Enophthalmos

The sinking of the eyeball towards the back part of the eye socket. Enophthalmos becomes clinically obvious if the anterior globe projection is less than 12 mm or differs from the opposite side by 3 mm or more as measured by a Hertel exophthalmometer. The anterior projection of the eye is most commonly measured relative to the outer edge of the orbit, the orbital rim, but may also be assessed relative to the frontal and maxillary prominences, or the contralateral eye.

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