With the development of radiologic intervention, the treatments of aortic dissection are getting more and more diversified. In recent years, Debakey Ⅲ and DebakeyⅠaortic dissection has been usually treated with endovascular graft exclusion, or combined surgical and endovascular treatment. It is therefore more important to evaluate the aorta and its complications after interventional treatments. Because multidetector-row computed tomography (MDCT) has advantages, such as short examination time, high spatial resolution, and simple operation, this modality has become a first choice of non-invasive methods for the follow-up of aortic diseases after the intervention. Now the MDCT presentations and their anatomic-pathologic features of aortic dissection after endovascular graft exclusion or combined surgical and endovascular treatment are reviewed in this article.
Objective To describe the role of breast palpation imaging (PI) in breast cancer screening. Method We searched the latest research and previous literatures of PI in the diagnosis of breast cancers, and made an review after reading the articles. Results PI had better diagnostic efficiency than clinical breast examination (CBE) in breast cancer screening. PI combined with mammography (MG) and/or breast ultrasound (BUS) could further improve the diagnostic efficiency. Conclusion PI has important value in breast cancer screening, and is an important supplement to existing breast cancer screening methods.
ObjectiveTo analyze the influencing factors for image quality of 18F-deoxyglucose (FDG) positron emission tomography (PET)/CT systemic tumor imaging and explore the method of control in order to improve the PET/CT image quality. MethodsRetrospective analysis of image data from March to June 2011 collected from 1 000 18F-FDG whole body tumor imaging patients was carried out. We separated standard films from non-standard films according to PET/CT image quality criteria. Related factors for non-standard films were analyzed to explore the entire process quality control. ResultsThere were 158 cases of standard films (15.80%), and 842 of non-standard films (84.20%). Artifact was a major factor for non-standard films (93.00%, 783/842) followed by patients’ injection information recording error (2.49%, 21/842), the instrument factor (1.90%, 16/842), incomplete scanning (0.95%, 8/842), muscle and soft tissue uptake (0.83%, 7/842), radionuclide contamination (0.59%, 5/842), and drug injection (0.24%, 2/842). The waste film rate was 5.80% (58/1 000), and the redoing rate was 2.20% (22/1 000). ConclusionComplex and diverse factors affect PET/CT image quality throughout the entire process, but most of them can be controlled if doctors, nurses and technicians coordinate and cooperate with each other. The rigorous routine quality control of equipment and maintenance, patients’ full preparation, appropriate position and scan field, proper parameter settings, and post-processing technology are important factors affecting the image quality.
目的:探讨急性胰腺炎的胸腹部X线平片显示特征及诊断。方法:回顾分析19例急性重症胰腺炎的胸腹部X线平片资料,总结其影像特征。结果:急性胰腺炎胸腹部X线平片显示反射性肠郁积15例,十二指肠曲部见弧形压迹1例, 剑突下胰腺区高密度影1例,麻痹性肠梗阻伴胸腔积液2例。结论:胸腹部X线平片经济,快捷,在急性胰腺炎早期诊断中有一定价值。
Objective To investigate the CT imaging features of hepatic angiomyolipoma and its clinical characteristics. Methods The clinical, radiological, and pathological data of 3 hepatic angiomyolipoma (HAML) patients were retrospectively collected, and the imaging and diagnostic features were analyzed.Results All 3 cases were females, 2 complained of abdominal pain and one was absent of symptom. Both the laboratory examinations were normal in 2 cases, and hepatitis B virus markers were positive in one case. For CT features, the mass located in the superior anterior segment of the right hepatic lobe, in the posterior inferior segment of the right hepatic lobe, and in the left medial lobe, respectively. There were components of fat and soft tissue attenuation in these masses, and in which the CT value of the fat component was from -80 HU to -20 HU (mean -50 HU). There were enhancement in different degree and enhanced vascular imaging could be seen within the lesions. During surgery, all 3 masses were outgrowed from the hepatic lobes. Immunostainning showed HMB45 (+), αSMA (+), S100 (+)，which were bly suggestive of HAML.Conclusion HAML is a rare benign tumor with characteristic CT appearance, and its definite diagnosis relies on the immunohistochemical staining of HMB-45.
