To accelerate the scan speed and improve the image quality, a new type of CT configuration, "double-source double-multislice spiral CT" (DSDMS-CT), which is based on two sets of single-source multislice spir...To accelerate the scan speed and improve the image quality, a new type of CT configuration, "double-source double-multislice spiral CT" (DSDMS-CT), which is based on two sets of single-source multislice spiral CT was proposed with a special reconstruction algorithm. Simulation results using the fan-beam filtered backprojection algorithm with a special interpolation method were presented for both single-source multislice spiral CT and DSDMS-CT. The results of new CT model show that it scans faster than the traditional spiral CT and has a better slice sensitivity profile (SSP) with larger pitch value.展开更多
AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgerie...AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer,and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients.Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection,the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.展开更多
Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislic...Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a potentially effective alternative to invasive coronary angiography in patients with suspected coronary artery disease. High diagnostic value has been achieved with multislice CT angiography with use of 64- and more slice CT scanners. In addition, multislice CT angiography shows accurate detection and analysis of coronary calcium, characterization of coronary plaques, as well as prediction of the disease progression and major cardiac events. Thus, patients can benefit from multislice CT angiography that provides a rapid and accurate diagnosis while avoiding unnecessary invasive coronary angiography procedures. The aim of this article is present an overview of the clinical applications of multislice CT angiography in coronary artery disease with a focus on the diagnostic accuracy of coronary artery disease; prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques. Limitations of multislice CT angiography in coronary artery disease are also briefly discussed, and future directions are highlighted.展开更多
Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Me...Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Methods Seventy patients with clinical or pathological diagnosis of functioning pancreatic islet cell tumor between October 2003 and February 2007 were included in this retrospective study. Seventy-four enhanced MSCT scans in these patients were identified. All MSCT scans were interpreted by two experienced radiologists by consensus interpretation. Surgery and pathology reports were used to confirm the diagnosis, localization, and size of tumors. Results Totally, 73 functioning islet cell tumors including 65 benign insulinomas, 2 benign glucagonomas, 3 malignant insulinomas, and 3 malignant glucagonomas were pathologically diagnosed. Tumors in only two cases were not found by MSCT. In 67 benign lesions, 32 showed typical enhancement style, 21 showed prolonged enhancement in portal venous phase, 4 showed delayed enhancement, 4 had iso-dense enhancement with normal pancreatic parenchyma, 2 had no enhancement at all in arterial phase and portal venous phase, and 4 had inhomogeneous enhancement with necrosis or cyst-formation. Patchy or spotty calcifications were found in 3 of the 67 tumors. In 6 malignant islet cell tumors, vessel invasion （2/6） and bowel invasion （1/6） were seen. Different enhancement patterns were shown. All hepatic metastases showed hyper-enhancement during their arterial phase. Conelttsions Pancreatic islet cell tumor may display a wide spectrum of presentations in MSCT. Tumors with unusual appearances often present as diagnostic challenges. Non-contrast and post-contrast multiphase scans are recommended for the localization of functioning islet cell tumors.展开更多
BACKGROUND: Orthotopic liver transplantation has be- come the treatment of choice for patients with end-stage liver disease. This study was designed to study whether multislice spiral CT angiography (MSCTA) could be u...BACKGROUND: Orthotopic liver transplantation has be- come the treatment of choice for patients with end-stage liver disease. This study was designed to study whether multislice spiral CT angiography (MSCTA) could be used for preoperative evaluation for orthotopic liver transplanta- tion candidates. METHODS: Eighty consecutive potential candidates for liver transplantation were evaluated with dual-phase three-di- mensional CT angiography (3DCTA). The arterial-phase was used to create vascular maps of the celiac axis (inclu- ding the origin of the hepatic common artery, left gastric artery and splenic artery) and origin of the superior mesen- teric artery. The portal venous-phase was used to analyze portal vein thrombosis and collateral vascularization of the portal vein. Statistical analyses were made using the chi- square test for differences between hepatic arterial anatomy of 80 patients and Michel's anatomy of 200 patients. Appearance of MSCTA and operative results of 16 patients were analyzed. RESULTS; Sixty-two patients (77.5%) showed conven- tional and 18 (22.5%) nonconventional hepatic arterial anatomy. A significant difference was found between the two groups in anatomy of the hepatic artery (P <0.05). Celiac axis stenosis was observed in 6 patients, SA aneu- rysm in 2, small-caliber hepatic arterial vessels in 2, and portal vein thrombosis in 15. Vascular structures of 16 ope- rative patients were well defined. CONCLUSION: As a noninvasive examination, MSCTA can provide a comprehensive preoperative vascular evalua- tion for liver transplantation candidates.展开更多
Controlled aliasing in parallel imaging results in higher acceleration （CAIPIRINHA） for simultaneous multislice imaging has been proposed recently, which combines multiband excitation and phase cycling techniques to...Controlled aliasing in parallel imaging results in higher acceleration （CAIPIRINHA） for simultaneous multislice imaging has been proposed recently, which combines multiband excitation and phase cycling techniques to reduce scan time and improve subsequent imaging reconstruction. In this work, the total variation （TV） regularization method is used to further improve CAIPIRINHA. The TV regularization uses an edge-preserving prior, which establishes a relationship between neighboring pixels for image reconstruction. It reduces artifacts and suppresses noise amplification simultaneously. The results are presented with a standard eight-channel head coil with an acceleration factor of 4, where the TV-regularized CAIPIRINHA generates an improved reconstruction as compared with a typical nonregularized CAIPIRINHA.展开更多
