What is a Cataract?
- Any opacity of the normally clear ocular lens constitutes a
cataract
- Occurring in varying degrees and forms, cataracts commonly cause
blurred or hazy vision, double vision or troublesome glare at night
- Cataracts may be caused by a multitude of conditions including
eye diseases, systemic diseases, heredity and trauma, but by far the
majority occur as part of the normal ageing process in people above
the age of 55 years. There is no known method of preventing or reversing
cataract formation
- Cataracts are diagnosed through comprehensive ophthalmic examination
and are not to be confused with the more obvious superficial growth
on the eye surface, the so-called pterygium
- Cataracts are usually slowly progressive and surgical removal
is the only treatment and is recommended once normal daily activities
are impaired
Cataract Surgery
- Microsurgical removal of the cataract is done under general or,
more often, local anaesthetic. The cataract is removed via a small incision
using ultrasound (SONAR) or mechanical instrumentation. An artificial
lens is normally implanted and the incision may be closed with very delicate
sutures, which may or may not be removed in time. Currently, the latest
techniques requiring no sutures, are preferred whenever possible.
Pre- and Postoperative Instructions
- Optimal general condition pre-operatively is important. Any infection
(of the eye, bladder, respiratory tract) or septic wounds pose a risk
to the operated eye and should first be treated. Systemic conditions
such as diabetes, hypertension, heart failure and asthema should be
well controlled. A timely visit to your general practitioner a week
in advance of surgery is advisable.
- Please discontinue all eye cosmetics and contact lenses 72 hours
prior to surgery. Anticoagulants (e.g. Disprin, Warfarin) should not
be discontinued, but coagulation status should be monitored and optimalised.
- Eye drops prescribed after the operation should be instilled by
pulling the lower lid away from the eye as follows: One drop 4 hourly
for seven days and as directed thereafter only during waking ours
(06:00-22:00). Wash hands with soap and water before administering
drops. Do not buy additional drops unless prescribed. The eye may
be left open indoors, but protect with an eye pad from windy and dusty
conditions and cover with a plastic eye shield during sleep for the
first week.
- Prevent water from entering the eye for the first week. (Do not
swim or shower)
- Pain tablets are only for the first two days after the operation.
Any subsequent lasting PAIN, REDNESS or DIMMING of VISION should be
reported to your ophthalmologist promptly. This is most important.
- Acquisition of glasses will be arranged during the last post-operative
visit.
- Occasionally, vision may dim slowly weeks to years after the operation.
It may be necessary to clear opacification of residual lens membrane
with laser as an out patient procedure requiring only a few minutes
and no anaesthetic.
What is Laser Surgery?
Myopic or short-sighted patients, as well as far-sighted patients, often
have a life long dependency on spectacles and/or contact lenses. For various
reasons these patients may wish to dispose of their spectacles and contact
lenses.
- Lasik surgery is a short operation whereby the cornea (window
of the eye) is dissected with a special keratome (cutting instrument)
and then modified/remodelled with laser.
- The laser ablation is individualised for each patient by the doctor
and controlled by computer, according to internationalized statistical
standards.
To be eligible for the treatment you should:
- Be at least 17 years old, with a refraction having remained stable
for at least one year (there is no maximum age, but presbyopia –
a condition that many times requires bifocals in patients over 40 years
of age – should be considered)
- Have no active eye disease
- Be in good health
Risks of Lasik:
- Lasik is entirely an elective procedure. As with any medical
procedure there are risks involved.
- Lasik cannot always produce 20/20 or even 20/40 vision. Lasik
does not correct presbyopia – a condition that many times requires
bifocals in patients over 40 years of age. After Lasik, some patients
may require reading glasses for close up work.
Complications:
- Infection – extremely rare.
- Lasik patients may suffer from night vision effects, similar
to htose experienced with contact lenses.
- Transient corneal haze. (3-4%). Less in lower ranges of correction.
(Virtually non-existent with Lasik).
