82例颅颈连接部体层分析

目的：探讨颅颈连接部体层摄影的应用价值及影像特点。方法：对８２例颅颈连接部正侧位体层片汇总分析，正位片侧量枕骨髁关节面角度、齿状突位置及其与寰枢椎侧缘的对应关系、寰椎侧块的对称性；侧位片侧量寰椎前结节与齿状突的间隙，寰椎前弓与枕骨的关系。结果：正常２１侧（枕骨髁关节面角１０～２０°，齿状突偏移＜１．０ｍｍ，寰枢椎侧缘对称，寰齿间隙０．２ｍｍ且关节面平行），寰枕融合畸形２５例，寰枢椎脱位和／或骨折２８例，其它病变８例。结论：体层摄影可排除体位不正及结构重叠造成的Ｘ线平片假象，显示骨与关节的细节，提高颅颈连接部疾病的检出率。     

脑血管母细胞瘤的CT和MRI诊断

目的 分析血管母细胞瘤的CT、MRI影像特征及鉴别诊断。方法 30例经手术病理证实的血管母细胞瘤,19例行CT检查,11例MRI检查。结果 25例病灶位于幕下,5例位于幕上。单发28例,多发2例。囊结节型22例,囊肿型5例,实质肿块或混合型3例。CT平扫表现球形低密度影,囊腔壁结节和实质肿块均呈等密度或稍高于囊液密度。MRI示T1WI高于囊液信号,T2WI呈稍高或等信号。壁结节和实质肿块明显强化,强化密度曲线呈速升缓降型,MRI信号增强率升高并可见流空信号。结论 血管母细胞瘤有特征性,CT和MRI表现,CT动态增强扫描、密度曲线测定以及MRI增强率的表达有助于诊断和鉴别诊断。     

多层螺旋CT在骶管阻滞麻醉中的临床应用

目的 为骶管阻滞麻醉骶管裂孔穿刺点体表定位、进针方向及深度探索一种新的方法。方法 回顾性对8例盆腔扫描病人进行三维重建,测量骶管裂孔至拟注药点的距离及骶管裂孔大小;骶骨表面重建后对骶管裂孔、骶管的形状进行评估,确定进针方向。结果 全部病人经骶骨表面重建后能通过各种角度对骶管裂孔进行观察并测量骶管裂孔的大小,从骶正中嵴将骶骨切除一半后能对骶管的形状及走行进行精确的观察并准确测出了骶管裂孔至注药点的距离。利用上述数据术前在病人体表进行了准确定位,并成功实施了麻醉。结论 本方法可帮助医生对骶管裂孔进针方向、进针深度提供准确的数据。显著提高了麻醉手术的成功率,避免了给患者可能带来的副损伤,同时还可进行术前麻醉模拟训练。     

腹膜假性粘液瘤的CT诊断与鉴别诊断

目的 探讨腹膜假性粘液瘤的CT表现,提高对本病的诊断与鉴别诊断水平。方法 选取经手术及病理证实的腹膜假性粘液瘤8例,全部病例术前均行腹部CT平扫和增强检查;回顾分析其CT影像表现。结果 （1）典型CT表现：8例均出现腹、盆腔脏器扇贝形压迹;7例表现为腹腔、盆腔脏器周边的分房粘液团块,可多发或单发;单发/多发者其内密度均匀,CT值略高于水,增强后边缘性强化;囊壁厚度一致或不均。（2）不典型CT表现：3例可显示原发病灶及腹膜后淋巴结肿大。5例合并有网膜、肠系膜浸润性改变。7例合并有腹水;2例合并钙化。对于不典型CT表现,在CT征象上与其它非粘液癌性腹膜炎相仿,也较难鉴别。结论 CT检查对腹膜假性粘液瘤有重要的诊断和鉴别诊断价值。     

颅内海绵状血管瘤的影像学诊断

目的 探讨MRI、MRA和CT对颅内海绵状血管瘤的诊断价值。方法 回顾性分析经手术病理证实的颅内海绵状血管瘤26例患者的影像学资料。结果 26例中，16例行CT检查，23例行MRI检查，12例行MRA检查。所有病例都属脑内型，可位于脑内任何部位，单发病灶多见，周围无或轻度水肿。脑内型海绵状血管瘤MRI T2WI表现为桑椹状混杂高信号，周围有低信号环绕，增强后病灶大都无强化；MRA检查未见异常血管；CT平扫为稍高密度影。结论 颅内海绵状血管瘤的MRI表现较有特异性，综合MRI、MRA和CT表现可明确诊断。在颅内海绵状血管瘤的诊断方面MRI优于CT。     