The purpose of this study was to compare and analyze the diagnostic applications of multisliecs spiral computed tomography(MSCT)and diffusively-weighted magnetic resonance imaging(MRI)in soft tissue tumors of extremit...The purpose of this study was to compare and analyze the diagnostic applications of multisliecs spiral computed tomography(MSCT)and diffusively-weighted magnetic resonance imaging(MRI)in soft tissue tumors of extremities.A total of 104 patients with primary soft tissue tumors of limbs were selected for MSCT and MRI examination.MSCT values of various tumor types were compared during CT examination.In MRI detection,the diffusion sensitivity factor(b)of diffuse-weighted MRI was 0.500 s/mm2 to avoid as much as possible the bleeding,necrosis,scar and calcification heterogeneity components during operation.The maximum interest point was selected to observe the apparent diffusion coefficient(ADC)between benign and malignant tumors and muscle tissue.Results showed that among 104 patients,36 of patients were malignant and 68 of patients were benign.MSCT examination was consistent with pathology in 45 cases and MRI in 87 cases.In addition,the 59 of patients in MSCT examination and the 17 of patients in MRI were qualitative error and uncertainty.Soft tissue tumors on MSCT showed a low-density mass,and lipoma and cyst were specific.In MRI examination,T1WI and T2WI were significantly different in different types of tumors,while ADC values of malignant tumors were significantly lower than those of benign tumors and muscle tissues(P<0.01).However,there was no significant difference in ADC between benign tumor and muscle tissue(P>0.05).Therefore,MSCT can clearly show the soft tissue tumor lesions of the limbs and identify the relationship between them and the surrounding tissues.However,MSCT cannot make accurate characterization.MRI diffusivity weighted imaging can better differentiate benign from malignant and infer the histological origin of lesions.The detection level of MRI was significantly higher than that of CT,which was more consistent with pathology.Therefore,in the preoperative diagnosis of soft tissue tumors in limbs,MRI diffused-weighted imaging should be the first choice.展开更多
Objective: to analyze the characteristics of low-dose multi-slice spiral CT (MSCT) in neonates with pulmonary diseases, and to compare its manifestations with X-ray, and to explore the application value of low-dose MS...Objective: to analyze the characteristics of low-dose multi-slice spiral CT (MSCT) in neonates with pulmonary diseases, and to compare its manifestations with X-ray, and to explore the application value of low-dose MSCT in diagnosis. Methods A total of 76 neonates with pulmonary diseases in our hospital were selected as subjects from August 2020 to August 2021. At the same time, it is necessary to let patients and their families know the content and purpose of this study to protect their right to know and lay a foundation for subsequent studies. Results In 76 neonatal patients, clinical diagnosis can be found: Pneumonia, 61, 13 meconium inhalation disease performance, wet lung symptoms in 1 case, pulmonary hemosiderosis of cases for 1 case, through the low doses of multislice CT screening examination, found that more than four children each is 58 cases of the disease, 10, 1, 1 case, then the compared with the clinical diagnosis, conformity degree is 92.11%;Through X-ray screening, the number of children with the above four diseases was found to be 50, 4, 1 and 1 respectively, so the coincidence was 73.68% compared with the clinical diagnosis. From this point of view, the coincidence rate of screening results is much higher than that of X-ray after selecting low-dose multi-slice spiral CT for diagnosis compared with clinical diagnosis results. Conclusion For clinical diagnosis of neonatal lung diseases, low-dose MSCT can accurately detect some relatively hidden or obscure lesions, and has a prominent advantage compared with X-ray, so it has a certain practical value in clinical diagnosis and application. As medical staff, in the future clinical application, patients should be recommended to use multi-slice spiral CT technology for examination as far as possible to ensure the accuracy of the examination effect.展开更多
Congenital aorta-right atrial tunnel(ARAT)is a rare congenital cardiovascular malformation characterized by an abnormal tunnel-like connection between the aorta and the right atrium.Patients with ARAT frequently have ...Congenital aorta-right atrial tunnel(ARAT)is a rare congenital cardiovascular malformation characterized by an abnormal tunnel-like connection between the aorta and the right atrium.Patients with ARAT frequently have other congenital heart malformations and require diagnosis through a variety of imaging examinations.We report a 1-month-old female infant with multiple congenital cardiac malformations who was diagnosed with ARAT using low-dose multislice spiral computed to-mography because echocardiography was unclear.展开更多
Background Invasive intravascular ultrasound （IVUS） is current diagnostic standard for myocardial bridging （MB）. Non-invasive multislice computerized tomography coronary angiography （MSCT） technique has provided...Background Invasive intravascular ultrasound （IVUS） is current diagnostic standard for myocardial bridging （MB）. Non-invasive multislice computerized tomography coronary angiography （MSCT） technique has provided a good anatomical view of the tunnel artery now. Methods A total of 51 consecutive patients with atypical or typical angina scheduled for IVUS were enrolled in this study and MSCT was performed 7 days before IVUS. Coronary imaging was quantified using IVUS and MSCT. Four main vessels （left main artery （LMA）, left anterior descending （LAD）, left circumflex （LCX）, right coronary artery （RCA）） were examined. Results Forty-one out of 51 （80%） patients received metaprolol （25 mg） before the MSCT scan and 25 of them were current beta-blocker users. The mean heart rate was （64_＋3） beats per minute. A total of 51 patients underwent IVUS examination （30 with MB and 21 without MB） were chosen for this study. Twenty-eight out of 30 MB cases were correctly diagnosed by MSCT and 2 patients with MB were not detected. Comparison with IVUS, the sensitivity of detection by MSCT was 93%, specificity was 100%. The lumen diameter of the tunnel artery derived from MSCT and IVUS significantly decreased from （2.9±0.3） mm to （2.4±0.4） mm （P〈0.001） and from （3.3±0.3） mm to （2.6±0.5） mm （P〈0.001）, respectively. Minimal and maximal diameters of MB derived from MSCT were significantly smaller than those from IVUS （（2.4±0.4） mm vs （2.6±0.5） mm, P〈0.05 and （2.9±0.3） mm vs （3.3±0.3） mm, P〈0.05）, respectively. Conclusions MSCT offers a reliable non-invasive method for MB in LAD and atherosclerosis diagnosis with diagnostic accuracy comparable with invasive IVUS.展开更多
