基于CBCT观察上颌阻生尖牙患者蝶鞍形态变异情况

目的 利用锥形束CT(cone-beam computed tomography,CBCT)探讨上颌尖牙阻生与蝶鞍形态变异的相关性,从三维方向上评价蝶鞍变异对上颌尖牙阻生的临床预判。方法 收集125例上颌阻生尖牙患者(研究组)和125例与之相匹配的尖牙正常萌出者(对照组)。将所有样本CBCT数据导入Dolphin软件,进行重建头颅侧位片和三维图像,记录观察各组蝶鞍桥接(Ⅰ、Ⅱ、Ⅲ型)的类型分布和发生情况。使用SPSS 25.0软件对各组结果进行统计学分析。结果 研究组蝶鞍桥接的发生率显著高于对照组(P=0.004),PIC(腭侧尖牙阻生)组蝶鞍桥接的发生率显著高于对照组(P=0.007),Ⅱ型和Ⅲ型蝶鞍桥接分布和对照组存在统计学差异(P=0.012)。而BIC(唇侧尖牙阻生)组和对照组蝶鞍桥接的发生情况无统计学差异。三维重建图像上各组间蝶鞍桥接发生率无统计学差异(P>0.05)。结论 上颌尖牙阻生与蝶鞍桥接的发生情况有相关性,但仅上颌尖牙腭侧阻生患者更易发生蝶鞍桥接,而上颌尖牙唇侧阻生患者蝶鞍桥接的发生情况无变化。

基于CBCT中牙髓和牙体体积的机器学习用于青少年儿童年龄推断

目的利用锥形束计算机体层成像(cone beam computed tomography,CBCT)影像中左上颌中切牙与左上颌尖牙的牙髓体积和牙体体积,采用逐步回归法和机器学习方法分别推断青少年儿童年龄,并对推断效果进行比较分析。方法收集498例上海市汉族青少年儿童口腔颌面CBCT影像,测量左上颌中切牙与尖牙的牙髓体积和牙体体积并加以运算,运用K-最近邻、岭回归和决策树3种机器学习算法以及逐步回归法建立4个年龄推断模型,计算并比较决定系数、平均误差、均方根误差、均方误差和平均绝对误差等指标。绘制相关性热图,对参数间的单调关系进行可视化分析。结果K-最近邻模型(R^(2)=0.779)和岭回归模型(R^(2)=0.729)相对于逐步回归法(R^(2)=0.617)表现更为优越,而决策树模型(R^(2)=0.494)的拟合效果较差。相关性热图显示,年龄和牙髓体积、牙髓与牙体硬组织的体积比以及牙髓与牙体的体积比之间呈单调负相关。结论牙髓体积及牙髓体积占比与年龄之间存在密切关系,采用基于CBCT的机器学习方法能够提供更为准确的年龄推断结果,为进一步开展基于CBCT的深度学习牙龄推断研究奠定基础。

Knowledge and Practices of Dentists, Oral and Maxillofacial Surgeons of Cone Beam Computed Tomography (CBCT) and the Dentascanner in a Low Income Country: Case of Togo

Background: In dental-maxillofacial imaging, 3D sectional imaging progressively replaces conventional 2D imaging in developed countries. They are based specially on Computed tomography (CT-Scan), with the Dentascan application and cone beam computed tomography (CBCT). In developing countries those technics are newly introduced. Aim: This study aimed at studying the knowledge and practices of dentist and oral and maxillofacial surgeons on sectional imaging such as Dentascan and Cone Beam Computed Tomography (CBCT). Materials and Methods: We conducted an anonymous survey among dentists and oral maxillofacial surgeons in Togo over one month. Results: The response rate was 78.79% (27/33). They were mainly male sex (sex ratio of 2.25 men for one woman). They were aged between 27 and 71 years old with an average of 49.69 years old. The majority (61.54%) had a professional experience over 20 years. The majority of respondents (65.38%) believed their level of knowledge about dental x-Ray was poor. Half of them (50%) confirmed that they had never asked for a Dentascan, and 15.38% asked from time to time for it and only two (7.69%) asked often for this test. 96.15% confirm they have no knowledge of the Dentascan. Regarding the CBCT, 84.62% didn’t ask for it because this technique did not exist in Togo before. 69.20% of respondents confessed to be interested in continuing training on sectional imaging. Conclusion: This study shows that sectional imaging is very little used by oral and dental practitioners in Togo because of the ignorance of the new techniques and the absence of the CBCT. It is therefore necessary to promote the teaching of the new technique of sectional imaging in the training syllabus of oral and dental specialists and to initiate continuing medical training.

