本文選題：體素內(nèi)不相干運動　切入點：擴(kuò)散加權(quán)成像　出處：《廣州中醫(yī)藥大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：目的:評價心電門控(electrocardiograph-triggered)技術(shù)對肝臟體素內(nèi)不相干運動成像(magnetic resonance diffusion-weighted intravoxel incoherent motion imaging,IVIM-DWI)圖像質(zhì)量、表觀擴(kuò)散系數(shù)(apparent diffusion coefficient,ADC)及IVIM相關(guān)參數(shù)測量值大小及其可重復(fù)性的影響;同時在此基礎(chǔ)上研究基于心電門控的IVIM-DWI技術(shù)在臨床肝臟病變中的診斷價值。方法:實驗一:選擇2015年5月至2015年12月期間符合條件的116名接受心電門控IVIM-DWI 序列掃描的志愿者,設(shè)定 6 個 b 值(b=0,50,100,150,300,600s/mm2),按受檢者心率分為2組,低心率組受檢者心率≤70次/分,高心率組受檢者心率≥80次/分。采用單指數(shù)線性函數(shù)模型和雙指數(shù)非線性模型對掃描所得全肝IVIM-DWI圖像進(jìn)行擬合得到平均ADC圖,以及D值、D*值和f值偽彩參數(shù)圖。選取其中連續(xù)3層作為R0I放置層面,在所選層面肝左、右葉各放置3個100mm2的圓形R0I,共各取9個R0I的平均值代表左、右肝的ADC值、D值、D*值和f值,并進(jìn)行統(tǒng)計分析。實驗二:選擇2016年5月至2016年6月期間符合條件的18名中青年健康志愿者,每位志愿者行兩次腹部IVIM-DWI檢查,掃描過程中采用自由呼吸、自由呼吸結(jié)合心電門控兩種技術(shù)采集5層肝臟IVIM-DWI圖像,b值取0,50,100,150,300,600s/mm2。每個序列選擇中間三層圖像,分別在肝左、右葉實質(zhì)、腹壁外各放置3個100 mm2的圓形R0I進(jìn)行圖像分析,獲得相應(yīng)的肝臟信號強(qiáng)度(signal intensity,SI)、信號噪聲(standard deviation,SD),計算SNR值。同實驗一的方法獲取肝臟平均ADC值、D值、D*值和f值。兩次測量的一致性評價采用配對t檢驗、pearson相關(guān)系數(shù)及組內(nèi)相關(guān)系數(shù)ICC進(jìn)行分析。兩次掃描獲得的ADC、D、D*和f測量值的一致性采用Bland-Altman方法評價。對兩種技術(shù)中肝左、右葉平均SNR值、ADC值、D值、D*值和f值進(jìn)行統(tǒng)計分析。實驗三:收集2016年6月至2016年12月在我院診斷肝臟局灶性病變并行上腹部IVIM-DWI檢查的66例患者(共85個病灶),所有患者于治療前行常規(guī)上腹部MR掃描及IVIM-DWI掃描,掃描采用自由呼吸、自由呼吸結(jié)合心電門控兩種技術(shù),b值取0,50,100,150,300,600s/mm2。分別在肝左、右葉實質(zhì)、病灶、腹壁外各放置3個100 mm2的圓形R0I進(jìn)行圖像分析,計算SNR、CNR值。將R0I放置于病灶最大層面,獲得病灶平均ADC值、D值、D*值和f值。采用配對t檢驗比較自由呼吸和自由呼吸結(jié)合心電門控良惡性組間各b值的SNR、CNR及擬合所得ADC、D、D*、f值。結(jié)果:實驗一:(1)低心率組和高心率組所得肝左葉ADC值、D值、f值高于肝右葉,均具有顯著性差異(P0.05)。(2)低心率組肝左葉的平均ADC值、D值、f值均低于高心率組,差異有統(tǒng)計學(xué)意義(P0.01)。(3)低心率組肝右葉的平均ADC值、f值低于高心率組,差異具有統(tǒng)計學(xué)意義(P0.05)實驗二:(1)自由呼吸結(jié)合心電門控序列肝左、右葉SNR值均高于自由呼吸,差異有統(tǒng)計學(xué)意義(P0.05)。(2)兩次測量的ICC范圍,肝左、右葉ADC、D、f值均具有較好的一致性(左葉:0.869至0.987;右葉:0.776至0.980)。肝左、右葉D*值一致性較差(左葉:0.153 至 0.846;右葉:0.312 至 0.574)。(3)自由呼吸結(jié)合心電門控技術(shù)肝左葉ADC、D、f值兩次掃描測量值的可重復(fù)性好于自由呼吸,其中f值的可重復(fù)性最好(L0A為0.03%),D*值兩次掃描測量值的可重復(fù)性較自由呼吸差(L0A為20.95%)。自由呼吸結(jié)合心電門控技術(shù)肝右葉ADC、D*、f值兩次掃描測量值的可重復(fù)性較自由呼吸差,D*值的可重復(fù)性最差(L0A為14.75%);f值兩次掃描測量值的可重復(fù)性好于自由呼吸(L0A為0.03%)。IVIM-DWI參數(shù)值中,D*值的可重復(fù)性最差。(4)兩種采集技術(shù)肝左葉ADC、D值均大于肝右葉(P0.01);肝左葉D*值小于肝右葉(P0.01);肝左葉f值大于肝右葉,僅在自由呼吸條件下差異有統(tǒng)計學(xué)意義(P0.01)。(5)自由呼吸結(jié)合心電門控技術(shù)肝左、右葉的ADC、D、D*、f值低于自由呼吸,其中肝左葉間D*值差異不明顯(P=0.464),ADC值、D值、f值差異均有統(tǒng)計學(xué)意義(P0.05);肝右葉間D值(P=0.781)、D*值(P=0.161)間差異不明顯,ADC值f值(P0.01)差異均有統(tǒng)計學(xué)意義。實驗三:(1)自由呼吸結(jié)合心電門控心電門控技術(shù)獲得的肝臟IVIM-DWI圖像信噪比、對比噪聲比均高于自由呼吸(P0.01)。(2)兩種技術(shù)采集條件下肝臟良性病變的ADC值及IVIM參數(shù)值均高于肝臟惡性病變,差異具有統(tǒng)計學(xué)意義(P0.05)。(3)自由呼吸結(jié)合心電門控技術(shù)肝臟良、惡性病ADC值及IVIM參數(shù)值低于自由呼吸,兩者間僅惡性病變D*差異不顯著(P=0.073)。結(jié)論:(1)適當(dāng)?shù)目刂坪徒档托穆?可減少肝臟IVIM-DWI圖像運動偽影,從而獲得相對準(zhǔn)確的參數(shù)值,尤其是在肝左葉。(2)在肝臟IVIM-DWI成像時采用自由呼吸結(jié)合心電門控技術(shù)可明顯改善肝臟圖像質(zhì)量、提高圖像信噪比,尤其當(dāng)心率控制在70bmp以下時,肝臟圖像信噪比高、病灶顯示清晰,圖像質(zhì)量好。(3)自由呼吸結(jié)合心電門控技術(shù)對ADC值及IVIM相關(guān)參數(shù)大小及可重復(fù)性有一定影響,肝左葉效果更明顯,穩(wěn)定性更好。(4)ADC、D、D*、f值可用于肝臟良惡性病變的鑒別,但D*可重復(fù)性差,具有較高的測量誤差,建議臨床運用時應(yīng)慎重。