Background There are few reports of quantitative and qualitative measuring of left main coronary artery （LMCA） plaques by multislice computed tomography coronary angiography （MSCTA）, especially when compared with ...Background There are few reports of quantitative and qualitative measuring of left main coronary artery （LMCA） plaques by multislice computed tomography coronary angiography （MSCTA）, especially when compared with intravascular ultrasound （IVUS） as reference standard. The aim of this study was to evaluate the use of 64-MSCTA in the diagnosis of LMCA disease, and the accuracy of MSCTA in the quantitative and qualitative assessment of the LMCA lesion as compared with IVUS.Methods A total of 91 patients （53 men, 38 women, mean age （64.78±9.19） years） were examined by 64-MSCTA and IVUS. Compared with the IVUS, the sensitivity, specificity, positive and negative predictive values （PPV and NPV） of the MSCTA on the diagnosis of LMCA diseases were calculated. Also, kappa index （K） for the agreement between MSCTA and IVUS was calculated. Minimal lumen area （MLA）, external elastic membrane cross-sectional area （EEM-CSA） and plaque burden were measured by two blinded and independent operators on MSCTA cross-sectional reconstruction and compared with the parameters measured from IVUS by manually tracing. The CT value of soft, fibrous and calcific plaques was measured using IVUS classification of the plaques.Results The sensitivity, specificity, PPV and NPV of MSCTA for detecting LMCA plaques were 93.1%, 84.2%, 95.7%, 76.2%, respectively. Kappa index （K=0.744, P〈0.001） indicated excellent agreement between MSCTA and IVUS. The Pearson index between MLA on IVUS and MLA on MSCTA was 0.815 （P 〈0.01）. The Pearson index of plaque burden and EEM-CSA between IVUS and MSCTA was 0.736 and 0.740 respectively （both P 〈0.01）. The CT value of soft plaque, fibrous plaque and calcific plaque compared with IVUS were （52.52±15.71） HU, （108.32±43.44） HU and （604.16±377.67） HU （P〈0.001）. Receiver operating characteristic curve analysis of CT value of non-calcific plaques for predicting soft plaques showed the cutpoint was 54.35 HU, with a sensitivity of 83.3% and specificity of 94.4%. Conclusions Sixty-four section MSCTA is an effective diagnostic tool for the detection of LMCA plaques with higher sensitivity and specificity. The correlation of quantitative and qualitative analysis between MSCTA and IVUS was excellent. The CT value of plaques can help the diagnosis of plaque composition.展开更多
Conventional ultrasound （US） is the most widely used imaging modality in routine clinical practice worldwide. The limitations of conventional ultrasound in the detection of aortic lesions versus multi-slice compute...Conventional ultrasound （US） is the most widely used imaging modality in routine clinical practice worldwide. The limitations of conventional ultrasound in the detection of aortic lesions versus multi-slice computed tomography angiography （MS-CTA） are well known.展开更多
Background Multislice helical computed tomography (MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy...Background Multislice helical computed tomography (MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy of ventricular volume as measured by MSCT.Methods Fourteen human left ventricular (LV) and 15 right ventricular (RV) casts were scanned by MSCT. A series of LV and RV short-axis images were reconstructed later with slice thickness of 2.0 mm, 3.5 mm, 5.0 mm, 7.0 mm, and 10.0 mm. Ventricular volume was calculated by the multislice tomographic Simpson’s method. True LV and RV cast volumes were determined by water displacement. Results Both calculated LV and RV volumes correlated highly with the corresponding true volumes (all r>0.95, P<0.01). But with slice thickness from 2.0 mm to 10.0 mm, MSCT scanning overestimated the corresponding true volume by (3.21±5.95) ml to (12.58±8.56) ml for LV and (10.22±8.45) ml to (23.91±12.24) ml for RV (all P<0.01). There was a very high correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements (r=0.998 and 0.996, P<0.01, respectively). However, when slice thickness was reduced to 5.0 mm, the overestimation for both LV and RV volume measurements became nonsignificant for slice thickness from 2.0 mm to 5.0 mm. Conclusions Both LV and RV volumes can be accurately estimated by MSCT. Thinner slice has more accurate calculated volume. However, 5.0 mm slice thickness is thin enough for an accurate measurement of LV or RV volume.展开更多
Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compare...Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compared to invasive coronary angiography.Diagnostic performance of coronary CT angiography has been significantly improved with the technological developments in multislice CT scanners from the early generation of 4-slice CT to the latest 320-slice CT scanners.Despite the promising diagnostic value,coronary CT angiography is still limited in some areas,such as inferior temporal resolution,motion-related artifacts and high false positive results due to severe calcification.The aim of this review is to present an overview of the technical developments of multislice CT and diagnostic value of coronary CT angiography in coronary artery disease based on different generations of multislice CT scanners.Prognostic value of coronary CT angiography in coronary artery disease is also discussed,while limitations and challenges of coronary CT angiography are highlighted.展开更多
