P<0.05).8.25 cases from both DECTPA group and CTPA group, CTDIVOL, DLP, ED between groups have no statistical significance (P>0.05), two kinds of scanning radiation dose have no statistical significance; image quality of two groups have no statistical significance (P>0.05) on background noise, SNR and CNR; the two groups have different degrees of pulmonary arteriosclerosis.9.25 cases from Care Dose4D ON group and Care Dose4D OFF group separately in DECTPA scanning group, CTDIVOL between groups, DLP, ED have statistical significance (P<0.05), Care Dose4D ON radiation dose below Dose4D OFF group, reduce with about 50%; Two groups of image quality have no statistical significance (P>0.05).Conclusion:1.There is no difference between PE and Non-PE group in major clinical symptoms such as the chest pain, cough, haemoptysis and difficulty breathing and D-dimers positive indexes. The detection should mainly depend on imaging diagnosis.2.The right side is more than the left side of pulmonary artery embolization. Double inferior pulmonary artery are more than double superior pulmonary artery. Pulmonary lobe artery are more than left and right arteries. In shape:center type, totally occluded type is the most, attach wall type has more than irregular type and the saddle type.3.There are closely correlation between the location, type, etc and changes of DECTPA scanning. Lung blood perfusion situation, perfusion image not only in display with mediastinum window on PE pulmonary enhanced image has good experimental data, can also display the lungs blood perfusion situation. Mediastinum window pulmonary enhance image with pulmonary window have poor correlation in diagnosing PE imagz, the lungs perfusion of diagnosis, change different phase in scanning the PE choice have clinical significance.6.There are certain correlations between PE patients CTPA embolism index and arterial blood gas analysis indicators, and right heart function indexes.7.DECTPA group and CTPA group have the same image quality, without increasing the radiation dose.8.When using CARE Dose4D pulmonary scanning method, not only could guarantee the quality of the images,but also could reduce the radiation dose by 50%.