Question

2 X-rays (Erect & Supine) were given to identify the condition [Image shows erect and supine chest X-rays with air under diaphragm on erect view]

• A. Empyema Thorax
• B. Liver abscess
• C. Gastric volvulus
• D. Hollow viscus perforation

Hint:

Free gas under the diaphragm on an erect X-ray is pathognomonic of one specific emergency -- identify it correctly.

Answer 1

The Correct Option is D

X-ray Interpretation: Erect and Supine views

Key sign: Pneumoperitoneum = free air under the right hemidiaphragm on erect chest X-ray

Diagnosis: Hollow Viscus Perforation

Radiological signs of pneumoperitoneum:

• Erect CXR: Crescent of air under the right (or both) hemidiaphragm(s) -- most sensitive plain film sign; as little as 1 mL of free air can be detected
• Supine AXR: Rigler's sign (double wall sign) -- both inner and outer bowel wall visible; football sign (large ovoid lucency over the abdomen); falciform ligament sign
• Lateral decubitus: Air collects between liver and lateral abdominal wall

Common causes of pneumoperitoneum:

• Perforated peptic ulcer (most common)
• Perforated appendix
• Iatrogenic (post-laparoscopy -- physiological within 48 hours)
• Perforated diverticulitis

\[\boxed{\text{Answer: Hollow Viscus Perforation}}\]