AIM: To investigate the research directions of coronary computed tomography (CT) angiography in the diagnosis of coronary artery disease (CAD) based on a systematic review of the literature.METHODS: A search of articl...AIM: To investigate the research directions of coronary computed tomography (CT) angiography in the diagnosis of coronary artery disease (CAD) based on a systematic review of the literature.METHODS: A search of articles on coronary CT angiography in the diagnosis of CAD was performed during a 6-year-period between 2005 and 2010 from f ive main radiology journals namely, Radiology, American Journal of Roentgenology, European Radiology, European Journal of Radiology and British Journal of Radiology. Analysis of the references was focused on the research directions of coronary CT angiography with regard to the type of studies in terms of diagnostic value, application of dose-reduction strategies and resultant effective radiation doses with use of these techniques.RESULTS: One hundred and forty two studies were identified which met the selection criteria and were included in the analysis. 64-slice CT (single source anddual-source CT) dominated 78% of the coronary CT angiography studies. Prior to 2007, research was focused on the diagnostic value of coronary CT angiography, but since 2008 more attention has been paid to radiation dose reduction. Radiation dose was reported in 64 studies, representing 45% of total studies published in the f ive radiology journals. Various dose-saving strategies have been implemented and prospective electrocardiography-triggering and high pitch techniques were found to be the most effective approaches for radiation dose reduction, with the corresponding mean effective dose being 3.5 ± 1.9 mSv and 1.7 ± 0.6 mSv, respectively.CONCLUSION: This review shows that the current research in coronary CT angiography has shifted from the previous focus on diagnostic accuracy in CAD to more emphasis on radiation dose reduction.展开更多
Atrial fibrillation is the most common arrhythmia and in symptomatic patients with a drug-refractory form,catheter ablation aimed at electrically disconnecting the pulmonary veins(PVs) has proved more effective than u...Atrial fibrillation is the most common arrhythmia and in symptomatic patients with a drug-refractory form,catheter ablation aimed at electrically disconnecting the pulmonary veins(PVs) has proved more effective than use of antiarrhythmic drugs in maintaining sinus rhythm during follow-up.On the other hand,this ablation procedure is complex,requires specific training and adequate clinical experience.A main challenge is represented by the need for accurate sequential positioning of the ablation catheter around each veno-atrial junction to deliver point-by-point radiofrequency energy applications in order to achieve complete and persistent electrical disconnection of the PVs.Imaging integration is a new technology that enables guidance during this procedure by showing a three-dimensional,pre-acquired computed tomography or magnetic resonance image and the relative real-time position of the ablation catheter on the screen of the electroanatomic system.Reports in the literature suggest that imaging integration provides accurate visual information with improvement in the procedure parameters and/or clinical outcomes of the procedure.展开更多
Thin cap fibroatheromas(TCFAs) are thought to be the most common underlying substrate in patients suffering acute coronary thrombotic events.Recently,an interesting association between TCFAs and a particular depot of ...Thin cap fibroatheromas(TCFAs) are thought to be the most common underlying substrate in patients suffering acute coronary thrombotic events.Recently,an interesting association between TCFAs and a particular depot of visceral fat called epicardial adipose tissue(EAT) has been suggested.In this article,we discuss some basic and clinical aspects of this association and then briefly review some of the pathophysiological characteristics attributed to EAT that explain why this particular depot of fat has been attracting the attention of the cardiological scientific community in recent years.Finally we discuss the value of optical coherence tomography in the diagnosis of TCFAs and the role of multislice computed tomography to assess EAT.展开更多
Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compare...Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compared to invasive coronary angiography.Diagnostic performance of coronary CT angiography has been significantly improved with the technological developments in multislice CT scanners from the early generation of 4-slice CT to the latest 320-slice CT scanners.Despite the promising diagnostic value,coronary CT angiography is still limited in some areas,such as inferior temporal resolution,motion-related artifacts and high false positive results due to severe calcification.The aim of this review is to present an overview of the technical developments of multislice CT and diagnostic value of coronary CT angiography in coronary artery disease based on different generations of multislice CT scanners.Prognostic value of coronary CT angiography in coronary artery disease is also discussed,while limitations and challenges of coronary CT angiography are highlighted.展开更多
With the introduction of 64- and post-64 slice computed tomography(CT)technology,coronary CT angiography has been increasingly used as a less invasive modality for the diagnosis of coronary artery disease.Despite its ...With the introduction of 64- and post-64 slice computed tomography(CT)technology,coronary CT angiography has been increasingly used as a less invasive modality for the diagnosis of coronary artery disease.Despite its high diagnostic value and promising results compared to invasive coronary angiography,coronary CT angiography is associated with high radiation dose,leading to potential risk of radiation-induced cancer.A variety of dose-reduction strategies have been reported recently to reduce radiation dose with effective outcomes having been achieved.This article presents an overview of the various methods currently used for radiation dose reduction.展开更多
