water. However, medical attention is
needed if the object has penetrated the
eyeball. Dropping the dye fluorescein
into the eye reveals corneal abrasions
or sites of penetration. Ultrasound scan-
ningor an X-rayof the eye may also be
performed. Local anaesthetic eye-drops
may be applied and a spatula used to
remove an object from the cornea. The
eye may then be covered with a patch.
Antibiotic drugsmay also be prescribed.
eye injuriesSerious eye injuries may
be caused either by penetration of the
eyeby a foreign body (see eye, foreign
body in) or by a blow to the eye.
A blow to the eye may cause tearing of
the irisor the sclera, with collapse of
the eyeball and possible blindness.
Lesser injuries may lead to a vitreous
haemorrhage, hyphaema, retinal detach-
ment, or injury to the trabeculum (the
channel through which fluid drains from
inside the eye), which can lead to
glaucoma. Injuries to the centre of the
corneaimpair vision by causing scar-
ring. Damage to the lensmay cause a
cataractto form.
eyelashes, disorders ofThe eyelash-
es are arranged in two rows at the front
edge of the lid and normally curve out-
wards. Growth in an abnormal direction
may be due to injury to the lid or, more
commonly, to infection. Severe blephar-
itismay destroy the roots of the lashes.
Trachoma, an infection in which the lid
is distorted by scarring, may lead to
trichiasis. With age, the lashes become
finer and fewer.
eye, lazyA popular term for amblyopia
or a convergent squint.
eyelidA fold of tissue at the upper or
lower edge of an eye socket. The eyelids
are held in place by ligamentsattached
to the socket’s bony edges. They consist
of thin plates of fibrous tissue (called
tarsal plates) covered by muscle and a
thin layer of skin. The inner layer is cov-
ered by an extension of the conjunctiva.
Along the edge of each lid are two rows
of eyelashes. Immediately behind the
eyelashes are the openings of the ducts
leading from the meibomian glands,
which secrete the oily part of the tear
film. The lids act as protective shutters,
closing as a reflex action if anything
approaches the eye. They also smear
the tear film across the cornea.
eyelid, droopingSee ptosis.
eyelid surgerySee blepharoplasty.
eye, painful redA common combina-
tion of eye symptoms that may be due
to any of several eye disorders.
Uveitisis a common cause of dull,
aching pain. The redness is caused by
widening of blood vessels around the
iris. Another serious cause of pain and
redness in one eye is acute closed-
angle glaucoma. Other causes include
keratitis, usually due to a corneal ulcer,
or a foreign body in the eye (see eye,
foreign body in). The most common
cause of redness and irritation in the
eye is conjunctivitis.
eye-strainA common term for aching
or discomfort in or around the eye. This
is usually due to a headache caused by
fatigue, tiredness of muscles around
the eye, sinusitis, blepharitis(inflamma-
tion of the eyelids), or conjunctivitis.
eye teethA common name for canine
teeth.
eye tumoursTumoursof the eye are
rare. When eye tumours do occur, they
are usually cancerous and painless.
Retinoblastomais a cancerous tumour
of the retinathat occurs in one or both
eyes and most often affects children. It
may be treated by radiotherapy, laser
treatment, or cryosurgery, but the eye
may have to be removed to prevent
spread of the tumour.
Malignant melanomais a cancer of the
choroid. It usually affects older people.
There are no symptoms in the early
stages, but it eventually causes retinal
detachmentand distortion of vision.
Small tumours can be treated by laser,
but the eye may need to be removed to
avoid spread of the tumour.
Secondary eye tumours occur when
cancer elsewhere in the body spreads to
the eye. Symptoms depend on the tu-
mour’s location and growth rate. It may
be controlled by radiotherapy.
Basal cell carcinomais the most com-
mon type of tumour affecting the eyelid.
It usually has a crusty central crater
and a rolled edge. In the early stages,
treatment may be possible by surgery,
radiotherapy, or cryosurgery.EYE INJURIES EYE TUMOURS
E