Comparison of bone alignment and fiducial marker alignment for online cone-beam computed tomography-guided radiation therapy for prostate cancer

Objective The aim of the study was to evaluate the coverage of the prostate when prostatic implanted fiducial markers are used to verify setup of the patients in comparison to the pelvic bones while using conebeam computed tomography(CBCT). Methods Seventeen patients with prostate cancer were included. For each patient, daily online CBCT was done. CT planning was matched with CBCT with the help of fiducial markers(3–5 markers) and another matching with done the help of pelvic bony landmarks. Registration of clinical target volume(CTV) 1 including prostate plus seminal vesicles and CTV2 including prostate only was done and were used to confirm the target volume during the process of matching. Delineation of the rectum on every CBCT was done. Two automatic margin representing planning target volume(PTV) were created. PTV1 was generated by adding 1 cm in all directions(PTV1a) and 0.7 cm in the posterior direction(PTV1b). PTV2 was generated by adding 0.5 cm in all directions(PTV2a) and 0.3 cm in the posterior direction(PTV2b). PTV1a was prescribed to receive 46 Gy in conventional fractionation with a boost dose of 30 Gy to PTV1b. The same dose was prescribed to PTV2a and PTV2b. Calculation of the percentage of intersection between CTV1and CTV2 created on CBCT with the original CTV scan was done. A comparison between the two CTVs(CTV1and CTV2) mean dose and the original delineated CTV was done. Then a comparison to the mean dose of the original CTV of PTV1a, PTV2a(CTV1a and CTV2a), and for PTV1b and PTV2b(CTV1b and CTV2b). Calculation of the mean rectal dose and also V60, V70 and V74 was done on the delineated rectum on every CBCT, and then a comparison to the planned original rectal dose. Results The created CTV1and CTV2 intersection percentage with the original CTV1and CTV2 significantly increased by 85%(range, 65%–95%, P < 0.05), when fiducial markers were used. The main difference of the received mean dose was significantly less in comparison to pelvic bone alignment(0.03% to 2% vs 0.03% to 11.6% for PTV1a, P < 0.006;0.01% to 1.8% vs 0.03% to 10.2% for PTV2a, P < 0.014;0.08 to 2.11 vs 0.04 to 11.29 for PTV1b, P < 0.015 and 0.01 to 1.79 vs 0.01 to 9.69 for PTV2b, P < 0.004). With the use of less PTV margins, significant decrease of the rectal mean dose, V60, V70 and V74 by P < 0.004, P < 0.004, P < 0.0005 and P < 0.009, respectively. Reduction of the CTV1a and CTV1b mean dose by 1.13% and 0.28% in comparison to the initial CTV1a and CTV2a.Conclusion A significant improvement of prostatic cancer patients alignment when fiducial markers are used, with more homogenous dose distribution, and with significant decrease in PTV margins. The delivered rectal dose is significantly less allowing prostate dose escalation.

A Pilot Survey of Odontomas for Size Constancy Using Cone-Beam Computed Tomography: Effect of Age, Sex, Lesion Location, and Histological Type: A Case Series

Objectives: Odontoma is the most common type of odontogenic tumors. Many studies have analyzed the statistical associations between odontoma location and patient age and sex, according to the histological tumor type. However, few studies have assessed odontoma morphological characteristics using cone-beam computed tomography (CBCT). We aimed to evaluate the association between odontoma location and size. Methods: We performed CBCT on patients with odontomas (19 patients;10 women, 9 men;average age, 12.6 [range, 6 - 34] years) according to the pathology type at a university hospital between April 2008 and February 2017. The locations of the lesions were noted, and their sizes were measured on CBCT images. Buccolingual, mesiodistal, and vertical diameters of the lesions were recorded on the same slice with the greatest diameters on axial, coronal, and sagittal CBCT images. Results: Altogether, 9 (47.4%) and 10 (52.6%) odontomas were located in the mandible and maxilla, respectively. There was no significant difference in the mesiodistal and vertical diameters on the CBCT image between the mandibular and maxillary groups when the odontoma size was compared with location (p < 0.05). However, the average diameters in only the buccolingual diameter were significantly greater in the maxilla. There were no significant differences between the two groups according to sex, age, or histological type. Conclusions: These data suggest that the sizes of odontomas in the maxilla are affected by bone expansion in the buccolingual direction, but they may be invariable in most settings. Three-dimensional assessment across the age groups suggests a lack of variation in size.

