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					Glaucoma
the silent theft of sight




Risk
Ocular pressure
How to recognise it
Treatment
Laser surgery
Glaucoma surgery
Recommendations




www.eugs.org
   Questions
       &
    Answers
                         WHAT TO DO                          3	 follow the treatment as prescribed
                                                             3	 have regular medical examinations
                                                             3	 inform your eye specialist if you are suffering
                                                             from any general disease such as asthma, allergies,
                                                             kidney stones, cardiac arrhythmias, diabetes, arterial
                                                             hypotension or hypertension
                WHAT NOT TO DO
                                                             3	 change your Glaucoma medications without first
                                                             consulting your doctor
                                                             3	 skip the medication even if you have missed the
                                                             time of your usual dose
                                                             3	 interrupt the treatment
                                                             3	 fail to go for planned medical examinations

      ADVICE FOR RELATIVES
                                                             3	 do not be afraid that it may be contagious,
                                                             because glaucoma is not an infectious disease
                                                             3	 arrange regular eye examinations because most
                                                             forms are more common among close relatives.

REmEmbER THAT                                                                      notes
3	A complete eye examination is a lot more
more than a simple eyesight test
3	Damage from many eye diseases usually goes
undetected until it is too late
3	Only an eye specialist can recognise the early
signs of eye diseases before their manifestation
3	A great opportunity for a complete eye
examination is at the onset of presbyopia (far-
sightedness), usually between forty and fifty
years of age.

  Sometimes popular lay magazines contain information on new treatments that promise miracles. Often the
  reported news has some sound basis but it is important to remember that in matters of health there are
  large economic interests at stake, which may influence the nature of the information described. The aim of
  this magazine is to provide patients with general medical information. Those concerned should consult an
  eye specialist/ophthalmologist, the only professional capable of recommending the most adequate course of
  action for each case and knowledgeable about what can be realistically expected from adequate management.
  Should the eye specialist consulted not be personally trained in a specific area, he/she will certainly be able to
  recommend an experienced and reliable colleague.
Glaucoma                                                             GLOSSARY


                    summary
                                                            W h at does
                                                            it mean...?
The eye: a camera
                                                            Acute: sudden
pag. 4     Visual function                                  Eyeball: eye
                                                            Visual field: the whole that we
Ocular pressure                                             can see without moving our
                                                            gaze
pag. 5    Intraocular pressure (IOP)                        Conjunctiva: membrane lining
pag. 5    Where does the aqueous humour drain to?           the eyeball
pag. 5    What is glaucoma?                                 Chronic: persistent
                                                            Drainage: discharge
Glaucoma                                                    Fluid: liquid
                                                            Incisional: carried out by
pag. 6    How many different types of glaucoma are there?   surgical cut
pag. 7    How is glaucoma diagnosed?                        Low vision: very poor visual
                                                            performance
How to recognise it                                         Iridotomy: tiny hole in the iris
                                                            Ophthalmologist: physician
pag. 8    Tonometry
                                                            specifically trained to diagnose
pag. 8    Gonioscopy
                                                            and treat eye diseases
pag. 8    Ophthalmoscopy
                                                            Monitor: measure at different
pag. 8    Perimetry
                                                            times
Treatments                                                  Optic nerve: ”cable” carrying
                                                            images from the retina to the
pag. 9    Medications                                       brain
                                                            Papilla: connecting point of the
Laser treatment                                             optic nerve to the eyeball
                                                            Intraocular pressure (IOP):
pag. 10   Yag laser iridotomy                               internal pressure filling the
pag. 11   Argon laser trabeculoplasty                       eyeball
                                                            Scotoma: “blind” spot in the
Glaucoma surgery                                            visual field
                                                            Aqueous humour: watery fluid
pag. 13   Trabeculectomy                                    that fills the chambers of the
                                                            eye and carries nutrients
Useful recommendations                                      Trabeculum: spongy filter from
                                                            which the aqueous humour
pag. 14   Questions & Answers
                                                            escapes
           The eye:
           a camera                                                     The visual function


