fissure

(redirected from orbital fissure)
Also found in: Dictionary, Thesaurus, Medical.
Related to orbital fissure: orbital fossa, orbital gyri, orbital foramen

fissure

1. Anatomy a narrow split or groove that divides an organ such as the brain, lung, or liver into lobes
2. a small unnatural crack in the skin or mucous membrane, as between the toes or at the anus
3. a minute crack in the surface of a tooth, caused by imperfect joining of enamel during development
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

fissure

[′fish·ər]
(geology)
A high, narrow cave passageway.
An extensive crack in a rock.
(metallurgy)
A small cracklike discontinuity with a slight opening or displacement of the fracture surfaces.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
distance between the base of the superior orbital fissure and Warwick's foramen.
Traumatic superior orbital fissure syndrome: Review of literature and report of three cases.
THS is caused by a non-specific inflammatory process in the cavernous sinus or superior orbital fissure (SOF).
Specific diagnostic criteria have been recommended by the International Headache Society which includes unilateral headache; granulomatous inflammation of the cavernous sinus and superior orbital fissure or orbit seen on magnetic resonance imaging or biopsy; paresis of one or more of the ipsilateral third, fourth, and/or sixth cranial nerves; evidence of causation demonstrated by both headache preceded by oculomotor paresis by less than 2 weeks or developed with it and headache that is localized around the ipsilateral brow and eye; and symptoms not better accounted for by an alternative diagnosis [9].
OM may cause infections of cavernous sinus, but the infections of cavernous sinuses, superior orbital fissure or orbital apex are usually originated from para-nasal sinuses.4 Time interval between the onset of OM and cranial nerve involvements is usually between 1 week to 2-3 months.5
The intracranial extension has been described through the three major openings in the posterior aspect of the orbit, which include the superior orbital fissure, optic canal and the inferior orbital fissure.
From the superior orbital fissure, light could travel through the cerebrospinal fluid behind the lesser wing of the sphenoid andalong the edge of the sella turcica will go directly into the mesencephalon (Figure 4(a)).
It was directed outwards, whereas in the posterior part of the orbital floor (between the inferior orbital fissure and the optic nerve canal) the area of relocation extended as far as 0.5 mm and was directed towards the inside of the orbit, "the recurring wave" (white arrow, Figure 3).
The lesion can involve any peripheral nerve but usually involves sensory nerves in the orbit or eyelid and can cause widening of the superior orbital fissure as well as dysplasia of the greater sphenoid wing [63].
This formation separates optic canal from the medial portion of superior orbital fissure. Position of the optic strut was determined based on relation between the length of anterior clinoid process and the distance measuring from the optic strut to the top of the anterior clinoid process.
Tolosa-Hunt syndrome (THS) is a rare disorder indicated by recurrent painful ophthalmoplegia caused by non-specific inflammation of the cavernous sinus or superior orbital fissure (SOF).
Typically, a fracture line extends from the inferior orbital fissure anteromedially along the orbital process of the maxilla, toward the infraorbital rim.