Gallstone ileus: imaging diagnosis

Abstract

ntroduction. Gallstone ileus (GI) is a rare complication of biliary lithiasis, being registered in about 4% as a potential cause of intestinal obstruction (IO). GI is imagistically characterized by the pathognomonic sign – the Rigler triad (RT): pneumobilia (P), IO signs, calculus (C) in the intestinal lumen, which may be present to varying degrees in various imaging investigations. Aim of the study. Analysis of the rate of presence of RT elements in the imaging investigations applied in GI diagnosis. Materials and methods. Retrospective study based on 7 cases with GI treated in the Institute of Emergency Medicine, period 2014-2018. We studied the frequency of the presence of RT: complete or incomplete (no less than two components). Results. Men - 2 (28.5%), women - 5 (71.4%), average age - 80.1 ± 1.9 (95% CI: 75.39-84.99). M:W-1:2.5 ratio. All patients had aggravated medical history, average Charlson Comorbidity Index was 8.5 points. These data are in accordance with the data of the specialized literature. Abdominal radiography performed in 6 (85.7%) cases, showed only radiological signs of intestinal obstruction (air-fluid levels and arches) in 4 patients (66.6%), which does not indicate the absence of GI. Contrast CT examination, performed in 4 patients (57.1%), recorded complete RT and air in the gallbladder, only in one case (25%). In other 3 cases: P + C (n = 1), signs of IO and C (n = 2), P (n = 1). The presence of at least 2 radiological criteria from RT induces the diagnosis of GI. Basically, we can find the presence of RT elements in 3 CT images: 1 complete and 2 incomplete (75%) Conclusions. The Rigler triad, according to the literature data, can be omitted in the abdominal radiological examination, being registered at CT with an accuracy of about 75%, so we can assume that CT is useful in the rational diagnosis plan in an elderly patient, presented with signs of intestinal occlusion.