In comparison with the clinical PET scanner,PET scanner for small animals puts forward a higher demand in spacial resolution and sensitivity. This article describes the development of the PET scanner for small animals and compares the characteristics of several kinds of contemporary typical PET scanners for small animals in different aspects based on the development of detectors. Meanwhile,it also introduces the development of the detectors designed for measuring depth of interaction (DTC) to reduce parallax error.

Objective To observe the clinical, mammographic and sonographic features of pure invasive lobular breast carcinoma (ILC), and to explore the value of combined imaging assessment of ILC. Methods Sonographic appearances of 55 patients of ILC were retrospectively reviewed in correlation with mammographic, pathologic and clinical findings, and the causes of false negative were analyzed. Results The main features found in clinical examination were mass (96.15%) and thickening in the size of breast (3.85%). The main mammographic features were spiculated or ill-defined mass (65.38%) and architectural distortion (23.08%). The most common sonographic patterns were mass (98.00%) and distortion (2.00%). The accuracy for detecting ILC of clinical examination, mammography and ultrasonography was 94.55%, 83.87% and 98.04%, respectively, while combining the three modalities, the detection rate increased to 100%. Conclusion Sonography has higher accuracy than mammography in detecting ILC. Combining clinical examination, mammography and ultrasonography can increase the pre-operative diagnostic accuracy of ILC.

Objective To evaluate the usefulness of contrast enhanced ultrasound in the diagnosis of breast lesions. Methods Contrast enhanced ultrasound was performed after administration of SonoVue in 104 patients scheduled for surgical tumor removal. The enhancement morphology was classified as non, peripheral,homogeneous,regional,or heterogeneous enhancement based on distribution of enhancing areas. All breast lesions enhancement morphology were analyzed, and the diagnostic value of contrast enhanced ultrasound was calculated. Results The prevalence of non enhancement was significantly higher in benign lesions than in malignant ones(P = 0.013),and the prevalence of peripheral enhancement was significantly higher in malignant lesions than in benign ones (P = 6.02 × 10-7). Conclusions Contrast enhanced ultrasound is useful in diagnosis of breast lesions.

Objective To explore pre-hospital delay factor of coronary reperfusion therapy for ST-elevation acute myocardial infarction (STEAMI) patients presenting with non-chest pains. Methods A retrospective observation was conducted. The clinical data of STEAMI patients underwent emergency percutaneous coronary intervention (PCI) admitted to Luoyang Central Hospital Affiliated to Zhengzhou University from August 2013 to August 2015 were analyzed. The patients were divided into chest pain group and non-chest pain group according to the presence of chest pain or not. Clinical characteristics were compared between the two groups, and incidence of major adverse cardiac events (MACE), door-to-balloon time, door-to-electrocardiograms (ECG) time and ECG-to-balloon time were evaluated. Influencing factors of pre-hospital delay was analyzed by logistic multiple stepwise regression. Results A total of 259 patients with STEAMI were enrolled, including 154 patients with chest pain and 105 presented with non-chest pains. Compared with chest pain group, the patients in the non-chest pain group were older (years: 68.12±8.93 vs. 62.34±7.12, P < 0.05), less female (26.67% vs. 42.20%, P< 0.05), and had a higher past history of angina, stroke and heart failure (27.61% vs. 13.63%, 31.42% vs. 18.83%, 26.67% vs. 11.68%, respectively, all P < 0.05), and higher percentage of Killip ≥ Ⅲ patients (15.24% vs. 6.49%, P < 0.05), the lower ambulance use (26.67% vs. 44.81%, P < 0.01), longer hospitalization time (days: 12.50±2.89 vs. 9.50±2.67, P < 0.05), higher incidence of MACE (19.05% vs. 9.09%, P < 0.05), longer door-to-balloon time and door-to-ECG time (minutes: 159.01±51.21 vs. 115.31±36.74, 53.06±18.17 vs. 30.35±9.93, both P < 0.01). It was shown by logistic multivariate regression analysis that no-chest pain [odds ratio (OR) = 5.14, 95% confidence interval (95%CI) = 2.34-10.81, P < 0.001], age ≥ 65 years old (OR = 1.43, 95%CI = 0.93-2.99, P = 0.022), diabetes (OR = 1.57, 95%CI = 0.66-2.15, P = 0.015) and no-ambulance transport (OR = 1.55, 95%CI = 0.73-2.75, P < 0.001) were risks factors of coronary reperfusion delay ≥ 2 hours. Conclusions STEAMI patients presenting without chest pain showed higher incidences of MACE, longer time of ECG obtained and initial PCI time delay. Clinicians should try to reduce the delay time of the patients in order to improve patient survival rates.

