Spiral CT Angiography Research Articles

Clinical value of 256-slice spiral CT and selective coronary angiography for the diagnosis of coronary artery disease

Objective To explore the clinical value of 256-slice CT and coronary angiography in the diagnosis of coronary artery disease.Methods 46 patients with coronary heart disease,who underwent coronary angiography and 256-slice spiral CT were selected.Compare two methods for the detection of coronary artery disease.Results ( 1 ) All 256-slice CT and coronary angiography achieved a satisfactory image,in the diagnosis of coronary artery stenosis and occlusion,the two methods had no statistically significant difference ( P ＞ 0.05 ).(2) according to standard coronary angiography,256-slice spiral CT for the diagnosis of coronary artery stenosis sensitivity was 93.0％ (132/142),specificity was 91.6％ (142/155),positive predictive rate was 91.0％ (132/145),negative predictive rate was 93.4％ (142/152).Conclusion 256-slice spiral CT has a high time resolution,spatial resolution,the display of the coronary artery disease has high sensitivity,specificity,positive predictive value and negative predictive value. Key words: Tomography, Spiral computed; Coronary angiography; Coronary disease; Diagnosis

The clinical application value of multi-slice spiral CT angiography

Objective To explore the clinical application value of multi-slice spiral CT angiography.Methods 28 patients who were suspected cerebrovascular disease were taken cerebrovascular enhanced scan by 16-slice spiral CT,and VR,MIP and MPR post -processing were uset to reconstmct the cerebrovascular image.Results In 28 patients,11 cases were normal,17 cases were abnormal,and among these patients there were 8 cases of abnormal blood vessels,4 cases of aneurysms,1 case of cerebral arteriovenous malformation,4 cases of cerebral artery stenosis.Conclusion The multi-slice CT compared with ordinary spiral CT had the advantage of faster and more secure.It had an important role in guiding the screening and clinical treatment programs in cerebral infarction patients with suspected cerebral artery stenosis.It had a lot of advantages in diagnosis vascular disease and clinical observation after treatment. Key words: Tomography technique,X-ray computed; Cerebral angiography

Assessment of 64-slice spiral computed tomography angiography with image fusion for perigastric arteries anatomy

To evaluate the efficacy and clinical significance of 64-multislice spiral computed tomography angiography(MSCTA) with image fusion for the anatomy of perigastric arteries. A total of 53 patients underwent abdominal 64-MSCTA, among whom 26 patients with gastric cancer underwent gastrectomy. Using volume rendering techniques, computed tomography angiography(CTA) of perigastric arteries and the stomach were reconstructed respectively, and then the images were fused together. The branching pattern of the celiac trunk and the origins and courses along the stomach of the 10 perigastric arteries were assessed. The accuracy, sensitivity, and specificity of 64-MSCTA were determined based on intraoperative findings. CTA clearly showed the celiac trunk. The most common branching pattern of the celiac trunk was Michels type I( in 46 patients(86.8%). The anatomy of perigastric arteries and stomach could be clearly demonstrated from any angle according to image fusion. The left gastric artery and the right gastroepiploic artery were shown in 100%, the left gastroepiploic artery 94.3%(50/53), the right gastric artery 83.0%(44/53), short gastric artery 58.5%(31/53), posterior gastric artery 49.1%(26/53), the replaced left hepatic artery 15.1%(8/53). The accessory left hepatic artery, accessory left gastric artery and replaced right hepatic artery were all identified in 7.5%(4/53) patients. The accuracy of preoperative CTA in term of correctly identifying perigastric arteries ranged from 84.6% to 100%, the sensitivity 82.6% to 100%, and the specificity was 100% for all the perigastric arteries. 64-MSCTA can clearly reveal individual perigastric arteries. The anatomy of the stomach and perigastric arteries can be shown in vivo by fused image, and can provide guidance for gastrectomy.

