PurposeTo explore the value of gemstone spectral imaging (GSI) in diagnosis of thyroid nodule hemorrhage.Materials and Methods Seventeen patients with surgery and pathology confirmed thyroid nodule hemorrhage underwent thyroid spectrum CT scan. The CT value, iodine concentration value, water concentration value and the effective atomic ordinal value as well as spectral curve slope of hemorrhagic nodules and surrounding normal thyroid tissue were measured respectively.Results Hemorrhagic thyroid nodules showed equal or high CT value, low concentration of iodine, high concentration of water, low spectral curve slope, and low effective atomic ordinal value on spectral CT imaging. There were statistically significant differences in concentration of iodine value, concentration of water value, and spectral curve slope between hemorrhagic nodules and surrounding normal thyroid tissue (Z=-5.438,-4.679 and-5.317,P<0.01), and there were statistically significant differences in CT value and effective atomic ordinal value (Z=-2.097 and-2.230,P<0.05).Conclusion Energy spectrum CT scan is important in detection and accurate diagnosis of thyroid nodule hemorrhage.

PurposeTo evaluate the value of dual-source CT angiography (DSCTA) in the diagnosis of carotid atherosclerosis, and to explore the relationship between carotid atherosclerosis and diabetes mellitus (DM).Materials and Methods 145 patients with ischemic stroke were divided into DM group (n=80) and non-DM group (n=65). All patients underwent DSCTA. The location and characteristic of carotid atherosclerosis were analyzed using curve planE reconstruction (CPR), maximum intensity projection (MIP), multi-plane reformation (MPR) and volume rendering (VR). The differences between two groups were analyzed.Results Compared with non-DM group, the body mass index and high blood cholesterol were higher in DM group (t=6.197,P<0.05;χ2=8.372,P<0.01). The incidence of carotid atherosclerosis and vulnerable plaques were also higher in DM group than non-DM group (χ2=11.617 and 9.388,P<0.01). There was no significant difference between DM group and non-DM group in the location of carotid atherosclerosis (χ2=0.160, 0.509, 0.419 and 0.016,P>0.05). Carotid atherosclerosis was more common in carotid bifurcation and carotid artery siphon.Conclusion DSCTA can demonstrate the location and characteristics of carotid atherosclerosis in ischemic stroke patients with diabetes mellitus. Diabetes is a risk factor for the formation of carotid atherosclerosis, especially vulnerable plaques.

PurposeTo explore the left ventricle flow propagation process in patients with chronic heart failure (CHF) using velocity flow mapping. Materials and Methods Patients with CHF (n=25) were selected as CHF group. Healthy subjects (n=28) were chosen as the control group. Flow reversal interval (FRI), flow reversal rate (FRR), corrected flow reversal rate (CFRI) and flow rate in peak ejection (FRPE) were measured. Parameters related to the vortex in CHF group were compared with that in the control group. Results Compared with the control group, FRI was longer [(71±13) msvs. (113±30) ms, P<0.05], FRR and FRPE were lower [(46.85±21.35) cm2/svs. (27.90±16.77) cm2/s;(74.54±9.10) cm2/svs. (41.12±17.25) cm2/s,P<0.05] in CHF group. FRI and CFRI were positively correlated with the Tei index (r=0.812 and 0.849,P<0.01). FRI was negatively correlated with LVEF, FS, SV, CO, CI (r=-0.646--0.515,P<0.05 orP<0.01). CFRI was negatively correlated with LVEF, FS, SV, CO and CI (r=-0.685--0.456,P<0.05 orP<0.01); FRR was negatively correlated with Tei index (r=-0.604,P<0.05), and was positively correlated with LVEF, FS, SV, CO and CI (r=0.503-0.812,P<0.05 orP<0.01);FRPE was negatively correlated with Tei index (r=-0.734,P<0.01), and were positively correlated with LVEF, FS, SV, CO and CI (r=0.557-0.776,P<0.05 orP<0.01).Conclusion Velocity flow mapping can demonstratecardiac hydromechanics in patients with chronic heart failure. The heart blood flow direction reversal efficiency may be a new method for diagnosis and treatment evaluation.