Background:Although computed tomography coronary angiography (CTCA) can identify coronary stenosis,little data exists on the ability of multislice computed tomography (MSCT) to detect myocardial perfusion defects at r...Background:Although computed tomography coronary angiography (CTCA) can identify coronary stenosis,little data exists on the ability of multislice computed tomography (MSCT) to detect myocardial perfusion defects at rest.Methods:In 33 patients with diagnosed or suspected coronary artery disease (CAD),CTCA using retrospective electrocardiography (ECG) gating at rest and invasive coronary angiography (ICA) was performed.The 2D myocardial images were reconstructed in diastolic and systolic phases using the same raw data for CTCA.CT values of the myocardium were used as an estimate of myocardial enhancement,which were shown by color mapping.Myocardial ischemia was defined as a pattern of transient endocardial hypo-enhancement at systole and normal enhancement at diastole.The results of ICA were taken as the reference standard.Results:When a diameter reduction of more than 50% in ICA was used as diagnostic criteria of CAD,the sensitivity,specificity,positive predictive value (PPV),and negative predictive value (NPV) of CT first-pass myocardial perfusion imaging (MPI) at rest were 0.85,0.67,0.92,and 0.50 per patient,respectively,and 0.58,0.93,0.85,and 0.76 per vessel,respectively.Conclusions:CT first-pass MPI at rest could detect CAD patients,which could become a practical and convenient way to detect ischemia,consequently offering the ability for MSCT to act as a "one stop shop" for the diagnosis of CAD.展开更多
基金The National Natural Science Foundation ofChina (No30570511)
文摘To accelerate the scan speed and improve the image quality, a new type of CT configuration, "double-source double-multislice spiral CT" (DSDMS-CT), which is based on two sets of single-source multislice spiral CT was proposed with a special reconstruction algorithm. Simulation results using the fan-beam filtered backprojection algorithm with a special interpolation method were presented for both single-source multislice spiral CT and DSDMS-CT. The results of new CT model show that it scans faster than the traditional spiral CT and has a better slice sensitivity profile (SSP) with larger pitch value.
文摘AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer,and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients.Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection,the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.
文摘Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a potentially effective alternative to invasive coronary angiography in patients with suspected coronary artery disease. High diagnostic value has been achieved with multislice CT angiography with use of 64- and more slice CT scanners. In addition, multislice CT angiography shows accurate detection and analysis of coronary calcium, characterization of coronary plaques, as well as prediction of the disease progression and major cardiac events. Thus, patients can benefit from multislice CT angiography that provides a rapid and accurate diagnosis while avoiding unnecessary invasive coronary angiography procedures. The aim of this article is present an overview of the clinical applications of multislice CT angiography in coronary artery disease with a focus on the diagnostic accuracy of coronary artery disease; prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques. Limitations of multislice CT angiography in coronary artery disease are also briefly discussed, and future directions are highlighted.
文摘Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography （MSCT） and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Methods Seventy patients with clinical or pathological diagnosis of functioning pancreatic islet cell tumor between October 2003 and February 2007 were included in this retrospective study. Seventy-four enhanced MSCT scans in these patients were identified. All MSCT scans were interpreted by two experienced radiologists by consensus interpretation. Surgery and pathology reports were used to confirm the diagnosis, localization, and size of tumors. Results Totally, 73 functioning islet cell tumors including 65 benign insulinomas, 2 benign glucagonomas, 3 malignant insulinomas, and 3 malignant glucagonomas were pathologically diagnosed. Tumors in only two cases were not found by MSCT. In 67 benign lesions, 32 showed typical enhancement style, 21 showed prolonged enhancement in portal venous phase, 4 showed delayed enhancement, 4 had iso-dense enhancement with normal pancreatic parenchyma, 2 had no enhancement at all in arterial phase and portal venous phase, and 4 had inhomogeneous enhancement with necrosis or cyst-formation. Patchy or spotty calcifications were found in 3 of the 67 tumors. In 6 malignant islet cell tumors, vessel invasion （2/6） and bowel invasion （1/6） were seen. Different enhancement patterns were shown. All hepatic metastases showed hyper-enhancement during their arterial phase. Conelttsions Pancreatic islet cell tumor may display a wide spectrum of presentations in MSCT. Tumors with unusual appearances often present as diagnostic challenges. Non-contrast and post-contrast multiphase scans are recommended for the localization of functioning islet cell tumors.
文摘BACKGROUND: Orthotopic liver transplantation has be- come the treatment of choice for patients with end-stage liver disease. This study was designed to study whether multislice spiral CT angiography (MSCTA) could be used for preoperative evaluation for orthotopic liver transplanta- tion candidates. METHODS: Eighty consecutive potential candidates for liver transplantation were evaluated with dual-phase three-di- mensional CT angiography (3DCTA). The arterial-phase was used to create vascular maps of the celiac axis (inclu- ding the origin of the hepatic common artery, left gastric artery and splenic artery) and origin of the superior mesen- teric artery. The portal venous-phase was used to analyze portal vein thrombosis and collateral vascularization of the portal vein. Statistical analyses were made using the chi- square test for differences between hepatic arterial anatomy of 80 patients and Michel's anatomy of 200 patients. Appearance of MSCTA and operative results of 16 patients were analyzed. RESULTS; Sixty-two patients (77.5%) showed conven- tional and 18 (22.5%) nonconventional hepatic arterial anatomy. A significant difference was found between the two groups in anatomy of the hepatic artery (P <0.05). Celiac axis stenosis was observed in 6 patients, SA aneu- rysm in 2, small-caliber hepatic arterial vessels in 2, and portal vein thrombosis in 15. Vascular structures of 16 ope- rative patients were well defined. CONCLUSION: As a noninvasive examination, MSCTA can provide a comprehensive preoperative vascular evalua- tion for liver transplantation candidates.
