Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph was provided . A Port - A - Cath resides over the right lower chest wall with catheter tip extending to the level of the mid SVC . There is improved aeration in the lower lungs compared with prior study . A retrocardiac air - filled density is compatible with a hiatal hernia . There is no pneumothorax . No signs of pneumonia . Mediastinal contour are normal . Bony structures are intact .
    OUTPUT:
    
Large hiatal hernia noted . Improved aeration in the lower lungs . Port - A - Cath positioned well .