Bedside noninvasive scoring system in diagnosis of coronary heart disease

Objectives To evaluate the effectiveness of bedside noninvasive scoring system in diagnosis of coronary heart disease (CAD).Methods Six hundred and twelve patients with suspected CAD in our hospital were enrolled (343 males and 269 females) from September 2008 to October 2010,with an average age of 55 ± 7 y.The detailed history was taken; physical examination,resting electrocardiogram,blood biochemistry,treadmill exercise test and/or 12 lead Holter monitoring,64 or 256 rows CT coronary artery imaging and coronary artery angiography were performed in all patients.The risk factors for CAD were screened by multiple questionnaire surveys with Delphi method.The risk factors were stratified according to the results of expert survey: heavy smoking,diabetes mellitus,typical angina,positive treadmill exercise test and positive Holter monitoring electrocardiogram were included in the highest risk factors with an integrated scores of 8 ; dyslipidemia of 3 items,hypertension complicated with left ventricular hypertrophy were high risk factors with an integrated scores of 6; males≥40 y,medium smoking,dyslipidemia of 2 items,pathoglycemia,heavy drinking,positive ECG and post-menopause females were moderate risk factors with integrated scores of 4; Low risk factors contain moderate drinking and dyslipidemia of item,were classified as low risk factors with an integrated scores of 2. The bedside noninvasive scoring system was evaluated in all patients and the results were compared with those from multi-slice spiral CT or coronary angiography.Results When integrated score ≥ 24 was set as the cut-off level for diagnosis of CAD,thesensitivity,specificity,positive predictive value and accuracy were 89.95％,85.63％,94.03％ and 88.73％ respectively.When integrated score≤ 14 was set as the exclusion criteria of CAD,the sensitivity,specificity,positive predictive value and accuracy were of 93.10％,82.86％,98.09％ and 84.80％ respectively.The accuracy was lower than that of multi-slice spiral CT or coronary angiography( P ＜0.05 ).Conclusions The bedside noninvasive scoring system is effective for preliminary diagnose of CAD,but need to be further improved. Key words: Coronary disease; Diagnostic techniques, cardiovascular; Research design

Evaluation of coronary artery in-stent patency using 64-slice computed tomography

Surveillance conventional coronary angiography (CCA) is recommended after stent supported percutaneous coronary intervention due to the unpredictable occurrence of in-stent restenosis (ISR). We explored the ability of 64-slice computed tomography angiography (CTA) to detect ISR after stenting of the coronary artery and analyzed the factors influencing imaging quality. Forty-five consecutive patients (29 stents) were examined by both CCA and 64-slice CTA after percutaneous coronary intervention. We analyzed the correlation between the image quality and heart rate, diameter, position, and stent-strut thickness. Compared with the CCA, the sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CTA for the detection of ISR were calculated. Between the patent group and ISR group, different computed tomography attenuation values of the in-stent lumen and artery 5 mm proximal and distal to the stent were also analyzed. All stents were clearly visualized. With regard to the differences in heart rate, stent position, stent diameter, and stent-strut thickness among the different image quality groups, the P values were 0.47, 0.60, 0.04, and <0.01, respectively. Compared with CCA, the sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CTA were 100, 95.2, 88.9, and 100%, respectively. Between patent and ISR groups, the P values for the differences in CTA attenuation values of the in-stent lumen and artery 5 mm distal to the stent were 0.007 and 0.04, respectively. We found that 64-slice spiral CTA is a reliable noninvasive diagnostic method that can display the stent lumen clearly and is especially helpful for patient follow-up.

Radiation dose considerations by intra-individual Monte Carlo simulations in dual source spiral coronary computed tomography angiography with electrocardiogram-triggered tube current modulation and adaptive pitch

To evaluate radiation dose levels in patients undergoing spiral coronary computed tomography angiography (CTA) on a dual-source system in clinical routine. Coronary CTA was performed for 56 patients with electrocardiogram-triggered tube current modulation (TCM) and heart-rate (HR) dependent pitch adaptation. Individual Monte Carlo (MC) simulations were performed for dose assessment. Retrospective simulations with constant tube current (CTC) served as reference. Lung tissue was segmented and used for organ and effective dose (ED) calculation. Estimates for mean relative ED was 7.1 ± 2.1 mSv/100 mAs for TCM and 12.5 ± 5.3 mSv/100 mAs for CTC (P < 0.001). Relative dose reduction at low HR (≤60 bpm) was highest (49 ± 5%) compared to intermediate (60-70 bpm, 33 ± 12%) and high HR (>70 bpm, 29 ± 12%). However lowest ED is achieved at high HR (5.2 ± 1.5 mSv/100 mAs), compared with intermediate (6.7 ± 1.6 mSv/100 mAs) and low (8.3 ± 2.1 mSv/100 mAs) HR when automated pitch adaptation is applied. Radiation dose savings up to 52% are achievable by TCM at low and regular HR. However lowest ED is attained at high HR by pitch adaptation despite inferior radiation dose reduction by TCM. • Monte Carlo simulations allow for individual radiation dose calculations. • ECG-triggered tube current modulation (TCM) can effectively reduce radiation dose. • Slow and regular heart rates allow for highest dose reductions by TCM. • Adaptive pitch accounts for lowest radiation dose at high heart rates. • Women receive higher effective dose than men undergoing spiral coronary CT-angiography.

