Purpose To evaluate the correlations between high resolution CT (HRCT) findings and IASLC/ATS/ERS pathological classification of ground glass nodule (GGN). Materials and Methods 121 patients with confirmed GGN were selected, and divided into benign group (22 cases), PIL group (21 cases), microinvasive carcinoma group (26 cases) and invasive carcinoma group (52 cases), then the imaging, pathology and prognosis data of patients with pulmonary GGN were reviewed, and the differences among GGN of different pathological types were analyzed.Results Maximum diameter, margin, vacuole sign, solid component, shape and blood vessels through of GGN were significantly different among the four groups (χ2=9.945-31.068,P<0.05). Maximum diameter and margin were significantly different between invasive adenocarcinoma and other groups (P<0.008); vacuole sign of the benign group was significantly different with other groups (P<0.008); the existence of solid component and shape were significantly different between invasive adenocarcinoma and minimally invasive adenocarcinoma (P<0.008); there was significant difference of blood vessels through between invasive adenocarcinoma and benign lesions (P<0.008). Among the 121 lesions, no metastasis except one invasive adenocarcinoma case complicated with distant metastasis.Conclusion Maximum diameter of GGN greater than 16.35 mm, with spiculation or lobulation represent invasive adenocarcinoma; vacuole sign within the GGN represent malignancy; with solid component and irregular shape can be used to identify invasive adenocarcinoma from minimally invasive adenocarcinoma; while blood vessels through can be used to identify invasive adenocarcinoma from benign lesions; the prognosis of GGNs is well with only 0.83% probability of distant metastasis.

Purpose To evaluate the correlation between carotid elasticity and age using electrocardiogram (ECG)-gated multi-detector CT angiography (MDCTA).Materials and Methods ECG-gated multiple phases MDCTA was performed on 34 vascular health subjects. Cross-section of the internal carotid artery (ICA), carotid bulb (CB) and common carotid artery (CCA) were measured at different phases. Carotid elasticity at ICA (EICA), CB (ECB) and CCA (ECCA) was calculated based on the carotid cross-sectional area changes and pulse pressure (PP).Results The EICA, ECB and ECCA showed significantly negative linear correlation with age (r=-0.73,-0.74 and-0.64,P<0.01). Conclusion The ECG-gated MDCTA is a novel method to evaluate carotid elasticity quantitatively and reliably. Carotid elasticity decreases with aging in vascular health population.

Purpose To explore the commonality and disparity between 64-slice CT coronary artery imaging and coronary angiography (CAG) for the diagnosis of coronary heart disease, and to provide evidence for clinical diagnosis.Materials and Methods Forty-nine patients with suspected coronary heart disease (CHD) underwent both 64-slice CT coronary artery imaging and conventional coronary artery angiography, all available coronary segments were evaluated using a 15-segment modified AHA classification, and the results of both methods were compared and analyzed.Results 493 segments of coronary artery were evaluated, results of 29 segments were incongruent between 64-slice CT coronary artery imaging and CAG. With CAG as the gold standard, the sensitivity, specificity, positive predictive value and negative predictive value of CT coronary artery imaging for the diagnosis of coronary artery stenosis were 91.6%, 95.4%, 91.0% and 95.7% respectively.Conclusion There is a high consistency between 64-slice CT coronary artery imaging and CAG for diagnosing CHD, 64-slice CT coronary artery imaging can be used to evaluate the nature of artery plaque, but it is inferior to CAG in diagnosing small angiostenosis.

Purpose To observe the characteristics of coronary artery lesion in patients with unstable angina pectoris (UAP) and stable angina pectoris (SAP) using virtual histology intravascular ultrasound (IVUS-VH).Materials and Methods A total of 199 patients with angina pectoris were enrolled and divided into SAP group (101 cases) and UAP group (98 cases) according to clinical symptoms, ECG and myocardial enzyme level. All the patients underwent coronary angiography to determine the criminals vessels, grayscale intravascular ultrasound was used to measure and compare the external elastic membrane area (EEMA), lumen cross-sectional area (lumen CSA), plaque area (PA), plaque burden (PB), remodeling index (RI), plaque eccentricity index (EI) of the criminals vessels. IVUS-VH method was used to measure and compare the area and percentage of calcified tissue,fibrous tissue, lipid tissue and necrotic tissue in the plague components of the criminals vessels between the two groups.Results There was no significant difference (t=1.392,-0.345, 1.921, 0.378 and 0.857,P>0.05) of EEMA, lumen CSA, PA, EI and RI measured at the location with smallest lumen area between the two groups. Necrotic core area and percentage of lesion composition in UAP group was significantly higher than that in SAP group (t=2.361,P<0.05). There was no statistically significant difference (t=1.045, 1.884 and 0.787,P>0.05) between the two groups on the area of fiber, lipid and calcification. On the distribution of plaque components, fibrous plaque area percentage of UAP group was lower than that in SAP group (t=-2.418, P<0.05), while the necrotic core area was significantly higher than SAP group (t=2.602, P<0.05), there was no significant difference (t=-0.551 and 0.085,P>0.05) between the two groups on lipid and calcification area.Conclusion Necrotic core area and percentage of plaque composition in the UAP group is larger than the other group. Criminals lesions are more unstable and more easily to be complicated with acute cardiovascular events.