- Significant regression (3-4%). Usually the same group as the
corneal haze. Usually responds well to re-treatment.
- Long term stability. Refraction changes after 6 months tend
to be small and to approach a final value in an asymptomatic fashion.
- Some patients complain of a dry eye, light sensitivity, blurry
vision at times. This will resolve as the eye heals. Artificial tear
supplements are used routinely after Lasik for one to six months.
- In some rare cases it may be necessary for a re-treatment, typically
6 weeks to 6 months after the initial procedure.
Preparing for Laser Surgery:
- Soft contact lens wear should be stopped at least 3 days prior
to surgery.
- 4-6 weeks prior to consultation, hard contact lens wearers will
be required to remove lenses and wear soft contact lenses or glasses for
this period.
- 3 days prior to surgery wearing of all cosmetics should be stopped.
Even with the utmost care taken when removing make-up, fine particles
are still left and can be seen under magnification.
- On the day of the surgery, dress warmly as it is very cold inside
the theatre.
Post-operative Care:
- On the day of surgery, take your medication as directed. You may
bath, but you MAY NOT wash your hair.
- See your ophthalmologist the day after surgery as directed and DO
NOT remove eye patches prior to the consultation. Continue with drops
as directed.
- DO NOT wear any make-up for the first week after surgery
- DO NOT rub your eyes.
- DO NOT play any contact sport for the 2 weeks after surgery, and
wear protective glasses for a few weeks after surgery.
- Take care when washing your face and hair for one week after surgery
to avoid getting soap in your eyes.
- Avoid swimming for 4 weeks after surgery.
- A pterygium is a superficial growth, normally slowly advancing from
the conjunctiva (white of the eye) onto the cornea (the clear tissue
over the coloured iris).
- Pterygiums are often confused with cataracts, but have no resemblance
to cataracts, which are opacities in the lens of the eye. They should
however, be differentiated from other superficial growths which may
be benign or malignant.
- The only proven cause of pterygiums is exposure to ultra-violet
light, which damages superficial tissue. Pterygiums could be regarded
as scar tissue formation in response to this damage.
- Pterygiums normally progress slowly towards the centre of the eye,
but may take many years before actually threatening sight.
- Pterygiums occur in all age groups and are more common in people
spending much time outdoors. They may be asymptomatic or, when more
advanced, cause itching, burning, grittiness and redness. There is
a frequent association with poor tear function.
- Small symptomatic pterygiums are often managed satisfactorily with
short courses of cortisone drops and artificial tear supplements.
Surgery is considered when conservative treatment fails or when pterygiums
are cosmetically unacceptable or sight threatening.
- Surgical removal of a pterygium is a relatively low risk operation
as it is limited to the surface of the eye. However, considerable
discomfort is experienced post-operatively by most patients. Pterygiums
have a very strong tendency to recur. Any one of a number of preventative
techniques to curb recurrences may be routinely employed at the time
of surgery.
- Keeping the eye closed for the first 10-14 days after the operation
usually makes it more comfortable. Dust, water, shampoo and other
foreign matter should be avoided. Drops are applied 4 times per day
for the first 2 weeks. The eye usually remains conspicuously red for
a few weeks and then returns to a normal white appearance after 6-8
weeks.
- Diabetes mellitus affects the eye through premature cataract formation,
fluctuating refraction (spectacle requirements) and so called retinopathy.
Retinopathy implies malfunction of the nerve and sensory layer of
the eye due to damaged small blood vessels and manifests in three
basic forms:
i. early background changes which seldom affect vision and are relatively
innocuous.
ii. maculopathy which impairs vision.
iii. proliferative retinopathy, the complications of which may have
catastrophical visual consequences.
- Optimal control of diabetes through diet, oral medication or insulin
injection is very important and may delay, but not necessarily prevent
the onset of retinopathy.
- Systemic hypertension (high blood pressure) should be well controlled,
as should high blood cholesterol levels.