基金Project supported by the National Natural Science Foundation of China(Grant No.61671026)the Natural Science Foundation of Beijing,China(Grant No.7162112)
文摘Controlled aliasing in parallel imaging results in higher acceleration （CAIPIRINHA） for simultaneous multislice imaging has been proposed recently, which combines multiband excitation and phase cycling techniques to reduce scan time and improve subsequent imaging reconstruction. In this work, the total variation （TV） regularization method is used to further improve CAIPIRINHA. The TV regularization uses an edge-preserving prior, which establishes a relationship between neighboring pixels for image reconstruction. It reduces artifacts and suppresses noise amplification simultaneously. The results are presented with a standard eight-channel head coil with an acceleration factor of 4, where the TV-regularized CAIPIRINHA generates an improved reconstruction as compared with a typical nonregularized CAIPIRINHA.
文摘The purpose of this study was to compare and analyze the diagnostic applications of multisliecs spiral computed tomography(MSCT)and diffusively-weighted magnetic resonance imaging(MRI)in soft tissue tumors of extremities.A total of 104 patients with primary soft tissue tumors of limbs were selected for MSCT and MRI examination.MSCT values of various tumor types were compared during CT examination.In MRI detection,the diffusion sensitivity factor(b)of diffuse-weighted MRI was 0.500 s/mm2 to avoid as much as possible the bleeding,necrosis,scar and calcification heterogeneity components during operation.The maximum interest point was selected to observe the apparent diffusion coefficient(ADC)between benign and malignant tumors and muscle tissue.Results showed that among 104 patients,36 of patients were malignant and 68 of patients were benign.MSCT examination was consistent with pathology in 45 cases and MRI in 87 cases.In addition,the 59 of patients in MSCT examination and the 17 of patients in MRI were qualitative error and uncertainty.Soft tissue tumors on MSCT showed a low-density mass,and lipoma and cyst were specific.In MRI examination,T1WI and T2WI were significantly different in different types of tumors,while ADC values of malignant tumors were significantly lower than those of benign tumors and muscle tissues(P<0.01).However,there was no significant difference in ADC between benign tumor and muscle tissue(P>0.05).Therefore,MSCT can clearly show the soft tissue tumor lesions of the limbs and identify the relationship between them and the surrounding tissues.However,MSCT cannot make accurate characterization.MRI diffusivity weighted imaging can better differentiate benign from malignant and infer the histological origin of lesions.The detection level of MRI was significantly higher than that of CT,which was more consistent with pathology.Therefore,in the preoperative diagnosis of soft tissue tumors in limbs,MRI diffused-weighted imaging should be the first choice.
文摘Objective: to analyze the characteristics of low-dose multi-slice spiral CT (MSCT) in neonates with pulmonary diseases, and to compare its manifestations with X-ray, and to explore the application value of low-dose MSCT in diagnosis. Methods A total of 76 neonates with pulmonary diseases in our hospital were selected as subjects from August 2020 to August 2021. At the same time, it is necessary to let patients and their families know the content and purpose of this study to protect their right to know and lay a foundation for subsequent studies. Results In 76 neonatal patients, clinical diagnosis can be found: Pneumonia, 61, 13 meconium inhalation disease performance, wet lung symptoms in 1 case, pulmonary hemosiderosis of cases for 1 case, through the low doses of multislice CT screening examination, found that more than four children each is 58 cases of the disease, 10, 1, 1 case, then the compared with the clinical diagnosis, conformity degree is 92.11%;Through X-ray screening, the number of children with the above four diseases was found to be 50, 4, 1 and 1 respectively, so the coincidence was 73.68% compared with the clinical diagnosis. From this point of view, the coincidence rate of screening results is much higher than that of X-ray after selecting low-dose multi-slice spiral CT for diagnosis compared with clinical diagnosis results. Conclusion For clinical diagnosis of neonatal lung diseases, low-dose MSCT can accurately detect some relatively hidden or obscure lesions, and has a prominent advantage compared with X-ray, so it has a certain practical value in clinical diagnosis and application. As medical staff, in the future clinical application, patients should be recommended to use multi-slice spiral CT technology for examination as far as possible to ensure the accuracy of the examination effect.
文摘Congenital aorta-right atrial tunnel(ARAT)is a rare congenital cardiovascular malformation characterized by an abnormal tunnel-like connection between the aorta and the right atrium.Patients with ARAT frequently have other congenital heart malformations and require diagnosis through a variety of imaging examinations.We report a 1-month-old female infant with multiple congenital cardiac malformations who was diagnosed with ARAT using low-dose multislice spiral computed to-mography because echocardiography was unclear.
文摘Background Invasive intravascular ultrasound （IVUS） is current diagnostic standard for myocardial bridging （MB）. Non-invasive multislice computerized tomography coronary angiography （MSCT） technique has provided a good anatomical view of the tunnel artery now. Methods A total of 51 consecutive patients with atypical or typical angina scheduled for IVUS were enrolled in this study and MSCT was performed 7 days before IVUS. Coronary imaging was quantified using IVUS and MSCT. Four main vessels （left main artery （LMA）, left anterior descending （LAD）, left circumflex （LCX）, right coronary artery （RCA）） were examined. Results Forty-one out of 51 （80%） patients received metaprolol （25 mg） before the MSCT scan and 25 of them were current beta-blocker users. The mean heart rate was （64_＋3） beats per minute. A total of 51 patients underwent IVUS examination （30 with MB and 21 without MB） were chosen for this study. Twenty-eight out of 30 MB cases were correctly diagnosed by MSCT and 2 patients with MB were not detected. Comparison with IVUS, the sensitivity of detection by MSCT was 93%, specificity was 100%. The lumen diameter of the tunnel artery derived from MSCT and IVUS significantly decreased from （2.9±0.3） mm to （2.4±0.4） mm （P〈0.001） and from （3.3±0.3） mm to （2.6±0.5） mm （P〈0.001）, respectively. Minimal and maximal diameters of MB derived from MSCT were significantly smaller than those from IVUS （（2.4±0.4） mm vs （2.6±0.5） mm, P〈0.05 and （2.9±0.3） mm vs （3.3±0.3） mm, P〈0.05）, respectively. Conclusions MSCT offers a reliable non-invasive method for MB in LAD and atherosclerosis diagnosis with diagnostic accuracy comparable with invasive IVUS.