Application of cone beam computed tomography in facial imaging science

Facial imaging is used to study the facial shapeand its developmental changes over time.This isimportant to diagnose acquired malformations,to studynormal and abnormal growth and to differentiatebetween the results of treatment and normal growth,and to validate facial recognition.The two mainmethods to study and record facial imaging are bymeans of cephalometry and anthropometry[1].Cephalometrics is the scientific study of themeasurements of the

汉族人上颌第一前磨牙髓腔形态及增龄性改变的CBCT研究

目的应用CBCT研究汉族人上颌第一前磨牙髓腔形态与增龄性变化,为精准的临床治疗提供参考依据。方法收集汉族人上颌第一前磨牙360例(男、女各180例),年龄15~74岁,每十年为一组分为6组,分别测量颊侧髓角高度、舌侧髓角高度、颊舌侧髓角间距及根管口间距,并进行统计学分析。结果男性:颊侧髓角高度为(3.10±0.96)mm,舌侧髓角高度为(1.56±0.77)mm,颊舌侧髓角间距为(3.18±0.48)mm,颊舌侧根管口间距为(4.04±0.64)mm。女性:颊侧髓角高度为(3.04±0.79)mm,舌侧髓角高度为(1.67±0.73)mm,颊舌侧髓角间距为(3.11±0.42)mm,颊舌侧根管口间距为(3.88±0.53)mm。颊侧髓角高度与舌侧髓角高度间的差异均存在统计学意义(P<0.05)。不同年龄组间两两比较显示,均有显著统计学差异(P<0.05)。结论汉族人上颌第一前磨牙颊侧髓角高于舌侧髓角;颊舌侧髓角间距约为3mm;髓腔形态具有增龄性改变;随着年龄增长,颊、舌侧髓角高度显现性别差异。

Dosimetric consequences of tumor volume changes after kilovoltage cone-beam computed tomography for non-operative lung cancer during adaptive intensity-modulated radiotherapy or fractionated stereotactic radiotherapy

Objective The aim of this study was to investigate tumor volume changes with kilovoltage cone-beam computed tomography(k V-CBCT) and their dosimetric consequences for non-operative lung cancer during intensity-modulated radiotherapy(IMRT) or fractionated stereotactic radiotherapy.Methods Eighteen patients with non-operative lung cancer who received IMRT consisting of 1.8–2.2 Gy/fraction and five fractions per week or stereotactic radiotherapy with 5–8 Gy/fraction and three fractions a week were studied. k V-CBCT was performed once per week during IMRT and at every fraction during stereotactic radiotherapy. The gross tumor volume(GTV) was contoured on the k V-CBCT images,and adaptive treatment plans were created using merged k V-CBCT and primary planning computed tomography image sets. Tumor volume changes and dosimetric parameters,including the minimum dose to 95%(D95) or 1%(D1) of the planning target volume(PTV),mean lung dose(MLD),and volume of lung tissue that received more than 5(V5),10(V10),20(V20),and 30(V30) Gy were retrospectively analyzed.Results The average maximum change in GTV observed during IMRT or fractionated stereotactic radiotherapy was –25.85%(range,–13.09% ––56.76%). The D95 and D1 of PTV for the adaptive treatment plans in all patients were not significantly different from those for the initial or former adaptive treatment plans. In patients with tumor volume changes of >20% in the third or fourth week of treatment during IMRT,adaptive treatment plans offered clinically meaningful decreases in MLD and V5,V10,V20,and V30; however,in patients with tumor volume changes of < 20% in the third or fourth week of treatment as well as in patients with stereotactic radiotherapy,there were no significant or clinically meaningful decreases in the dosimetric parameters.Conclusion Adaptive treatment planning for decreasing tumor volume during IMRT may be beneficial for patients who experience tumor volume changes of >20% in the third or fourth week of treatment.