    The eye works as a camera;        to admit more or less light.        the retina, thus generating
    it has lenses, a diaphragm        Thanks to the cornea and the        the visual stimuli. The visual
    and a film. The cornea            crystalline lens (lenses), the      stimuli are then transformed
    e and the crystalline lens        image is sharply focused on         into electrical impulses and
    are the parts that function       the retina (film). The retina       carried through the optic
    as focusing lenses. Between       lines the posterior chamber         nerve to the brain, which
    them we find the iris, the        of the eye, which is filled         interprets them by shaping
    coloured part of the eye          with a gelatinous substance         the images.
    that varies from person           known as “vitreous body”.           Any alteration affecting one
    to person. At the centre of       Light passes through the            or more of these parts results
    the iris there is the pupil       cornea, pupil, crystalline lens     in a defective perception of
    (diaphragm), which adjusts        and vitreous body and hits          the images.


                                                    eye

                                                                optiC
                                     retina                     nerve
                                                                head

                       Crystalline
                          lens

                    iris
           Cornea




                                                                               Camera


                                                              Film

                                                   2nd lens

                                           diaphragm
                                      1 lens
                                      st

          Ocular
          pressure                                                                   What is the
                                                                                aqueous humour?

Intraocular pressure (IOP)              pupil; the drainage channels            nerve is similar to a transmission

The eye behaves like a semi-
                                        of the aqueous humour are               cable connecting the retina to the
                                        just next to the internal angle         brain and is composed of a bundle
elastic ball filled with constantly     between the cornea and the              of filaments known as “nerve
circulating fluids. If the amount       anterior face of the iris.              fibres”: more than a million for
of fluid produced does not equal                                                each eye. The point where this
the amount reabsorbed, there is a                                               cable connects to the rear part of
fluid surplus. Just like in a balloon                                           the eye is known as the “papilla”
that is too inflated, this causes an                                            or optic nerve head. The health
increase in the internal pressure.                                              of the papilla depends on the
Thus, the internal pressure of                                                  circulation of blood and nutrients.
the eye, or intraocular pressure,                                               fig. 1
corresponds to the tension of
the eyeball.
The fluid flowing inside the eye,
which is responsible for the
                                        The drainage channels of the
intraocular pressure, is known
                                        aqueous humour are located just
as the “aqueous humour”.                next to the angle between the
                                                                                fig. 2
                                        cornea and the iris, where the filter
                                        known as “trabeculum” is positioned.
                                        Obviously, they are not visible
                                        with the naked eye but may
                             Normal     be compared to a microscopic
                          Damaged       filter located right at the
                                        bottom of the angle, in a sort
                                        of drainpipe, beyond which              The papilla (Fig. 1) is the point
                                                                                crossed by optic nerve fibres. In
                                        the drainage channels direct            the presence of glaucoma (Fig. 2)
                                        the flow through the wall of            the fibres atrophy and the edge of
An excessively high intraocular         the eyeball where the fluids            the papilla becomes thin.
pressure damages the optic nerve        are reabsorbed. The aqueous             This is slowed down and
more visibly at the point where it      humour, in fact, has nothing to         inhibited when the ocular
connects with the eyeball (papilla
or optic nerve head)                    do with the formation of tears.         pressure becomes too high. Each
                                                                                fibre of the optic nerve carries a
Where does the aqueous                  What is glaucoma?                       part of the visual message from

                                        Glaucoma is a disorder of the
humour drain to?                                                                the retina to the brain, where

The aqueous humour is
                                                                                the images of our surroundings
                                        optic nerve, which is usually           are formed. The “visual field”
produced behind the iris and            damaged by excessively high             is the whole image that we can
flows forward through the               intraocular pressure. The optic         see without shifting our gaze.
                                                                                                                      
               Glaucoma
                                                                                        Causes and effects