Purpose To assess the clinical application of non-contrast-enhanced MR angiography (NCE-MRA) using flow sensitive dephasing (FSD) prepared steady-state free precession (SSFP) for displaying hand arteries of patients with rheumatoid arthritis. Materials and Methods Twenty-two patients with rheumatoid arthritis were recruited in this study. All the patients undertook hand NCE-MRA and three-dimensional dynamic CE-MRA on a 1.5T MR scanner. The informed consent was obtained from each subject. Image quality was assessed independently by two experienced radiologists at three arterial segments (wrist arteries, palm arteries, andfinger arteries) with a four-point scale. Signal to noise ratio (SNR), contrast to noise ratio (CNR), and vessel sharpness were evaluated by a magnetic resonance physicist. The results and image quality were statistically compared between the two MRA techniques.Results Twenty-two patients of 24 hands successfully underwent NCE-MRA and CE-MRA scan. Among 72 vascular segments, 69 segments of NCE-MRA were diagnostic, which was higher than that of CE-MRA (96% vs 83%,P<0.05). Otherwise, the image quality, SNR, CNR and vessel sharpness of NCE-MRA were all superior to those of CE-MRA (P<0.05).Conclusion NCE-MRA using FSD-prepared SSFP allows clear depiction of the hand arterial tree, and the image quality is superior to that of dynamic CE-MRA. It is a potential tool for evaluating the disease of hand arteries.

Purpose To analysis the CT manifestations of acinar cell carcinomas of the pancreas (ACCs) in order to know more about its CT signs. Materials and Methods The plain and enhanced CT findings of 9 patients with AACs proved pathologically were analyzed retrospectively. Results The main image ifndings of the patients were as follows:①the pancreas grew with exophytic dilatability;②they tended to be large (average diameter was 4.7 cm), with round or oval shape; ③ the lesions showed hypodense on enhanced scan and the solid areas showed slight enhancement in the arterial phase compared with normal pancreas;④most lesions had uniform or partial thin enhanced ring;⑤most lesions demonstrated cystic or necrotic;⑥few had pancreatic/biliary ductal dilatation and peripancreatic involvement;⑦few showed internal calciifcation or intratumoral hemorrhage. Conclusion Plain CT scan and enhanced scan are signiifcant in locating and differentiating acinar cell carcinoma of the pancreas.

Purpose To quantitatively analyze the blood perfusion parameters after kidney transplantation with acute and chronic rejection by using contrast-enhanced ultrasonography (CEUS), in order to provide rapid assessment for rejection prognosis. Materials and Methods Thirty-one patients with kidney transplantation were followed up and divided into three groups according to clinical symptoms and graft biopsy results:normal group (n=6), acute rejection group (n=12) and chronic rejection group (n=13). CEUS was carried out to assess renal microcirculation perfusion. Results CEUS showed that the normal renal parenchyma was enhanced homogeneously whilst the rejected parenchyma was enhanced heterogeneously. The differences of area under the curve among the three groups was statistically signiifcant (F=37.102, P<0.01), with normal group >chronic rejection group > acute rejection group. The peak intensity in normal group was higher than that in acute rejection group (P<0.01), but it showed no difference with that in chronic group. In acute and chronic rejection groups, the arrival time and the time to peak intensity in interlobar artery and cortex were all later than those in normal group (P<0.05). The ascending slope of TIC in segmental artery, interlobar artery and cortex in the two rejection groups was both signiifcantly less than that in normal group. Conclusion CEUS is a valuable diagnostic tool in the evaluation of microcirculation perfusion in kidney graft, and can provide important reference for the prognosis of acute and chronic rejection after kidney transplantation.

