Toh James Wei Tatt, Collins Geoffrey Peter, Ridley Lloyd J, Chan Michael, Schofield Reid
Discipline of Surgery, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
Colorectal Department, Westmead Hospital, Sydney, New South Wales, Australia.
J Med Imaging Radiat Oncol. 2023 Apr;67(3):252-259. doi: 10.1111/1754-9485.13454. Epub 2022 Jun 30.
Sigmoid volvulus is a potentially devastating and life-threatening condition associated with sigmoid colon redundancy. Many of the classical radiological signs are considered to represent the two adjacent loops of bowel in a mesentero-axial volvulus. However, limited case reports and series have reported on an organo-axial subtype of sigmoid volvulus. This clinical entity is not widely understood. In this study, we assess the radiological and clinical features of mesentero-axial and organo-axial sigmoid volvulus.
After institutional board approval (CH62/6/2016-228), all computed tomography (CT) studies from 2011 to 2017 reported as sigmoid volvulus at a single institution were reviewed. The cases were reviewed by three radiologists retrospectively and the course of the bowel followed with a focus on assessing its rotational axis. In each case, the sigmoid volvulus was independently subclassified as mesentero-axial or organo-axial volvulus based on the axis of rotation of the volvulus. In addition, X-ray signs including disproportionate sigmoid dilatation, distended inverted 'U' in sigmoid, coffee bean sign, opposed wall sign, direction of apex of sigmoid loop, liver overlap sign, northern exposure sign and proximal colonic dilatation and CT features including whirl sign, 'X' marks the spot sign, split wall sign and number of transition points were reported for each case. The clinical management and outcomes including morbidity, mortality, endoscopic decompression and need for surgery were also evaluated. The subtype of volvulus was correlated with the above X-ray signs, CT features and clinical management and outcomes. Statistical analysis was conducted using Stata/MP, version 15 (StataCorp LP, College Station, TX, USA).
A total of 38 scans were reviewed. There were 19 patients identified. Of these, six (32%) were reported as mesentero-axial and 13 (68%) as organo-axial volvulus. No X-ray signs were able to distinguish the two types of volvulus. The number of transition points on CT was predictive of volvulus subtype (OR 25, 95% CI: 1.30-1295.30, P = 0.01). Within the limitations of a small cohort, there was no statistically significant difference in unsuccessful endoscopic decompression, need for colectomy, repeated admissions or mortality between the groups.
This study has demonstrated that organo-axial sigmoid volvulus may be as common as mesentero-axial volvulus. Distinguishing organo-axial from mesentero-axial volvulus can be achieved on CT, but not on abdominal X-ray. The number of transition points (two for mesentero-axial and one for organo-axial) may be used as a diagnostic feature for differentiating the two forms of volvulus.
乙状结肠扭转是一种与乙状结肠冗长相关的潜在破坏性且危及生命的疾病。许多经典的放射学征象被认为代表了肠系膜轴性扭转中相邻的两个肠袢。然而，有限的病例报告和系列研究报道了乙状结肠扭转的器官轴性亚型。这种临床实体尚未得到广泛理解。在本研究中，我们评估了肠系膜轴性和器官轴性乙状结肠扭转的放射学和临床特征。
经机构委员会批准（CH62/6/2016 - 228）后，对2011年至2017年在单一机构报告为乙状结肠扭转的所有计算机断层扫描（CT）研究进行了回顾。三位放射科医生对病例进行了回顾性分析，并追踪肠管的情况，重点评估其旋转轴。在每个病例中，根据扭转的旋转轴，乙状结肠扭转被独立分类为肠系膜轴性或器官轴性扭转。此外，报告了每个病例的X线征象，包括不成比例的乙状结肠扩张、乙状结肠内扩张的倒“U”形、咖啡豆征、对壁征、乙状结肠袢顶端的方向、肝脏重叠征、北向暴露征和近端结肠扩张，以及CT特征，包括漩涡征、“X”标记征、裂壁征和移行点数量。还评估了临床管理和结局，包括发病率、死亡率、内镜减压和手术需求。扭转的亚型与上述X线征象、CT特征以及临床管理和结局相关。使用Stata/MP 15版本（美国德克萨斯州大学站StataCorp LP公司）进行统计分析。
共回顾了38次扫描。确定了19例患者。其中，6例（32%）报告为肠系膜轴性扭转，13例（68%）为器官轴性扭转。没有X线征象能够区分这两种类型的扭转。CT上的移行点数量可预测扭转亚型（比值比25，95%置信区间：1.30 - 1295.30，P = 0.01）。在小样本队列的局限性内，两组在内镜减压失败、结肠切除术需求、再次入院或死亡率方面没有统计学显著差异。
本研究表明，器官轴性乙状结肠扭转可能与肠系膜轴性扭转一样常见。在CT上可以区分器官轴性和肠系膜轴性扭转，但在腹部X线上则无法区分。移行点数量（肠系膜轴性为两个，器官轴性为一个）可作为区分这两种扭转形式的诊断特征。
