The Coca-Cola bottle sign refers to the appearance of the muscles of the orbit in thyroid eye disease. The belly of the muscle enlarges with sparing of the tendinous insertion, giving the appearance of the traditional Coca-Cola bottle.
The enlargement of the muscles follows the I'M SLOW format.
The nature of the enlargement is important as it is one of the chief findings to differentiate it from orbital pseudotumour, in which the tendinous insertion is also involved and enlarged, unlike in thyroid eye disease.
- 1. Lund V, Larkin G, Fells P et-al. The Journal of Laryngology & Otology. 1997;111 (11): . doi:10.1017/S0022215100139313