The use of 3D computer graphics in the diagnosis and treatment of spinal vascular malformations

Digital subtraction (DS) angiography is the gold standard for diagnosing spinal vascular malformations. Recently, multidetectorrow spiral CT and contrast-enhanced MR angiography have been introduced as screening examinations before DS angiography. These methods, however, do not always determine the accurate location of an arteriovenous shunt because the resulting images lack information about the spinal cord or the dura mater. Between April 2009 and December 2010, 13 patients underwent imaging evaluations for spinal vascular malformations at the authors' university hospital. This group included 8 patients with spinal dural arteriovenous fistulas (AVFs), 3 with perimedullary AVFs, and 2 with intramedullary arteriovenous malformations. Using data from these patients, the authors attempted to develop 3D computer graphics (CG) based upon the fusion of 3D rotational angiography and postmyelographic CT. They subsequently verified the accuracy of this imaging method. Ten of these 13 patients underwent surgical treatment for their lesions (11 AVFs), and for these 11 lesions the authors compared the diagnoses obtained using 3D CG with those obtained using conventional DS angiography. In all 13 cases, 3D CG images of the spinal lesions were successfully developed using the patients' actual data. Four (36%) of 11 AVFs were correctly identified using DS angiography, whereas 10 (91%) were correctly identified using 3D CG. Results from 3D CG of spinal AVFs corresponded well with operative findings, and 3D CG was significantly better than conventional DS angiography at predicting AVF location (p = 0.024, Fisher exact test). To the authors' knowledge, this is the first reported case series in which 3D CG of spinal vascular malformations was used to provide simultaneous, stereoscopic visualization of the spinal vascular system, spinal cord, dura mater, and bone. The 3D CG method provides precise visual images for the diagnosis and treatment of these lesions.

Diagnostic value of 64-slice spiral computed tomographic angiography in vertebral artery stenosis: a meta-analysis

To evaluate the diagnostic value of 64-slice spiral computed tomographic angiography (CTA) in vertebral artery stenosis through a meta-analysis of the relevant data. A database search of Cochrane Library, PubMed, EBSCO, CBM-disc and CNKI was performed to identify the relevant English and Chinese language articles with such keywords as 64-slice computer tomography, angiography and vertebral artery stenosis. Quality evaluation, heterogeneity test and sensitivity and specificity to the qualified original data were conducted. Summary receiver operating characteristic (SROC) curve, the area under curve (AUC) and diagnostic odds ratio (DROC) were also calculated. A total of 4 studies were eligible for meta-analysis. Among them, 1 was graded as A and 3 were graded as B. No heterogeneity was found based upon a fixed effect model. For vertebral artery stenosis > or = 50%, the pooled weighted sensitivity, specificity, DROC and SROC AUC was 0.98 (0.94 -1.00), 0.93 (0.89 -0.96), 526.33 and 0.9899 respectively; while for vertebral artery stenosis > or = 50%, the parameters were 0.98 (0.91 - 1.00), 0.97 (0.94 -0.99), 838.40 and 0.9932 respectively. 64-slice spiral CTA has such a high level of accuracy, sensitivity and specificity in the non-invasive diagnosis of vertebral artery stenosis.

Reproducibility of coronary plaque detection and characterization using low radiation dose coronary computed tomographic angiography in patients with intermediate likelihood of coronary artery disease (ReSCAN study)

The purpose of this study is to evaluate the interscan, interobserver and intraobserver agreement for coronary plaque detection, and characterization using low radiation dose high-pitch spiral acquisition coronary CT angiography (CTA). Two experienced observers independently evaluated coronary CTA datasets from 50 consecutive patients undergoing two 128-slice dual source CT scans within 12 days. Mean (±SD) estimated radiation exposure was 1.5 ± 0.2 mSv per scan. Observers recorded the presence and characterization of coronary plaques as non-calcified or calcified. A "segment involvement score" (SIS) was computed by summing the numbers of segments with any coronary plaque per patient. Reproducibility was assessed using kappa (κ) statistics, paired t test and Bland-Altman analyses. Interscan, interobserver, and intraobserver agreement (κ-values) for detection of any or calcified plaques were 83-94% (κ-values 0.57-0.85), and 67-84% (0.31-0.67) for non-calcified plaques on a patient level. No significant difference was observed in mean interscan or interobserver SIS. Mean (95% CI) intraobserver SIS difference was -0.88 (-1.25; -0.51), P < 0.001, with limits of agreement from -4.7 to 2.9. Low radiation dose high-pitch coronary CTA permits detection of any or calcified plaques with high interscan, interobserver, intraobserver agreement. However, variability for the detection of non-calcified plaque is substantial.

