非线性融合技术在头颈部CTA中的价值:体模实验

目的 探讨双源双能量CT非线性融合（NLB）技术提高头颈部CTA图像质量、降低辐射剂量的应用价值。方法 分别以常规120 kV （螺距为1.0）及双能量80/Sn140 kV （螺距分别为0.5、0.8、1.0和1.2）对人体头颈部仿真体模进行扫描,并对双能量扫描数据进行线性融合（LB）和NLB处理。比较9组图像颈内动脉、大脑中动脉的CT值、CNR和图像质量主观评分的差异;比较不同扫描条件下辐射剂量的差异。结果 螺距为0.5、0.8、1.0、1.2的NLB图像中,大脑中动脉和颈内动脉的CT值大于螺距为0.5、0.8、1.0、1.2的LB图像和常规120 kV图像（P均<0.05）。螺距为0.5和0.8的NLB图像中,大脑中动脉和颈内动脉的CNR大于螺距为1.0、1.2的NLB图像,螺距为0.5、0.8、1.0、1.2的LB图像和常规120 kV图像（P均<0.05）。主观评价显示,双能量扫描螺距为0.5时,图像质量最佳;双能量扫描螺距为0.8时,LB、NLB图像与常规120 kV图像评分相当。与常规120 kV扫描方式比较,双能量扫描螺距为0.8、1.0和1.2时,有效剂量分别降低36.12%、46.28%和53.22%。结论 NLB技术可在保证头颈部CTA图像质量的同时降低辐射剂量。     

虚拟现实技术在截肢后幻肢痛患者中的应用及效果观察

目的探讨虚拟现实技术对缓解截肢患者幻肢疼痛的作用及效果。方法选取2017年1月-2019年1月在我院骨科因外伤行单侧下肢切除术后幻肢痛的患者80例,采用随机数表法分为对照组和观察组,各40例,对照组行常规护理,观察组在对照组基础上应用虚拟现实技术。比较两组患者疼痛情况(幻肢痛次数、疼痛分级指数、VAS视觉模拟评分、现时疼痛强度评定分数)、焦虑评分及舒适度。结果观察组幻肢痛次数、疼痛分级指数、VAS视觉模拟评分、现时疼痛强度评定分数均低于对照组,差异有统计学意义(P<0.05)。术前、术后两组患者焦虑评分组间比较,差异均无统计学意义(P>0.05);对照组术后焦虑评分高于术前,差异有统计学意义(P<0.05);观察组手术前后焦虑评分比较,差异无统计学意义(P>0.05)。术后两组舒适度评分均高于术前,且观察组术后舒适度评分显著高于对照组,差异有统计学意义(P<0.05)。结论应用虚拟现实技术可有效降低截肢后患者幻肢痛次数及疼痛程度,提高患者舒适度。     

Psychological indices and phantom shocks in patients with ICD

Introduction Some patients with ICDs experience the sensation of a shock in the absence of true therapy (phantom shock). We hypothesize that phantom shocks may be a manifestation of anxiety, depression or PTSD.Methods and results All patients over 18 years old with an ICD were eligible to enroll in the study. The first 75 subjects who agreed to participate were enrolled and divided into three groups: ICD patients with phantom shocks (n = 19); ICD patients who had actual shocks (n = 28) and ICD patients who had no shocks (n = 28). During a clinic visit a demographic questionnaire and three psychological rating scales were administered: the Spielberger State–Trait Anxiety Inventory (STAI); the Center for Epidemiologic Studies Depression Scale (CES-D) and the Posttraumatic Stress Checklist (PCL-C). No significant differences between groups were found in gender, race, age, history of MI or cardiac surgery status. Data analysis of the psychological indices using one-way ANOVA showed that the group with phantom shocks had more depression (CES-D p = 0.011) and more anxiety (STAI p = 0.010) than the other groups. Multiple comparisons of group means showed a greater percentage of clinically depressed patients in the phantom shock group than in the other groups.Conclusion Patients with phantom shocks are more likely to be clinically depressed and have higher levels of anxiety than other ICD patients, regardless of history of actual shocks.This publication was partially supported by Grant number K30-AT-00060 from the National Center for Complementary and Alternative Medicine (NCCAM). Its contents are solely the responsibility of the authors and do not necessarily represent the officicial views of the NCCAM or the National Institutes of Health.     