    When, because of glaucoma, the            already extensive damage to the           without any symptoms affect vision,
    fibres of the optic nerve become          optic nerve. In the meantime, the         to the point where it causes serious
    damaged, some areas known as              patient will continue to see clearly      damage before being detected.
    “scotomas”, where it is no longer         at the centre. In the final phases the    In some cases the glaucomatous
    possible to see, appear within the        optic nerve is completely destroyed       damage progresses in spite of the
    visual field. Initially very small, the   and blindness occurs. It is for this      fact that the intraocular pressure
    scotomas are noticed only when            reason that it is essential to diagnose   remains within apparently normal
    they become bigger and there is           the glaucoma as early as possible.        limits. The treatment of these cases
                                    Initial
                                                                                        of “normal-pressure glaucoma”
                                 scotoma      How many different types of               can be difficult.
                                              glaucoma are there?                        2) Closed-angle Glaucoma
                                                                                         Trabeculum
                                              1) Chronic open-angle glaucoma
                                               Trabeculum



                               The width                                                                        Iris
                                   of the
                                scotomas
                                                                      Iris              Closed-angle glaucoma is the result
                                increases
                                                                                        of an obstruction in the angle,
                                              This type of glaucoma, also known         which closes as if a sheet of paper
                                              as primary open-angle glaucoma,           floating in a sink were to rest on
                                              is the most common form of                the plug-hole and block it. In the
                                    Very
                                              glaucoma and is associated with           eye it is the iris that can act as such
                                  serious
                                              a kind of ageing of the drainage          sheet of paper, which can be sucked
                               damages;       filter: the capacity to reabsorb the      against the cornea and completely
                             with central     aqueous humour decreases with             block the passage of the aqueous
                                 tubular      increasing age and the pressure           humour towards the angle. This
                                   vision     within the eye gradually increases.       usually occurs gradually, but if this
                                              We are talking about glaucoma             closure is sudden, we are dealing
                                              when, because of the high                 with an “acute attack” of glaucoma.
                                              pressure within the eye, the optic        The latter is accompanied by clear
                             Pre-terminal
                                damages;
                                              nerve becomes damaged and as              symptoms, which usually prompt the
                            only a lateral
                                              a consequence the visual field is         patient to see an ophthalmologist,
                                  residue     also damaged. More than 60% of            with great urgency. These symptoms
                                  persists    glaucomas in adults are of this           may include:
                                              type. Unfortunately, this form               Vision of coloured halos
                                              of glaucoma may gradually and                around lights.

           Type                         Causes                     effeCTs                 CommenTs
        Chronic                Slow obstruction of    Slow reduction in                This type of glaucoma
                               the drainage channels. peripheral vision                is chronic and
      open-angle               Slow increase in                                        advances very slowly
       glaucoma                ocular pressure

    Acute attack               Total blockage of the       Coloured halos, ocular      Severe damage can
                               drainage channels           pain, cloudy vision,        rapidly occur in the
   of closed-angle             The pressure suddenly       headache, often             absence of adequate
      glaucoma                 increases                   nausea and vomiting         and immediate
                                                                                       treatment

       Secondary               Traumas, infections, Slow reduction in                  This type of glaucoma
                               tumours, medications peripheral vision                  may advance very
       glaucoma                or inflammation                                         slowly just like chronic
                               damage the drainage                                     open-angle glaucoma
                               channels

      Congenital               Abnormal drainage           Very big eyes               This condition should
                               channels from birth         Opaque cornea               be treated at birth by
      glaucoma                                             Hypersensitivity to         experts in this type of
                                                           light                       glaucoma
                                                           Excessive watering

   Ocular pain.                            Opacity of the cornea.               can reliably measure the ocular
   Cloudy/hazy vision.                     Excessive eye-watering               pressure, is trained and authorised
   Headache.                               Sensitivity to light                 to use the appropriate instruments
   Nausea and vomiting.                    (photophobia)                        and, above all, is capable of
3) Secondary glaucoma                                                           assessing the presence of other
Secondary glaucoma results               How is glaucoma diagnosed?             important diagnostic signs or

