What is lingular subsegmental atelectasis?

Partial Collapse: The lingula is the lower anterior (front) portion of the left upper lobe of the lung that corresponds to the right middle lobe. Atelectasis is collapse of a portion of the lung. So, subsegmental atelectasis means that portions of lung segments of the lingula are incompletely aerated. May indicate bronchial blockage, poor breathing, or even early infection.