Presentation
Acute abdominal pain.
Patient Data
Age: 45 years
Gender: Male
From the case:
Bowel perforation - subdiaphragmatic free gas
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An erect abdominal x-ray reveals crescentic gas under the right diaphragm.
Case Discussion
Subdiaphragmatic free air has a limited diffrential diagnosis including: pneumoperitoneum, chilaiditi syndrome, situs inversus and subdiaphragmatic abscess.
Erect chest x-rays covering the upper abdomen are often considered the best for detecting free subdiaphragmatic gas but an erect abdominal x-ray covering the lung bases will be just as sensitive.