目的 探讨镰状韧带引起假性病灶的影像学表现，以提高对其的认识，减少误诊。 方法 对2010年1月－2012年1月收入的817例患者进行上腹部64排CT平扫加增强扫描，筛选出肝镰状韧带附近假病灶，详细记录其部位、大小、形状以及扫描各期图像的密度变化情况。 结果 有72例存在镰状韧带假病灶，绝大多数位于肝左叶内侧段（69例），并呈单发病灶（70例）。假病灶最大直径约5.1～22.0 mm，平均约13.1 mm，假病灶分别呈三角形43例、类圆形19例、结节状10例。CT扫描：平扫显示10例，动脉期显示63例，门脉期几乎全部显示清晰。 结论 镰状韧带形成假病灶比较少见，其发生部位特殊，在门脉期易于显示，可与肝内真性病灶鉴别，以免误诊。
There are some problems in positron emission tomography/ computed tomography (PET/CT) lung images, such as little information of feature pixels in lesion regions, complex and diverse shapes, and blurred boundaries between lesions and surrounding tissues, which lead to inadequate extraction of tumor lesion features by the model. To solve the above problems, this paper proposes a dense interactive feature fusion Mask RCNN (DIF-Mask RCNN) model. Firstly, a feature extraction network with cross-scale backbone and auxiliary structures was designed to extract the features of lesions at different scales. Then, a dense interactive feature enhancement network was designed to enhance the lesion detail information in the deep feature map by interactively fusing the shallowest lesion features with neighboring features and current features in the form of dense connections. Finally, a dense interactive feature fusion feature pyramid network (FPN) network was constructed, and the shallow information was added to the deep features one by one in the bottom-up path with dense connections to further enhance the model’s perception of weak features in the lesion region. The ablation and comparison experiments were conducted on the clinical PET/CT lung image dataset. The results showed that the APdet, APseg, APdet_s and APseg_s indexes of the proposed model were 67.16%, 68.12%, 34.97% and 37.68%, respectively. Compared with Mask RCNN (ResNet50), APdet and APseg indexes increased by 7.11% and 5.14%, respectively. DIF-Mask RCNN model can effectively detect and segment tumor lesions. It provides important reference value and evaluation basis for computer-aided diagnosis of lung cancer.
ObjectiveTo explore the diagnostic value of CT-guided percutaneous needle aspiration biopsy (PTNB) for ground-glass opacity (GGO) pulmonary lesions. MethodsA retrospective design was used to collect clinical data of patients with GGO lesions admitted in the Affiliated Hospital of North Sichuan Medical College between Jan. 2009 to Jan 2015. Patients were divided into groups according the lesion size (≤10 mm, 10-20 mm,≥20 mm), length of needle path (≤5 cm, 5-9 cm,≥9 cm) and percentage of GGO component (50%-90%, >90%), respectively. The total and subgroups of sensitivity, specificity, and diagnostic accuracy of CT guided PTNB for diagnosing GGO were calculated and the differences among subgroups were compared using Fisher's exact test. Statistical analysis was conducted by using SPSS 17.0 software. ResultsA total of 60 patients involving 48 malignant and 12 benign lesions were included. The total sensitivity, specificity, and accuracy of CT guided PTNB for diagnosing GGO were 87.5%, 100% and 90%, respectively. There were no significant differences among the subgroups based on the lesion size, length of needle path, and percentage of GGO component (all P values >0.05). ConclusionCT-guided PTNB can be used as one of the diagnostic modalities for lung GGO lesions with a moderate diagnostic value.
Objective To probe CT grading criteria of vascular invasion in pancreatic cancer. Methods Retrieved articles in CNKI and PubMed about value of CT in preoperative assessment of vascular invasion in pancreatic cancer last ten years. Results Multislice helical CT is considered the best imaging method to assess the invaded peripancreatic vessels in pancreatic cancer. There are different CT criteria of vascular invasion in pancreatic cancer based on extension of hypodense tumor and its relation to blood vessels, on the degree of circumferential contiguity of tumor to vessel, on the degree of lumen stenosis, and on the degree of contiguity between tumor and vessels combined vascular caliber. Conclusion CT grading criteria are not uniform, each one has defects.