Blow out # orbit is characterized by
A. DiplopiaB. Tear drop sign
C. Forced duction test
D. Exophthalmos
E. All of above
The Answer is. (A) Diplopia; (B) “Tear drop” sign ;
(C) Forced duction test
Orbital blow-out fractures
are usually the result of a direct blow to the orbit. This results in a sudden
increase in the intra-orbital pressure which in turn causes decompression by
fracture of one or more of the bounding walls of the orbit.
Associated clinical
findings may include:
Enophthalmos - due to
increased orbital volume
Diplopia - due to
extra-ocular muscle entrapment
Orbital emphysema -
especially when fracture is into an adjacent paranasal sinus
Malar region numbness - due
to injury to the inferior orbital nerve
Blow-out fractures can
occur through one or more of the walls of the orbit:
1.
Inferior (floor): most common, usually associated with medial wall #.
In
children: trapdoor fracture (fracture bone springs back to place)
2.
Medial wall (lamina papyracea): prolapse of orbital fat into ethmoid
air space is typical
3.
Superior (roof): uncommon, associated with CSF leaks and meningitis
4.
Lateral wall (rare)
Signs:
Orbital emphysema: black
eyebrow sign
Herniation of orbital fat
inferiorly: tear drop sign
It is recommended to perform the forced
duction test under sedation, local, or general anesthesia: to check for entrapment of the soft tissues,
in case extra ocular muscles are not functioning
