Evaluating the contribution of satellite measurements to the reconstruction of three-dimensional ocean temperature fields in combination with Argo profiles

Assimilation systems absorb both satellite measurements and Argo observations.This assimilation is essential to diagnose and evaluate the contribution from each type of data to the reconstructed analysis,allowing for better configuration of assimilation parameters.To achieve this,two comparative reconstruction schemes were designed under the optimal interpolation framework.Using a static scheme,an in situ-only field of ocean temperature was derived by correcting climatology with only Argo profiles.Through a dynamic scheme,a synthetic field was first derived from only satellite sea surface height and sea surface temperature measurements through vertical projection,and then a combined field was reconstructed by correcting the synthetic field with in situ profiles.For both schemes,a diagnostic iterative method was performed to optimize the background and observation error covariance statics.The root mean square difference(RMSD)of the in situ-only field,synthetic field and combined field were analyzed toward assimilated observations and independent observations,respectively.The rationale behind the distribution of RMSD was discussed using the following diagnostics:(1)The synthetic field has a smaller RMSD within the global mixed layer and extratropical deep waters,as in the Northwest Pacific Ocean;this is controlled by the explained variance of the vertical surface-underwater regression that reflects the ocean upper mixing and interior baroclinicity.(2)The in situ-only field has a smaller RMSD in the tropical upper layer and at midlatitudes;this is determined by the actual noise-to-signal ratio of ocean temperature.(3)The satellite observations make a more significant contribution to the analysis toward independent observations in the extratropics;this is determined by both the geographical feature of the synthetic field RMSD(smaller at depth in the extratropics)and that of the covariance correlation scales(smaller in the extratropics).

Three-Dimensional Measurement and Reconstruction of Fabric Drape Shape

This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics.

A method for phase reconstruction in optical three-dimensional shape measurement

In optical three-dimensional shape measurement, a method of improving the measurement precision for phase reconstruction without phase unwrapping is analyzed in detail. Intensities of any five consecutive pixels that lie in the x-axis direction of the phase domain are given. Partial derivatives of the phase function in the x- and y-axis directions are obtained with a phase-shifting mechanism, the origin of which is analysed. Furthermore, to avoid phase unwrapping in the phase reconstruction, we derive the gradient of the phase function and perform a two-dimensional integral along the x- and y-axis directions. The reconstructed phase can be obtained directly by performing numerical integration, and thus it is of great convenience for phase reconstruction. Finally, the results of numerical simulations and practical experiments verify the correctness of the proposed method.

Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology

Objective To discuss the measurement of bone tumor volume on the basis of three dimensional images segmentation technology. Methods Twenty patients with lacunar bone tumor from Tianjin Hospital and Tongji Hospital were included in the

Diameters and form of skull base foramen ovale measured by three-dimensional spiral CT thin-slice scan in healthy adults

