OBJECTIVE: To assess the effects of iterative model reconstruction (IMR) on image quality for demonstrating non-calcific high-risk plaque characteristics of coronary arteries. MATERIALS AND METHODS: This study included 66 patients (53 men and 13 women; aged 39–76 years; mean age, 55 ± 13 years) having single-vessel disease with predominantly non-calcified plaques evaluated using prospective electrocardiogram-gated 256-slice CT angiography. Paired image sets were created using two types of reconstruction: hybrid iterative reconstruction (HIR) and IMR. Plaque characteristics were compared using the two algorithms. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the images and the CNR between the plaque and adjacent adipose tissue were also compared between the two reformatted methods. RESULTS: Seventy-seven predominantly non-calcified plaques were detected. Forty plaques showed napkin-ring sign with the IMR reformatted method, while nineteen plaques demonstrated napkin-ring sign with HIR. There was no statistically significant difference in the presentation of positive remodeling, low attenuation plaque, and spotty calcification between the HIR and IMR reconstructed methods (all p > 0.5); however, there was a statistically significant difference in the ability to discern the napkin-ring sign between the two algorithms (χ2 = 12.12, p < 0.001). The image noise of IMR was lower than that of HIR (10 ± 2 HU versus 12 ± 2 HU; p < 0.01), and the SNR and CNR of the images and the CNR between plaques and surrounding adipose tissues on IMR were better than those on HIR (p < 0.01). CONCLUSION: IMR can significantly improve image quality compared with HIR for the demonstration of coronary artery and atherosclerotic plaques using a 256-slice CT.
Adipose Tissue ; Angiography ; Atherosclerosis ; Coronary Artery Disease ; Coronary Vessels ; Female ; Humans ; Image Processing, Computer-Assisted ; Male ; Methods ; Multidetector Computed Tomography ; Noise ; Plaque, Atherosclerotic ; Prospective Studies ; Signal-To-Noise Ratio

PURPOSE: This clinical pilot study was performed to determine the effectiveness of dual-energy cone-beam computed tomography (DE-CBCT) in measuring bone mineral density (BMD).MATERIALS AND METHODS: The BMD values obtained using DE-CBCT were compared to those obtained using calibrated multislice computed tomography (MSCT). After BMD calibration with specially designed phantoms, both DE-CBCT and MSCT scanning were performed in 15 adult dental patients. Three-dimensional (3D) Digital Imaging and Communications in Medicine data were imported into a dental software program, and the defined regions of interest (ROIs) on the 3-dimensional surface-rendered images were identified. The automatically-measured BMD values of the ROIs (g/cm³), the differences in the measured BMD values of the matched ROIs obtained by DE-CBCT and MSCT 3D images, and the correlation between the BMD values obtained by the 2 devices were statistically analyzed.RESULTS: The mean BMD values of the ROIs for the 15 patients as assessed using DE-CBCT and MSCT were 1.09±0.07 g/cm³ and 1.13±0.08 g/cm³, respectively. The mean of the differences between the BMD values of the matched ROIs as assessed using DE-CBCT and calibrated MSCT images was 0.04±0.02 g/cm³. The Pearson correlation coefficient between the BMD values of DE-CBCT and MSCT images was 0.982 (r=0.982, P<0.001).CONCLUSION: The newly developed DE-CBCT technique could be used to measure jaw BMD in dentistry and may soon replace MSCT, which is expensive and requires special facilities.
Adult ; Bone Density ; Calibration ; Cone-Beam Computed Tomography ; Dentistry ; Humans ; Jaw ; Methods ; Miners ; Multidetector Computed Tomography ; Pilot Projects

BACKGROUNDRetroperitoneal fibrosis (RPF) and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography (MDCT).

METHODSThe 42 consecutive patients were included in this retrospective review, including 19 RPF patients (45.2%; including 13 males and 6 females; mean age: 56.7 ± 6.2 years) and 23 patients with lymphoma (54.8%; including 14 males and 9 females; mean age: 57.4 ± 12.3 years). An array of qualitative computed tomography (CT) features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated.