PurposeTo investigate whole-body magnetic resonance imaging in diagnosis of idiopathic inflammatory myopathy (IIM), and to guide clinical treatment.Materials and Methods Twenty-six patients clinically diagnosed IIM including 19 dermatomyositis and 7 polymyositis were analyzed retrospectively. Whole-body MRI was performed in all patients including whole-body coronal scan and axial scan of both sides of thigh. Short tau inversion recovery (STIR) sequences were used in the coronal scan and T1WI and fat-suppressed T2WI were performed in the axial scan. Ten healthy volunteers were recruited as control group. MRI findings were compared between the two groups.Results Whole body MRI showed that muscles were homogeneously low signal intensity in the control group. Imaging findings of the patients with IIM included muscle inflammation, fascitis, subcutaneous tissue edema, muscle atrophy and fatty infiltration. The most common distribution site of muscle inflammation of dermatomyositis patients was thigh (n=18), followed by gluteus (n=14), great psoas muscle (n=13), shoulder muscles (n=11), leg muscle (n=11), erector spinae (n=10) and neck muscles (n=9). Findings out of muscles included cavities in the both lungs, infarction in femurs and tibias, avascular necrosis of femoral head, adrenal mass and thyroid nodules. The most common distribution site of muscle inflammation of polymyositis was thigh (n=5), followed by gluteus (n=3), great psoas muscle (n=3), shoulder muscles (n=2), leg muscles (n=2), erector spinae (n=1) and neck muscles (n=1). Findings out of muscles included 1 case of infarction in femurs and tibias.Conclusion Whole-body MRI can not only comprehensively evaluate the activity of IIM but also detect complications such as bone infarction. It's a powerful tool for diagnosis, guiding treatment and monitoring of IIM.

PurposeTo evaluate multislice spiral CT (MSCT) in diagnosing abdominal anaphylactoid purpura (AAP), and to explore its role in treatment follow-up.Materials and Methods Clinical and MSCT data of 13 patients with confirmed AAP were retrospectively analyzed. All patients underwent abdominal CT scan and thin layer reconstruction. Upper endoscopy was performed in 8 patients prior to treatment. MSCT was performed in 10 patients and endoscopy in 4 patients posttreatment, then clinical and CT features were compared to pretreatment findings.Results In pretreatment CT scan, single segment bowel involvement was found in 2 cases, multisegmental bowel involvement in 10 cases, and no positive finding in 1 patient. The duodenum and jejunum were involved in 8 patients and stomach in 5 patients. The diseased bowel wall showed swelling and thickening with decreased attenuation and homogeneous luminal narrowing with equivocal lining and double loop sign. Infiltration was found in 10 patients, small ascites in 3 patients. Patients were misdiagnosed as acute pancreatitis in 2 cases, acute cholecystitis, small bowel obstruction and peritonitis in 1 case respectively. Of 13 patients, five patients were cured, and the other 8 patients were improved. The clinical symptoms including rash, abdominal pain, occult blood, leukocytosis, vomiting, melena, urine occult blood were improved (χ2=5.59-18.33,P<0.05 orP<0.01). Post treatment CT showed significant improvement of bowel edema and infiltration (P<0.01). There was no statistically significant difference in change of ascites (P>0.05).Conclusion MSCT findings of AAP are nonspecific. CT diagnosis is difficult before skin rash. Combining CT characteristics of multisegmental bowel edema and clinical manifestations is helpful. CT examination can effectively follow up treatment response.

