<prompt> All are true about Kerley B line except:HorizontalRuns from hilar area to peripheral areaDue to thickening of septaDue to pulmonary venous hypeension  <response>: B i.e. Runs from hilar area to peripheral area Kerley A lines radiate from hilum not kerley B lines which are best seen in costophrenic anglesQ. Kerley lines Kerley B lines Horizontal transverseQ, non branching 1-2 mm thick, 1-3 cm long lines at lung base best seen at costophrenic anglesQ are perpendicular to pleural surface2 Seen at PCWP 17-20 mmHgQ Due to thickening of interlobular septaQ caused by: Pulomonary venous hypeensionQ MS, LVF Lymphatic obstruction pneumoconiosis, Lymphangitis carcinomatosis, sarcoidosis Interstial pneumonitis Kerley A lines 1-2 mm thick, 2-6 cm long non branching lines radiating from the hilumQ D t thickened deep interlobular septa Kerley C lines Fine interlacing lines throughout the lung producing spider web appearance 