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  • Pancreatic neuroendocrine neoplasm: current status and advancement in imaging

    ObjectiveTo summarize the status and progress of imaging studies of pancreatic neuroendocrine neoplasms (pNENs).MethodThe relevant literatures published recently at domestic and abroad about the imaging of pNENs were collected and reviewed.ResultsDue to poor visibility of pancreatic body and tail, the application of ultrasound (US) was limited. Compared with US, endoscopic ultrasound (EUS) and contrast-enhanced ultrasound (CEUS) could improve the detection rate of pNENs. The ability of plain CT scans to differentiate pathological grades was still controversial, but the value of enhanced scan was higher. CT texture analysis was feasible in the discrimination of nonhypervascular pNENs and pancreatic ductal adenocarcinoma (PDAC). Teta2 was the parameter with the highest diagnostic performance. The enhanced features of MRI were similar to CT. Combined with the apparent diffusion coefficient (ADC) value, the diagnostic and classification capabilities of MRI were improved, and the sensitivity and specificity of different ADC thresholds were also different. 68Ga-tetraazacyclododecane tetraacetic acid (68Ga-DOTA) peptide PET-CT had good preliminary diagnostic value for well-differentiated pNENs, and 18Fluoro-fluorodeoxyglucose (18F-FDG) PET-CT had limited diagnostic value.ConclusionsSomatostatin receptor imaging is of high diagnostic value and can guide clinical treatment and predict prognosis, but it has not been widely used in China. Conventional morphological images have advantages in the diagnosis and classification of pNENs. Therefore, it is important to choose a proper image inspection method.

    Release date:2020-04-28 02:46 Export PDF Favorites Scan
  • CHOROIDAL VASCULAR CHANGES IN SEVERE CONTUSION OF THE RABBIT EYE

    The pathogensis of choroidal vascular changes in traumatic rtinopethy remains uncertain.We performed scanning electron micrmcopie (SEM) observation of methyl methalerylare vascular corrosion casts in a rabbi model with severe retinal contusion. Areas of filling defects in corrosion casts of the choriocapillaries, correspending to the areas of impact retinal lesions were noted in the traumatized eyes one to 28 days after trauma.No neovascularization was found in the eyes 56 days after trauma. The results confirm that obstruction and disappearance of involved choriocapillaries are the main changes of choroidal vasculatrue in severe blunt tram. The changes may be associated with continuous necrosis, of the photoreceptors 4 weeks after injury. (Chin J Ocul Fundus Dis,1993,9:5-7)

    Release date:2016-09-02 06:35 Export PDF Favorites Scan
  • Clinical characteristics and features of images of optical coherence tomography in vitreomacular traction syndrome

    ObjectiveTo observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with vitreomacular traction syndrome and its clinical significance.MethodsThe clinical data of 25 patients with vitreomacular traction syndrome diagnosed by OCT, fundus fluorescein angiography, and B-scan ultrasonography and confirmed by surgical treatment were retrospectively analyzed. The features of images of OCT in vitreomacular traction syndrome were observed.ResultsFive types were found in the images of OCT in the patients with vetreomacular traction syndrome. The main characteristic of the images of OCT in the patients with vitreomacular traction was the highly reflective band of the vitreous posterior cortex inservion at fovea. In 25 patients, vitreomacular traction associated with macular edema was found in 10, macular hole in 3, macular epiretinal membrane in 6, retinoschisis in 1, and retinal detachment in 5.ConclusionOCT is a potential powerful toll for detecting and monitoring vitreomacular traction syndrome. (Chin J Ocul Fundus Dis, 2005,21:86-89)

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
  • 核素扫描为假阴性原发性甲状旁腺功能亢进症手术时机及治疗策略的把握

