重建算法及参数对SPECT颞颌关节显像髁突代谢活性的影响  

Condyle metabolic activity on SPECT of temporomandibular joint imaging with different reconstruction algorithms and parameters

作　　者：李文宇 沈美娟[1] 江凌龙[1] 徐超 文兵[1] 汪长银[1] LI Wenyu;SHEN Meijuan;JIANG Linglong;XU Chao;WEN Bing;WANG Changyin(Department of Nuclear Medicine,Zhongnan Hospital of Wuhan University,Wuhan 430071,China)

机构地区：[1]武汉大学中南医院核医学科,湖北武汉430071

出　　处：《中国医学影像技术》2022年第8期1243-1248,共6页Chinese Journal of Medical Imaging Technology

摘　　要：目的观察滤波反投影法(FBP)、二维有序子集最大期望值法(2D-OSEM)及其参数对SPECT颞颌关节显像髁突代谢活性的影响。方法回顾性分析197例因单侧髁突异常增生致偏颌畸形患者,分别以2D-OSEM及FBP算法对SPECT重建图像,前者子集数为2、4、8,迭代次数为4、8、16,后者应用巴特沃斯滤波器,设定截止频率为0.32,阶数为9。基于重建图像分别计算双侧髁突摄取百分率差值,评估髁突代谢活性;观察FBP和2D-OSEM算法子集数及迭代次数对双侧髁突摄取百分率差值及髁突代谢活性阳性率的影响。结果双侧髁突摄取百分率差值在子集数为2、迭代次数为4的2D-OSEM重建图像中[9.00%(4.20%,16.90%)]与FBP重建图像中的差异无统计学意义(Z=-1.86,P=0.06),而在其余2D-OSEM图像中均高于FBP图像(P均<0.01)。子集数(F=16.85,P<0.01)及迭代次数(F=34.29,P<0.01)对2D-OSEM重建图像中的双侧髁突摄取百分率差值存在显著主效应,且其间存在交互效应(F=13.14,P<0.01),双侧髁突摄取百分率差值随子集数或迭代次数增加而增高。2D-OSEM(142/197,72.08%)与FBP(88/197,44.67%)重建图像的髁突代谢活性总阳性率差异有统计学意义(χ^(2)=30.91,P<0.01)。2D-OSEM重建图像中,子集数为4时,髁突代谢活性阳性率的平均值为53.80%,与子集数为2(50.93%)及8时(57.87%)差异均无统计学意义(χ^(2)=0.98、1.98,P=0.32、0.16);子集数为8时,髁突代谢活性阳性率平均值高于子集数为2时(χ^(2)=5.74,P=0.02);迭代次数为8时,髁突代谢活性阳性率的平均值为53.81%,与迭代次数为4(51.10%)及16(57.70%)时差异均无统计学意义(χ^(2)=0.87、1.82,P=0.35、0.18);迭代次数为16时,髁突代谢活性阳性率的平均值高于迭代次数为4时(χ^(2)=5.19,P=0.02)。结论采用FBP或2D-OSEM算法及不同参数行SPECT颞颌关节显像重建,髁突代谢活性存在差异。Objective To observe the impact of reconstruction algorithms filtered-back projection(FBP)and twodimensional ordered subset expectation maximization(2D-OSEM)and relative parameters of condyle metabolic activity on SPECT temporomandibular joint imaging.Methods Data of 197patients with facial asymmetric deformity caused by unilateral condylar hyperplasia were retrospectively analyzed.SPECT data were reconstructed with 2D-OSEM and FBP,and the number of subset was 2,4and 8of 2D-OSEM,and the iteration number was 4,8and 16,respectively,whereas Butterworth filter was applied,the cutoff frequency was set as 0.32and the order was set as 9of FBP.The percentage differences of bilateral condylar uptake were calculated based on the reconstructed images,and the condyle metabolic activity was evaluated.The impact of FBP,the subsets and iterations of 2D-OSEM on the percentage differences of bilateral condyle uptake and the positive rate of condylar metabolic activity were observed.Results No significant difference of the percentage difference of bilateral condylar uptake between 2D-OSEM reconstructed images with subset number of 2and iteration of 4[9.00%(4.20%,16.90%)]and FBP reconstructed images(Z=-1.86,P=0.06),while the difference of the percentage of condylar uptake on other 2D-OSEM images were all higher than that on FBP images(all P<0.01).Both the number of subsets(F=16.85,P<0.01)and iterations(F=34.29,P<0.01)had significant main effect on the percentage difference of bilateral condylar uptake on 2D-OSEM,while there was an interaction effect between these two(F=13.14,P<0.01),the percentage difference of bilateral condylar uptake increased when the numbers of subset or iteration became larger.The total positive rate of condyle metabolic activity showed on 2D-OSEM(142/197,72.08%)and FBP(88/197,44.67%)images were statistically significant(χ^(2)=30.91,P<0.01).When the subset number of 2D-OSEM reconstruction was 4,the average positive rate of condyle metabolic activity was 53.81%,no significant different with that of subset num

关 键 词：颞颌关节 体层摄影术 发射型计算机 单光子 滤波反投影法 二维有序子集最大期望值法 

分 类 号：R782.6[医药卫生—口腔医学] R817.4[医药卫生—临床医学]