The use of multi-slice spiral CT angiography for hemoptysis

Objective To evaluate the nse of CT angiography in the diagnosis of hemoptysis and guiding the treatment of it with 64-slice spiral CT.Methods Twenty-two patients with repeated and massive hemoptysis underwent chest CT angiography.Results The blood supply of hemoptysis was nonbronchial systemic arteries in 3 patients,single or multiple bronchial arteries in 15 patients,mixed arteries of nonbronchial systemic and bronchial arteries in 3 patients and abnormal systemic arteries in 1 patient.Conclusion With 64-slice spiral CT,CT angiography provided useful information for the treatment of hemoptysis by guiding bronchial arterial embolization. Key words: Hemoptysis; Bronchial axteries; Tomography,X-ray computed; Angiogaphy

Image quality and dose performance of 80 kV low dose scan protocol in high-pitch spiral coronary CT angiography: feasibility study

To investigate the image quality and dose performance of 80kV high-pitch spiral (HPS) coronary CT angiography (CCTA). 106 patients consecutively enrolled into prospectively ECG-triggering HPS CCTA (pitch=3.4) exam using kV/ref. mAs=80/400, 100/370, and 120/370 when patient BMI was ≤22.5 (n=40), between 22.5 and 27.5 (n=53) and >27.5kg/m² (n=13). Image quality was assessed per-segment by two observers independently using a 4-point scale (1-excellent, 4-non-diagnosable). Image noise and signal-to-noise ratio (SNR), contrast-to-noise ratio were measured. Diagnostic image quality was obtained in 503 of 507, 687 of 693, 164 of 167 coronary segments in 80, 100, 120kV groups without significant difference (P=0.482). The proportions of segments with score 1-4 were not significantly different among three kV groups (all P>0.05). Image noise were significantly higher in 80kV group than 100 and 120 groups (P<0.001), while SNR was not (P=0.097). The effective dose of 80kV group (0.36±0.03mSv) was significantly lower than that of 100kV group (0.86±0.08mSv) and 120kV group (1.77±0.18mSv). The mean±SD of HR in all patients was 54.8±5.1bpm. 80kV HPS CCTA is feasible for patient with BMI≤22.5kg/m² which can save 58% dose than 100kV group, while maintain diagnosable image quality.

Computed tomography in the decision for carotid endarterectomy

Computed tomographic angiography (CTA) is being used more frequently in the decision for the carotid endarterectomy. The accuracy of CTA to differentiate between moderate and severe occlusions of the internal carotid artery has been evaluated in this study. After color-flow duplex (CFD) scanning to determine the severity of the stenosis, contrast-enhanced spiral CTA was performed in 60 carotid arteries of 30 patients. 2-D or 3-D time-of-flight MRA techniques and gadolinium enhancement were also used to measure stenosis. Accuracy for moderate, severe and occluded stenoses was calculated. Internal carotid artery stenosis was classified as completely occluded in four, severe in 27, moderate in 25 and mild in four by CFD. There were five total occlusions, and 19 severe, 30 moderate and six mild stenoses by CTA. The overall accuracy of CTA to CFD was 84%, and was 92% and 75% for moderate and severe stenoses, respectively. CTA has identified calcification and ulceration of the plaque. By MRA there were 2 total occlusions, and 33 severe, 19 moderate and six mild stenoses. The overall accuracy of MRA to CFD was 80%, and was 70% and 94% for moderate and severe stenoses, respectively. While MRA is now routinely used to confirm the results of CFD before surgery, the CTA may in time replace the MRA because it better identifies plaque morphology, ulceration and tight stenoses.