RESULTSMean ages between patients with RPF and lymphoma were not significantly different (56.7 ± 6.2 years vs. 57.4 ± 12.3 years P = 0.595). Compared to those in patients with lymphoma, homogeneous enhancement (65.2% vs. 94.7%, P = 0.027) and pelvic extension (52.2% vs. 89.5%, P = 0.017) were significantly more common while the involvement of additional nodes (78.3% vs. 5.3%, P < 0.001), suprarenal extension (60.9% vs. 15.8%, P = 0.004), and aortic displacement (43.5% vs. 5.3%, P = 0.006) were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients (3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P < 0.001). The attenuation values in three phases were not significantly different between patients with RPF and lymphoma. Inter-reader concordance for subjective features ranged from very good to excellent (range: 85.7-100.0%).

CONCLUSIONSThis study showed that MDCT can help differentiate between untreated RPF and lymphoma on the basis of qualitative CT features and lesion sizes. Differentiating RPF from lymphoma on the basis of attenuation values in the precontrast, arterial, and portal phases was difficult to accomplish.

Aged ; Diagnosis, Differential ; Female ; Humans ; Lymphoma ; diagnosis ; Male ; Middle Aged ; Multidetector Computed Tomography ; methods ; ROC Curve ; Retroperitoneal Fibrosis ; diagnosis ; Retrospective Studies

Objective To evaluate the image quality and radiation exposure in multidetector computed tomography (MDCT) with automated topogram-based tube potential selection,compared to fixed tube potential,in patients with solid pancreatic lesions. Methods The preoperative pancreatic dual-source CT images of 113 patients who were confirmed as solid pancreatic lesions by postoperative pathology in the Peking Union Medical College Hospital from January 2014 to August 2016 were retrospectively analyzed.Among them,53 patients were examined on fixed tube potential at 120 kV,and tube current was automatically modulated (group 1). Sixty patients underwent topogram-based automatic tube potential selection (Tube voltage step:90,100 kV) and automated mA modulation (group 2). Two experienced radiologists measured the body sizes,assessed subjective and objective image quality of arterial phase and portal phase,and recorded radiation parameters including CT dose index volume (CTDI) and dose-length product (DLP). Results Of 60 patients in group 2,45 patients were scaned at 90 kV,15 patients were scaned at 100 kV.The average body diameter [(287±24) mm] in 90 kV group was significantly lower than that [(328±22) mm] in 100 kV group(t=0.731,P=0.0008). The mean CTDI[(3.9±1.0) mGy] in group 2 was significantly lower than in group 1 [(9.0±1.9) mGy],reduced by 56.7% (t=17.5,P=0.0003). The average DLP [(109±38) mGy·cm] in group 2 was significantly lower than that in group 1 [(276±83) mGy·cm],reduced by 60.5% (t=14.0,P=0.0007). In group 2,the standard deviations of images background noise in arterial and portal phase were (6.4±0.9) and (6.4±1.0)HU,respectively,which were significantly higher than those in group 1 [(5.6±1.4)HU,t=-3.757,P=0.0003;(5.5±1.4)HU,t=-3.828,P=0.0006]. In group 2,the signal to noise ratios of pancreatic lesions, abdominal aorta in arterial phase and pancreatic lesions, the portal vein in portal phase were 18.8±9.3,76.0±19.3 and 17.4±6.7,33.1±7.2,which were significantly higher than those in group 1 (13.1±8.7,t=-3.379,P=0.001;56.5±22.6,t=-2.268,P=0.025;14.1±8.1,t=-2.283,P=0.024;28.9±8.8,t=-2.613,P=0.009). Conclusion Compared with fixed tube voltage on the second-generation dual-source CT techniques,topogram-based automatic tube potential selection on third-generation dual-source CT can reduce radiation dose without decreasing image quality in imaging solid pancreatic lesions.
Humans ; Multidetector Computed Tomography ; methods ; Pancreas ; diagnostic imaging ; pathology ; Radiation Dosage ; Retrospective Studies ; Signal-To-Noise Ratio

Although pediatric pulmonary thromboembolism is historically believed to be rare with relatively little information available in the medical literature regarding its imaging evaluation, it is more common than previously thought. Thus, it is imperative for radiologists to be aware of the most recent advances in its imaging information, particularly multidetector computed tomography (MDCT), the imaging modality of choice in the pediatric population. The overarching goal of this article is to review the most recent updates on MDCT diagnosis of pediatric pulmonary thromboembolism.
Humans ; Image Processing, Computer-Assisted ; Multidetector Computed Tomography/instrumentation/*methods ; Pediatrics ; Pulmonary Embolism/physiopathology/*radiography ; Risk Factors

