l. The lens
may be partly or completely dislocated, and in the latter case it may
pass forward into the anterior chamber or backward into the vitreous.
Among other injuries resulting from contusion of the eye may be
mentioned haemorrhage into the vitreous, rupture of the choroid, and
detachment of the retina.

Injuries in which the outer coat of the eyeball is ruptured may be
further subdivided into two groups according to whether or not a
foreign body is lodged in the globe.

Rupture of the outer coat, especially when it results from a punctured
wound, adds greatly to the risk of the injury, by opening up a path
through which infective material may enter the globe, and this risk is
materially increased when a foreign body is retained in the cavity of
the eyeball.

When the globe is burst by a blow with a blunt object, the sclerotic
usually gives way, and as the rupture takes place from within outward,
there is less risk of infection than in punctured wounds. The lens may
be extruded through the wound, and the iris prolapsed. If the rupture
is large, the conjunctiva torn, and the globe collapsed from loss of
vitreous, the eye should be removed without delay. If sight is not
entirely lost and there is no marked collapse of the globe, an attempt
should be made to save the eye.

Wounds produced by stabs or punctures are liable to be followed by
infective complications ending in panophthalmitis. When this is
threatened, removal of the eye is indicated, not only because the
affected eye is destroyed beyond hope of recovery, but to avoid the
risk of "sympathetic ophthalmia" affecting the other eye.

#Orbital Cellulitis.#--Infection of the cellular tissue of the orbit
by pyogenic bacteria is specially liable to follow punctured wounds
and compound fractures, if a foreign body has lodged in the orbital
cavity. It may also result from the spread of a suppurative process
from the globe of the eye, the conjunctiva, or the nasal fossae or
their accessory air sinuses. Both orbits may be affected
simultaneously.

_Clinical Features._--The disease is ushered in by rigors, high
temperature, and severe pain, which radiates all over the affected
side of the head. There is exophthalmos and fixation of the globe,
with redness, swelling and tenderness of the eyelids, and congestion
and ecchymosis of the conjunctiva. The pupil is usually dilated, the
cornea becomes opaque and may ulcerate, and there is photophobia and
sometimes dipl