PurposeTo evaluate 64-slice spiral CT in grading of colorectal adenoma and in the diagnosis of adenocarcinoma.Materials and Methods Sixty-eight cases of pathology confirmed colorectal adenoma were retrospectively reviewed to analyze CT performance including the location, size, shape and their relationship with adjacent structures and degree of enhancement in arterial, venous and delayed phase. The difference of CT attenuation value before and after enhancement (△CT value) in arterial, venous and delay phase of different pathological types and different levels of adenomas were compared.Results Among 68 lesions, 16 were villous adenomas, 42 were tubulovillous adenomas and 10 were tubular adenomas. Villous adenomas and tubulovillous adenomas were characterized by wide base, villous-like with gyral or frond pattern enhancement in arterial phase. There was a layer of low density mucus covering the surface. Tubular adenomas were featured as narrow base, nodular in shape with homogeneous enhancement.△CT values in each phase between villous adenomas and tubular adenomas showed statistically significant difference (arterial phaset=2.56,P<0.05; venous phaset=3.22,P<0.05; delayed phaset=2.48,P<0.05), however no significant difference was shown between villous and tubule villous adenomas or between tubulovillous and tubular adenomas. Adenocarcinomas showed creeping-type growth along the intestinal wall with a cluster of vessels adjacent to the tumor or enlarged lymph nodes.△CT values in each phase between non-dysplasia group and carcinoma group showed statistically significant difference (arterial phaset=2.49,P<0.05; venous phase t=2.69,P<0.05; delayed phaset=2.75,P<0.05), however no significant difference was shown between non-dysplasia group and dysplasia group or between dysplasia group and carcinoma group. Using 50 HU of△CT value in artery phase as standard, the sensitivity and specificity for diagnosis of adenocarcinomas were 76.92% and 70.91%, respectively.Conclusion CT findings of different pathological types of colorectal adenomas and adenocarcinomas are characteristic and useful in preoperative diagnosis and treatment planning.

PurposeTo investigate the role of diffusion weighted imaging (DWI) in the detection of focal liver lesions (FLL).Materials and Methods T2WI, dynamic contrast enhancement (DCE) and DWI (b=100 s/mm2 and 600 s/mm2 respectively) were performed in 205 patients with 310 FLLs. All images were read by two reviewers to determine the detection of FLLs and score the confidence. The consistency of the results given by the two reviewers was evaluated. The confidence scores between different sequences and the detection rate of different sequences were also compared.Results The consistency of the two reviewers was excellent or good in T2WI, high b value DWI, low b value DWI, and DCE (Kappa=0.71, 0.85, 0.82 and 0.64,P<0.05). As to the confidence score of lesion detection, high b value DWI and low b value DWI were both significantly higher than T2WI (P<0.01), but both were lower than DCE (P<0.01). DWI yielded higher score and detection rate for detecting FLLs than T2WI (86.5%vs. 70.3%,P<0.01), but lower than DCE (91.6%,P<0.05). For small malignant lesions (≤2 cm in diameter), DWI showed similar detection rate with DCE (P>0.05), but higher than T2WI (P<0.01). The combination of DWI and DCE detected more small malignant lesions than DWI or DCE alone (P<0.01).Conclusion DWI can detect more FLLs than T2WI, and can help DCE detect small malignant FLLs. Therefore DWI is suggested to be included in the routine protocol of liver MRI examination.

PurposeTo evaluate the value of combined employment of thyroid imaging-reporting and data system (TI-RADS) and ultrasound elastography (UE) in the differentiation of benign and malignant thyroid nodules.Materials and Methods The clinical data of 174 patients with 232 thyroid nodules confirmed surgically or pathologically with puncture biopsy were retrospectively analyzed. All nodules were examined by ultrasound and UE. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of TI-RADS, UE and the combination of the two methods were calculated respectively, and the receiver operating characteristic curve (ROC) was drawn to evaluate the value of each of the three methods in differentiating benign and malignant thyroid nodules by comparison of area under curve (AUC).Results The diagnostic sensitivity, specificity and accuracy of UE (number of benign nodules: 155, number of malignant nodules: 77) were 88.9%, 91.8% and 90.9%, respectively; those of TI-RADS (number of benign nodules: 153, number of malignant nodules: 79) were 76.4%, 85.0% and 82.3%, respectively. The values measured by UE were significantly higher than those by TI-RADS (χ2=3.920 and 7.446,P<0.05). The sensitivity, specificity and accuracy measured by the combined use of the two methods (number of benign nodules: 155, number of malignant nodules: 77) were 93.0%, 93.7% and 93.5%, respectively, which were higher than either of the methods, and the difference was statistically significant (χ2=7.725, 6.450 and 13.728,P<0.05). The areas under the curve (AUC) were 0.833 and 0.812 respectively for UE and TI-RADS; the AUC for the combination of the two methods was 0.914, which had significantly higher diagnosis accuracy than that by any single method, and the difference was statistically significant (Z=1.95 and 2.55,P<0.05). Conclusion Compared with gray scale ultrasound, the combination of TI-RADS and UE has higher diagnostic sensitivity and accuracy for excluding malignancy in diagnose of thyroid nodules.