不同矢状骨面型患者后牙颊舌向倾斜度及Wilson曲线曲度的CBCT测量研究

目的 研究不同矢状骨面型患者的后牙颊舌向倾斜度及Wilson曲线曲度,探讨不同矢状骨面型患者的后牙水平向倾斜代偿机制,为骨性错畸形治疗中后牙倾斜度控制提供参考依据。方法 本研究已通过单位伦理委员会审查批准,并获得患者知情同意。选取90例青少年及90例成人正畸治疗前的CBCT资料作为研究对象,两组样本中各包括矢状骨面型Ⅰ类、Ⅱ类、Ⅲ类各30例。分别测量每一侧由第一前磨牙至第二磨牙的所有后牙颊舌向倾斜度、第一磨牙及第二磨牙的Wilson曲线曲度,比较不同矢状骨面型的青少年及成人间的差异。结果 与Ⅰ类骨面型成人相比,Ⅱ类骨面型成人的上颌后牙倾斜度减小,下颌后牙倾斜度增大,差异有统计学意义;Ⅲ类骨面型成人上颌后牙倾斜度增大,下颌后牙倾斜度减小,差异有统计学意义;Ⅱ类骨面型成人第二磨牙的Wilson曲线曲度显著性增大,差异有统计学意义。与Ⅰ类骨面型青少年相比,Ⅲ类骨面型青少年的上颌后牙倾斜度增大,差异有统计学意义。不同矢状骨面型青少年下颌后牙倾斜度差异无统计学意义。对比青少年与成人,Ⅱ类骨面型成人上后牙更偏舌倾,除下颌第一磨牙外下颌后牙更偏直立;Ⅲ类骨面型成人下颌后牙除下颌第二磨牙外更偏舌倾,差异有统计学意义,上颌后牙无明显变化,差异无统计学意义。结论 上下后牙的颊舌向倾斜度及Wilson曲线曲度在不同矢状骨面型人群间存在差异,Ⅱ类骨面型人群以上后牙代偿性舌倾、下后牙代偿性直立为主。Ⅲ类骨面型人群以下后牙代偿性舌倾为主,上后牙维持原有的代偿性颊倾。

成人骨性Ⅲ类错牙合伴下颌偏斜患者下颌骨三维对称性的CBCT观察分析

目的:研究成人骨性Ⅲ类错伴下颌偏斜患者下颌骨的三维特征。方法:纳入正畸成人骨性Ⅲ类错患者62名,按照颏点的偏离程度分为颜面部不对称组30例和颜面部对称组32例,用锥形束CT(cone-beam computed tomography,CBCT)三维扫描获得颅面部DICOM数据,采用Dolphin 11.0对下颌骨进行三维重建,选择描述下颌骨骨性结构特征的13个点进行描记,对下颌骨37个变量进行分析统计。结果:颜面部不对称组偏斜侧髁突及下颌角点相对于偏斜对侧处于向后、向外、向上的位置,偏斜对侧有着更长的下颌体、下颌支、髁突和更大的下颌支倾斜度及髁突倾斜度。结论:髁突、下颌支、下颌体的不对称生长发育及下颌骨的旋转都是导致下颌偏斜的因素。

CBCT与螺旋CT对颞颌关节成像的比较

目的:通过锥体束CT(CBCT)与螺旋CT对颞颌关节成像的比较,探讨CBCT影像与螺旋CT对颞下颌关节成像大体解剖结构的一致性;通过比较分析研究CBCT在颞下颌关节检查成像中的临床诊断意义。方法:对1名成人通过严格的TMJ临床检查为健康关节志愿者在同一时间行CBCT与螺旋CT扫描,并进行分析。结果:CBCT与螺旋CT二者重建的解剖形态影像基本一致。受检者的影像均可较清晰再现颞下颌关节结构形态及相对位置关系。结论:比较证实CBCT能准确反映颞下颌关节解剖形态,具有广泛的临床应用前景。

54例正常人双侧颞下颌关节CBCT测量值分析

目的:探讨应用CBCT(cone-beam computed tomography)对成年人两侧颞下颌关节进行多项指标数据测量分析。方法:在TMJ成像与测量技术的基础上,筛选出正常成人54例,通过严格的TMJ临床检查确定为健康关节,利用Newtom 9000 CBCT对其ICP位颞下颌关节进行成像后测量分析。结果:在轴位测得髁状突水平角以及单侧髁状突距矢状中线的距离;平行于髁状突长轴的斜位,测髁状突长轴径,垂直角度,沿髁状突长轴顶内外极间任意角间隙宽度;垂直于髁状突长轴的斜位测量关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度;矢状位测关节髁状突前中后任意角间隙宽度,关节凹深度和前斜面角度关节颈厚度。结论:正常成人双侧髁状突位置及关节窝形态性别差异不明显,双髁状突位置及关节窝形态基本对称。