    目的结合临床病例分析原发性甲状旁腺功能亢进症(PHPT)患者行 99锝m-甲氧基异丁基异腈(99Tcm-MIBI)SPECT/CT 核素扫描结果为假阴性的原因,为在临床工作中核素扫描结果为假阴性或与其他影像学定位结果不一致的 PHPT 患者提供把握手术时机及治疗策略的思路。方法回顾性分析吉林大学第一医院甲状腺外科收治的 4 例核素扫描结果为假阴性的 PHPT 患者的临床病理资料。结果PHPT 患者甲状旁腺病灶的大小、是否伴有出血、坏死、囊性变以及是否为恶性肿瘤伴发广泛转移都可导致 99Tcm-MIBI SPECT/CT 呈现假阴性结果。结论99Tcm-MIBI SPECT/CT 扫描结果不能作为 PHPT 是否行手术治疗的判定标准,在临床工作中当 99Tcm-MIBI SPECT/CT 结果呈现假阴性或与其他影像学定位结果不一致时,应结合患者实验室检查及其他影像学检查结果综合考虑,定位病灶,避免临床误诊,把握好手术时机以避免遗漏多发甲状旁腺病灶,减少不必要的双侧颈部探查,提高手术成功率。

    Release date:2020-07-26 02:35 Export PDF Favorites Scan
  • Optical coherence tomography in macular edema

    Objective To observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with macular edema, and investigate relationship between the retinal thickness at the central fovea and the best corrected visual acuity. Methods Fourty-seven patients (54 eyes) with macular edema diagnosed by direct and indirect ophthalmoscopy, three mirror contactlens, or fundus fluorescein angiography (FFA) underwent OCT which was also performed on 50 healthy individuals as the control. The examination focused on the horizontal and vertical planes crossing the central fovea to measure the thickness of the fovea. The correlation between retinal thickness at the central fovea and best-corrected visual acuity was analyzed, and the images of OCT in the patients with macular edema were classified according to the macular configuration. Results Significant difference of the macular configuration and best-corrected visual acuity was found between the control and macular edema group. Three characteristics were found in the images of OCT in the patients with macular edema: sponge-like retinal swelling in 20 eyes (37.1%), macular cystoid edema in 26 eyes (48.1%), and serous retinal detachment in 8 eyes (14.8%). The statistical analysis showed that there was a negative correlation between the thickness at the central fovea and best-corrected visual acuity of affected eyes (r=-0.569, P=0.000). Conclusions The images of OCT in macular edema include 3 types: sponge-like retinal swelling, macular cystoid edema, and serous retinal detachment. The retinal thickness at the central fovea of the eyes with macular edema was thicker than that of the normal ones, and the thicker the fovea is, the poorer the visual acuity will be. (Chin J Ocul Fundus Dis,2004,20:152-155)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • CALCULATION OF ARTICULAR SURFACE AREA OF OSTEONECROSIS AND ITS APPLICATION IN PREDICTING COLLAPSE OF THE FEMORAL HEAD

    Objective To explore the program for calculating the necrotic articular surface area (NASA) and the ratio of NASA to whole articular surface area (WASA) of osteonecrosis of the femoral head (ONFH), to verify the accuracy of this calculation and to predict the collapse of the femoral head clinically using this program. Methods From June 2001 to June 2003, The specimens of the necrotic femoral head from eight patients (13 hips) were obtained by total hip arthroplasty. The magnetic resonance imaging (MRI) was taken in all patients before operation. According to a series of T1-weight pictures, the NASA and the ratio of NASA to WASA were calculated by designing program. The specimens of the necrotic femoral head were sawed into lays similar to MRI pictures using the coordinate paper stick on the auricular surface, the data processing were done by analytic instrument for pictures. The data of both were analyzed statistically by software SPSS 10.0 edition. The NASA and the ratio of NASA to WASA were calculated on MRI in ARCO Stage Ⅰ, Ⅱ 16 patients (25 hips) with non-operation. Follow-up was done to the patients with collapse of the femoral head and to the patients with no collapse for at least 24 months. The data were compared in collapse group and non-collapse group. Results There were no significant differences between MRI pictures calculation and specimens measurement (NASA: 0.412, ratio of NASA to WASA: 0.812, Pgt;0.05). Of the 25 hips followed up, collapse occurred in 17 hips. NASA was 31.06±8.10 cm2, (95% CI: 26.58 to 35.55),the ratio of NASA to WASA was 58.91%±15.11%, (95% CI: 51.14to 66.68). No collapse appeared in 8 hips. NASA was 14.16±9.32 cm2(95% CI: 6.04 to 21.95), the ratio of NASA to WASA was 29.48%±19.76%(95% CI: 12.97to 45.99). The ratio in the patients with collapse was beyond 33%. Conclusion The NASA and the ratio of NASA to WASA in patients withONFH can be accurately calculated with the MRI pictures. The possibility of collapse can be predicted by this method. As it is complicated in operation, improvement should be made in order to put itinto clinical use.

