Images in surgery

Afferent loop syndrome secondaryto Billroth II gastrojejunostomyobstruction: Multidetector computedtomography findingsSabri Yilmaz, MD,a Ensar Yekeler, MD,a Cem Dural, MD,b Memduh Dursun, MD,a Yakup Akyol, MD,a

and Bulent Acunas, MD,a Istanbul, Turkey

From the Departments of Radiologya and General Surgery,b Istanbul University, Istanbul Faculty of Medicine,

This section features outstanding photographs of clinical materials selected for theireducational value or message, or possibly their rarity. The images are accompanied bybrief case reports (limit 2 typed pages, 4 references). Our readers are invited to sumititems for consideration.

Istanbul, Turkey

A 69-year-old man with a history of a perforatedgastric ulcer, necessitating operation 30 years earlier,presented to the emergency room with epigastricpain, nausea, and vomiting. Physical examinationshowed diffuse abdominal tenderness, rebound anddefense. Abnormal laboratory findings were a whiteblood cell count of 8.7 � 109/L, total bilirubin levelof 3.8 mg/dL (direct bilirubin � 2.47 mg/dL),alkaline phosphatase level of 865 U/L, aspartateaminotransferase level of 297 U/L, an amylase levelof 1114 U/L, and urine amylase level of 9459 U/L.Preliminary diagnosis of biliary pancreatitis wassuggested due to the high amylase levels. However,diagnosis of afferent loop syndrome (ALS) wasmade on a multidetector computed tomography(CT) on the basis of the presence of a fluid-filled,tubular structure extending from the gallbladder

Accepted for publication February 18, 2006.

Reprint requests: Dr. Sabri Yilmaz, Istanbul University, IstanbulFaculty of Medicine, Department of Radiology, Millet Caddesi,Capa, Istanbul, Turkey. E-mail: yilmazsdr@yahoo.com.

Surgery 2007;141:538-9.

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© 2007 Mosby, Inc. All rights reserved.

doi:10.1016/j.surg.2006.02.024

538 SURGERY

fossa, crossing the midline, and terminating at thelevel of the anastomosis site of gastrojejunostomy(Figs 1 and 2). Intrahepatic and extrahepatic biliarydilatation were also observed. Laparotomy showeda resection of the lower two-thirds of the stomachand a Billroth II gastrojejunostomy. A severe dila-tation of the afferent loop was detected due to anadhesion mechanically obstructing the anasto-mosis. An adhesiolysis was carried out to providebiliary passage. The postoperative course was un-eventful.

DISCUSSIONAfferent loop syndrome is an uncommon com-

plication that occurs in 0.3% of the patients aftersubtotal gastrectomy and Billroth II gastrojejunos-tomy. Prompt recognition and correct diagnosis ofthis syndrome and its probable etiology are importantas a guide for treatment.1 The clinical diagnosis maybe difficult, as the symptoms of ALS are nonspecificand include postprandial fullness, intermittent epi-gastric, and right upper quadrant pain relieved bybilious vomiting, and, rarely, obstructive biliarysigns and acute pancreatitis.2 Most cases of afferentloop syndrome are due to obstruction from adhe-sions, kinking at the anastomosis, intussusception,

internal hernia, stomal stenosis, malignancy, or in-

Surgery Yilmaz et al 539Volume 141, Number 4

flammation surrounding the anastomosis.3 In thepresent case, laparotomy showed an adhesion atthe anastomosis site as the cause of obstruction.

Computed tomography and ultrasound (US)are useful in establishing the diagnosis of afferentloop syndrome. The fluid-filled dilated, afferentportion of small bowel can be identified readilyby means of both imaging modalities. In 1980,Kuwabara et al4 first reported the CT findings ofALS in the radiologic literature. These findings arequite characteristic: the dilated afferent loop isseen in the mid abdomen, typically located at thehorizontal part of the duodenum, between theaorta and the superior mesenteric vessels, displac-ing them anteriorly.4 It appears as a U-shaped,fluid-filled tubular structure with a few stretchedvalvulae conniventes usually seen within it, knownas “the keyboard sign.”1 As in our case, complica-tions of afferent loop syndrome such as a dilatedgallbladder, biliary dilatation, and pancreatitis areidentified readily at CT and US.2 Pancreatitis sup-

Fig 1. Contrast-enhanced axial multidetector CT imageat the mid-abdomen shows the dilated gallbladder (GB),common bile duct (black arrow), main pancreatic duct(arrowhead), fluid-filled dilated afferent loop (AL), andthe obstruction site (white arrow).

ported by high amylase levels was the differential

clinical consideration in the present case. Becausethe clinical signs and symptoms are generally non-specific and operation is usually necessary to relievethe mechanical obstruction, it is important to es-tablish the diagnosis of afferent loop syndrome byimaging modalities, especially with multiplanar re-constructed multidetector CT images, which showsthe post-operative anatomy better.

REFERENCES1. Kim HC, Han JK, Kim KW, Kim YH, Yang HK, Kim SH, et al.

Afferent loop obstruction after gastric cancer surgery: helicalCT findings. Abdom Imaging 2003;28:624-30.

2. Gayer G, Barsuk D, Hertz M, Apter S, Zissin R. CT diagnosisof afferent loop syndrome. Clin Radiol 2002;57:835-9.

3. Fischer JE, Fegelman E, Johannigman J. Surgical complica-tions. In: Schwartz SI, ed. Principles of surgery. 7th ed. NewYork: McGraw-Hill; 1999. p. 441-84.

4. Kuwabara Y, Nishitani H, Numaguchi Y, Kamoi I, Matsuura K,Saito S. Afferent loop syndrome. J Comput Assist Tomogr

Fig 2. Coronal curved-planar reconstructed multidetec-tor CT image nicely shows the dilated afferent loop (AL)and the obstruction at the anastomosis site (arrowheads)in addition to dilated common bile duct (arrow) andgallbladder (GB).

1980;4:687-9.