文摘Background There are few reports of quantitative and qualitative measuring of left main coronary artery （LMCA） plaques by multislice computed tomography coronary angiography （MSCTA）, especially when compared with intravascular ultrasound （IVUS） as reference standard. The aim of this study was to evaluate the use of 64-MSCTA in the diagnosis of LMCA disease, and the accuracy of MSCTA in the quantitative and qualitative assessment of the LMCA lesion as compared with IVUS.Methods A total of 91 patients （53 men, 38 women, mean age （64.78±9.19） years） were examined by 64-MSCTA and IVUS. Compared with the IVUS, the sensitivity, specificity, positive and negative predictive values （PPV and NPV） of the MSCTA on the diagnosis of LMCA diseases were calculated. Also, kappa index （K） for the agreement between MSCTA and IVUS was calculated. Minimal lumen area （MLA）, external elastic membrane cross-sectional area （EEM-CSA） and plaque burden were measured by two blinded and independent operators on MSCTA cross-sectional reconstruction and compared with the parameters measured from IVUS by manually tracing. The CT value of soft, fibrous and calcific plaques was measured using IVUS classification of the plaques.Results The sensitivity, specificity, PPV and NPV of MSCTA for detecting LMCA plaques were 93.1%, 84.2%, 95.7%, 76.2%, respectively. Kappa index （K=0.744, P〈0.001） indicated excellent agreement between MSCTA and IVUS. The Pearson index between MLA on IVUS and MLA on MSCTA was 0.815 （P 〈0.01）. The Pearson index of plaque burden and EEM-CSA between IVUS and MSCTA was 0.736 and 0.740 respectively （both P 〈0.01）. The CT value of soft plaque, fibrous plaque and calcific plaque compared with IVUS were （52.52±15.71） HU, （108.32±43.44） HU and （604.16±377.67） HU （P〈0.001）. Receiver operating characteristic curve analysis of CT value of non-calcific plaques for predicting soft plaques showed the cutpoint was 54.35 HU, with a sensitivity of 83.3% and specificity of 94.4%. Conclusions Sixty-four section MSCTA is an effective diagnostic tool for the detection of LMCA plaques with higher sensitivity and specificity. The correlation of quantitative and qualitative analysis between MSCTA and IVUS was excellent. The CT value of plaques can help the diagnosis of plaque composition.
文摘Conventional ultrasound （US） is the most widely used imaging modality in routine clinical practice worldwide. The limitations of conventional ultrasound in the detection of aortic lesions versus multi-slice computed tomography angiography （MS-CTA） are well known.
基金This study was supported in partbyagrant from the Doctor Foundation of ScienceandTechnologyBureauofHebeiProvince (No .0 0 5 42 0 0D -15 ) .
文摘Background Multislice helical computed tomography (MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy of ventricular volume as measured by MSCT.Methods Fourteen human left ventricular (LV) and 15 right ventricular (RV) casts were scanned by MSCT. A series of LV and RV short-axis images were reconstructed later with slice thickness of 2.0 mm, 3.5 mm, 5.0 mm, 7.0 mm, and 10.0 mm. Ventricular volume was calculated by the multislice tomographic Simpson’s method. True LV and RV cast volumes were determined by water displacement. Results Both calculated LV and RV volumes correlated highly with the corresponding true volumes (all r>0.95, P<0.01). But with slice thickness from 2.0 mm to 10.0 mm, MSCT scanning overestimated the corresponding true volume by (3.21±5.95) ml to (12.58±8.56) ml for LV and (10.22±8.45) ml to (23.91±12.24) ml for RV (all P<0.01). There was a very high correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements (r=0.998 and 0.996, P<0.01, respectively). However, when slice thickness was reduced to 5.0 mm, the overestimation for both LV and RV volume measurements became nonsignificant for slice thickness from 2.0 mm to 5.0 mm. Conclusions Both LV and RV volumes can be accurately estimated by MSCT. Thinner slice has more accurate calculated volume. However, 5.0 mm slice thickness is thin enough for an accurate measurement of LV or RV volume.
文摘Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compared to invasive coronary angiography.Diagnostic performance of coronary CT angiography has been significantly improved with the technological developments in multislice CT scanners from the early generation of 4-slice CT to the latest 320-slice CT scanners.Despite the promising diagnostic value,coronary CT angiography is still limited in some areas,such as inferior temporal resolution,motion-related artifacts and high false positive results due to severe calcification.The aim of this review is to present an overview of the technical developments of multislice CT and diagnostic value of coronary CT angiography in coronary artery disease based on different generations of multislice CT scanners.Prognostic value of coronary CT angiography in coronary artery disease is also discussed,while limitations and challenges of coronary CT angiography are highlighted.
