From the Guidelines
Sigmoid volvulus on abdominal X-ray (AXR) is typically characterized by the "coffee bean" sign, which is a strong indicator of this condition, as recommended by the WSES consensus guidelines on sigmoid volvulus management 1. The "coffee bean" sign appears as a large, dilated loop of bowel resembling a coffee bean or the Greek letter omega, usually positioned in the upper abdomen. Other common signs include the "bent inner tube" appearance, where the twisted sigmoid colon creates a smooth, curved, dilated loop, and the "northern exposure" sign, which shows the apex of the dilated sigmoid loop extending above the transverse colon 1. Some key points to consider when evaluating AXR for sigmoid volvulus include:
- Absence of rectal gas, as the twisted sigmoid prevents gas from passing distally
- Multiple air-fluid levels, indicating obstruction
- The "frimann-dahl" sign, which shows three white lines converging toward the site of torsion These findings, especially when combined with clinical symptoms of abdominal pain, distension, and constipation, strongly suggest sigmoid volvulus and warrant urgent surgical consultation for decompression via sigmoidoscopy or surgery to prevent bowel ischemia and perforation, as recommended by the WSES consensus guidelines 1. It is essential to note that while AXR is often diagnostic, CT imaging can be used in cases where the diagnosis is in doubt or if ischemia or perforation is suspected, as it can provide more detailed information and help confirm the diagnosis 1.
From the Research
Sigmoid Volvulus Radiography Signs on AXR
- The plain X-ray of the abdomen is helpful in diagnosing sigmoid volvulus, as stated in the study 2.
- Radiographs show a dilated sigmoid colon and multiple small or large intestinal air-fluid levels, as mentioned in the study 3.
- Abdominal X-ray can demonstrate signs of sigmoid volvulus, including a large, dilated sigmoid colon and multiple air-fluid levels, as indicated in the study 4.
- The sensitivity of abdominal X-ray in the diagnosis of acute large bowel volvulus is an important aspect of diagnosis, as discussed in the study 4.
- While the studies provide information on the management and diagnosis of sigmoid volvulus, they also highlight the importance of radiography signs on AXR, including:
- Dilated sigmoid colon
- Multiple small or large intestinal air-fluid levels
- Abdominal distention and tenderness, as mentioned in the study 3