- Complete ophthalmic evaluation shortly after the initial diagnosis
of diabetes is advised. Depending on the findings at this stage, regular
follow-up visits will be scheduled to monitor progression. Since treatment
may be required in the presence of absolutely normal vision, these
follow up examinations are most important.
- Once vision threatening retinopathy is noted, different forms of
laser treatment are employed to improve vision or prevent further
complications.
- Some of these complications (e.g. vitreous haemorrhage, membrane
formation or retinal detachment) may require surgical treatment.
- The keys to preservation of vision are:
a. early base line evaluation.
b. regular follow-up examination (as scheduled or promptly when new
symptoms appear) to monitor any progression.
c. optimal control of the diabetes.
Dry eyes or so-called keratoconjunctivitis sicca is a common condition
affecting patients of all ages. Although not a disease, it represents
poor tear function caused by disfunction of one or more of the components
of tear production and/or dynamics.
The lids play a key role because of:
a) their blinking action and
b) the oil glands contained in the eye lids, which are responsible for
the critical oily component of a normal tear film.
Burning or a gritty feeling of the eyes, often accompanied by episodes
of tearing are the most common symptoms. Associated heaviness of the
eyelids and a precipitate or even frank discharge upon waking is common.
Intermittent blurring of vision and even episodic double vision may
occur.
The corner stone of therapy is the frequent use of artificial tear
supplements. Initially very frequent applications may be called for,
but as the eye surface recovers, symptoms may be controlled by applying
drops two to three times per day. The eyelids are often affected by
so called seborrheic eczema, for which scrubbing of the eyelid margin
with baby shampoo, morning and evening, is necessary. Depending on the
condition of the eye and lids, a short course of antibiotics and cortisone
drops may be used. If poor oil gland function is prominent a low dose
of oral antibiotics for plus minus four weeks is often recommended.
Although the condition cannot be cured, symptoms may be dramatically
relieved by the above measures. Aggravating circumstances, for instance
wind, heat, air conditioning or extended periods of reading or watching
TV and the use of soft contact lenses can be avoided or otherwise attenuated
by timely and frequent use of artificial tear supplements.
*Plugging of the tear ducts may further reduce the need for tear supplements.
EYELID HYGIENE (if so directed by doctor):
*1 drop Johnson’s baby shampoo and 1 tablespoon warm tap water.
(mix in egg cup)
* Scrub eyelid margins (above and below) thoroughly with a cotton bud
soaked in the
above solution. Repeat morning and evening.
- This is a vast topic and only the most common forms of squint in
young children are referred to briefly. A squint or strabismus may
be primary (the most common kind) or secondary to an underlying cause.
- ANY squint, whether constant or intermittent, occurring in a child
after the age of three months, should always be properly assessed
by an eye specialist.
- The eye specialist’s first task is to exclude underlying (sometimes
serious) causes of strabismus. These may include congenital conditions,
rare neurological syndromes, brain tumors, birth injuries and localized
eye diseases. Fortunately these causes of strabismus are by far the
minority.
- Secondly, it is of paramount importance to ascertain whether the
young child’s vision is normal and equal in both eyes. Poor
vision in one eye may cause a squint. Equally important is the fact
that an otherwise normal eye may loose visual ability and become lazy
or amblyopic, because of a squint. This danger exists until the age
of roughly 9 years.
- If it is diagnosed early, an amblyopic eye may be stimulated with
reasonable success to improve and normalise visual ability. After
the age of about 9 years visual ability is permanently fixed and can
not be manipulated.
- All the above information can only be obtained by thorough and sometimes
repeated ophthalmic examination, which may even require examination
under anaesthetic.
- A dilated examination of the eye and cycloplegic refraction (having
enlarged the pupils with eye drops) is an essential part of such an
assessment. If a significant refractive error (spectacle error) is
present, its causative role should be assessed by a trial period of
wearing the appropriate spectacles. A purely refractive accommodative
squint will be eliminated by the spectacles alone.
