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What is A single retrocardiac air-fluid level on a chest radiograph typically implies the presence of: and explain in detail?
Ref: Canadian Asso Radiology journal, 1986Explanation:Sliding hiatus hernia is the most common type of hiatus herniaThe GE junction is displaced upwardsThe gastric fundus is also displaced above the diaphragm - retrocardiac mass with air fluid levelA differential (2 airfluid levels at different interfaces) retrocardiac air-fluid level - gastric volvulus.Pericardial effusion produces water bottle' appearance of cardiac silhouette on CXRLung abscess produces a cavity with airfluid level