BACKGROUND： The accurate measurements of various data of the bone diameters of foramen ovale of living person can change the methods of puncturing trigeminal gasserian ganglion via foramen ovale for treating trifacial neuralgia from the experience of puncture operator only to puncture by taking the objective data of measurement as the evidence, which is good for improving the accuracy of puncturing trigeminal ganglion and reducing side effects. OBJECTIVE ： To observe the forms of foramen ovales in healthy adults displayed by volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan of skull base, and measure the longitudinal diameter and transverse diameter. DESIGN ： A repetitive observation and measurement SETTINGS ： Department of Neurosurgery and Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine. PARTICIPANTS： Fifty healthy adults （100 sides）, who were examined with three-dimensional spiral CT scan, were randomly selected from the Department of Medical Imaging, Foshan Hospital of Traditional Chinese Medicine from January 2005 to January 2006, including 26 males and 24 females, aged 25-68 years with an average of 48 years old. They were all informed and agreed with the examination. METHODS ： The subjects were examined with the Philips 16-slice spiral CT-Mx 8000 IDT CT apparatus （Philips Company, Holland）, the scanning ranged from 2 cm below the canthomeatal line to the level of suprasellar cistem. The width of collimator was 0.75 mm, pitch was 0.663; tube current was 350 mA, voltage was 120 kV, resolution was 512×512 matrix; slice thickness of reconstruction was 1 mm, and interval was 0.5 mm. After the three-dimensional spiral CT thin-slice scan of skull base, the image post-processing techniques including volume rendering and multi-planar reconstruction were applied to observe the forms of foramen ovales, and measure the size, longitudinal diameter and transverse diameter of the foramen ovales. The figures of the foramen ovales were drawn with mouse along the boundary of bone porous margin and soft tissue. According to the indications, the diameters were measured with computer to observe the forms of foramen ovales. MAIN OUTCOME MEASURES ： The longitudinal diameter, transverse diameter and form of foramen ovales were observed. RESULTS： All the 50 healthy adults （100 sides） were involved in the analysis of results. （1） It was observed in the volume rendering images that foramen ovales had four forms of oval shape （77 sides）, kidney shape （12 sides）, round shape （7 sides）, ribbon shape （4 sides）. （2） The longitudinal diameters of left and right foramen ovales were （7.67±1.32） and （7.98±1.45） mm, and the transverse diameters were （4.04±0.83）, （4.09±1.07） mm; There was no obvious difference between left and right longitudinal diameters （t = 1.63, P = 0.11 ）, and left and right transverse diameters were close （t = 0.45, P= 0.65）. CONCLUSION ： The non-invasive techniques of volume rendering and multi-planar reconstruction after three-dimensional spiral CT thin-slice scan can clearly display the formand size of foramen ovale in healthy adults.

Three-dimensional Imaging of Multi-slice Spiral CT in Bronchial Artery Correlative Study on Blood Supply of Central Lung Cancer and Its Clinical Significance

Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention therapy. Methods: Eighteen patients with central lungcancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchialartery reconstruction was done at the console work-station. The space anatomical characters ofbronchial artery were observed through different rotations. Results: For 6 cases, thethree-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes(lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate ofbronchial arteries was the highest in pulmonary artery stricture and truncation groups, and thevessels' diameter became larger apparently. These characters demonstrated blood supply of this kindof central lung cancer come from bronchial artery. Volume rendering images were the best ones amongthree-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery canreveal the anatomical characters of bronchial artery and provide theoretical evidence on bloodsupply and intervention therapy of central lung cancer.

Research on CT characteristics reconstruction technology

The traditional computed tomography(CT)reconstruction methods are noisy,low resolution,poor contrast,and generally not suitable to detect the smaller flaws.Besides,the filter design is also difficult.The CT characteristics reconstruction technology was brought forward to improve in these aspects,which is defined to directly reconstruct the characteristics of the projection for the best requirements not the overall image quality.The two-dimension(2D)and three-dimension(3D)CT characteristics reconstruction algorithm were firstly introduced,then by detailed analysis,experimental results and comparsion of parameters calculated,its advantages in keeping better high-frequency feature,better noise immunity,short time-consuming and easier design are verified.

Multi-Schlieren CT Measurements of Supersonic Microjets from Circular and Square Micro Nozzles

Instantaneous three-dimensional (3D) density distributions of a shock-cell structure of perfectly and imperfectly expanded supersonic microjets escaping into an ambient space are measured. For the 3D observation of supersonic microjets, non-scanning 3D computerized tomography (CT) technique using a 20-directional quantitative schlieren optical system with flashlight source is employed for simultaneous schlieren photography. The 3D density distributions data of the microjets are obtained by 3D-CT reconstruction of the projection’s images using maximum likelihood-expectation maximization. Axisymmetric convergent-divergent (Laval) circular and square micro nozzles with operating nozzle pressure ratio 5.0, 4.5, 4.0, 3.67, and 3.5 have been studied. This study examines perfectly expanded, overexpanded, and underexpanded supersonic microjets issued from micro nozzles with fully expanded jet Mach numbers Mj ranging from 1.47 - 1.71, where the design Mach number is Md = 1.5. A complex phenomenon for free square microjets called axis switching is clearly observed with two types “upright” and “diagonal” of “cross-shaped”. The initial axis-switching is 45° within the first shock-cell range. In addition, from the symmetry and diagonal views of square microjets for the first shock-cells, two different patterns of shock waves are viewed. The shock-cell spacing and supersonic core length for all nozzle pressure ratios are investigated and reported.

