單純腎囊腫能譜CT假強化特征

陳文錦　　蔡彩云　　王琦　　方文鑫

[關鍵詞] 腎囊腫;能譜CT;假強化;誤診

[中圖分類號] R692;R816.7? ? ? ? ? [文獻標識碼] B? ? ? ? ? [文章編號] 1673-9701（2021）20-0112-04

False enhancement characteristics of simple renal cyst with energy spectrum CT

CHEN Wenjin? ?CAI Caiyun? ?WANG Qi? ?FANG Wenxin

Department of Imaging，Xiamen no.5 Hospital of Fujian Province，Xiamen? ?361101， China

[Abstract] Objective To evaluate the false enhancement characteristics of simple renal cyst on energy spectrum CT scan. Methods The patients with simple renal cyst who were treated with energy spectrum CT and MRI scans in our hospital from January 2019 to January 2020 were reviewed.GSI Viewer analysis software was used for image processing，and the effects of renal cyst diameter，CT value，location and renal parenchyma density on false enhancement were measured. Results Ninety patients with renal cysts were enrolled in this study.A total of 122 cysts with diameters greater than 1 cm were detected.The incidence of false enhancement was significantly higher in cysts 1-2 cm in diameter than in cysts 2-3 cm in diameter （53%，36/68 vs. 15%，4/26，χ2=10.852，P=0.001）.The incidence of false enhancement of cysts was significantly higher in patients with renal parenchymal density >200 HU than in patients with renal parenchymal density ≤200 HU （50%，30/60 vs.17%，10/62，χ2=15.874，P=0.000<0.05）.The incidence of false enhancement in renal cysts was significantly higher than that in peripheral cysts （43%，28/65 vs. 21%，12/57，χ2=6.685，P=0.010）. The cyst size and renal parenchyma density after enhancement were risk factors for false enhancement. Conclusion Patients with the smaller cyst diameter and higher renal parenchyma density around the cyst should be on the alert for false enhancement to avoid misdiagnosis.

[Key words] Renal cyst; Energy spectrum CT; False enhancement; Misdiagnose

在我國，腎囊腫是常見的腎臟良性病變，50歲以上成人其發病率高達50%[1-2]。單純性腎囊腫無需干預及長期隨訪。CT增強掃描是臨床上診斷良性腎囊腫的主要方法。理論上單純腎囊腫邊緣清晰、外形規則、水樣密度，無強化[3]。而部分單純腎囊腫CT增強掃描后其CT值出現不同程度的增加，超過10 HU以上，這就是腎囊腫的假強化現象。假強化現象與容積效應、X線硬化、CT影像重建算法、解剖變異以及囊腫周圍腎組織干擾等因素有關[3-5]。直徑不超過2 cm的腎內小囊腫由于假強化現象的存在，使其與缺乏血供的腎內腫瘤鑒別困難，導致不必要的影像檢查或長期隨訪[6]。能譜CT可以提供病變有無強化的確切信息，有助于克服假強化現象，然而針對這一問題尚缺乏充分的臨床研究證實。因此，本研究探討能譜CT掃描模式下腎臟囊腫大小、位置等參數與假強化的關系，進一步評估能譜CT在克服假強化方面的效果。

1 資料與方法

1.1一般資料

收集2019年1月至2020年1月在我院放射科接受能譜CT增強掃描的單純性腎囊腫（Bosniak I型）患者。納入標準：年齡>18歲的成年患者接受腹部CT增強掃描;核磁共振檢查支持單純性囊腫診斷;核磁和CT掃描時間間隔3個月以內[5-7]。排除標準：腎臟周圍偽影嚴重影響囊腫測量;患者失訪;隨訪過程中腎囊腫直徑增大或密度增強不支持單純囊腫診斷[8]。