PurposeTo explore CT and MRI findings of pigmented villonodular synovitis (PVNS) of spine, and to improve the preoperative diagnosis.Materials and MethodsCT and MRI findings of 7 cases of PVNS of spine confirmed by surgery and pathology were retrospectively analyzed. Seven cases underwent CT scan and 5 of them underwent MRI scan. The location of the lesions, tumor size, shape, density (signal), bone destruction and enhanced features were analyzed.ResultsExcept one case with small lesion, the remaining 6 cases showed lobulated soft tissue masses centering at the facet joint area, with lytic, expansive bone destruction. On CT images (n=7), 3 cases showed the masses density similar to that of the surrounding muscles, and 4 cases showed the tumor density slightly lower than that of the surrounding muscles. On MRI images (n=5), 1 small lesion demonstrated low signal at the peripheral, 1 lesion was isointensity without obvious low-density in it, 3 cases showed characteristic multiple visible low signal nodules in the lesions.ConclusionThe possibility diagnosis of the PVNS should be considered when spinal lesions are characterized by osteolytic bone destruction centering at facet joints and soft tissue masses with distinctive MR signals.

PurposeTo prospectively investigate the effect of gadolinium contrast media on the quality of intravoxel incoherent motion (IVIM) MRI images and the quantification of corresponding parameters for abdominal solid organs, and to explore the appropriate time for abdominal IVIM scan.Materials and MethodsTwenty patients underwent the same abdominal IVIM scan before and after gadolinium contrast administration. The signal-to-noise ratio (SNR) of liver, spleen, pancreas and kidneys were measured on diffusion-weighted imaging (DWI) images at b=50 s/mm2, 300 s/mm2 and 800 s/mm2. SNR and contrast-to-noise ratio (CNR) of hepatocellular carcinoma (HCC) (n=16) were also calculated. Apparent diffusion coefficient (ADC) value and IVIM parameters including pure diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion fraction (f) of liver, spleen, kidneys parenchyma and HCC were measured and compared. ResultsSNR of liver on post-contrast DWI at b=50 s/mm2 were significantly lower than that of pre-contrast (t=2.397,P<0.05). CNR of HCC increased significantly on b=300 s/mm2 DWI images after contrast (t=-3.380,P<0.01). SNR of kidneys on DWI of any b value decreased after contrast administration (Z=-2.675--2.201,P<0.05). SNR of spleen, pancreas and HCC were not statistically different between pre-contrast and post-contrast images (t orZ=-1.324-1.104,P>0.05). As for IVIM parameters, only ADC and D values of kidneys demonstrated a significant reduction after contrast (ADC:t=3.569,P<0.01; D:Z=-3.053,P<0.01). No significant differences were detected for all parameters of liver, spleen and HCC between pre-contrast and post-contrast images (t=-1.102-1.689,P>0.05). ConclusionAdministration of gadolinium contrast media may result in decrease of SNR of liver on low b value DWI and SNR of kidneys at any b value, but it increases CNR of hepatic lesions on medium b value DWI. Administration of gadolinium contrast media does not make a significant effect on SNR of spleen, pancreas and hepatic lesions. Furthermore, ADC and D values of kidneys decrease after administration of gadolinium contrast media. There is no significant influence of contrast medium on DWI and IVIM parameters of liver, hepatic lesions and spleen.

PurposeTo determine the feasibility and accuracy of dual source CT (DSCT) in assessing myocardial delayed-enhancement and left ventricular wall thickness of hypertrophic cardiomyopathy (HCM) in comparison with cardiac magnetic resonance (CMR).Materials and MethodsEighty patients with HCM confirmed by clinical diagnosis were enrolled in the study. DSCT images and CMR images were acquired at the arterial and lag phases. According to 17-segment model provided by American Heart Association, the left ventricular wall thickness and location of delayed-enhancement were verified, and the correlation of these two methods were analyzed in terms of the diagnosis of myocardial delayed enhancement (MDE).Results1360 myocardial segments for 80 patients were assessed. The left ventricular wall thickness determined by DSCT was significantly correlated with MR results (r=0.88,P<0.01). DSCT and MDE showed substantial agreement on per-patient (n=74,Kappa=0.751,P<0.05) and per-segment (n=1238, Kappa=0.746,P<0.01) levels. For dense myocardial delayed enhancement, CT findings were significantly correlated with those of CMR (r=0.89, P<0.01), but CT scan slightly underestimated the lesion scope of fibrosis. Bland-Altman analysis showed that CT and MRI were different in measuring the lesion volume of myocardial delayed enhancement (mean standard deviation was 2.71%).ConclusionThe cardiac CT examination provides comprehensive information in coronary artery and myocardial assessment, and MDE-DSCT is also effective in the diagnosis of myocardial fibrosis in HCM since it can be used in assessing myocardial fibrosis.