DuBrow R A, David C L, Curley S A
Department of Diagnostic Imaging, M.D. Anderson Cancer Center, Houston, TX 77030, USA.
AJR Am J Roentgenol. 1995 Sep;165(3):567-71. doi: 10.2214/ajr.165.3.7645472.
After low anterior resection of rectal carcinoma, anastomotic leaks are common and may be clinically silent. Radiologic abnormalities related to this leakage may be confusing and may persist for years without symptoms. The purpose of this study was to evaluate the appearance of these leaks on barium enemas and CT scans and to determine their course over time.
During a 7-year period, we collected CT scans and barium enemas in 35 patients with anastomotic leaks after low anterior resection. A leak was documented by the presence of rectal contrast material in an extraluminal collection, endoscopic visualization of anastomotic breakdown, or persistence of presacral air longer than 6 months after surgery. Twenty patients had examinations in the immediate postoperative period and 25 patients had 42 studies in the long-term follow-up period (6 months to 10 years). The CT appearance was compared with that in 40 patients who did not have evidence of leaks after low anterior resection.
Abnormalities consisted of air-fluid collections in the presacral space, extraperitoneal tracking along the iliac vessels, and perirectal anterior extension. Collections tended to diminish, but some air and soft-tissue masses persisted for months or years (up to 10 years in one case). In 70% of patients without leaks, no soft-tissue abnormality was apparent in the presacral space. In both groups of patients, the presacral space was widened and the rectum was anteriorly located, more so in patients with leaks than in those without. Seven patients had recurrent tumor. In the late stages, bulky soft-tissue masses obliterated the residual air and soft-tissue abnormality due to the leak.
Radiologists should be aware of the spectrum of findings due to anastomotic leaks after low anterior resection and the persistence of presacral abnormalities. Delayed symptoms mimic those of recurrence, and radiologic findings may be confusing. On some CT scans, it may not be possible to tell the difference, but changes due solely to leaks must be included in the differential diagnosis.
直肠癌低位前切除术后，吻合口漏很常见，且可能在临床上无明显症状。与这种渗漏相关的放射学异常可能令人困惑，且可能在无症状的情况下持续数年。本研究的目的是评估这些漏口在钡剂灌肠和CT扫描上的表现，并确定其随时间的变化过程。
在7年时间里，我们收集了35例低位前切除术后吻合口漏患者的CT扫描和钡剂灌肠资料。通过在腔外积液中发现直肠造影剂、内镜观察到吻合口破裂或术后骶前气体持续超过6个月来记录漏口情况。20例患者在术后即刻进行了检查，25例患者在长期随访期（6个月至10年）进行了42次检查。将CT表现与40例低位前切除术后无漏口证据的患者进行比较。
异常表现包括骶前间隙的气液积聚、沿髂血管的腹膜外蔓延以及直肠周围向前延伸。积液往往会减少，但一些气体和软组织肿块会持续数月或数年（1例长达10年）。在70%无漏口的患者中，骶前间隙未发现明显的软组织异常。两组患者中，骶前间隙均增宽，直肠向前移位，有漏口的患者比无漏口的患者更明显。有7例患者出现肿瘤复发。在晚期，巨大的软组织肿块掩盖了因漏口导致的残留气体和软组织异常。
放射科医生应了解低位前切除术后吻合口漏的各种表现以及骶前异常的持续情况。延迟出现的症状类似复发，放射学表现可能令人困惑。在一些CT扫描上，可能无法区分，但在鉴别诊断中必须考虑仅由漏口引起的变化。
