Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since condition required examination in sitting semi-upright position using AP frontal and left lateral views . Analysis is performed in direct comparison with the next preceding AP single view chest examination of ___ . The patient is very heavy , a fact which detracts from the ability to assess pulmonary vasculature with confidence . Comparison is made with the next preceding AP single view chest examination of ___ . The patient is status post orthopedic stabilization of the lower thoracic and lumbar spine ___ rods identified . Relatively high positioned diaphragms result in crowded appearance of the pulmonary vasculature on the bases . Heart size is difficult to assess but probably mildly enlarged with a configuration favoring the left ventricle with prominence to the left and posteriorly . No significant left atrial enlargement can be identified . No new discrete pulmonary parenchymal infiltrates are seen . Comparison to the pulmonary vasculature suggests a somewhat increased upper zone redistribution pattern with more distended pulmonary veins in the upper zone area . There is , however , no conclusive evidence for any new pleural effusion and no pneumothorax is seen in the apical area .
    OUTPUT:
    
Increased upper zone redistribution pattern may match clinical findings of shortness of breath . Radiographic interpretation of vascular pattern difficult in this very adipose patient . No pneumothorax is seen .