Search

Early radiological diagnostic value of closed chest trauma in rabbits

Objective To explore the early diagnostic value of single photon emission computed tomography(SPECT), thoracic computed tomography(CT),and chest X-ray for closed chest trauma. Methods To establish the animal model of unilateral chest impact trauma,to adopt SPECT, thoracic CT, and chest X-ray for early diagnosis of closed chest trauma,and to compare these findings with postmortem examination. Results Thirty minutes after blunt chest trauma, the region of interesting (ROI) between traumatized lung and the heart (ROI2/ROI1) immediately increased to the peak six hours after trauma; on the contralateral lung, the ratio (ROI3/ROI1) increased slowly and reached the peak after six hours, these ratio was still smaller than that of the traumatized lung. These differences were significant (Plt;0.01). Conclusions Chest X-ray is still the most fundamental diagnostic method of chest trauma,but it was thought that the patients of severe chest trauma and multiple injuries should be examined early by thoracic CT. Radionuclide imaging have more diagnostic value than chest X-ray on pulmonary contusion. The diagnostic sensibility to pulmonary contusion of thoracic CT is superior to conventional radiograph,but thoracic CT is inferior to SPECT on exploring exudation and edema of pulmonary contusion. Thoracic CT is superior to conventional radiograph on diagnosis of chest trauma,therefore patients of severe chest trauma and multiple injuries should be adopted to thoracic CT examination at emergency room in order to be diagnosed as soon as possible.

CT 扫描诊断下胫腓联合损伤的应用评价

目的 评估CT 扫描诊断下胫腓联合损伤的应用价值，为临床诊断下胫腓联合损伤提供有效的诊断方法。 方法 2007 年3 月－ 2009 年2 月，收治68 例闭合性踝部骨折患者。男45 例，女23 例；年龄18 ～ 63 岁，平均36.7 岁。Lange-Hanson 分型：旋前外旋型23 例，旋前外展型19 例，旋后外旋型12 例，旋后内收型11 例，垂直压缩型3 例。Denis-weber 分型：A 型7 例，B 型28 例，C 型33 例。受伤至手术时间6 ～ 144 h，平均94 h。术前常规摄X 线片及行CT扫描诊断下胫腓联合损伤情况。采取切开复位内固定治疗，术中探查下胫腓联合损伤情况并作为“金标准”，与术前X 线片和CT 扫描结果进行统计学比较分析。 结果 术中手术探查46 例存在下胫腓联合损伤，22 例未见损伤。术前X 线片诊断下胫腓联合损伤真阳性25 例，真阴性16 例，假阳性6 例，假阴性21 例，灵敏度54.34% ± 14.38%，特异度72.72% ±18.60%，准确度60.29% ± 11.62%，阳性预测值80.64% ± 13.89%，阴性预测值43.24% ± 20.34%；术前CT 扫描诊断真阳性43 例，真阴性21 例，假阳性1 例，假阴性3 例，灵敏度93.47%±7.11%，特异度95.45% ± 8.66%，准确度94.11% ± 5.58%，阳性预测值97.72% ± 4.39%，阴性预测值87.50% ± 13.21%；CT 扫描各指标均明显高于X 线片（P lt; 0.05）。Kappa 指数显示CT 扫描与手术探查结果存在一致性，可靠性高；X 线片可靠性低。 结论 单纯根据X 线片诊断下胫腓联合损伤可靠性低，CT 扫描诊断下胫腓联合损伤可靠性高、真实性好，能够提供重要的临床参考价值。

原发性输尿管肿瘤的影像学诊断

【摘要】 目的 探讨影像学检查对原发性输尿管肿瘤的检查方法及征像。 方法 回顾性分析2001年1月-2010年12月经手术病理证实的23例原发输尿管肿瘤影像学表现及征像。 结果 根据影像学表现，输尿管原发肿瘤多发生于中老年男性输尿管下段，静脉肾盂造影21例检查中，仅3例输尿管腔内充盈缺损。逆行肾输尿管检查18例中，10例插管受阻，显示肿瘤远端呈杯口状改变，5例导管可通过，显示充盈缺损。CT扫描17例中，3例发现输尿管肿块，2例误诊为膀胱肿瘤。B超检查22例中，3例直接探及输尿管肿瘤。 结论 逆行肾输尿管造影检查对诊断输尿管肿瘤意义重大，诊断符合率为83.3%，CT、B超及静脉肾盂造影远不及逆行肾输尿管造影。膀胱镜检查对某些输尿管下段肿瘤有诊断意义。

