Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left pneumothorax is unchanged . There is no mediastinal shift . Dense material in the left hemi thorax on has a more dependent position suggestive of intrathoracic contrast . Cardiomediastinal silhouette and pulmonary vasculature are within normal limits . There is no consolidation . Cardiac device generator overlying the left chest is unchanged with leads in the right atrium , right ventricle , and coronary sinus .
    OUTPUT:
    
Unchanged left pneumothorax without evidence of mediastinal shift .