ObjectiveTo investigate the correlation of ultrasonographic features of mesenteric fibromatosis and its pathological findings.MethodsTen mesenteric fibromatosis confirmed histopatho1ogica1ly in Peking Union Medical College Hospital were retrospectively reviewed.Results There were 7 females and 3 males. Their ages ranged 32~74 years (mean age 50.5±13.1 years). Of the 10 cases, 5 occurred in mesentery of the small bowels, 4 in the mesocolons, and 1 in junction portion of duodenum and jejunum. On ultrasound image, the diameters of the masses were 4.3~22.0 cm (mean 8.8±5.2 cm). 6 were regular and 4 were irregular. 9 of 10 cases were well-defined and 1 was poor defined. 6 has capsule echoic. All the 10 cases were hypoechoic. 9 presented as solid mass and 1 was solid-cystic leision. On gross pathology,they were solid, firm, grey and yellowish. Histopathology, there were boundles of fibroblasts in collagenous stroma with scarce degeneration. The cystic changes noted on sonograms corresponded histopathologically to areas of myxoid and cystic degeneration.ConclusionsMesenteric fibromatosis is a rare disease with characteristic ultrasonographic features, which were well correlated with their pathology findings. They mostly presents as well-circumscribed masses with hypoecho, regular shape and little vascularity. Ultrasound was important in the diagnosis of this disease.

Objective To evaluate the contrast enhanced perfusion pattern of PTC micro-vascular imaging (MVI) quantitatively.Investigate the correlation between PTC MVI features and CD34 micro-vascular density (MVD).Methods Thirty-nine pathological and clinical confirmed sporadic PTCs were evaluated with real-time gray-scale contrast-ernhanced micro-vascular imaging under a low mechanical index.The micro-bubble agent was SoneVue.Of the 39 PTCs,33 were classical PTCs,6 were PTC with follicular variant (FVPTC).The △ ROI,which is the subtraction of peak echo intensity between the lesion region of interest (ROI) and normal thyroid parenchyma ROI,was used to evaluate the perfusion characteristics of PTC MVI quantitatively.The paraffined specimens were selected for immunohistochemical (IHC) staining for CD3,and the correlation between △ ROI and the CD34 were evaluated.Results △ ROI was strongly correlated with the CD34 expression (P=0.000),significant differences were detected in the distribution pattern of △ ROI value among different CD34 expression levels,no overlapping of the mean △ ROI values and the 95％ confidence intervals was found among the 3 CD34 expression levels.The PTC MVI perfusion was classified into 3 patterns,low perfusion,focal perfiusion and high perfusion,on the basis of combining△ ROI values with the peak ehco pattem in time-intensity curve.Conclusions The △ ROI is strongly correlated with the CD34 expression in papillary thyroid cancer.It can be used for the quantitative evaluation ofPTC MVI pattem and intensity as an objective indicator.

Objective To measure total hemoglobin concentration (THC) of breast lesion using US-guided diffused optical tomography(DOT) and to investigate the THC optimal threshold value in different size breast lesions.Methods DOT was performed on 500 breast lesions and surgical pathology was as the gold standard.The optimal diagnostic threshold and the efficacy were figured out.Results There were 265 benign and 235 malignant lesions.In malignant lesions,THC of ≥2 cm lesion group was higher than that of ＜2 cm lesion group(P =0.000).In benign lesions,there was no statistical difference between ≥2 cm group and ＜2 cm group (P =0.13).As for ＜2 cm breast lesions,when a THC threshold value of 146.9 μmol/L and 102.2 μmol/L were used,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy were 74.2％,70.0％,71.7％,62.9％,79.9％ and 86.7％,44.4％,61.6％,51.6％,83％,respectively.As for ≥2 cm breast lesions,when a THC threshold value of 210.4 μmol/L were used,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy were 74.0％,86.7％,79.1％,89.2％,69.2％.Conclusions THC of breast cancer increased with the increasing size of lesions.The different diagnostic threshold value should be used according to different size lesions so as to enhance sensitivity,specificity and accuracy.