- In a second group of children the spectacles may reduce but not
eliminate the squint. If the residual squint is significant it may
be surgically corrected. After surgery the use of spectacles will
still remain essential.
- In a third group of children a refractive error is not relevant
and surgical repair alone should eliminate the squint.
- Although squints are often referred to as being left or right sided,
a squint involves misalignment of BOTH eyes and surgical repair is
seldom attempted before BOTH eyes have equal and normal visual ability.
Likewise, strabismus surgery is often done on both eyes, whether at
one or more than one session.
- Even after successful surgical or other correction of strabismus
the danger of amblyopia remains until the age of approximately 9 years
and regular follow up visits should be made regardless of a good cosmetic
result.
- This condition occurs commonly in people over 60 years of age and
is one of the most common causes of poor vision in elderly Europeans.
- Lining the inside of the eyes is the retina, which is a photo sensitive
layer comparable to a photographic film. A tiny 5mm diameter part
of the retina, called the macula, is responsible for sharp visual
acuity and colour vision.
- Several degenerative processes may affect the macula. In the case
of age related macular degeneration, increasing age is the main causative
factor.
- The degeneration involves weakening of certain supportive layers
in the macula and the accumulation of metabolic waste products. These
yellowish white deposits resemble calcification and are often referred
to as such.
- The most common complication is the development of new, abnormal
blood vessels which are fragile and easily leak and bleed (so-called
neovascular membranes).
- The early symptoms of macular degeneration are deterioration of
visual acuity and distortion of images. AT WORST complete loss of
central vision may occur, with the patient seeing a dark spot central
to the visual field.
- Darkness and light and forms may still be well differentiated and
a measure of colour vision may be retained. Both eyes are usually
affected, one eye typically more advanced that the other.
- Unfortunately reading, sewing and other tasks requiring sharp visual
acuity, become impossible.
- On the other hand macular degeneration per se never causes total
blindness and patients often function well and independently within
familiar surroundings. Unfortunately driving a motor vehicle is mostly
not possible.
- Therapeutic options available to treat this condition are very limited.
Neither spectacles nor surgery or medication can stop the degeneration.
- Neovascular membranes may under certain circumstances be treated
with laser. Surgical removal of these membranes is being done in selected
cases with limited success.
- Generally vision is monitored with a Amsler chart and sudden significant
changes in visual acuity and/or distortion on the Amsler chart call
for evaluation and possible treatment by an eye specialist. Spectacles
and so called low vision aids (including various magnifiers) are also
of some value.
- Lastly, it is important to note that age is virtually the only causative
factor and no amount of reading, sewing or other activities add to
this.
- Once this condition has been diagnosed, it is equally important
to note that there is no limitation to the use of your eyes and you
should confidently engage in any activity your eye allows.
- Glaucoma is an eye disease characterised by typical optic nerve
damage and concomitant visual field loss.
- The most common form of glaucoma, Primary Open Angle Glaucoma,
occurs mainly in persons 40 years of age and older. It tends to run in
families, is more common in diabetics and nearsighted individuals and
is characterised by increased intra ocular pressure. Other forms of glaucoma
may be congenital or secondary to inflammation, injury or other diseases
of the eye.
- Glaucoma normally develops insidiously without early signs or
symptoms. Slowly progressive damage may only manifest much later as loss
of peripheral or even central vision. On the contrary, the much less common
Acute Angle Closure Glaucoma is normally diagnosed early due to sudden
onset of blurred vision, pain, redness and sometimes nausea.
- Glaucoma is best diagnosed or ruled out by thorough ophthlmological
examination, particularly after age 40 and especially in the presence
of nearsightedness, diabetes or a family history of glaucoma.
- If treated early and effectively, glaucomatous visual loss may
be limited or halted. Initial treatment normally involves eye drops. Inadequate
control may necessitate laser treatment or eventually surgical treatment.
- Visual loss from glaucoma is usually irreversible and permanent.
As timely medical or surgical intervention may effectively preserve vision,
early and regular eye examination is most important.
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