本文選題：能譜　切入點：智能匹配　出處：《臨床放射學雜志》2017年07期

【摘要】：目的評估能譜CT智能匹配技術(GSI assist)在不同體質量指數(BMI)患者腹部CT掃描中的圖像噪聲和輻射劑量,并與120 kVp常規(guī)掃描進行對比研究。方法搜集行能譜CT全腹部增強掃描患者76例,掃描前記錄每例患者的BMI。平掃采用120 kVp、自動管電流調制掃描,采用濾波反投影(FBP)、30%和50%自適應統(tǒng)計迭代重建(ASiR)3組圖像;增強采用GSI成像模式,打開GSI assist并設置與平掃相同噪聲指數,自動選擇最佳能譜參數掃描,重建靜脈期65 keV單能量圖像。根據患者BMI將所有患者分為4組,A組:BMI18.5 kg/m~2;B組:BMI18.5~23.9 kg/m~2;C組:BMI 24~28.9 kg/m~2;D組:BMI≥29 kg/m~2。記錄各組患者常規(guī)120 kVp和GSI assist兩種掃描模式的容積CT劑量指數(CTDIvol),并測量4組圖像腹壁皮下脂肪和膀胱的圖像噪聲。采用配對t檢驗比較各組患者GSI assist模式掃描和常規(guī)120 kVp掃描的圖像噪聲和輻射劑量。結果 GSI assist模式掃描和常規(guī)120 kVp掃描的CTDIvol在各組分別為:A組:(8.2±2.3)mGy和(6.5±2.2)mGy;B組:(11.3±3.2)mGy和(10.8±3.4)mGy;C組:(17.9±3.7)mGy和(18.3±4.3)mGy;D組:(18.9±4.7)mGy和(20.4±5.6)mGy。GSI assist模式掃描CTDIvol在A組低于120 kVp常規(guī)掃描(P0.05),在B組和C組與120 kVp常規(guī)掃描差異無統(tǒng)計學意義(P0.05),在D組高于120 kVp常規(guī)掃描(P0.05)。4組患者65 keV單能量圖像皮下脂肪和膀胱噪聲均低于120 kVp聯(lián)合FBP圖像(P0.05),高于120 kVp聯(lián)合50%ASiR圖像(P0.05),與120 kVp聯(lián)合30%ASiR圖像差異無統(tǒng)計學意義(P0.05)。結論能譜CT智能匹配技術可以降低低BMI患者的輻射劑量;其65 keV單能量圖像噪聲與常規(guī)120 kVp掃描聯(lián)合30%ASiR圖像相當,低于常規(guī)掃描FBP重建圖像。
[Abstract]:Objective to evaluate the image noise and radiation dose of energy dispersive CT intelligent matching technique (GSI assist) in abdominal CT scans of patients with different body mass index (BMIs). Methods 76 patients with total abdominal enhanced scanning with energy dispersive computed tomography (EDS) were collected and compared with the conventional scan of 120 kVp. The BMIs of each patient were recorded before scanning. The normal scan was performed with 120kVp, and the automatic tube current modulation scan was used. The 30% and 50% adaptive statistical iterations of filtering backprojection are used to reconstruct the three groups of images, the GSI imaging mode is used to enhance the image, the GSI assist is opened and the same noise index is set up with the same noise index as the plain scan, and the best energy spectrum parameter scan is automatically selected. All patients were divided into 4 groups according to BMI. Group A was divided into 4 groups: group A: BMI18.5 / kgmmm2OB group: BMI18.5kg / kg / m2KM group (group C): BMI18.5kg / kg / m-1 group (group C): BMI249kg / mmm2D group: BMI 鈮，

本文編號：1653956