CBCT在诊治埋伏阻生牙中的应用

目的:探讨CBCT在埋伏阻生牙诊治中的应用。方法:对56例(37颗多生牙、41颗阻生牙)经全景片检查需进一步明确诊断的埋伏阻生牙,进行CBCT扫描,通过三维重建、矢状位、冠状位及轴位断层进行分析。结果:与全景片比较,CBCT能准确定位埋伏阻生牙的位置、生长方向、数量,准确率差异有统计学意义(P<0.05)。结论:CBCT可以更直观、准确地对埋伏阻生牙定位,特别是在上颌前牙区的临床诊治更有应用价值。

CBCT在牙齿纵裂中的临床诊断价值评价

目的:比较CBCT与X线根尖片在诊断牙齿纵裂准确度中的差异性,评价CBCT在牙齿纵裂中的临床诊断价值。方法:在病人知情同意下选取临床上怀疑有牙根纵裂的病人40例(40个牙),均拍摄X线根尖片并进行CBCT扫描。分别由2位专家采用单盲法对CBCT、根尖片影像进行诊断,比较两种影像学方法诊断牙齿纵裂中的真实性。结果:CBCT扫描诊断牙齿纵裂的敏感性Sen、粗符合率CA、约登指数γ、阴性预测值PV-分别为97.37%、97.50%、97.37%、66.67%,而X线根尖片则为73.68%、72.50%、23.68%、9.09%,在诊断牙齿纵裂方面,CBCT扫描与X线根尖片相比有更高的敏感性和准确度,差别具有统计学意义(P<0.05)。结论:与X线根尖片相比CBCT扫描对牙齿纵裂的诊断具有更高的准确度,有重要的临床应用价值。

上颌四眼圈簧扩弓后对上颌牙齿及上颌骨变化影响的CBCT研究

目的:使用锥体束CT(CBCT)评估上颌四眼簧慢速扩弓后上颌牙齿及上颌骨宽度的变化。方法:选择13例需要综合性正畸治疗的患者(男5例,女8例),平均年龄(14.4±2.2)岁,使用上颌四眼圈簧扩弓。对患者扩弓前(T1)后(T2)的变化进行CBCT扫描,测量扩弓前后两侧尖牙、第一前磨牙、第二前磨牙和第一磨牙之间的牙冠和根尖之间的宽度,第一磨牙的倾斜度,基骨弓和腭中缝宽度的变化。应用SPSS 17.0软件对测量结果进行配对t检验。结果:四眼圈簧扩弓后牙弓变化明显。4对牙的牙间距分别增加了(2.47±1.05)mm、(2.97±1.90)mm、(2.79±1.21)mm、(3.15±1.15)mm,根尖距分别减小了(1.19±0.40)mm、(2.12±0.68)mm、(2.02±0.65)mm、(1.34±0.63)mm,左侧磨牙倾斜度减小了4.45°±2.86°,右侧磨牙倾斜度减小了4.02°±1.45°,基骨弓宽度增加了(2.37±0.96)mm,腭中缝宽度增加了(1.21±0.50)mm,差异均具有统计学意义(P<0.001)。结论:四眼圈簧扩弓器对上颌牙弓的扩弓主要通过牙齿倾斜移动完成,而非整体移动。

功能矫治器前导下颌后颞下颌关节变化的影像学研究进展

以下颌后缩为主要特征的骨性Ⅱ类错牙合畸形在青少年中非常多见,临床多采用功能矫治器对此类正处于发育高峰期的青少年患者进行矫治。本文对近年来功能矫形治疗后颞下颌关节内髁突、关节窝、关节盘等成分变化的影像学研究,以及功能矫形对颞下颌关节的影响进行综述回顾。

