85-95% of pneumoperitoneum is associated with gastrointestinal perforation, but in the absence of peritoneal signs, fever, or leukocytosis, a perforated bowel becomes less likely. If there is another evident cause for free air under the diaphragm in addition to a lack of clinical signs and symptoms associated with perforated bowel, then surgery may not be necessary and may expose the patient to unnecessary risk. A radiologist can assist the clinical counterparts by identifying potential alternative sources of pneumoperitoneum relevant to the patient such as recent pneumothorax with chest tube placement identified by chest x-ray in this patient.