We report multidetector computed tomography (MDCT) and cardiac magnetic resonance (CMR) findings of a 34-year-old female with isolated left ventricular apical hypoplasia. The MDCT and CMR scans displayed a spherical left ventricle (LV) with extensive fatty infiltration within the myocardium at the apex, interventricular septum and inferior wall, anteroapical origin of the papillary muscle, right ventricle wrapping around the deficient LV apex, and impaired systolic function. MDCT visualized morphologic and also functional findings of this unique cardiomyopathy.
Adult ; Cardiomyopathy, Dilated/*radiography ; Female ; Heart Ventricles/*radiography ; Humans ; Hypoplastic Left Heart Syndrome/*radiography ; Imaging, Three-Dimensional/*methods ; Multidetector Computed Tomography/*methods ; Myocardium/pathology

OBJECTIVETo investigate the feasibility and reliability on the quantitative evaluation of Colles' fracture by multislice CT (MSCT) multiplanner reconstruction (MPR).

METHODSA total of 36 patients with Colles' fracture from July 2011 to July 2014 were investigated in this study. There were 11 males and 25 females with a mean age of (42.5 ± 5.4) years old (ranged 35 to 72 years). All the patients underwent anteroposterior and lateral X-ray films and MSCT scans on wrist joints within 2 days after trauma. Images were sent to the workstation through picture archiving and conserving system (PACS). One associate chief physician independently and respectively measured the dorsal intercalation depth of distal fracture block, palmar angle and dislocation degree of wrist articular surface collapse on anteroposterior and lateral X-ray film and MSCT-MPR. The time interval between the two measurements was 2 weeks. All the data between the first and second measurement on X-ray and MPR and the mean value between the X-ray and MPR was examined with paired t-test. The pearson analyzed their correlation.

RESULTSAmong the 35 cases, 35 cases of palmar angle, 21 cases of intercalation depth and 16 cases of dislocation of wrist articular surface collapse could be measured on both X-ray and MPR. For the above parameters, the first measurement results were (12.5 ± 3.6)°, (4.5 ± 2.1) mm, (3.7 ± 1.6) mm and the second measurement results were (4.8 ± 2.2)°, (6.4 ± 3.6) mm, (2.5 ± 1.2) mm on X-ray films respectively. The first measurement results on MPR were (14.5 ± 5.3)°, (4.2 ± 1.2) mm, (5.7 ± 2.3) mm, and the results were (13.2 ± 2.6)°, (4.7 ± 2.2) mm, (4.6 ± 2.1) mm for the second measurement respectively. The three parameters between the first and second measurement on plain film had statistical difference and low correlation (r = 0.681, 0.640, 0.345, P < 0.05). The data between the first and second measurement on MPR showed that the dislocation degree of wrist articular surface collapse had statistical difference (P < 0.05) and no statistical significance was found for the other two parameters (P > 0.05), with the moderate correlation (r = 0.954, 0.854, 0.642). The three parameters had low or moderate correlation with each other on X-ray (r = 0.454, 0.532, 0.378, P < 0.05), compared with the mean value on MPR.

CONCLUSIONUsing MSCT MPR images may carry on the multiple parameter measurement of Colles fracture, to make quantitative evaluation, and repeated measurement is better reliability.

Adult ; Aged ; Colles' Fracture ; diagnostic imaging ; Feasibility Studies ; Female ; Humans ; Image Processing, Computer-Assisted ; Male ; Middle Aged ; Multidetector Computed Tomography ; methods

BACKGROUNDMultislice computed tomography (MSCT) coronary angiography (CAG) is a noninvasive technique with a reported high diagnostic accuracy for coronary artery disease (CAD). Women, more frequently than men, are known to develop atypical angina symptoms. The purpose of this study was to investigate whether the diagnostic accuracy of MSCT in women with atypical presentation differs from that in men.

METHODSWe enrolled 396 in-hospital patients (141 women and 255 men) with suspected or proven CAD who successively underwent both MSCT and invasive CAG. CAD was defined as any coronary stenosis of ≥50% on conventional invasive CAG, which was used as the reference standard. The patients were divided into typical and atypical groups based on their symptoms of angina pectoris. The diagnostic accuracy of MSCT, including its sensitivity, specificity, negative predictive value, and positive predictive value (PPV), was calculated to determine the usefulness of MSCT in assessing stenoses. The diagnostic performance of MSCT was also assessed by constructing receiver operating characteristic (ROC) curves.