PurposeTo investigate clinical significance of echocardiography combined with Flash CT in diagnosis of partial anomalous pulmonary venous connection (PAPVC). Materials and Methods Twenty-eight cases of PAPVC were recruited in the study. All the subjects underwent both preoperative echocardiography and coarse pitch Flash CT scanning. Imaging findings were compared with the results of surgery, including the type of PAPVC, size of atrial septal defect (ASD), and other combined malformations. Results Among 28 patients, 16 cases and 5 suspicious cases (4 cases of PAPVC and 1 case of pulmonary vein embolism) were diagnosed by echocardiography. Six cases were missed, and 1 case was misdiagnosed. CT misdiagnosed 1 case. The accurate diagnosis rate of echocardiography (71.4%, 20/28) was lower than that of Flash CT (96.4%, 27/28) (P<0.05). There were 44 combined malformations in 28 cases, 43 lesions were diagnosed by echocardiography, and 34 lesions were diagnosed by Flash CT. The accurate diagnosis rate of echocardiography (97.7%, 43/44) was higher than that of Flash CT (77.3%, 34/44) (P<0.05). The average DLP was (15.5±3.2) mGy·cm and average effective dose (ED) was (0.354±0.058) mSv.Conclusion Flash CT has a higher diagnosis accuracy of PAPVC but a lower diagnostic accuracy of combined malformations when compared with echocardiography. Moreover, echocardiography can make comprehensive evaluation in valve disease, pulmonary artery pressure and cardiac function. Flash CT combined with echocardiography may improve preoperative diagnosis.

PurposeTo evaluate left ventricular function in patients with non-obstructive hypertrophic cardiomyopathy (HCM) by using three-dimensional speckle tracking imaging (3D-STI).Materials and Methods Twenty-eight patients with non-obstructive hypertrophic cardiomyopathy (HCM group) and 30 healthy volunteers (control group) underwent both conventional two-dimensional echocardiography and 3D-STI. Indexes of conventional echocardiography including interventricular septal thickness (IVST), left ventricular posterior wall at end-diastolic thickness (LVPWT), left ventricular diameter, left ventricular volume, end-systolic left ventricular volume, peak velocity of early diastolic mitral valve, peak diastolic of late diastolic mitral valve, outflow tract frequency spectrum of the aortic valve and left ventricular were compared between the two groups to get the pressure difference and velocity time integral of the left ventricular outflow tract. Early and late diastolic peak velocity of mitral annular were calculated and E/A, Ea/Aa, E/Ea were also obtained. 3D-STI indicators including three-dimensional left ventricular ejection fraction (3D-LVEF), sphericity index (SPI) and global area of strain (GAS), global longitudinal train (GLS), global circumferential strain (GCS), global radial strain (GRS) were also compared.Results In HCM group, IVST, LVPWT and E/Ea increased (P<0.01), Ea/Aa and E/A decreased significantly (P<0.01), LVOT-PG and LVOT-VTI increased significantly (P<0.05 orP<0.01). GCS, GAS, GLS and GRS were significant lower in HCM group than those in control group (P<0.01). Local strain values at the level of papillary muscle and apex were decreased, which were significantly decreased at ventricular septum, anterior wall and inferior wall.Conclusion HCM patients have various degree of decreased myocardial contractility. The real time 3D-STI offers a novel way to assess the left ventricular function of patients with HCM.