Preoperative Image Evaluation for Bile Duct Carcinoma

Imaging Features of Autoimmune Pancreatitis in 13 Cases

目的总结自身免疫性胰腺炎（AIP）的影像学特点。 方法回顾性分析13例经手术病理学检查或糖皮质激素治疗证实的AIP患者的临床资料。 结果13例均行CT检查，7例同时行MRI检查、DWI扫描及磁共振胰胆管造影（MRCP）检查，2例同时行超声检查。8例表现为胰腺弥漫性肿大，4例表现为胰腺局限性肿大，1例表现为胰腺混合型肿大。CT动态增强扫描结果提示，胰腺病变呈“雪花状”渐进性强化，T1WI信号减低，T2WI信号略高，DWI信号增高；MRCP检查可见胆总管胰内段呈“鸟嘴样”狭窄；超声检查显示胰腺病变部位肿大，回声减低。 结论AIP具有典型的影像学特征，影像学检查是发现和诊断AIP的重要手段。

Application of MRI imaging features and tumor distance measurement in preoperative evaluation of rectal cancer

Objective To investigate the application of magnetic resonance imaging (MRI) in preoperative assessment of rectal cancer. Methods Combined with the literatures, the MRI features and measurements of rectal tumor staging, extramural vascular invasion, circumferential margin involvement, and the distance between distal margin of the tumor from the anorectal ring and the anal margin were described. Results On T2-weighted images (T2WI), T1 staging-tumors were those in which the normal submucosa was replaced by the iso-intensity of tumor tissue without invasion of muscularis propria; T2 staging-tumors were those with extension into the muscularis propria, but not invaded the high-intensity of mesorectal fat; T3 staging-tumors manifested as the rectal tumor penetrated into the muscularis propria and invaded the high-intensity of mesorectal fat; T4 staging-tumors manifested as the tumor invaded adjacent structures or organs. The metastatic lymph nodes were showed with irregular boundaries and mixed signals on T2WI. The tumor signals could be found in the extramural vascular on T1-weighted images (T1WI), accompanied by irregular distortion and expansion of the blood vessels. On T2WI, metastatic lymph nodes, extramural vascular invasion, and the distance between the residual tumor and the low-signal of mesorectal fascia was within 1 mm, indicated the positive circumferential margin. On T2WI, the distal margin of the tumor was located at the junction of hyperintense submucosa and iso-signal of tumor, the tip of the iso-signal puborectal muscle was the apex of the anorectal ring, and the lowest point of the iso-signal external sphincter was the anal margin. Conclusion MRI can provide reliable imaging information for preoperative staging, height measurement, and prognosis of rectal cancer, and it is helpful for early diagnosis and treatment of rectal cancer.

A survey on the application of convolutional neural networks in the diagnosis of occupational pneumoconiosis

Pneumoconiosis ranks first among the newly-emerged occupational diseases reported annually in China, and imaging diagnosis is still one of the main clinical diagnostic methods. However, manual reading of films requires high level of doctors, and it is difficult to discriminate the staged diagnosis of pneumoconiosis imaging, and due to the influence of uneven distribution of medical resources and other factors, it is easy to lead to misdiagnosis and omission of diagnosis in primary healthcare institutions. Computer-aided diagnosis system can realize rapid screening of pneumoconiosis in order to assist clinicians in identification and diagnosis, and improve diagnostic efficacy. As an important branch of deep learning, convolutional neural network (CNN) is good at dealing with various visual tasks such as image segmentation, image classification, target detection and so on because of its characteristics of local association and weight sharing, and has been widely used in the field of computer-aided diagnosis of pneumoconiosis in recent years. This paper was categorized into three parts according to the main applications of CNNs (VGG, U-Net, ResNet, DenseNet, CheXNet, Inception-V3, and ShuffleNet) in the imaging diagnosis of pneumoconiosis, including CNNs in pneumoconiosis screening diagnosis, CNNs in staging diagnosis of pneumoconiosis, and CNNs in segmentation of pneumoconiosis foci to conduct a literature review. It aims to summarize the methods, advantages and disadvantages, and optimization ideas of CNN applied to the images of pneumoconiosis, and to provide a reference for the research direction of further development of computer-aided diagnosis of pneumoconiosis.