RESULTSThe PPV (91% vs. 97%, χ2 = 5.705, P < 0.05) and diagnostic accuracy (87% vs. 93%, χ2 = 5.093,P< 0.05) of MSCT in detecting CAD were lower in women than in men. Atypical presentation was an independent influencing factor on the diagnostic accuracy of MSCT in women (odds ratio = 4.94, 95% confidence intervals: 1.16-20.92, Walds = 4.69, P < 0.05). Compared with those in the atypical group, women with typical angina pectoris had higher PPV (98% vs. 74%, χ2 = 17.283. P < 0.001), diagnostic accuracy (93% vs. 72%, χ2 = 9.571, P < 0.001), and area under the ROC curve (0.91 vs. 0.64, Z = 2.690, P < 0.01) in MSCT diagnosis.

CONCLUSIONSAlthough MSCT is a reliable diagnostic modality for the exclusion of significant coronary artery stenoses in all patients, gender and atypical symptoms might have some influence on its diagnostic accuracy.

Aged ; Angina Pectoris ; diagnosis ; Coronary Angiography ; methods ; Coronary Artery Disease ; diagnosis ; Female ; Humans ; Male ; Middle Aged ; Multidetector Computed Tomography ; methods ; Predictive Value of Tests ; ROC Curve ; Sensitivity and Specificity

INTRODUCTIONThis study aimed to assess the ability of contrast-enhanced computed tomography (CECT) to detect active abdominopelvic haemorrhage in patients with blunt trauma, as compared to digital subtraction angiography (DSA).

METHODSIn this retrospective study, patients who underwent DSA within 24 hours following CECT for blunt abdominal and/or pelvic trauma were identified. The computed tomography (CT) trauma protocol consisted of a portal venous phase scan without CT angiography; delayed phase study was performed if appropriate. All selected CECT studies were independently reviewed for the presence of active extravasation of contrast by two radiologists, who were blinded to the DSA results. Fisher's exact test was used to correlate the presence of extravasation on CT with subsequent confirmed haemorrhage on DSA.

RESULTSDuring the eight-year study period, 51 patients underwent CECT prior to emergent DSA for abdominal or pelvic trauma. Evidence of active extravasation of contrast on CECT was observed in 35 patients and active haemorrhage was confirmed on DSA in 31 of these patients; embolisation was performed in all 31 patients. Two patients who were negative for active extravasation of contrast on CECT but positive for active haemorrhage on DSA had extensive bilateral pelvic fractures and haematomas. The sensitivity, specificity, and positive and negative predictive values of CECT in detecting active abdominopelvic haemorrhage, as compared to DSA, were 93.9%, 77.8%, 88.6% and 87.5%, respectively.

CONCLUSIONWhen compared with DSA, dual-phase CECT without CT angiography shows high sensitivity and positive predictive value for the detection of active haemorrhage in patients with blunt abdominopelvic trauma.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Angiography, Digital Subtraction ; Female ; Humans ; Male ; Middle Aged ; Multidetector Computed Tomography ; Observer Variation ; Pelvic Bones ; Pelvis ; injuries ; Radiology ; methods ; Retrospective Studies ; Wounds, Nonpenetrating ; diagnostic imaging ; Young Adult

A case of a stillbirth with lethal type II osteogenesis imperfecta (OI) was reported. The fetus had skull fractures and craniocerebral injuries during pregnancy. Postmortem multi-sliced computed tomography (MSCT) and 3D-reconstruction were performed, followed by a medico-legal autopsy. The autopsic findings showed the typical features of type II OI, including a soft calvarium, deformed extremities, flexed and abducted hips, and uncommon features, such as white sclera, coxa vara, absence of several bones and organs, a cleft lip, and asymmetric ears. The radiologic images revealed such anomalies and variations as a cleft palate, mandibular dysplasia, spina bifida, costa cervicalis, and fusion of the ribs and vertebrae, which were difficult to detect during conventional autopsy. The paper investigated the classification, causative mutation, cause of death, and the differentiation of OI from child abuse, coming to a conclusion that OI knowledge can be of great importance to forensic pathologists and that the merits of postmortem MSCT should be emphasized in forensic pathologic examinations.
Autopsy ; Child ; Death ; Fatal Outcome ; Female ; Fetus ; Forensic Pathology ; Humans ; Infant, Newborn ; Multidetector Computed Tomography/methods* ; Osteogenesis Imperfecta/physiopathology* ; Pregnancy ; Ribs ; Skull/pathology*