Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . There is a large left pneumothorax . While there is no shift of mediastinal structures , there is apparent flattening of the left hemidiaphragm and possible minimal widening of the left rib interspaces , which can be seen in tension . The right lung is clear ; no pleural effusion or pneumothorax is seen . Cardiac silhouette is not enlarged . Mediastinal contours are unremarkable .
    OUTPUT:
    
Large left pneumothorax . While no shift of the mediastinum , flattening of the left hemidiaphragm is seen and a tension component can not be excluded . The above findings were detected at 8 : 14 p .m . on ___ at which point a page was placed to Dr . ___ , awaiting callback at time of this dictation . Findings were discussed ___ Dr . ___ , ___ taking care of the patient , on ___ at 8 :25 PM via telephone .