Fig. 1From: Lung ultrasound in the critically ill (LUCI) and the lung point: a sign specific to pneumothorax which cannot be mimickedRegular M-mode outlook of a lung point. To the left, a seashore can be described, arising precisely from the pleural line. To the right, suddenly, a stratosphere sign is visible, that is, the total absence of any dynamic arising from the pleural line. An all-or-nothing rule, the lung point rules in pneumothoraxBack to article page