中华生物医学工程杂志
中華生物醫學工程雜誌
중화생물의학공정잡지
CHINESE JOURNAL OF BIOMEDICAL ENGINEERING
2014年
6期
446-450
,共5页
冯强%马智军%伍建林%于洪
馮彊%馬智軍%伍建林%于洪
풍강%마지군%오건림%우홍
图像处理,计算机辅助%肾脏%诊断显像%表观弥散系数%各向异性分数
圖像處理,計算機輔助%腎髒%診斷顯像%錶觀瀰散繫數%各嚮異性分數
도상처리,계산궤보조%신장%진단현상%표관미산계수%각향이성분수
Image processing,computer - assisted%Kidney%Diffusion tensor imaging%Diagnostic imaging%Fractional anisotropy
目的 探讨b值的选取对DTI测量指标和图像质量的影响,从而获得最佳b值.方法 随机招募20例健康志愿者行DTI成像,b值的选择为0、200、400、600、800、1 000 s/mm2,弥散梯度方向为6,分别测量ADC值、FA值,SNR、CNR,对ADC图进行评分,分析不同b值时的变化规律.结果 5组b值获得的肾实质、皮质、髓质的ADC值及SNR值比较具有统计学意义(F值为1846.65、368.93、207.80和951.93,P<0.05),随着b值的增大,ADC值变小,SNR值变小.不同b值的肾实质、皮质、髓质的FA值及CNR值比较均不具有统计学意义(F值为0.98、1.07、1.14和1.13,P>0.05).相同b值时皮、髓质ADC值和FA值比较均具有统计学意义(P<0.05).ADC图得分随着b值的增大,图像质量变差.b值取0、800 s/mm2时,ADC图的图像质量具有诊断意义,但皮髓质分辨不清晰.b值与肾实质ADC值、SNR上呈负相关(r=-0.980和-0.974,P<0.05),而与FA值、CNR无相关(r=-0.156和-0.152,P>0.05).结论 b值为600 s/mm2的图像质量较好,皮髓质差异容易分辨,适合于肾脏的研究.
目的 探討b值的選取對DTI測量指標和圖像質量的影響,從而穫得最佳b值.方法 隨機招募20例健康誌願者行DTI成像,b值的選擇為0、200、400、600、800、1 000 s/mm2,瀰散梯度方嚮為6,分彆測量ADC值、FA值,SNR、CNR,對ADC圖進行評分,分析不同b值時的變化規律.結果 5組b值穫得的腎實質、皮質、髓質的ADC值及SNR值比較具有統計學意義(F值為1846.65、368.93、207.80和951.93,P<0.05),隨著b值的增大,ADC值變小,SNR值變小.不同b值的腎實質、皮質、髓質的FA值及CNR值比較均不具有統計學意義(F值為0.98、1.07、1.14和1.13,P>0.05).相同b值時皮、髓質ADC值和FA值比較均具有統計學意義(P<0.05).ADC圖得分隨著b值的增大,圖像質量變差.b值取0、800 s/mm2時,ADC圖的圖像質量具有診斷意義,但皮髓質分辨不清晰.b值與腎實質ADC值、SNR上呈負相關(r=-0.980和-0.974,P<0.05),而與FA值、CNR無相關(r=-0.156和-0.152,P>0.05).結論 b值為600 s/mm2的圖像質量較好,皮髓質差異容易分辨,適閤于腎髒的研究.
목적 탐토b치적선취대DTI측량지표화도상질량적영향,종이획득최가b치.방법 수궤초모20례건강지원자행DTI성상,b치적선택위0、200、400、600、800、1 000 s/mm2,미산제도방향위6,분별측량ADC치、FA치,SNR、CNR,대ADC도진행평분,분석불동b치시적변화규률.결과 5조b치획득적신실질、피질、수질적ADC치급SNR치비교구유통계학의의(F치위1846.65、368.93、207.80화951.93,P<0.05),수착b치적증대,ADC치변소,SNR치변소.불동b치적신실질、피질、수질적FA치급CNR치비교균불구유통계학의의(F치위0.98、1.07、1.14화1.13,P>0.05).상동b치시피、수질ADC치화FA치비교균구유통계학의의(P<0.05).ADC도득분수착b치적증대,도상질량변차.b치취0、800 s/mm2시,ADC도적도상질량구유진단의의,단피수질분변불청석.b치여신실질ADC치、SNR상정부상관(r=-0.980화-0.974,P<0.05),이여FA치、CNR무상관(r=-0.156화-0.152,P>0.05).결론 b치위600 s/mm2적도상질량교호,피수질차이용역분변,괄합우신장적연구.
Objective To investigate how the selection of b-value intersects with the measures and image resolution of diffusion tensor imaging (DTI),in search for an optimal b-value.Methods Twenty randomly recruited healthy volunteers were examined by DTI with the b-values set to 0,200,400,600,800 and 1 000 s/mm2,and diffusion gradient directions set to 6.The values of apparent diffusion coefficient (ADC)and fractional anisotropy(FA),signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were measured,respectively,and the ADC images were scored and analyzed statistically.The variation in imaging measure along with different b-values was analyzed by Spearman rank correlation.Results There were statistical difference between ADC and SNR values in renal parenchyma,cortex and medulla obtained with five b-values(F-values were 1846.65,368.93,207.80 and 951.93 respectively,P<0.05).The ADC and SNR values decreased along with increasing b-values.No statistical difference was found between FA and CNR values in renal parenchyma,cortex and medulla with different b-values(F-values were 0.98,1.07,1.14 and 1.13 respectively,P>0.05).Given the same b-value,ADC and FA values differed between the renal cortex and medulla (P<0.05).The scores of ADC images increased with worsening image resolution along with the higher b-values.When b-value was 0 or 800 s/mm2,the resolution of ADC image might help clinical diagnosis but was with poor discrimination between the cortex and medulla.The b-value was negatively correlated with ADC value and SNR of renal parenchyma(r=-0.980 and-0.974,P<0.05),but not correlated with FA value and CNR(r=-0.156 and-0.152,P>0.05).Conclusions Image with a b-value of 600 s/mm2 may have good quality that easily distinguishes between cortex and medulla in favor of renal studies.