COMPUTER-AIDED THREE-DIMENSIONAL RECONSTRUCTION AND MEASUREMENT OF BONY AND MEMBRANOUS LABYRINTH

We used three methods to reconstruct a same bony and membranous labyrinth by an image processing work station(IPWS). Three dimensional (3-D)models of the bony and membranous labyrinth were thus obtained.Different parts of the labyrinth were measured and the spatial relationship

Three-Dimensional Computerized Tomography-Assisted Identification of Necrotic Volume, Distribution, Shape and Prognosis of Collapse in ONFH

Objective: We constructed 3D-model of ONFH in computer according to three-dimensional computerized tomography (3D-CT) data. We determined the location and volume of necrosis to investigate its clinical efficacy. Method: Totally 92 hips (59 cases) with ONFH (44 males, 15 females) were included, with mean age of 37.5 years (range from 26 to 58). Totally 20 cases (35 hips) were induced by corticosteroid (CTSs), 31 (49 hips) induced by alcohol, 4 (4 hips) induced by trauma and 4 (4 hips) idiopathic. All the hips were categorized into stage ARCO II. Finally diagnosed by MRI, all hips were scanned by CT to acquire data in DICOM format. The images were imported into software to extract 3D-shape of femoral heads, necrotic foci, their volumes and distribution in each quadrant. Deviation of volumes between digital image and biopsy specimen was analyzed by SAS9.1 package. Correlativity between collapse and volume of necrosis under specific pathogeneses was also analyzed. Among the cases necessitating total hip arthroplasty (THA) due to advancing to ARCO III, we randomly selected 8 of them to perform 3D-CT scanning thrice prior to surgical operation. Total femoral heads harvested were torn asunder. Cubic capacity of femoral heads and necrotic foci were hereby measured and compared with those acquired from digital models. Result: Through the digital model, necrotic foci were found mainly locating within the super lateral portion of femoral head, coinciding with those observed in biopsy specimen. Average volumetric ratio of digitally acquired necrosis focus/femoral head in 58 collapsed hips was 36.8%. The ratio of the 34 hips without collapse was 17.3%. In collapsed femoral heads, the distribution of necrosis focus was 23.4% in quadrant 1 (q1), 23.6% in q2, 12.1% in q3, 14.4% in q4, 9.0% in q5, 11.8% in q6, 1.6% in q7 and 3.9% in q8. In femoral heads without collapse, the distribution was 34.2% in q1, 29.6% in q2, 11.8% in q3, 11.3% in q4, 6.0% in q5, 6.0% in q6, 0.5% in q7 and 0.4% in q8. As for the average cubic capacities of femoral heads and necrotic foci, those acquired from the digital model and biopsy specimen had no significant difference in matched-pairs test (t = -1.49, P = 0.179 for femoral heads and t = -1.52, P = 0.172 for necrotic foci). There was significant difference (F = 2.720, P = 0.035 P was respectively 0.0001 and 0.0005). Decision tree model showed that 94.6% (53/56) hips would progress into collapse if the volumetric ratio of necrotic tissue was over 23.48%. Otherwise, if distribution in q2 was over 45.13%, 83.3% (5/6) hips would progress into collapse. No collapse (0/30) would occur if the distribution of necrotic tissue in q2 was under 45.13%. Conclusion: Digital 3D-model reconstructed from CT scanning can precisely incarnate spatial orientation of necrotic foci in femoral head. Multinomial logistic regression and decision-making tree shows that volumetric ratio of necrotic tissues plays an important role in anticipating collapse of femoral head.

