May Be Caused by

 Common

Atelectasis

Bronchogenic carcinoma

Epicardial fat pad

Esophagectomy with colon interposition

Esophagectomy with gastric pull-up

Hiatal hernia

Loculated pleural effusion

Morgagni hernia

Pericardial cyst

Pericardial diverticulum

Pleural adhesions

Pneumonia

 Uncommon

Cardiac aneurysm

Cardiac neoplasm

Diaphragmatic neoplasm

Diaphragmatic rupture

Extralobar pulmonary sequestration

Herniation of liver

Hydatid cyst

Juxtapericardial lymphadenopathy

Localized fibrous tumor of pleura

Lymphoma

Malignant germ cell neoplasm

Mature teratoma

Metastasis

Pericardial effusion

Pericardial mesothelioma

Pleural mesothelioma

Thymic carcinoma

Thymic cyst

Thymolipoma

Thymoma