Comet Tail Artifact/B Lines
• Vertical lines, extending from the pleural line to the edge of the screen without fading
• Synchronized with lung sliding
• When present they will usually overshadow the A lines
• Represents thickening interlobular septa and extravascular lung water as in alveolar interstitial disease (pulmonary edema, ARDS...)
• Their presence mostly rules out pneumothorax