AP侵及肾旁后间隙的CT表现及其解剖学基础

CT features and anatomic basis of posterior pararenal space diffusion in AP

目的基于肾筋膜间平面的解剖概念,探讨肾筋膜外侧解剖附着分型为Ⅱ型的急性胰腺炎(AP)患者的肾旁后间隙扩散的CT表现及其受累的解剖途径。方法收集97例急性胰腺炎患者的临床和影像学资料。97例中,23例患者的一侧或双侧肾筋膜外侧附着解剖分型为Ⅱ型,且均有肾旁后间隙(PPRS)受累。回顾性分析23例中的PPRS受累的CT表现及其解剖学基础。结果 1)左侧PPRS和右侧PPRS受累分别为22例和9例;双侧PPRS受侵8例;2)PPRS受累表现为与同侧增厚的肾后筋膜后层和锥侧筋膜相连的条索影、斑片状影、条状积液,以及片团状积液影;3)PPRS受累的途径为:(1)肾旁前间隙的炎症先侵入肾后筋膜后层的筋膜间平面,再侵及PPRS;(2)肾旁前间隙的炎症直接通过增厚的肾后筋膜后层的薄弱处侵犯PPRS;(3)肾旁前间隙和/或肾前筋膜间平面的炎性积液向下进入锥下间隙,然后反折向上而侵犯PPRS。结论基于肾筋膜间平面的解剖,CT可良好显示肾筋膜外侧解剖附着分型为Ⅱ型的急性胰腺炎侵犯肾旁后间隙的解剖细节及其途径。

Objective To study CT features and anatomic basis of posterior pararenal space （PPRS） diffusion in acute pan- creatitis with type Ⅱ of lateral attachment of the renal fascia based on the concept of interfascial plane. Methods Clinical and imaging data of 97 patients with acute pancreatitis were collected. Among those patients, 23 patients with PPRS involvement resulting from acute pancreatitis were reviewed retrospectively, whose lateral or bilateral attachment of the renal fascia were type Ⅱ. Emphasis was placed on the CT findings of PPRS involvement and its anatomic route. Results 1 ） The left and right PPRS in- volvement was detected in 22 and 9 patients respectively. Bilateral PPRS involvement was detected in 8 patients; 2） CT features of PPRS involvement were strip shadow, patchy shadow and strip shape of fluid collection which were connected with the posterior renal fascia （PRF） , posterior layer of the PRF and lateral renal fascia, and mass shape of fluid collection in the PPRS; 3） Route of PPRS involvement ： ① the inflammation within the anterior pararenal sapce involved the interfascial plane of the posterior layer of PRF firstly, then involved the PPRS; ② the inflammation within the anterior pararenal sapce involved the PPRS directly through the weak point of thick posterior layer of PRF; ③ the fluid collection within the anterior pararenal space involved the in- fraconal space firstly, then involved the PPRS. Conclusion CT can show the anatomic route of PPRS involvement by acute pan- creatitis whose lateral attachment of the renal fascia were type Ⅱ in detail.