Detection of Coronary Artery Stenoses by Low-Dose, Prospectively ECG-Triggered, High-Pitch Spiral Coronary CT Angiography

We sought to evaluate the diagnostic accuracy of a new prospectively electrocardiogram (ECG)-triggered high-pitch scan mode for coronary computed tomography angiography (CTA), which allows an effective dose of less than 1 mSv. Coronary CTA provides increasingly reliable image quality, but the associated radiation exposure can be high. Seventy-five patients with suspected coronary artery disease and in sinus rhythm were screened for participation. After exclusion of 25 patients for body weight >100 kg or failure to lower heart rate to ≤ 60 beats/min, 50 patients were studied by prospectively ECG-triggered high-pitch spiral computed tomography (CT). Coronary CTA was performed using a dual-source CT system with 2 × 128 × 0.6-mm collimation, 0.28-s rotation time, a pitch of 3.4, 100-kVp tube voltage, and current of 320 mA. Data acquisition was prospectively triggered at 60% of the R-R interval and completed within 1 cardiac cycle. Diagnostic accuracy for detection of coronary artery stenoses ≥ 50% diameter stenosis was determined by comparison to invasive coronary angiography. Per-patient diagnostic performance was the primary form of analysis. In all 50 patients (34 males, 59 ± 12 years of age), imaging was successful. For the detection of 16 patients with at least 1 coronary artery stenosis, CT demonstrated a sensitivity of 100% (95% confidence interval [CI]: 79% to 100%) and specificity of 82% (95% CI: 65% to 93%). The positive predictive value was 72% (95% CI: 49% to 89%) and the negative predictive value was 100% (95% CI: 87% to 100%). Sensitivity was 100% (95% CI: 88% to 100%) and specificity was 94% (95% CI: 89% to 97%) on a per-vessel basis. Per-segment sensitivity was 92% (95% CI: 80% to 97%), and specificity was 98% (95% CI: 96% to 98%). Mean dose-length product for coronary CTA was 54 ± 6 mGy · cm, the effective dose was 0.76 ± 0.08 mSv (0.64 to 0.95 mSv). In nonobese patients with a low and stable heart rate, prospectively ECG-triggered high-pitch spiral coronary CTA provides high diagnostic accuracy for the detection of coronary artery stenoses.

Reduction of radiation dose using 80 kV tube voltage: a feasible strategy?

Reduction of radiation dose using 80 kV tube voltage: a feasible strategy?

Value of 64-slice spiral computed tomography angiography in preoperative evaluation of spinal vascular intervention

Objective To investigate the value of 64-slice spiral computed tomography(CT)angiography in preoperative evaluation of spinal vascular intervention.Methods Seventeen patients with segmental injury of the spinal cord underwent the enhanced 64-slice CT scan of the spine.Thin-slice reconstruction was done,with the slice thickness of 0.625 mm and interval of 0.625 mm.The data were transferred to the work station ADW4.2 in DICM format.Image postprocessing technologies such as volume rendering(VR),maximum intensity projection(MIP)and multi-planar reformat(MPR)were used to conduct three-dimensional reconstruction and analyze the anatomical characteristics of radiculomedullary artery.Results Radiculomedullary artery could be found in the thoracolumbar segment of 16 patients(16/17,94%).Among them,one artery(1/17,6%)went into the vertebral canal through the left intervertebral foramen of T4/5,two(2/17,12%)through the left intervertebral foramen of T10/11,one (1/17,6%)through the left intervertebral foramen of T11/12,four(4/17,24%)through the left intervertebral foramen of L1/2,two(2/17,12%)through the left intervertebral foramen of L2/3,two (2/17,12%)through the right intervertebral foramen of T11/12,two(2/17,12%)through the right intervertebral foramen of T12/L1,two(2/17,12%)through the right foramen of L2/3 andl0(10/17,59%)through the left intervertebral foramen.Either CT scan or DSA examination found no radiculomedullary artery in one patient.All the above findings were in accordance with the results of DSA examination.Conclusions Spiral 64-slice CT scan can provide significant preoperative evaluation information for spinal vascular intervention,for it can accurately and visually show the anatomical features of the radiculomedullary artery such as open position,flow tendency,caliber size and spatial relationship with the surrounding vessels. Key words: Tomography,X-ray computed; Radiography interventional,blood vessels; Spinal cord injuries

Sixty-four-slice computed tomography in surgical strategy of portal vein cavernous transformation

To investigate the role of 64-slice computed tomography (CT) in portal vein cavernous transformation to determine surgical strategy. The site of lesions and extent of collateral circulation in 12 pediatric cases of cavernous transformation of the portal vein with surgical treatment were analyzed. Eleven of 12 children had esophageal varices and were treated with lower esophageal and gastric devascularization and splenectomy, and the other case was only treated with splenectomy. There were eight cases with spontaneous spleen/stomach-renal shunt, four with Retzius vein opening, which was reserved during surgery. Three cases of lesions involving the intrahepatic portal vein (PV) were treated with living donor liver transplantation. One patient died from PV thrombosis after liver transplantation, and the rest had no significant complications. The PV, its branches and collateral circulation were clearly seen by 64-slice spiral CT angiography, which helped with preoperative surgical planning.

