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1.
目的:了解建德市基层医院儿科门诊进行X线扫描治疗中,家属对X射线检查的知情同意与接受现状。方法:随机抽取建德市属3家公立综合性医院共60位接受X线扫描的儿童患者家属为调查对象,发放自制调查问卷并统计分析。结果:55位(91.67%)患者表示治疗前主治医生只告知了X射线是诊断性检查,没有具体告知X射线的危害性;18位(30%)的患者家属不清楚辐射会对人体有损害,42位(70%)不清楚或不注意辐射警示标志,更不会主动要求防护措施,学历水平较高者及有从事医务工作背景者接受X射线检查的为12人(20%),明显低于学历水平低者或没有从事医务工作背景者的46人(76.67%),不知可否接受的有2人(3.33%)(P<0.001)。结论:基层医院儿科诊断性X射线扫描前的知情同意告知仍需加强,儿科放射检查偏多,应避免并加强宣传和教育。  相似文献   
2.
PurposeFew investigations have examined the production of single restorations using intraoral scanners (IOS). Data on full-arch scans are rare, and data regarding torsion within the entire arch are very sparsely reported. Therefore, the aim of this study was to examine the deviations of torsion and linear distances in full-arch scans of three IOS based on different scanning principles.MethodsA cobalt-chrome-molybdenum alloy master model (CCMM) with four hemispheres was fabricated by laser sintering. The CCMM was digitized using a laboratory scanner (ATOS-Core/GOM) and scanned with three IOS (Omnicam/Sirona(OC); True Definition/3M(TD); TriosII/Cara-Version/Kulzer(TR)). All scan data were exported in a standard STL-file format and were analyzed with GOM Inspect software (V7.5/GOM). Torsion between the right and left side of the arch and linear accuracy (trueness and precision) were evaluated. After normality was confirmed, all data were subjected to parametric statistical analyses.ResultsThe torsion ranged from 0.07 ± 0.03°(OC) to 0.29 ± 0.14°(TD). Pairwise comparisons showed significant differences between the OC and TD scanners and between the TR and TD scanners. The linear distances ranged from 6 ± 5 μm(OC) to 298 ± 317 μm(TD). Significant differences were observed among all investigated IOS (p = 0.05).ConclusionsAlthough the highest torsion was observed for the TD scanner, it is still not clear whether the differences between the IOS are related to the scanning principle or to the scanning algorithm. Due to the high clinical relevance of full-arch restorations, future studies should consider torsion. Regarding linear accuracy, no general difference related to the scanning principles of the IOSs was observed.  相似文献   
3.
4.
目的 本研究使用激光扫描检眼镜(SLO)评价双侧中央暗点患者使用棱镜后的眼球运动反应.方法 本预试验共招募6例有双侧中央暗点的年龄相关性黄斑变性(AMD)患者以及6例正常视力的志愿者.首先用Nidek MP-1微视野仪确认患者的中央暗点和优选视网膜注视点(PRL),然后用Rodenstock SLO,在将视标投射在优选视网膜注视点时拍下实时视网膜像,接着在受检者眼前加入6~8 PD的棱镜,要求受检者保持注视视标,这时通过视网膜标记来测量视网膜像的移位量,以及随后发生的优选视网膜注视点的再次注视.过程中平均移位量和再次注视时间通过图像软件(ImageJ software)来计算.结果 实验组再次注视时的移位量在3个像素点或11.66个弧分之内(x轴:2.90±3.92,y轴:2.53±4.18).对照组再次注视时的移位会准确些(x轴:0.33±1.15,y轴:0.89±2.50),但与实验组差异无统计学意义(tx=1.32,Px>0.05;ty=0.80,Py>0.05).对照组再次注视时间(0.98±0.19)s较实验组(2.83±1.63)s要短,差距有统计学意义(t=5.03,P<0.01).其中有1例实验组受检者没有发生再次注视,其结果被排除并单独分析.结论 研究发现,双眼中央暗点患者对棱镜物像转移后的再注视反应与正常人接近,但实验组再注视明显较对照组慢,并有1例受检者没有发生再注视.该数据说明双侧中央暗点患者无论眼前有没有棱镜,都会利用相同的视网膜位置视物,因此,通过棱镜物像再定位的意义不大.  相似文献   
5.

Background/purpose

Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.

Methods

From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.

Results

Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).

Conclusions

WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.

Level of Evidence

IV.

Type of Study

Diagnostic Study.  相似文献   
6.
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices.  相似文献   
7.
目的:探讨螺旋CT多时相扫描对肝细胞癌和血管瘤的鉴别诊断。材料和方法:对37例患者(肝癌16例,血管瘤21例)行螺旋CT平扫和增强扫描,分析其表现。结果:37例平扫均发现低密度灶。肝细胞癌在动脉期75%有显著增强,呈高密度,在门静脉期和延迟期则呈低密度;血管瘤54%动脉期有典型增强表现,门静脉期100%有增强,24%全部填充,延迟期91%为高密度或等密度。结论:肝细胞癌和血管瘤在螺旋CT多时相增强扫描中,各有其典型的CT表现,两者鉴别的关键是门静脉期。  相似文献   
8.
采用流变学法测定了亚麻籽胶溶液的胶凝点、熔化点,并采用质构仪、扫描电镜和原子力显微镜等手段研究了影响亚麻籽胶凝胶强度的因素,结果表明亚麻籽胶具有胶凝性,它能形成一种热可逆的冷致凝胶,亚麻籽胶溶液的胶凝点低于其凝胶的熔化点,且亚麻籽胶溶液的胶凝点及其凝胶的熔化点均随冷却的起始温度的升高而升高。亚麻籽胶浓度、溶解温度、pH、NaCl、CaCl2及复合磷酸盐能影响亚麻籽胶的凝胶强度,亚麻籽胶的凝胶强度随着浓度的增加及溶解温度的升高而增强;在pH6~9的范围内,亚麻籽胶的凝胶强度达到最大;NaCl和复合磷酸盐可以降低亚麻籽胶的凝胶强度,低浓度(〈0.3%)的CaCl2可以增强亚麻籽胶的凝胶强度,而高质量分数(〉0.3%)的CaCl2能降低亚麻籽胶的凝胶强度。  相似文献   
9.
用SEM观察6种复合树脂充填物与酸蚀牙齿间密合度。结果表明6种复合树脂充填物与牙齿间均有微缝隙,其宽度多数在5μm内,最宽为10~15μm。1月后再观察,清晰见到从酸蚀牙本质小管曳出的树脂突,其曳出方向与缝隙形成可能有关。  相似文献   
10.
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