CXR AP (above left) shows a hazy opacity projecting over the apex of the heart while the CXR lateral (above right) places the hazy opacity over the last vertebral body that is completely above the diaphragm. Note on the lateral that over the spine, the lung is not getting more lucent going from lung apex to lung base because of this hazy opacity (spine sign). Sagittal CT without contrast of the left hemithorax of the chest (below) shows a dense opacity in the posterior aspect of the left lower lobe.
