4. Examine the patient to check the extraocular muscle (EOM) are functioning properly.
5. If the extraocularmuscles(EOM) are notfunctioning properlythe surgeonshouldmake sure thatthere
isno entrapmentof the softtissues.Itisrecommendedtoperformthe forcedductiontestunder
sedation,local,orgeneral anesthesia.
7. and below to evaluate facial symmetry.
The illustration on the right shows a posttraumatic asymmetry of globe protrusion (left
enophthalmos).
8. Hertel exophthalmometer
This instrument is only reliable to measure the sagittal globe position correctly in a side-to-side
comparison if the lateral orbital rim is intact and not displaced. In these cases, the amount of en-
or exophthalmos can reliably be measured.
Note: Evaluation for enophthalmos in the acute setting is unreliable because of orbital edema.
9. Naugleexophthalmometer
In case of acquiredorcongential asymmetryof the lateral orbital rimsaHertel exophthalmometeris
misleading(see above).Inthese cases,aNaugle exophthalmometerispreferredsincethe referring
structure isnot the lateral orbital rimbut the frontal andinfraorbital structures
11. Relative afferent pupillarydefect(RAPD)
Witha lightmovingfromone pupil tothe other,a relative afferentpupillarydefectcanbe detected.In
the consciousor unconsciouspatientwhohasnodrug-relatedcompromise of pupillaryfunction,this
testprovidesareliable assessmentof whetherornot an afferentdisorderof the visual systemis
present.
Whenneitherthe RAPDnorthe pupillaryreactiontestcanbe performed,aVisual evokedpotential
(VEP) maybe appropriate.
12. The illustration shows the optic nerve with impingement of the optic nerve at the orbital apex.
There is no indirect light reaction of the unaffected right eye (Marcus Gunn pupil).
Note: The indirect light reaction is more reliable than the direct pupillary reaction to detect
posttraumatic optic nerve lesions.