简介:背景:临床中寰枢椎椎弓根螺钉准确置入有一定难度。目前,辅助寰枢椎椎弓根钉置钉的方法众多,但大多存在设计、操作使用繁琐复杂等问题。目的:总结分析3D打印及术前数字化设计辅助椎弓根置钉治疗寰枢椎不稳的临床疗效。方法:本研究纳入2014年8至2017年12月使用术前数字化设计及3D打印技术辅助置钉治疗的14例寰枢椎不稳患者,男8例,女6例,年龄26~67岁,平均(47.3±13.8)岁。陈旧性骨折5例,齿状突畸形8例,类风湿性关节炎1例。术前将患者的寰枢椎CT数据导入Mimics17.0软件,生成三维模型,数字化设计椎弓根螺钉的最佳钉道并生成相应文件,测量记录进钉点的位置及钉道的内倾角、头倾角数据。通过3D打印机打印实物模型。在实物模型上模拟置钉。术中根据术前设计完成螺钉通道,攻丝后置入螺钉。术后行CT扫描比较手术前后内倾角、头倾角变化,并进行螺钉位置分级,评价螺钉准确性。随访确定患者恢复情况。结果:14例患者均顺利完成手术,手术时间110~200min,平均(146±34)min;术中出血量150~300ml,平均(213±45)ml;透视5~11次,平均(7.4±1.5)次;术后拔管前引流总量90~200ml,平均(140±34)ml。共置入56枚螺钉。螺钉准确性:0级占94.6%(53/56),Ⅰ级占5.4%(3/56),Ⅱ、Ⅲ级为0。手术前后螺钉内倾角和头倾角相比差异均无统计学意义(P〉0.05)。随访8~36个月,平均(18.6±8.1)个月。无椎动脉、神经损伤及感染等出现。至末次随访均植骨融合,VAS评分从术前(3.9±1.1)分(3~6分)降至(0.9±0.6)分(0~2分),9例术前脊髓功能FrankelD级患者均恢复至E级。结论:通过3D打印及术前数字化设计辅助寰枢椎不稳治疗,方法简便,可充分了解局部情况,指导手术,提高置钉准确性。
简介:摘要针对近景数码影像的三维重建问题,本文介绍了一种基于数字摄影测量PhotoModeler软件的可量测三维重建技术。以非量测型数码相机采集多视角影像,采用二维平面格网完成数码相机检校,通过手工交互式方式实现特征提取、影像匹配等处理,进而建立起目标物体的可量测三维模型,该模型为后续的三维漫游和量测等提供基础数据。
简介:3Dprintingisdisruptingthedesignandmanufactureofelectronicproducts.3Dprintingelectronicsoffersgreatpotentialtobuildcomplexobjectwithmultiplefunctionalities.Particularly,ithasshowntheuniqueabilitytomakeembeddedelectronics,3Dstructuralelectronics,conformalelectronics,stretchableelectronics,etc.3Dprintingelectronicshasbeenconsideredasthenextfrontierinadditivemanufacturingandprintedelectronics.Overthepastfiveyears,alargenumberofstudiesandeffortsregarding3Dprintingelectronicshavebeencarriedoutbybothacademiaandindustries.Inthispaper,acomprehensivereviewofrecentadvancesandsignificantachievementsin3Dprintingelectronicsisprovided.Furthermore,theprospects,challengesandtrendsof3Dprintingelectronicsarediscussed.Finally,somepromisingsolutionsforproducingelectronicswith3Dprintingarepresented.
简介:X-rayimagingistheconventionalmethodfordiagnosingtheorthopedicconditionofapatient.ComputerizedTomography(CT)scanningisanotherdiagnosticmethodthatprovidespatient’s3Danatomicalinformation.However,bothmethodshavelimitationswhendiagnosingthewholeleg;X-rayimagingdoesnotprovide3Dinformation,andnormalCTscanningcannotbeperformedwithastandingposture.Obtaining3Ddataregardingthewholeleginastandingpostureisclinicallyimportantbecauseitenables3Danalysisintheweightbearingcondition.Basedontheseclinicalneeds,ahardware-basedbi-planeX-rayimagingsystemhasbeendeveloped;itusestwoorthogonalX-rayimages.However,suchmethodshavenotbeenmadeavailableingeneralclinicsbecauseofthehightcost.Therefore,weproposedawidelyadaptivemethodfor2DX-rayimageand3DCTscandata.Bythismethod,itispossibletothreedimensionallyanalyzethewholeleginstandingposture.TheoptimalpositionthatgeneratesthemostsimilarimageisthecapturedX-rayimage.Thealgorithmverifiesthesimilarityusingtheperformanceoftheproposedmethodbysimulation-basedexperiments.Then,weanalyzedtheinternal-externalrotationangleofthefemurusingrealpatientdata.Approximately10.55degreesofinternalrotationswerefoundrelativetothedefinedanterior-posteriordirection.Inthispaper,wepresentausefulregistrationmethodusingtheconventionalX-rayimageand3DCTscandatatoanalyzethewholelegintheweight-bearingcondition.