颈内动脉颅底段的CT测量及三维重建

目的经鼻内镜鼻咽切除术是目前鼻咽颅底病变微创手术的首选,但颈内动脉损伤是该手术的潜在危险。通过术前对患者CT资料进行多层面观测和图像三维重建,评估颈内动脉的走行及其与相关结构的空间关系,以便指导鼻内镜鼻咽及咽旁隙颅底手术。方法选择40例(80侧)鼻咽及其周围颅底无病变表现的头部增强CT资料,在图像工作站上对不同层面中颈内动脉与周围骨性结构的关系进行测量,对图像进行三维重建观察颈内动脉与周围结构的空间关系。结果在骨性下鼻甲层面中,骨性下鼻甲后缘、翼内板后缘、翼外板后缘、中线与颈内动脉的距离分别为(38.8±4.0)、(25.9±2.8)、(19.7±3.8)、(23.8±2.7)mm;骨性下鼻甲后缘及翼内板后缘的延长线与颈内动脉的夹角为(15.0±4.0)、(17.0±6.0)°。在后鼻孔下缘层面中,翼内板后缘与颈内动脉的距离和角度分别为(27.2±3.5)mm和(12.0±4.0)°。三维重建获得清晰的立体图像。颈内动脉颈段的走行40%发生变异,其中大部分为弯曲型,位于口咽至咽隐窝水平,突向咽后壁。结论患者术前进行个体化CT三维重建能为经鼻内镜鼻咽颅底手术提供关键解剖信息,便于术中定位颈内动脉,提高手术安全性。人群中颈内动脉变异率较高,突向咽后壁,经鼻内镜鼻咽-咽旁颅底手术风险增高,术前应充分评估。

采用锥形束CT测量牙体长度的准确性研究

目的探索锥形束CT（CBCT）对牙体长度各参数测量的可行性及准确性。方法通过InVivoDental软件对40例患者109颗活体牙的CBCT扫描数据进行组织分割以及重建，得到目标牙长轴的颊舌向断层图像，测量根长、冠长和牙体全长。相同活体牙经外科拔除后，进行相应参数测量。比较实体测量值和CBCT测量值的差异，检验CBCT测量牙体长度的精确性。结果实验牙根长、冠长及牙体全长的CBCT测量值与实体测量值的差异无统计学意义（P值分别为0．790、0．621、0．657），两种测量方法差值的95％可信区间分别为（-1．10～1．13）、（-1．00～0．96）、（-1．00～1．05）mm。结论CBCT对活体牙的根长、冠长及牙体全长的无创测量与实体测量的一致性较好，可在临床推广应用。

基于螺旋CT影像的计算机辅助重建及测量上颌窦的实验研究

目的:建立一种基于螺旋CT影像的计算机辅助重建及测量上颌窦的方法,为上颌窦辅助诊断、手术治疗提供参考。方法:利用64排螺旋CT对60例正常成人(男30例,女30例)颌骨进行薄层容积扫描,将DICOM数据输入计算机辅助软件Simplant,重建上颌窦,测量相关数据并进行统计学分析。结果:上颌窦前后径均值为(35.12±3.47)mm,上下径均值为(39.58±2.96)mm,左右径均值为(32.14±2.50)mm,上颌窦容积均值为(15187.16±596.12)mm3。左右侧上颌窦径线值和容积无显著差异。男女性上颌窦径线值和容积无显著性差异。结论:利用该方法获得的上颌窦重建影像和测量数据可以为上颌窦影像诊断和手术治疗提供参考。

汉族人下颌角相关的三维CT与大体测量的比较研究

目的通过对汉族成年男女颅颌面软组织及螺旋CT三维重建骨性数据测量,并与颅骨测量数据对比分析,研究对颌面部诊断、治疗的影响因素。同时,也为下一步诊断模型的建立、调试奠定基础。方法随机选取汉族成年男女各20例(无颅骨明显畸形),进行颅颌面软组织测量及螺旋CT三维骨性测量,并行统计学分析。结果颌面部软组织对汉族男女性别特征的判断影响很大。在大体测量中,男女的头长、头宽、面中宽及表示下面部特征等多个数据的差异明显,三维CT与颅骨骨性测量的结果基本一致。结论三维螺旋CT与颅骨测量有良好的一致性;颌面部软组织对汉族人的性别判断、颌面诊疗影响很大。在治疗下面部畸形过程中,不仅需要对骨性的处理,还需要对软组织进行处理。这一点对女性患者尤为重要。