    Release date:2016-09-01 09:30 Export PDF Favorites Scan
  • Diagnostic Value and Post-operative Evaluation of MRA and CTA in Vascular Lesions of Low Extremity Caused by Crush Injury after Earthquake

    目的:探讨磁共振血管造影(MRA)以及计算机断层扫描血管成像(CTA)对地震挤压伤下肢血管病变的临床价值。方法:对5·12汶川大地震中我院收治的已确诊为地震挤压伤致双下肢横纹肌溶解症3例患者进行双下肢MRA检查,并对严重挤压伤及下肢毁损,并行截肢的另三名患者进行术后CTA检查。对MRA图象双下肢动脉进行回顾性分析,总结MRA征象,同时总结截肢术后患者CTA表现及临床价值,并评价二者检查在挤压伤所至横纹肌溶解症的临床诊治中的作用。结果:3例未行截肢患者MRA双下肢主要动脉未见确切狭窄及闭塞征象,管腔内未见充盈缺损影。3例已行截肢患者可见残余肢体的明显肿胀,双侧髂血管以及部分截断肢体远端血管内见止血弹簧钢圈影像,部分截断肢体远端动脉分支变细。截断血管未见再通,周围无渗血改变。结论:MRA、CTA能直观显示双下肢动脉损伤及术后情况,在临床应用中各有优势和局限性。对二者的合理选择能为临床诊治提供有利信息。

    Release date:2016-09-08 09:54 Export PDF Favorites Scan
  • Optic coherence tomography for congenital juvenile macular retinoschisis

    ObjectiveTo observe the characteristics of images of optic coherence tomography (OCT) for the macular region of congenital retinoschisis and investigate its significance.MethodsThe data of OCT of 11 patients (20 eyes) with congenital macular retinoschisis diagnosed by direct or preplacedmirror ophthalmoscopy, fundus fluorescein angiography (FFA), and electroretinography (ERG) were retrospectively analyzed.ResultsThe images of OCT showed split in the mid portion of sensory retina at the macula in all eyes. The retina of fovea centralis was divided by the split into two slightly thickening layers. In addition, in a few number of cases, the parafoveal sensory retina which became much thickening with 2 splits, was divided into 3 layers.ConclusionThe characteristic of images of OCT in macular congenital retinoschisis is the split cavity at the middle layer of the retina, and OCT has a high sensitivity in the diagnosis of congenital retinoschisis. (Chin J Ocul Fundus Dis, 2005,21:93-96)

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
  • 黄斑裂孔直径测量,光相干断层扫描首选水平扫描还是放射状扫描?

    Release date:2025-05-14 02:04 Export PDF Favorites Scan
  • Application of Dual-source Low-dose Computed Tomography in Common Chest Inspection

    目的 探讨双源CT低剂量扫描技术在胸部普通检查中的应用价值。 方法 将2011年8月-2012年12月收治的875例患者依次分为7组,分别采用常规管电流量110 mAs和低管电流量105、100、95、90、85、80 mAs测量,计算并评估7组患者纵隔窗图像的胸骨前空气CT值标准差(SD空气)、肺动脉分叉平面肺动脉信噪比、降主动脉信噪比、肺动脉-竖脊肌对比噪声比、降主动脉-竖脊肌对比噪声比;纵隔窗图像和肺窗图像主观质量评分以及射线剂量指标:CT剂量指数(CTDI)、剂量长度乘积(DLP)、有效剂量(ED)。 结果 7组患者纵隔窗图像肺动脉信噪比、降主动脉信噪比、图像主观质量评分和射线剂量CTDI、DLP、ED之间差异均有统计学意义(P<0.05);肺动脉-竖脊肌对比噪声比、降主动脉-竖脊肌对比噪声比之间差异无统计学意义(P>0.05);其中第7组图像信噪比、射线剂量和主观质量评分均为最低,部分图像肩背部出现横条状伪影,影响肺尖部病变的显示,难以提供足够的诊断信息。 结论 胸部普通CT检查,通过阶段性降低管电流量使诊断医生逐渐适应低剂量图像质量,从而普及现有设备的低剂量扫描的方法是可行的。双源CT采用85 mAs的参考管电流量,既能获得满足临床诊断的合格图像,又能明显降低患者群体接受的辐射剂量。

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