Clinical significance of multi-slice spiral CT angiography in radical resection of gastric cancer

To explore the clinical significance of preoperative abdominal multi-slice spiral CT angiography (MSCTA) in radical resection of gastric cancer. One hundred and three patients with gastric cancer were divided into two groups according to their desires. Group I( included 57 patients who underwent preoperative MSCTA and group II( included 46 patients who underwent surgery without preoperative MSCTA. All these patients were operated by the same surgical team. Six patients(10.5%) with abnormal gastric artery in group I( were discovered. The diagnostic concordance rate between MSCTA and intraoperative findings was 100% in group I( in the locations and alignments of main perigastric vessels and their relationship with cancer lesions. Operative time in group I( was shorter than that in group II( [(206 ± 23) min vs. (257 ± 32) min, P=0.044]. Operative time [(190 ± 50) min] of patients with abnormal gastric artery of group I( was shorter than that [(255 ± 62) min] of patients with abnormal gastric artery discovered during operation of group II( (P=0.048). However there were no differences in blood loss, extent of lymph node dissection, complication rate, length of hospital stay, and hospitalization cost between the two groups(P>0.05). Preoperative MSCTA is beneficial to the evaluation of vascular structure of the cancer and the adjacent tissues, which may reduce postoperative complications.

Dual-energy computed tomographic angiography of head and neck with dual-source computed tomography: image quality and radiation dose

To investigate the image quality and radiation dose of dual-energy (DE) computed tomographic angiography (CTA) of head and neck. We retrospectively analyzed two groups of patients (both n=30) undergoing 64-slice spiral CTA of cervical and cranial regions with different scan protocols. The DE group was obtained with 140/80 kVp, 64/272 mAs, 0.6 pitch, 80 ml of contrast medium, and caudal-cranial scan orientation. The single-energy (SE) group was obtained with 120 kVp, 220 mAs, 1.2 pitch, 60 ml of contrast medium and cranial-caudal scan orientation. The image quality and radiation dose were compared. The attenuation values and noises were measured on transverse images at 4 different vessels (the distal part of common carotid artery and adjacent vein in same axial image; the M1 segment of middle cerebral artery and sigmoid sinus or confluence of sinus in same image) and two muscles: erector spinae presenting average soft tissue enhancement and supraspinatus muscle presenting regions of great artifact. In cranial region the arterial enhancement and venous contamination were similar (P=0.1427,P=0.1116) . In cervical region the arterial enhancement was similar (P=0.9414) . DE group had significantly greater venous contamination (P<0.0001) , while the mean attenuation value of common carotid artery was still 127 Hu higher than that of jugular vein. No matter artifact of soft tissue was obvious or not, the noise of DE group was significantly less than that of SE group (both P<0.0001) , and the soft tissue enhancement was similar (P=0.0760,P=0.0793) . The radiation dose required for bone-subtraction angiography was significantly less in DE group than in SE group (P<0.0001) . DE group has comparable image quality to SE group and less scan dose for bone-subtraction. DE-CTA has great potential in clinical application. "

Analysis of clinical application of coronary artery imaging with 64-slice spiral CT

Objective To explore clinical application of coronary artery imaging with 64-slice spiral CT.Methods 46 patients with coronary heart disease were undergone both coronary artery imaging with 64-slice spiral CT and coronary angiography,and the effects on coronary display respectively were compared Results Coronary display in coronary artery imaging with 64-slice spiral CT was better than that of the coronary angiography, which was a inspection pattern of noninvasive coronary display. Conclusion Coronary artery imaging with 64-slice spiral CT can accurately evaluate coronary artery stenosis, which was worth to application. Key words: Coronary disease; Imaging,three-dimensional

Theory and Practice of Pulmonary Embolism Diagnosis at a Large Urban Medical Center

PURPOSE: The incidence of pulmonary embolism (PE) is estimated to be approximately one in one thousand patients with an annual mortality of 300,000. Many clinical prediction scoring systems have been developed that aid the clinician in determining the pretest probability for the diagnosis of PE. One of the best known prediction systems is the Well's criteria. Our study's purpose was to determine whether practitioners at an urban academic medical center consider established risk factors to assess pretest probability prior to ordering a spiral CTA (Computed Tomography Angiography).