Tuberculosis (TB) is a contagious-infectious disease caused mainly by <i>Mycobacterium tuberculosis</i> that in most individuals is usually asymptomatic but that in at risk individuals (e.g. with diabetes or with HIV infection) can cause weakness, fever, weight loss, night sweat, and respiratory anomalies such as chronic cough, chest pain, hemoptysis or respiratory insufficiency.

A fold of skin starting above the medial aspect of the upper eyelid and arching downward to cover, pass in front of and lateral to the medial canthus.