[Abstract]:Objective: To evaluate the ECG gating (electrocardiograph-triggered) technique on liver intravoxel incoherent motion imaging (magnetic resonance diffusion-weighted intravoxel incoherent motion imaging, IVIM-DWI) image quality, apparent diffusion coefficient (apparent diffusion, coefficient, ADC) and IVIM related parameters can affect the size and repeatability; at the same time on the basis of the research on the value of ECG gated IVIM-DWI technology in clinical diagnosis of liver diseases. Methods: Based on experiment one: during the period of May 2015 to December 2015 with 116 patients who received cardiac gated IVIM-DWI sequence scanning a set of volunteers, 6 B (b=0,50100150300600s/mm2), heart rate in subjects were divided into 2 groups, low heart rate group subjects the heart rate less than 70 BPM, high heart rate group subjects heart rate is greater than or equal to 80 beats per minute. Using the single index model and double linear function index The linear model is fitted by average ADC of scanning the whole liver IVIM-DWI images, and the D value, D* value and F value of pseudo color parameters. Select one of 3 consecutive layers as R0I placed in the selected level, level of left hepatic right lobe, each placed 3 100mm2 circular R0I, a total of 9 R0I each the average left, right hepatic ADC value, D value, D* value and F value, and statistical analysis. Experiment two: 18 young healthy volunteers during May 2016 to June 2016 in line with the conditions, each volunteer underwent two abdominal IVIM-DWI examination, the scanning process by free breathing, breath free combination two kinds of ECG gating technology to collect 5 liver IVIM-DWI images, b values of each 0,50100150300600s/mm2. sequence selection between the three layers of the image, respectively in the left hepatic parenchyma, and the abdominal wall and the 3 placed 100 mm2 circular R0I image analysis, get the corresponding strong liver signal Degree (signal intensity, SI), signal to noise (standard deviation, SD), the calculation of SNR value. The same way as the experimental one gets the average liver ADC value, D value, D* value and F value. The consistency of the evaluation of two measurements using paired t test, Pearson correlation coefficient and intraclass correlation coefficient ICC analysis. Two scan obtained ADC, D, evaluation method using Bland-Altman D* consistency and F values. The two kinds of technology in the right lobe of the left liver, the average SNR value, ADC value, D value, D* value and F value were analyzed. Experiment three: 66 cases collected from June 2016 to December 2016 in our hospital the diagnosis of focal liver lesions on parallel abdominal IVIM-DWI examination patients (85 lesions), all patients underwent conventional abdominal MR scanning and IVIM-DWI scanning, the freedom to breathe, breathe freely with ECG gated two techniques, B = 0,50100150300600s/mm2. respectively in the left hepatic lobe,. 璐，

本文編號：1612027