                                         The most common type of
from specific causes, such as                                                   identifying relevant risk factors.
traumas of the eye, medications,                                                Not all the tests are essential at
intraocular tumours, inflammation        glaucoma occurs in adulthood           each examination and for each
and circulatory disorders. The           and is more common in the              patient, although some should be
ocular pressure increases because        elderly. It is usually asymptomatic,   repeated at regular intervals to
the drainage system of the fluids        therefore the diagnosis is often by    identify early signs of glaucoma
is damaged. In these cases the           chance and occurs during an eye        or to follow the evolution of any
treatment can be very complicated        examination carried out for some       damage already present:
4) Congenital glaucoma                   other reasons. For this type of           measurement of the ocular
This is a rare form of glaucoma that     glaucoma age is the most important        pressure: Tonometry
is present at birth or early infancy.    risk factor, in addition to possible      examination of the drainage
In these cases the drainage angle        hereditary factors. It is a good          angle: Gonioscopy
has a congenital abnormality. These      idea, even in the absence of any          evaluation of optic
cases, therefore, will require highly    symptom, to undergo a complete            nerve alterations:
qualified treatment. Here is what is     eye examination at least once after       Ophthalmoscopy
usually observed:                        40 years of age. Only a physician         evaluation of the visual field:
   Enlargement of the eyeball.           specialized in ophthalmology              Perimetry.
                                                                                                                      
             Glaucoma
                                                                                   How to recognise it


    What is tonometry?                    drainage angle of the eye.                to directly observe the retina and

    Tonometry is nothing more
                                          After administering a drop of local       the point where the optic nerve
                                          anaesthetic, a special contact lens is    connect to the eyeball, known as
    than the measurement of               applied to the eye. This technique,       “papilla” or “optic nerve head”.
    the ocular pressure, and              which may be performed only by            In the presence of glaucoma,
    may reliably be performed             an ophthalmologist, is completely         the damaged optic nerve
    only by an ophthalmologist.           painless and gathers important            head appears flattened by the
    After the eye is anaesthetised with   information on both the anatomy           excessive pressure, turns pale
    a drop of local anaesthetic and       of the anterior part of the eye           and shows different types of
    a yellow–orange dye is applied,       being examined and the type of            alterations, depending on the
    a small cone of plastic material      glaucoma that might be present.           individual.
    attached to the “biomicroscope” is    Lenses of the same type are used
    placed on the cornea. Illumination    to highlight the parts that are
    with a blue light optimises the       likely to be subjected to the laser
    measurement of the pressure.          treatment.
    This is a quick, absolutely
    painless test that carries no
    risks. The other instruments for
    measuring the ocular pressure are
    the indentation tonometer, the
    pneumotonometer and the non-
    contact (air puff) tonometer, but
    they are usually less precise.                                                  What is perimetry?

                                                                                    Perimetry is the technique that
                                                                                    examines the visual field.
                                                                                    It uses both computerised and
                                                                                    manual instruments and is capable
                                                                                    of assessing the sensitivity of each
                                                                                    eye to homogeneous light stimuli
                                          What is ophthalmoscopy?                   projected inside a special dome.

                                          O
                                                                                    The test usually maps out
                                               phthalmoscopy is the                 the boundaries of the field of
                                          examination of the posterior              vision where the glaucomatous
                                          structures of the eye. It is              defects called scotomas are
    What is gonioscopy?                   performed with an instrument              represented by darker than

    Go n i o s c o p y
                                          that shines a light to illuminate         normal areas, or by numerical
                           is     the     the inside of the eye. Thanks to a        values that the specialist is
    examination            of     the     system of lenses it is thus possible      then capable of interpreting.