国人成人经第1及第2骶椎骶髂骨螺钉置钉钉道差异的CT测量

目的对国人经第1第2骶椎骶髂(sacral alar-iliac,SAI)螺钉固定钉道各参数进行CT测量,比较S1AI和S2AI螺钉钉道解剖参数差异。方法随机选取2015年4-10月本院影像归档和通信系统中60例骨骼发育成熟且骨盆正常国人的三维计算机断层扫描(3DCT)重建数据进行分析。S1和S2骶髂骨螺钉钉道参数中最大长度和宽度的轨迹通过旋转并截取三维骨盆获得。对长度和角度参数进行评估和比较。结果 S1AI置钉较S2AI置钉尾向倾角大,男性平均增加约26°,女性平均增加约24°[男性S1(57.25±4.37)°vs S2(31.02±7.43)°,女性S1(58.61±5.11)°vs S2(34.16±6.02)°;P<0.05];外倾稍小,男性、女性皆平均减少2°[男性S1(38.14±3.10)°vs S2(40.25±2.84)°,女性S1(37.24±2.96°)vs S2(39.25±2.64°);P<0.05];最长钉道长度:男性S1(119.46±3.77)mm vs S2(120.04±6.52)mm(P=0.551),女性S1(108.21±5.24)mm vs S2(109.47±4.63)mm(P=0.434);骶骨内钉道长度:男性S1(43.12±4.63)mm vs S2(35.75±5.03)mm(P<0.05),女性S1(39.73±5.85)mm vs S2(32.16±5.28)mm(P<0.05);髂骨内宽度:男性S1(22.05±4.91)mm vs S2(21.49±3.22)mm(P=0.672),女性S1(16.93±2.12)mm vs S2(15.35±2.71)mm(P=0.366);骨皮质距离:男性S1(9.42±2.41)mm vs S2(9.01±2.33)mm(P=0.352),女性S1(5.92±1.48)mm vs S2(6.34±1.26)mm(P=0.837)。S1AI与S2AI的入钉点比较,距皮肤距离、距中线距离、距髂后上棘距离均有统计学差异。结论国人成人骨盆存在最佳骶髂骨螺钉置钉钉道时,S1AI及S2AI螺钉均具有可行性。S1AI螺钉较S2AI螺钉置钉角度尾向倾角男性平均增加约26°,女性平均增加约24°,外倾稍小,男性女性皆平均减少2°,最长置钉长度基本相同,S1AI的入钉点距皮肤和髂后上棘更深,距中线稍远。临床操作中应注意S1和S2骶髂骨螺钉置钉角度、钉道长度及入钉点的差异。

术前X线、CT三维及二维影像重建对桡骨远端不稳定性骨折的评估意义

目的对比研究桡骨远端不稳定性骨折术前X线、CT三维及二维影像重建骨折的评估的异同及其对诊断、治疗意义。方法收集骨科自2013年5月至2016年2月桡骨远端不稳定性粉碎骨折病例资料29例,整理患者术前一般情况资料,术前数字X线正、侧位片,术前螺旋CT扫描并矢状位、冠状位二维及三维重建图像。根据X线、CT重建检查结果,分别确定桡骨远端不稳定性骨折的AO分型、关节面内骨折块数目、是否有关节面背侧骨折及骨折块的厚度、分离移位距离等指标。结果 X线AO分型A型10例,B型2例,C型c1为5例,c2为5例,c3为7例;CT分型A型1例,B型1例,C型c1为1例,c2为3例,c3为23例。RxC卡方检验McNemar-Bowker法,卡方值=20.0,P=0.001,有显著性统计学差异。X线检查及CT三维重建,对比术前桡骨远端关节内粉碎骨折块的数目(t=-13.09,P=0.001)、骨折块的分离移位距离(t=-2.326,P=0.031),经配对比较t检验,均有统计学显著性差异。结论术前数字X线及CT三维、二维重建评估关节内骨折,各有特点。CT重建,对于明确关节内骨折信息更精准,可靠,更具有指导意义。