文摘AIM: To investigate the research directions of coronary computed tomography (CT) angiography in the diagnosis of coronary artery disease (CAD) based on a systematic review of the literature.METHODS: A search of articles on coronary CT angiography in the diagnosis of CAD was performed during a 6-year-period between 2005 and 2010 from f ive main radiology journals namely, Radiology, American Journal of Roentgenology, European Radiology, European Journal of Radiology and British Journal of Radiology. Analysis of the references was focused on the research directions of coronary CT angiography with regard to the type of studies in terms of diagnostic value, application of dose-reduction strategies and resultant effective radiation doses with use of these techniques.RESULTS: One hundred and forty two studies were identified which met the selection criteria and were included in the analysis. 64-slice CT (single source anddual-source CT) dominated 78% of the coronary CT angiography studies. Prior to 2007, research was focused on the diagnostic value of coronary CT angiography, but since 2008 more attention has been paid to radiation dose reduction. Radiation dose was reported in 64 studies, representing 45% of total studies published in the f ive radiology journals. Various dose-saving strategies have been implemented and prospective electrocardiography-triggering and high pitch techniques were found to be the most effective approaches for radiation dose reduction, with the corresponding mean effective dose being 3.5 ± 1.9 mSv and 1.7 ± 0.6 mSv, respectively.CONCLUSION: This review shows that the current research in coronary CT angiography has shifted from the previous focus on diagnostic accuracy in CAD to more emphasis on radiation dose reduction.
文摘Atrial fibrillation is the most common arrhythmia and in symptomatic patients with a drug-refractory form,catheter ablation aimed at electrically disconnecting the pulmonary veins(PVs) has proved more effective than use of antiarrhythmic drugs in maintaining sinus rhythm during follow-up.On the other hand,this ablation procedure is complex,requires specific training and adequate clinical experience.A main challenge is represented by the need for accurate sequential positioning of the ablation catheter around each veno-atrial junction to deliver point-by-point radiofrequency energy applications in order to achieve complete and persistent electrical disconnection of the PVs.Imaging integration is a new technology that enables guidance during this procedure by showing a three-dimensional,pre-acquired computed tomography or magnetic resonance image and the relative real-time position of the ablation catheter on the screen of the electroanatomic system.Reports in the literature suggest that imaging integration provides accurate visual information with improvement in the procedure parameters and/or clinical outcomes of the procedure.
文摘Thin cap fibroatheromas(TCFAs) are thought to be the most common underlying substrate in patients suffering acute coronary thrombotic events.Recently,an interesting association between TCFAs and a particular depot of visceral fat called epicardial adipose tissue(EAT) has been suggested.In this article,we discuss some basic and clinical aspects of this association and then briefly review some of the pathophysiological characteristics attributed to EAT that explain why this particular depot of fat has been attracting the attention of the cardiological scientific community in recent years.Finally we discuss the value of optical coherence tomography in the diagnosis of TCFAs and the role of multislice computed tomography to assess EAT.
文摘Coronary computed tomography(CT)angiography has been increasingly used in the diagnosis of coronary artery disease due to improved spatial and temporal resolution with high diagnostic value being reported when compared to invasive coronary angiography.Diagnostic performance of coronary CT angiography has been significantly improved with the technological developments in multislice CT scanners from the early generation of 4-slice CT to the latest 320-slice CT scanners.Despite the promising diagnostic value,coronary CT angiography is still limited in some areas,such as inferior temporal resolution,motion-related artifacts and high false positive results due to severe calcification.The aim of this review is to present an overview of the technical developments of multislice CT and diagnostic value of coronary CT angiography in coronary artery disease based on different generations of multislice CT scanners.Prognostic value of coronary CT angiography in coronary artery disease is also discussed,while limitations and challenges of coronary CT angiography are highlighted.
文摘With the introduction of 64- and post-64 slice computed tomography(CT)technology,coronary CT angiography has been increasingly used as a less invasive modality for the diagnosis of coronary artery disease.Despite its high diagnostic value and promising results compared to invasive coronary angiography,coronary CT angiography is associated with high radiation dose,leading to potential risk of radiation-induced cancer.A variety of dose-reduction strategies have been reported recently to reduce radiation dose with effective outcomes having been achieved.This article presents an overview of the various methods currently used for radiation dose reduction.
文摘Background:Although computed tomography coronary angiography (CTCA) can identify coronary stenosis,little data exists on the ability of multislice computed tomography (MSCT) to detect myocardial perfusion defects at rest.Methods:In 33 patients with diagnosed or suspected coronary artery disease (CAD),CTCA using retrospective electrocardiography (ECG) gating at rest and invasive coronary angiography (ICA) was performed.The 2D myocardial images were reconstructed in diastolic and systolic phases using the same raw data for CTCA.CT values of the myocardium were used as an estimate of myocardial enhancement,which were shown by color mapping.Myocardial ischemia was defined as a pattern of transient endocardial hypo-enhancement at systole and normal enhancement at diastole.The results of ICA were taken as the reference standard.Results:When a diameter reduction of more than 50% in ICA was used as diagnostic criteria of CAD,the sensitivity,specificity,positive predictive value (PPV),and negative predictive value (NPV) of CT first-pass myocardial perfusion imaging (MPI) at rest were 0.85,0.67,0.92,and 0.50 per patient,respectively,and 0.58,0.93,0.85,and 0.76 per vessel,respectively.Conclusions:CT first-pass MPI at rest could detect CAD patients,which could become a practical and convenient way to detect ischemia,consequently offering the ability for MSCT to act as a "one stop shop" for the diagnosis of CAD.