早期蔺草尘肺的HRCT表现

目的：研究早期蔺草尘肺的HRCT表现。方法：对经高kVp胸片筛选后的47例蔺草作业工人作胸部HRCT扫描并分析CT表现,其中包括25例已被确诊尘肺和22例未能确诊尘肺者。结果：44例显示弥漫性分布的类圆形“P”小结节阴影,包括高kVp胸片尚难以确诊蔺草尘肺的22例,3例上肺野出现大阴影及间质性纤维化。结论：早期的蔺草尘肺结节在肺小叶内呈随机分布,并非仅在小叶中心,细支气管壁和小叶间隔未见增厚,HRCT对显示弥漫性尘肺结节灶及肺间质性改变明显优于胸片。     

CT扫描参数最优化 儿童患者辐射剂量最少化

儿童患者在CT检查中怎样有效减少辐射剂量,同时又能保证图像质量,作为从事放射工作人员应该充分认识。本文从CT检查辐射的危害性,优化扫描参数及降低GT检查辐射剂量的途径等方面加以综述。     

儿童肾脏非霍奇金淋巴瘤的CT诊断价值

目的探讨儿童肾脏非霍奇金淋巴瘤CT平扫及增强表现,提高对该病的认识。方法回顾性分析50例经手术或活检病理证实的儿童肾脏非霍奇金淋巴瘤(原发性1例,继发性49例)CT表现。结果 50例儿童肾脏非霍奇金淋巴瘤影像学表现多样,根据CT表现可分为5型:多发结节型、单发结节型、弥漫浸润型、邻近后腹膜淋巴瘤侵犯型及肾周肿块型。本组36例多发结节型,其中双侧多发34例,单侧多发2例;8例单发结节型,其中右侧单发6例,左侧单发2例;3例弥漫浸润型;2例邻近后腹膜淋巴瘤侵犯型;1例肾周肿块型。结论儿童肾脏非霍奇金淋巴瘤CT表现形式多样,但具有一定特征,对于准确诊断儿童肾脏非霍奇金淋巴瘤,指导临床分期、制定治疗方案及观察疗效具有重要意义。     

Neural network-based computer-aided diagnosis in distinguishing malignant from benign solitary pulmonary nodules by computed tomography

Background Computer-aided diagnosis (CAD) of lung cancer is the subject of many current researches. Statistical methods and artificial neural networks have been applied to more quantitatively characterize solitary pulmonary nodules (SPNs). In this study, we developed a CAD scheme based on an artificial neural network to distinguish malignant from benign SPNs on thin-section computed tomography (CT) images, and investigated how the CAD scheme can help radiologists with different levels of experience make diagnostic decisions.Methods Two hundred thin-section CT images of SPNs with proven diagnoses (135 small peripheral lung cancers and 65 benign nodules) were analyzed. Three clinical features and nine CT signs of each case were studied by radiologists, and the indices of qualitative diagnosis were quantified. One hundred and forty nodules were selected randomly to form training samples, on which the neural network model was built. The remaining 60 nodules, forming test samples, were presented to 9 radiologists with 3–20 years of clinical experience, accompanied by standard reference images. The radiologists were asked to determine whether a nodule was malignant or benign first without and then with CAD output. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis.Results CAD outputs on test samples had higher agreement with pathological diagnoses (Kappa=0.841, P<0.001). Compared with diagnostic results without CAD output, the average area under the ROC curve with CAD output was 0.96 (P<0.001) for junior radiologists, 0.94 (P=0.014) for secondary radiologists and 0.96 (P=0.221) for senior radiologists, respectively. The differences in diagnostic performance with CAD output among the three levels of radiologists were not statistically significant (P=0.584, 0.920 and 0.707, respectively). Conclusions This CAD scheme based on an artificial neural network could improve diagnostic performance and assist radiologists in distinguishing malignant from benign SPNs on thin-section CT images.     

CT联合超声诊断POEMS综合征

目的探讨POEMS综合征CT和超声影像学表现特点,提高认识能力。方法选取4例经CT和超声诊断的POEMS综合征患者临床资料,分析影像学表现。结果 4例均为男性,CT表现4例腋窝、腹股沟淋巴结多发肿大,3例纵隔淋巴结肿大,增强扫描呈明显均匀强化,超声显示淋巴结内部及周围血流丰富;4例多浆膜腔积液;3例脊柱、骨盆、胸骨多发局限性骨质硬化;3例乳腺发育;3例肺动脉高压。结论骨质硬化性改变、多中心富血供淋巴结肿大、肺动脉高压在POEMS综合征有一定影像学特点,密切结合临床可做出正确诊断。