Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A large left pleural effusion is again seen obscuring the lung from the level of the third intercostal space to the diaphragm , some of which is free pleural fluid seen shifting into the left apex on the lateral decubitus view . However , the pleural effusion has an unusual configuration with preservation of the left heart border which raises the possibility of a partially loculated effusion . The left lung apex is well aerated . The right lung is clear . No pneumothorax is present . The cardiac and mediastinal silhouettes are unchanged . Degenerative changes are again noted in the thoracic spine . Underlying left lower lobe consolidation can not be excluded .
    OUTPUT:
    
Large left pleural effusion is partially free pleural fluid , but may be partially loculated . If clinical concern persists , a followup CT could be considered for further evaluation .