CT三维重建青少年胸椎椎弓根断面测量的解剖学研究

目的为青少年胸椎椎弓根内固定术提供解剖学数据。方法多排螺旋CT对正常青少年(14～17岁)46例自愿者进行胸椎扫描,三维重建后,测量椎弓根高、椎弓根宽、椎弓根骨松质宽及椎弓根骨松质高,观察椎弓根内部骨质分布情况。结果椎弓根宽呈两端大、中段小的变化趋势,T4最小(3.85±0.77)mm,T1最大(8.12±1.39)mm;椎弓根高为逐渐增加的波浪形曲线,T3小峰:(10.93±0.88)mm,T12最大:(15.68±1.25)mm;椎弓根骨松质宽为先减小后增大,T11最大(5.24±1.3)mm;椎弓根骨松质高T4最小(5.74±2.4)mm,T11最大(13.18±2.3)mm。结论青少年胸椎真正能决定螺钉直径的是骨松质宽,椎弓根螺钉置入时应结合影像学资料,选择合适的螺钉及进钉部位和方向。

锥形束CT对下颌前磨牙髓腔三维重建的精度分析

目的:评价锥形束CT(cone-beam CT,CBCT)对下颌前磨牙髓腔三维重建的精度。方法:选取32颗单根下颌前磨牙,分别采用显微CT(micro-CT)和CBCT进行扫描,对髓腔进行三维重建,分别提取髓腔的三维表面模型和三维体积模型。在Amira5.0软件中对髓腔表面模型配准后,以micro-CT重建的髓腔模型为参考,检测CBCT重建模型和其相比的形态差异,进行色阶图颜色标示,记录整体形态的三维偏差值并分析2种扫描图像对髓腔体积重建的测量值差异。采用SPSS13.0软件包对数据进行统计学分析。结果:32颗牙的三维形态偏差RSM值平均为0.27mm,最大的形态差异分布于髓腔的根尖段和一些细小的解剖变异结构。Micro-CT和CBCT重建髓腔模型的体积测量值分别为(34.89±4.36)mm^3和(27.32±4.83)mm^3,差异具有显著性(P<0.05)。结论:利用CBCT扫描图像对下颌前磨牙髓腔进行三维重建时,存在着一定程度的结构丢失,且多位于根尖段和细小的解剖变异部位。口腔临床医师在利用CBCT辅助诊疗时,应考虑到以上特点。

X线曲面体层摄影、螺旋CT用于牙槽骨测量的比较

目的 :比较曲面体层摄影 (OP)、螺旋CT (SCT)与实体牙槽骨测量的差异 ,为牙种植手术提供客观依据。方法 :将3副颅骨标本各在12个部位用铝管、直径6mm钢球标志 ,拍摄SCT、OP,测量颌骨高度和/或宽度 ,再将颌骨依冠状面锯开后测量实际高度、宽度。SCT三维重建 ,比较差异。结果 :OP、SCT均有影象失真 ,放大率OP>SCT,分别为22.39%、5.28% ,OP、SCT、实测值间有极显著差异 ,P<0.0001。OP钢球与牙槽骨放大率经Wilcoxon检验无显著差异 ,P>0.5,相关系数r=0.8335,显示良好的正相关。结论 :对于牙种植手术前的牙槽骨测量不宜直接以OP或以OP机固有放大率校正的牙槽骨数值作为手术参考。用参照物放大率校正OP值有实用价值 ,能较好计算该部位牙槽骨实际高度。

多平面辅助定位法提高颅颌面三维CT测量准确性的研究

目的:建立一种较准确的三维头影测量定点方法,为面部不对称畸形的临床三维测量打下基础。方法:采用螺旋CT系统,对10例面部不对称畸形患者进行全头颅扫描,并进行CT影像三维重建,描绘测量16个相关解剖标志点。采用SAS8.02软件进行直线相关性和零截距直线回归分析,得到各标志点三维坐标的直线相关系数和零截距直线回归系数。结果:16个标志点的48个三维坐标数据的直线相关系数r、零截距直线回归系数b都在0.99000～1.01000以内。结论:本研究采用的三维测量方法具有较高的准确性和可重复性。该套定位要求及标志点,可以为面部不对称患者的硬组织形态特征改变研究提供参考。