Thevalueofmodel-basediterativereconstructioninoptimizingthyroidCTimaging
10.3969/j.issn.1002-1671.2019.04.030
- VernacularTitle:基于模型的迭代重建在优化甲状腺CT图像中的价值
- Author:
Yongjun JIA
1
;
Haifeng DUAN
;
Jing CHEN
;
Zhen YANG
;
Qian TIAN
;
Lihua FAN
;
An YUN
Author Information
1. 陕西中医药大学附属医院医学影像科
- Keywords:
computedtomography;
adaptivestatisticaliterativereconstruction;
model-basediterativereconstruction;
thyroid
- From:
Journal of Practical Radiology
2019;35(4):634-637,646
- CountryChina
- Language:Chinese
-
Abstract:
Objective Toexploretheroleofmodel-basediterativereconstruction (MBIR)algorithminimprovingthequalityof thyroidCTimagesbyreducinghardeningartifactsattheentrancetothethorax.Methods ChestCTscansof20patientswiththyroidnoduleswere retrospectivelyreviewed.AlgorithmsofFBP,ASIR40,MBIRSTNDandMBIRNR40 wereusedtoreconstructatthe0.625mmslicethickness.Region ofinterestwasplacedonthecoronalimageswiththemostobvioushardeningartifacts.ThestandarddeviationsoftheCTvaluesof theleftandrightthyroidarteriesandthesurroundingnormalthyroidtissueweremeasured,furthermore,thevalueofthyroidartifact index(AI)andAI=sqrt(SDa2-SDb2)werecalculated.Tworadiologistsused4-pointmethodtoassessimageartifactssubjectivly.(1 point,severeartifacts,unclearthyroidrimsandnodules,undiagnosed;2points,moderateartifacts,poorlydisplayingthyroid margins andinternaldetails,affectivediagnosis;3points,mildartifacts,showingthyroid marginandinternaldetails,noaffectingthediagnosis;4 points ,no ribbon artifacts ,displaying thyroid edge and internal details very w ell ).ANOVA and paired t-test w ere used to co m pare the CTvaluesofnormalthyroidtissueofleftandrightlobeamongdifferentreconstructedimagesofthyroid.Subjectivescoredifferenceswere testedusingthe W ilcoxon symbolscale.Results ThevalueofCTreductionandAIatFBPandASIR40reconstructionimagesweresignificantly greaterthanthoseatMBIRSTNDandMBIRNR40reconstructionimages. Whiletherewerenodifferenceofleftandrightlobeofthyroid CTreductionand AIvalueatFBPand ASIR40reconstruction imagesnorthoseatMBIRSTNDandMBIRNR40reconstructionimages. SubjectiveevaluationofclavicleartifactswasincreasedatMBIRSTND and MBIRNR40image,andMBIRNR40imagehadoptimalsubjectiveevaluationresults(P<0.05).Conclusion MBIRcansignificantlyreducethe impactoftheclavicularharnesshardeningartifactsandnoiseonthethyroidanditsnodulesduringCTscans,especiallyoptimizingthe low-densitycontrastsettingofMBIRNR40.