Interventional pain management for phantom limb pain: An algorithmic approach

Phantom limb pain is a type of chronic pain existing in different organs, not just limbs. The incidence is very high in the postamputation period and treatment can be a challenge. The pharmaceutical treatment strategies in addition to psychological rehabilitative strategies and interventional management play a successful role in the management of these patients. For this article, we conducted a review of literature about pain management for phantom limb pain to identify the treatment modalities, which involved interventional pain management, and an algorithmic approach is proposed.     

Assessing the Imaging Capabilities of Radial Mechanical and Electronic Echo-endoscopes Using the Resolution Integral

Over the past decade there have been significant advances in endoscopic ultrasound (EUS) technology. Although there is an expectation that new technology will deliver improved image quality, there are few methods or phantoms available for assessing the capabilities of mechanical and electronic EUS systems. The aim of this study was to investigate the possibility of assessing the imaging capability of available EUS technologies using measurements of the resolution integral made with an Edinburgh Pipe Phantom. Various radial EUS echo-endoscopes and probes were assessed using an Edinburgh Pipe Phantom. Measurements of the resolution integral (R), depth of field (L_R) and characteristic resolution (D_R) were made at all operating frequencies. The mean R value for Fuji miniprobes was 16.0. The GF-UM20 and GF-UM2000 mechanical radial scopes had mean R values of 24.0 and 28.5, respectively. The two electronic radial echo-endoscopes had similar mean R values of 34.3 and 34.6 for the Olympus GF-UE260 and Fujinon EG-530 UR scopes, respectively. Despite being older technology, the mechanical GF-UM2000 scope had superior characteristic resolution (D_R), but could not compare with the depths of field (L_R) delivered by the current generation of electronic radial scopes, especially at the standard operating frequencies of 7.5 and 12 MHz.     

High-Definition Computed Tomography for Coronary Artery Stent Imaging: a Phantom Study

Objective

To assess the performance of a high-definition CT (HDCT) for imaging small caliber coronary stents (≤ 3 mm) by comparing different scan modes of a conventional 64-row standard-definition CT (SDCT).

Materials and Methods

A cardiac phantom with twelve stents (2.5 mm and 3.0 mm in diameter) was scanned by HDCT and SDCT. The scan modes were retrospective electrocardiography (ECG)-gated helical and prospective ECG-triggered axial with tube voltages of 120 kVp and 100 kVp, respectively. The inner stent diameters (ISD) and the in-stent attenuation value (AV_in-stent) and the in-vessel extra-stent attenuation value (AV_in-vessel) were measured by two observers. The artificial lumen narrowing (ALN = [ISD - ISD_measured]/ISD) and artificial attenuation increase between in-stent and in-vessel (AAI = AV_in-stent - AV_in-vessel) were calculated. All data was analyzed by intraclass correlation and ANOVA-test.

Results

The correlation coefficient of ISD, AV_in-vessel and AV_in-stent between the two observers was good. The ALNs of HDCT were statistically lower than that of SDCT (30 ± 5.7% versus 35 ± 5.4%, p < 0.05). HDCT had statistically lower AAI values than SDCT (15.7 ± 81.4 HU versus 71.4 ± 90.5 HU, p < 0.05). The prospective axial dataset demonstrated smaller ALN than the retrospective helical dataset on both HDCT and SDCT (p < 0.05). Additionally, there were no differences in ALN between the 120 kVp and 100 kVp tube voltages on HDCT (p = 0.05).

Conclusion

High-definition CT helps improve measurement accuracy for imaging coronary stents compared to SDCT. HDCT with 100 kVp and the prospective ECG-triggered axial technique, with a lower radiation dose than 120 kVp application, may be advantageous in evaluating coronary stents with smaller calibers (≤ 3 mm).