本文選題：體層攝影術(shù)　切入點：X線計算機　出處：《天津大學》2012年碩士論文　論文類型：學位論文

【摘要】：CT低劑量參數(shù)優(yōu)化的研究,近些年來一直是大家關注的熱點不同的領域從如何設計及優(yōu)化CT低劑量掃描方案重建算法等方面進行探索，使受檢者在接受較低輻射劑量的同時獲得較好的有足夠診斷信息的圖像本課題研究旨在通過實驗得到不同人體掃描部位CT低劑量掃描最優(yōu)曝光參數(shù)，降低輻射劑量，為影像技師提供合理的掃描參數(shù) 針對目前CT低劑量的研究多集中在改變掃描參數(shù)上，本研究引入體型因素作為修正，選擇與圖像質(zhì)量相關性最大的體厚周徑元素，依據(jù)受檢者體厚周徑的不同，設定掃描參數(shù)，并與常規(guī)參數(shù)的圖像質(zhì)量及輻射劑量對比，以探討在圖像滿足臨床診斷的同時，體厚周徑指導降低CT掃描劑量的可行性，最終得出臨床實際應用的合理參數(shù) 本研究首先對QA模體進行不同KV mAs的掃描，分析圖像質(zhì)量評價參數(shù)包括密度分辨率空間分辨率均勻性及噪聲，在其符合中華人民共和國國家計量檢定規(guī)程中的醫(yī)用診斷螺旋計算機斷層攝影裝置（CT）X射線輻射源檢定規(guī)程，即文件JJG1026一2007要求的前提下，篩選出合理的低劑量掃描參數(shù)然后對不同體厚的頭胸腹各270例受檢者行低劑量參數(shù)掃描，通過對低劑量掃描圖像的對比評價及噪聲的定量測量，在圖像具有一定的密度分辨率空間分辨率均勻性及適度噪聲滿足臨床診斷的前提下，得出不同體厚受檢者最優(yōu)掃描參數(shù)，使得輻射劑量最低最后將最優(yōu)參數(shù)應用于病例組，頭胸腹各60例患者，與常規(guī)掃描參數(shù)進行比較，進一步驗證并修正掃描參數(shù)，應用于臨床 研究表明對受檢者進行體型分類后行低劑量掃描與之前所有患者均采用統(tǒng)一常規(guī)劑量掃描的方法比較，在不降低圖像診斷結(jié)果的情況下，總體掃描劑量有大幅降低，頭胸腹平均掃描劑量降低分別約為28%39%27%患者的受照劑量趨于合理化，，達到了圖像質(zhì)量與射線劑量的均衡，具有良好的社會效益
[Abstract]:In recent years, the research on the optimization of low dose CT parameters has been a hot topic in different fields, such as how to design and optimize the reconstruction algorithm of low dose CT scanning schemes, and so on. The purpose of this study is to get optimal exposure parameters of CT low dose scanning in different human body scanning sites through experiments, and to reduce radiation dose. Provide reasonable scanning parameters for image technician. In view of the current research of CT low dose is focused on changing the scanning parameters, this study introduces the body shape factor as a correction, and selects the body thickness circumference element, which has the greatest correlation with image quality, according to the difference of the body thickness circumference of the subject. The scanning parameters are set, and compared with the image quality and radiation dose of conventional parameters, so as to discuss the feasibility of reducing CT scanning dose under the guidance of body thickness circumference while the image meets the clinical diagnosis. Finally, the reasonable parameters for clinical application are obtained. In this study, the QA motifs were scanned with different KV mAs, and the image quality evaluation parameters including density resolution spatial resolution uniformity and noise were analyzed. In accordance with the verification regulation of the medical diagnostic helical computed tomography equipment of the people's Republic of China in the national metrological verification regulation, namely, the document JJG1026-2007, The reasonable low dose scanning parameters were screened, and 270 cases of head, chest and abdomen with different body thickness were scanned with low dose parameters. The contrast evaluation of low dose scanning images and the quantitative measurement of noise were carried out. Under the premise that the image has a certain spatial resolution uniformity of density resolution and moderate noise to satisfy the clinical diagnosis, the optimal scanning parameters of the patients with different body thickness are obtained, so that the optimal parameters are applied to the case group at the end of the radiation dose. 60 patients with head, chest and abdomen were compared with the conventional scanning parameters. The parameters were further verified and modified, and applied to clinical practice. The study showed that the total scanning dose was significantly reduced without lowering the diagnostic results of the image, compared with that of all the previous patients using the unified routine dose scanning method after the classification of the body types of the subjects. The average scanning dose of head, chest and abdomen decreased by about 289% of the patients respectively, and the radiation dose tended to be rationalized, which achieved the balance between the image quality and the dose of radiation, and had good social benefit.
【學位授予單位】：天津大學
【學位級別】：碩士
【學位授予年份】：2012
【分類號】：R814.42

【參考文獻】

相關期刊論文 前5條

1 胡榮慧,宋光義,韓丹,許立奇,張良,成友華;螺旋CT檢測肺結(jié)節(jié)的低劑量優(yōu)化選擇及應用[J];放射學實踐;2005年07期

2 余曉鍔;占杰;張寧;;多層面CT機劑量的測量與分析[J];中國醫(yī)學物理學雜志;2005年06期

3 江一峰;葉劍定;陳群慧;沈艷;;多層螺旋CT低劑量掃描篩查及定性診斷肺微小結(jié)節(jié)的臨床應用[J];診斷學理論與實踐;2010年02期

4 劉昌盛,魏文洲,鄭曉華,童世平,殷響林,楊洪飆;低劑量CT掃描對嬰幼兒顱腦病變檢查的防護價值[J];中華放射醫(yī)學與防護雜志;2004年03期

5 朱曉華,李士駿,薛永明,邵江,史景云,尤正千;胸部CT低劑量掃描的圖像質(zhì)量與吸收劑量關系分析[J];中華放射學雜志;2003年10期

本文編號：1568853