Objective To investigate the ultrasonographic manifestation of renal oncocytoma. Methods The sonographic appearances of 12 patients with pathologically confirmed RO were retrospectively reviewed, and the size, margin, configuration, echogenicity and blood flow distribution of the lesions were analyzed. Results All of the 12 RO were detected and located correctly, among which 3 cases were misdiagnosed as renal cell carcinoma and 9 cases were not qualitatively diagnosed with ultrasound. The lesions manifested as central stellate scar in 8.33%, homogeneous enchogenicity in 66.67%, well-defined in 75.00%, regular-shape in 91.67% and isoechoic in 58.33%. Among these lesions, 6 (50.00%) were hypervascular with spoke-wheel distribution, 5 (41.67%) were hypovascular, and 1 (8.33%) was avascular, while peripheral blood flow were seen in 7 lesions (66.67%). Conclusion The diagnostic ability of ultrasound for RO is limited, but a homogeneous, well-defined solid lesion with spoke-wheel distribution of blood flow, especially with a stellate scar may suggest RO.

Objective Tumor size discrepancy in measurement between real-time ultrasonic elastography and conventional uItrasound(US) was found in some breast lesions.The study was designed to investigate the value of the feature in the diagnosis of breast cancer,and its relationship with the margin features on gray-scale US.Methods Both US and real-time elastogram using a Hitachi EUB-8500 US system were performed in 308 consecutive Datients.The margin features on US and the size measured on both methods were documented.A lesion was defined as a significant size discrepancy when a larger size measured at elastogram.Sensitivity,specificity,and overall accuracy of feature to diagnosis malignancy were determined by surgical pathology as gold standard.Results There were total 166 benign,163 malignant and 3 borderline lesions.of 99 lesions with larger measurement on elastography,there were 91 malignant lesions and 8 benign lesions.By the feature of size discrepancY,the sensitivity,specificity and accuracy was achieved 55.8%,96.9%,75.7%,respectively.The size measured on elastogram was statistically larger than that on gray scale US(t=-11.0,P＜0.05).The ratio of indistinct,angular and spiculated margin characteristics were significantly higher in breast cancers with larger size measurement than those with unchanged or decreased size measurement(P＜0.05).Conclusions The increased size-measurement at elastography is helpful to diagnosis breast cancers.And it is more likely to be present in breast cancers with indistinct,angular or spiculated margin.

Objective To determine the diagnostic value and clinical significance of sonographically detected fetal dysplastic kidney with normal amniotic fluid volume. Methods At the 2nd or 3rd trimester of gestation,the fetuses with unilateral or bilateral renal anomalies (ahnormal size,echo,shape or cyst of the kidney) and normal amniotic fluid volume received systemic ultrasound examination,autopsy or follow-up until after birth. The fetus with only dilated renal pelvis was not included. Results Eleven fetuses of dysplastic renal anomalies with normal amniotic fluid volume were identified by prenatal ultrasound. Among the five fetuses affected by unilateral multicystic kidney dysplasia (MCKD),the renal anomaly was isolated in four fetuses,and the other one was complicated with absence of the ipsilateral hand. One of the two fetuses of unilateral renal agenesis had no other associated anomaly and the other one was complicated with hydrocephalus,spina bifida,ipsilateral absent radius and single umbilical artery,correspongding to the VACTERL syndrome. Two fetuses of pelvic kidney and horseshoe kidney respectively was proved by postnatal ultrasound. One fetus was diagnosed as autosomal dominant polycystic kidney disease(ADPKD)on the basis of multiple renal cysts and a positive family history,the fetus also had cardiac rhabdomyoma. One fetus of bilateral normal sized hyperechoic kidneys was proved to be renal dysplasia by autopsy. Conclusions Unilateral MCKD is the most common type of fetal renal dysplasia which can be detected by prenatal ultrasound with normal amniotic fluid volume. Based on the sonographic characteristics and the family history,most of the dysplastic renal anomalies can be diagnosed prenatally and the prognosis can be predicted.