汉族人群腭大孔解剖位置及其与腭穹隆形态关系的CBCT研究

目的:研究汉族青年人群腭大孔解剖位置及其与腭穹窿形态的关系。方法:采用CBCT测量209名18~45岁汉族受试者腭大孔的相对位置及毗邻关系,并讨论腭穹窿形态对腭大孔位置的影响。结果:腭大孔在第三磨牙近中、腭侧和远中的分布率分别是17.22%、64.59%和18.18%。男性与女性腭大孔至腭中缝(GPF-MMS)的距离分别为(16.29±1.47)mm和(15.60±1.35)mm,腭大孔至牙槽嵴顶(GPF-AC)的距离为(14.02±2.69)mm和(12.29±2.41)mm。GPF-MMS的距离在腭高耸组中明显低于腭低平组;相反,GPF-AC的距离在腭高耸组中明显高于腭低平组。结论:汉族青年人群腭大孔的位置与患者腭穹隆形态和性别有关。

继发性牙根纵裂诊断的研究进展

牙根纵裂是一种源自牙根的纵向裂纹,可发生在活髓牙和根管治疗后牙齿,是病因复杂、预后较差的牙体硬组织疾病。发生于牙髓治疗后的牙根纵裂称为继发性牙根纵裂(secondary vertical root fracture,SVRF),对SVRF的诊断,应结合临床体征(如疼痛、肿胀、牙齿松动、位于牙龈边缘附近的窦道和深而窄的孤立牙周袋)和根尖片(如牙周膜增宽、垂直骨丧失和根周骨丧失、根周“晕圈状”或“J”形的透射影)进行综合判断。对疑似牙根纵裂的牙齿,应通过锥形束CT(cone⁃beam computed tomography,CBCT)等三维影像学辅助诊断,如CBCT显示牙根上的折裂线以及颊侧或舌侧骨板缺损;优化设置CBCT参数,如选用小视野CBCT、增强染料辅助的应用、使用金属伪影还原工具(metal artifact reduction,MAR)等方法提高CBCT诊断SVRF的精确度。使用多种影像技术可对不同宽度的裂纹进行检测,如核磁共振成像(magnetic resonance imaging,MRI)中表现为异常的高强度信号;使用数字减影技术(digital subtraction radiography,DSR)进行图像处理后出现的黑色线状区域;不同宽度的裂纹在光学相干断层扫描(optical coherence tomography,OCT)可表现为高亮度线或暗区。人工智能(artificial intelligence,AI)诊断技术和预测模型也是SVRF诊断的辅助手段。通过各种无创手段仍然无法确诊的SVRF病例,可通过根管内直视和翻瓣手术中直视发现SVRF。

卷积神经网络在口腔疾病中应用的研究进展

卷积神经网络(CNN)在图像识别领域中表现较为突出,它作为一种人工智能的代表性方法,在口腔医学领域受到了广泛的关注。CNN在口腔疾病的预测、诊断及治疗等方面都有较高的能力,可帮助临床医师制定治疗计划。该文对CNN在口腔疾病中应用的研究进展作一综述。

基于CBCT的ORFIT固定架在前列腺癌调强放疗中的摆位误差

目的比较ORFIT全身泡沫体位固定架与负压真空气垫固定在前列腺癌调强放射治疗中的摆位误差。方法对22例前列腺癌患者采用ORFIT全身泡沫体位固定架进行调强放疗,另22例采用负压真空气垫固定进行调强放疗,分析比较ORFIT全身泡沫体位固定架与负压真空气垫固定的摆位误差。结果 ORFIT全身泡沫体位固定架组患者在LR、SI和AP方向及旋转角度的摆位误差,均明显小于负压真空气垫组(0.16±0.12 vs.0.23±0.11,t=-2.219,P=0.028;0.18±0.13 vs.0.19±0.12,t=-2.009,P=0.046;0.15±0.10 vs.0.25±0.12,t=-2.168,P=0.02;0.27±0.24 vs.0.38±0.31,t=-3.718,P=0.000);其中ORFIT全身泡沫体位固定架组患者在LR和SI方向上验证摆位误差小于±3 mm次数百分比与负压真空气垫组相似(87.88%vs.81.06%,χ2=2.33,P=0.13;89.39%vs.86.36%,χ2=0.87,P=0.35);但在AP方向上小于±3 mm次数百分比较负压真空气垫组明显增高(90.91%vs.78.03%,χ2=7.248,P=0.007)。结论对前列腺癌调强患者,ORFIT全身泡沫体位固定架技术较负压真空气垫固定可以更好减少摆位误差,特别是在AP方向上,提高放疗精确度,值得临床进一步研究应用。