Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged . There are patchy basilar opacities , more extensive on the left than right , and fairly similar to the prior radiographs , although these had cleared at the time of the CT . There is no pleural effusion or pneumothorax . Mild similar rightward convex curvature is centered along the upper thoracic spine .
    OUTPUT:
    
Patchy bibasilar opacities , more confluent on the left than right . Noting predominantly streaky character and low lung volumes , atelectasis could be considered ; in the appropriate clinical setting , however , pneumonia would be a possibility .