Pleural Effusion

A 65-year-old male presents with progressive dyspnea. A chest X-ray (PA view) reveals blunting of the right costophrenic angle and a curvilinear opacity extending upwards along the lateral chest wall. Which of the following is the most likely radiological finding described?

A 50-year-old patient with a history of congestive heart failure presents with acute worsening dyspnea. A chest X-ray shows bilateral, symmetrical pleural effusions with associated cardiomegaly. Which type of pleural effusion is most likely present?

A patient is suspected of having a small, loculated pleural effusion that is not clearly visible on a standard upright chest X-ray. Which imaging modality is considered most sensitive and effective for detecting and characterizing such effusions, and for guiding aspiration?

A 45-year-old male presents with fever, pleuritic chest pain, and a large, loculated left-sided pleural effusion. A CT scan of the chest with contrast reveals a thickened, enhancing visceral and parietal pleura separated by the fluid collection, a finding known as the 'split pleura sign.' This sign is most characteristic of which condition?

A 70-year-old smoker presents with weight loss, cough, and a new, large, unilateral right-sided pleural effusion on chest X-ray. There is no evidence of cardiomegaly or pulmonary edema. Which of the following is the most likely underlying cause of this pleural effusion?