proptosis
Pronunciation: prop-TOH-sis
Forward displacement of the eye from the orbital cavity.
Full Definition
Proptosis is the anterior displacement or protrusion of the eyeball from the orbit, measured as increased distance from the corneal apex to the lateral orbital rim. In craniofacial surgery contexts, proptosis often results from shallow orbits in craniosynostosis syndromes, orbital fractures with volume loss, or space-occupying lesions. The condition can be unilateral or bilateral and may cause functional problems including corneal exposure, diplopia, and visual field defects. Treatment depends on the underlying cause and may involve orbital reconstruction, volume augmentation, or canthal repositioning procedures.
Usage
Usage note: Specify measurement values and underlying etiology; distinguish from exorbitism.
In Context
- "Post-traumatic proptosis was measured at 3mm beyond normal limits using Hertel exophthalmometry." — Oculoplastic assessment
- "The syndromic patient's bilateral proptosis improved following fronto-orbital advancement." — Post-operative evaluation