Your                                                               Your
health                                                             medication

  Kidney stones, asthma, chronic                                     Should the times of the treatment
bronchitis, allergies and cardiac                                  not be practical, or should they
arrhythmias are among the diseases                                 interfere with your normal daily
where the use of some of the                                       activities, it is important to discuss
medications that lower the ocular                                  this with your eye specialist.
pressure may be contraindicated.
Inform your doctor before the
treatment is decided.




                                                                            of aqueous humour or improving
                                                                            its drainage. They are to be
                                                                            taken regularly and continually,
                                                                            and should not be interrupted
                                                                            without the doctor’s permission.
                                                                            Some may have unpleasant side
                                                                            effects: some of them may cause
                                                                            burning or redness of the eye,
                                                                            others may temporarily cloud
                                                                   fig. 1   the eyesight and cause headache.
                                                                            Some can also interfere with the
Perimeter: instrument used to                                               cardio-respiratory activity, and it
measure the visual field                                                    is therefore essential to inform
How c a n g l a u c o m a b e                                               the eye specialist/ophthalmologist
treated?                                                                    about any personal health problems

P   eople suffering from glaucoma
                                                                            and any other therapy one may
                                                                            be undergoing. When eye-drops
must undergo specialised                                                    alone or even a combination of
regular examinations throughout                                             them are not sufficient, tablets may
their entire life. This is because                                 fig. 2
                                                                            be prescribed in addition. These
glaucoma is a complex disease        It is important to limit the
                                                                            may also cause side effects, such
which requires more than just        damage at the start when it is still
                                     moderate (Fig. 1).                     as tingling fingers, gastrointestinal
monitoring the ocular pressure.      When the optic nerve is completely     problems and appetite loss. In
The same pressure value may          atrophic (Fig. 2) most of the visual
                                                                            people who are subject to kidney
produce different effects in         function is irreversibly lost.
                                                                            stones oral medications may cause
different patients, consequently
                                                                            a recurrence. This explains why
each person must be assessed         individually. Once the damage has
                                     occurred it is usually irreversible.   tablets are not widely used.
                                     The purpose of treatment is to
                                     prevent further worsening and it           It is estimated that around
                                     is based on the use of medication,      3% of the adult population is
                                                                             affected by glaucoma.
                                     laser treatments and surgery.           This percentage rises up to
                                                                             10% for the population over
                                     Medication                              70 years of age. In spite of
                                                                             its considerable frequency,
                                     Me d i c a t i o n  is usually
                                                                             a significant part of these
                                                                             cases is diagnosed too late.
                                     administered locally as eye-drops       In industrialised countries
                                     or gel. These substances are            glaucoma is among the three
                                                                             most common causes of
Perimetry map. The darker areas      aimed at reducing the production        “visual impairment”.                   
represent the scotomas.
               Laser treatment
                                                        When medication is not enough


     Laser treatment                        How is the treatment                       the specialist to focus the laser

     When the use of eye-drops
                                            performed?                                 beam. The procedure is usually

                                            A fter an eye-drop of local
                                                                                       painless even though at times there
     and/or tablets is not sufficiently                                                is some discomfort (needle prick
     effective or poorly tolerated, one     anaesthetic is applied to the              sensation) and the patient can be
     can consider laser treatments,         eye, the treatment is performed            bothered by the flashes of light.
     which vary depending on the            by placing on the patient’s eye a          The treatment takes only a few
     type of glaucoma. In the case of       special contact lens that enables          minutes.
     “closed-angle glaucoma” the
     treatment used is yag Laser
     Iridotomy. The procedure used
                                            Laser iridotomy
     for “chronic open-angle glaucoma”
     is Laser Trabeculoplasty. Laser                                                      Trabeculum
     treatment may also be used as a
     first choice approach instead of the
     pharmacological treatment.




                                            fig. 1


                                            The laser is “aimed” at the edge of the
                                            iris (Fig. 1) where a tiny hole is made,
                                            this hole allows the aqueous humour
                                            to pass towards the filter known as
                                            trabeculum (Fig.2).
     What iS a laSer?
                                            The Yag        laser iridotomy
        A laser is a beam                   consists in making a tiny hole in
     of homogeneous and                     the iris thus allowing the chambers           Iridotomy                 fig. 2
     powerful light.                        of the eye in front and behind the
     Different types of
     laser lights are used in               iris to connect. This procedure            prophylaxis in patients at risk of
     ophthalmology in order                 favours the forward circulation of         the onset of an acute attack. It is
     to take advantage of the               the ocular fluids towards the filter       also used as preventive treatment
     peculiarities of each beam.            and can prevent the sudden closure         for the “other” eye of someone who
     The effect of the laser
     radiation on the target                of the drainage angle.                     has had an acute glaucoma attack in
     can be tissue evaporation,             The iridotomy is used as treatment         one eye. It may be useful to avoid
     incision or heating.                   for closed-angle glaucoma and for          or postpone the surgical treatment.
10
What iS a YaG               The Yag laser is used, in this case, for its
laSer?                    capacity to create microincisions, aimed at
                          making a tiny hole in the iris.




Trabeculoplasty                                                            Results

                                                                           In most cases a decrease in
L aser
                                                                           ocular pressure is obtained.
              trabeculoplasty                                              Since the amount of this
improves the functioning of the                                            decrease depends upon many
drainage filter of the aqueous                                             factors, it is impossible to
humour by widening its pores                                               predict either the final effect or
and thus reducing the ocular                                               whether it will be sufficient to
pressure (Fig. 1 and 2).                                                   prevent further damage by the
The actual target of the treatment                                         glaucoma, and for how long.
is the filter of the drainage angle,                                       For successfully treated cases
located between the iris and                                               this technique enables the
the cornea, which fails to work                                            postponement of surgical
correctly in patients with open-                                           treatment for a long time and
angle glaucoma.                                                            it may enable the reduction of
Since this filter is known as                                              pharmacological treatments,
“trabeculum”, this laser technique                                         even though in most patients
is named “trabeculoplasty”.             fig. 1                             the use of anti-glaucoma eye-
                                                                           drops is still needed.
                                                                           Laser treatment is applied as
                                                                           an “additional option” for
                                                                           controlling a chronic disease
                                                                           lasting one’s entire life. For this
                                                                           reason, even when a remarkable
                                                                           reduction in pressure with the
                                                                           laser treatment is obtained,
                                                                           it is important to continue
                                                                           to undergo examinations as
                                                                           planned.




                                                                           Laser trabeculoplasty is
                                                                           performed using a mirror lens
                                                                           (Fig. 1) that points the laser beam
                                                                           on the trabeculum (Fig. 2). The
                                                                           use of the laser (arrows) produces
fig. 2                                                                     better functioning of the filter.
                                                                                                                 11
              Glaucoma
              surgery                                                                 Before it is too late


    Why and when                              called the conjunctiva, lining the       known as trabeculectomy or
    glaucoma surgery                          eyeball. An operation of this type is    “filtering operation”.

    Whenever           incisional surgical      Trabeculectomy involves the removal of
                                                a small block of tissue to obtain a “valve”
                                                                                              Filtration bleb
    intervention becomes necessary to           through which the aqueous humour
    keep the glaucoma under control, the        filters and, by accumulating
                                                under the conjunctiva, forms
    eye specialist/ophthalmologist has          the filtration “vescicle”
    to chisel a new drainage channel            or “bleb”.
    to allow the aqueous humour to
    escape from the internal part of the
    eye. The surgical intervention is            Fragment
    recommended to avoid damage to               removed
    the optic nerve, damage that would                                                           Valve
    otherwise inevitably progress. Surgical
    treatment is, therefore, indicated
    when either the laser treatment
    or medication is not effective in
    lowering the intraocular pressure.
    The complications from modern
    anti-glaucoma surgery are fortunately
    rare. It is important to remember that
    there is no “ideal” pressure value in
    an absolute sense and all the efforts
    made are always aimed at preventing
    worsening of the damage. Surgical
    treatment may have specific uses
    in different patients with the same
    intraocular pressure but with different
    degrees of severity of their disease.

    How does glaucoma surgery
    work?

    The objective of the surgical
   treatment is to create an efficient
   drainage channel that is an
   alternative to the “diseased” ones,
   thus linking the space between
   the iris and the cornea and the one
12 situated under the membrane,
                                       microSurGerY

                                          Surgical interventions
                                       on the eye are usually
                                       performed with
                                       microsurgical techniques,
                                       i.e. using the surgical
                                       microscope, which
                                       magnifies the details of
                                       the eye being operated
                                       on and achieves extreme
                                       precision.



                                                                            aqueous humour through the
Filtering surgery                                                           wall of the eyeball by spreading
                                                                            it backwards, under the

This operation is performed
                                                                            conjunctiva, thus lowering the
                                       Complications                        ocular pressure. In other patients

                                       During glaucoma surgery
under local anaesthetic and can                                             where a drainage operation is
be carried out at day hospital. It                                          not practicable, it is possible to
consists in the removal of a tiny      the most relevant complication       attempt to reduce the formation
block of tissue from the eye wall.     is haemorrhage. On the               of the aqueous humour by
This creates a channel that allows     other hand, during the post-         selectively damaging parts of the
the fluid to drain from the drainage   operative period the following       “ciliary body”, i.e. the structure
angle, not directly to the outside     problems may occur:                  behind the iris that produces it.
but to a space within the ocular         very low ocular pressure           Operations of this type may
wall. The effective functioning          internal haemorrhage               be carried out using a freezing
of the valve made by the surgeon         increased opacity of the           probe or a laser beam.
results in the formation of a            crystalline lens
swelling like a vescicle, called by      infection
doctors “filtering bleb”, where          increased ocular pressure          Prevention

                                                                            A lthough most treatments
the aqueous humour accumulates         These events are not very frequent
under the conjunctiva before           and can usually be resolved.
spreading backwards. Sometimes,        However, the eye specialist will     effectively lower the ocular
because of the natural scarring,       recommend the surgical treatment     pressure, there is no definitive cure
the valve may close and the ocular     only when all other treatments are   for glaucoma and it is not possible
pressure may again increase. It        not effective or well tolerated.     to restore the visual function
is for this reason that the use of                                          already damaged by the disease.
substances capable of reducing                                              The treatment can prevent further
the scarring activity, known as        Other surgical operations            worsening, especially if carried out

                                       I
“antimetabolites”, has been                                                 in the early phases of the disease.
introduced. These substances are          n certain cases an operation
applied during the operation or        may be necessary to insert a
                                                                                Especially in middle age,
during post-operative examinations     small plastic valve. The function
                                                                             even in the absence of any
to maintain effective filtration.      of these “draining implants”          symptoms, it is important
                                       is to allow the escape of the         to undergo specialised
The structure that
produces the aqueous                                                         examinations to recognise
humour is known as                                                           the presence of glaucoma
“ciliary body”
                                                                             or other ocular diseases
                                                                             in their initial stages,
                                                                             before they cause serious
                                                                             irreversible damage.
                                                                                                                    13
              Questions
              & Answers
     Can glaucoma be hereditary?                             Are tears made of aqueous humour?
     Not always. It is, however, more common among           No, the aqueous humour does not flow to the
     close blood relatives of affected persons.              surface of the eye.
     Is it present for life?                                 Can glaucoma treatments improve the
     Once the glaucomatous disease develops it will          eyesight?
     remain forever even if treated.                         No, the aim of the treatment is to prevent
     Is it possible to have it in only one eye?              further deterioration of the visual function.
     Certainly, although both eyes are commonly              Why is it that after an eye examination the
     affected with different degrees of severity.            eyes become yellowish?
     Is it contagious?                                       A yellow dye is used during the test with “blue
     No.                                                     light” to measure the pressure of the eye.
     Can it cause other ocular diseases?                     What does it mean to make a “curve” of
     Not normally, though there might be other               the ocular pressure?
     concurrent eye diseases.                                It means to measure the ocular pressure several
     Can it cause blindness?                                 times during the day or night to uncover its
     Yes, if the progression of the disease is not stopped   variations.
     with appropriate treatment.                             Is it necessary to see an eye specialist in
     Do spectacles help?                                     addition to the examinations already
     No, spectacles are useful only to see more sharply.     planned?
     Can one continue to wear contact lenses?                No, unless you notice symptoms such as pain,
     Certainly, but you must always follow the eye           hazy vision, coloured halos around electric lights
     specialist’s advice.                                    or something else.
     Can you practice sports and do yoga?                    When is it advisable to have a preventive
     Yes, as long as you avoid those sports in which         eye specialist examination?
     the position of the head is kept lower than the         It is important to see an eye specialist, even in
     chest for extended periods of time.                     the absence of symptoms, if you are more than
     Is it O.K. to drink alcohol and coffee?                 40 years old and have not had an eye specialist
     Within reasonable limits, even though it is not         examination within the previous 5 years.
     advisable to drink anything, including water, in        Otherwise, every 3 years between 40 and 60
     excessive amounts and over a short period of time.      years and every year thereafter.
     In case of pregnancy is it important to tell            What is the vescicle that is visible by
     the eye specialist?                                     lifting the eyelid after the glaucoma
     Yes, it is necessary to tell the eye specialist about   operation?
     the pregnancy and the gynaecologist about the           It is the conjunctiva raised by the aqueous
     treatment for Glaucoma being used.                      humour that filters through the small valve
     Is it O.K. to drive?                                    that the surgeon has made in the eye wall. It is
     Yes, as long as the visual function is within the       known as “ filtering bleb”, it may initially be
     limits set by law for driving.                          uncomfortable though, usually, only temporarily.
1
         Ten suggestions
         to follow
1 - Is it necessary to get up at night to             8 - Why are some patients treated with
carry out the treatment?                              both eye-drops and tablets?
Not usually. It is best to organise the times         In some cases it is necessary to take both types of
of treatment in such a way that you can rest          medication to strengthen the therapy.
uietly.                                               9 - Is it possible to use other medication in
2 - How long and where should you                     addition to glaucoma medication?
keep eye-drops from the time they are                 It is very important to tell the family doctor
opened?                                               about the diagnosis of glaucoma and the
Usually for a month, preferably in a cool dark        medications being used. For instance,
place. If the eye-drops change colour then they       you should be careful when taking some
must be discarded.                                    tranquillisers, anti-asthmatics or medication
3 - What happens if you forget to                     for the digestive system because they could have
administer the eye-drops?                             an effect on the ocular pressure.
If there is a long delay the ocular pressure          10 - How long does it take for the eye-
increases, it is therefore best to stick to set       drops to be absorbed?
times even though, occasionally, a variation          A few minutes, after that it is O.K. to have a
is allowed.                                           shower, a bath or go swimming.
4 - Should you apply eye-drops before the
eye specialist examination too?
Unless there are precise indications from the
doctor, the treatment should continue as
normal.
5 - If two types of eye-drops have to be
administered at the same time, can you
apply them together?
It is necessary to wait a few minutes between
the first and the second eye-drops.
6 - If you are not sure that you have
applied the first eye-drop correctly, is it
dangerous to apply a second one?
No, although it is best to dry the eye
immediately, to prevent the extra eye-drop from
flowing into the tear duct.
7 - Is it dangerous to use the eye-drops
more frequently than prescribed?
It is not dangerous, but it has no positive effects
on the progression of the disease, and it could
lead to undesired effects.
                                                                                                            1
European Glaucoma Society
       www.eugs.org

				
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