orbital fracture

fracture, orbital

A term relating to any break in the bony integrity of the orbital walls, most commonly occurring in the orbital floor or less frequently in the medial wall (called 'blow-out' fracture). Although most frequently resulting from blunt trauma, it may also result as a necessary step in surgical treatment (e.g. orbital decompression). There is periorbital bruising, oedema, haemorrhage, or enophthalmos. Diplopia and limited upward movement are present usually as a result of a muscle or its fascia being entrapped in the break. There may be concomitant intraocular injury if caused by trauma (e.g. tennis ball). Fractures in the orbital apex or roof are less common. The lateral wall of the orbit is very tough as it protects the globe and is only involved in very severe maxillofacial trauma.

Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann