COMMON SYMPTOMS OF EYE DISEASE
Visible redness of the one or both eyes is a common symptom pertaining to several varieties of diseases. One should
not mistake every red eye as having viral conjunctivitis (So called Madras eye/Sore eyes). Hence do not self medicate
and delay seeking medical advice if you have a red eye. It could be something serious like acute attack of high
intraocular pressure, or inflainflammation in the eye (iridocyclitis).
Stickiness of eyelids:
A common symptom of infection in the eye is stickiness of the eyelids due to discharge. This infection could be purely
external or could be more serious. Persistent stickiness of the eye lashes needs early evaluation.
Double vision:
Normally the image formed by the two eyes is coordinated into a single image by the brain. Two distinct images are seen
once this coordination is disturbed due to various diseases involving the muscles of the eye and the nerves that control
the same. Multiple images often are an early symptom of cataract.
Loss of Vision and blurred vision:
Vision can be defective to a variable degree. It may be easy to detect gross decrease in vision but it may be more
difficult to detect subtle degree of loss of vision. It is very easy to miss gross loss of vision in one eye when the other eye
is healthy unless one consciously tests each eye separately. It is a good practice to test each eye separately at regular
intervals using any fine reading material such as newspaper.
Watering:
Watering could be the result of mal alignment of the eyelids or eyelashes or a blockade of tear ducts that normally drain
the tear fluid into the nose. Presence of tearing in newborn babies can indicate lack of patency of the tear ducts and
may need attention.
White reflex in the eye:
Normally the center of the eye gives a black reflex due to the pupil. A white reflex can be due to opacification of the
normally transparent cornea, the lens (cataract) or due to an abnormal growth of tissue behind the lens. A white reflex
in a child can potentially be dangerous and should not be ignored.
Drooping of the eyelid:
Drooping of the upper eyelid could be present at birth or could occur later. If the defect has occurred later in life one
should note the frequency of the occurrence and in what part of the day it is more prominent. These observations can
help the doctor make important decisions.
Squinting of the eyes:
Squinting indicates the misalignment of the eyes. In children, this can potentially lead to reduction of vision in the
squinting eye due to disuse (lazy eye). When in doubt, taking photographs with flash can help identify the squint in the
photographs. This is especially useful to the doctor, in case of children who refuse to cooperate with the doctor for
adequate examination.
Abnormal looking eye:
Abnormal look of the eye could be due to prominence of the eye, or could be the result of defects involving the eyelids.
Prominence of the eye could be due to large eyeballs or due to protrusion of normal sized eye by abnormal growth
behind the eye. Any change in appearance of the eye should be investigated. Previous photographs could be useful in
comparing especially when one is not certain about the time of onset of the abnormal look of the eye.
General examination terms:
Vision testing:
Vision testing involves making a person read standard sized letters at a specified distance. The doctors record the vision
as a fraction e.g. 6/6 etc. The top number denotes the distance (in feet) at which the patient has been able to read the
particular sized letter while the bottom number indicates the distance at which a normal person is expected to read the
same letter. Near vision is tested separately in good illumination using special test charts held at normal reading
distance. The testing is done with each eye separately. The doctors often test the vision using a pinhole. This gives an
estimate of improvement possible with glasses. The patient in place of glasses cannot use the pinhole.
Refraction:
This is an important test that is done by the ophthalmologist or more often by the optometrist. The eye is like a camera.
The light rays are focused on to the light sensitive film in the back of the eye called the retina. This focusing is made
possible by the cornea (a clear watch glass like structure in the front of the eye) and by the lens in the eye (similar to the
lens of a camera). Refraction is done usually in the normal state. On occasion (especially in children) it may have to be
done using special eye drops (cycloplegics). In this situation one may have to retest the power of the required glasses 23 days after the testing with the use of drops. Refraction involves two parts. The first part is objective where in the
refractionist estimates the power needed by using a test called retinoscopy. This test can also be done with a machine
called the automatic refractometer (so called computer testing). However one still needs to do the all-important
subjective testing (i.e. testing the response of the patient with different powered glasses) before prescribing the glasses.
Hence do not be misled by the so-called computer testing.
Amsler grid testing:
This test is done in selected group of patients depending upon their symptoms. The test involves looking at a chart that
has a grid drawn with a central dot. The test is done using the near vision glasses (if one is using the same). The test
permits the evaluation of function of the central 20 degrees of the retina.
The patient is asked to look at the central dot and tell whether All the corners of the chart are seen All the lines are seen
straight and not crooked There are any areas of gray patches where the lines are not seen. Whether the central part of
the chart or the peripheral part of the chart is clear. The Amsler's chart is very useful as a home monitoring device. If any
defect is noted, immediate ophthalmologic examination is warranted.
Dilatation:
One of the most common procedures that is done in an eye specialist's office is dilatation. The pupils of the eye constrict
or dilate depending upon the light that thrown at the eye. For examining the back part of the eye (fundus), the doctor
uses an instrument called ophthalmoscope. To get a good view of the back of the eye, one needs to dilate the pupils.
This permits more light to enter the eye and gives a better image of the fundus. To keep the pupils dilated despite the
intense light, one needs to dilate the pupils. There are various types of dilating drops available. The faster acting ones
may dilate the pupil in 15-20 minutes time. Other variety of drops may take up to 30-45 minutes for good dilatation. The
effect of dilatation usually lasts up to 6 hours. Some of them may retain the effect for 24 hours. Usually the drops used
for routine eye examination do not have long lasting effect. A patient is expected to have glare in the sun light while still
under the effect of the drops. Hence driving may become difficult. If you had similar dilatation in the past and have been
noted to be allergic to any one of them, please inform the same to your doctor.
Slit lamp examination:
Slit lamp is an instrument that has an in built microscope and a bright illumination system. The special arrangement of
the light and the microscope allows the doctor to view the eye in great detail under high magnification.
The front part of the eye is examined without any other aids while the back part of the eye (fundus) is examined with
help of special lenses held in front of the eyeball.
Tonometry (eye pressure check):
Tonometry involves the check of the pressure of the eye. Normal pressure is a range and not a finite number.
Raised pressure in the eye can be harmful to the nerve connecting the eye with the brain (optic nerve). The pressure is
normally checked in one of the three ways.
Schiotz tonometry:
Here a metallic device is placed on the eyeball and the deflections of the needle on the scale are used as a guide to
measure the eye pressure. At the best, this modality of testing can be used only as screening device. This is not very
accurate.
Applanation tonometry:
In this a small prism mounted on the slit lamp is used to contact the eyeball and measure the pressure. This modality of
testing is more accurate and is the standard today.
Non Contact Pulsair Tonometer:
This is an electronic device that is very accurate and useful in specialized situations. It is also useful in screening
outpatients routinely. The test is totally painless.
Gonioscopy:
Gonioscopy is the test in which the angle of the eye is examined. A fine balance between the inflows of fluid and it's
outflow maintains the eye pressure . The outflow is through the angle of the eye. Studying this angle gives a lot of
insight into the cause of a condition called glaucoma. This test is done with the help of the slit lamp and a special lens
called gonioscope. The eye is anesthetized by placing a few drops of anesthetic to facilitate placement of the lens. This
test is totally painless.
Ophthalmoscopy:
This is a very important step in the total examination of the eyes. The visible portion of the eye is easily examined by the
slit lamp examination. The back portion of the eye can only be examined by using the ophthalmoscope. This step usually
needs dilatation of the pupils. This test involves throwing bright light into the eye and examining the image of the back
of the eye using special lenses. For Indirect opththalmoscopy, the patient has to be in the reclining position for proper
examination. Sometimes the slit lamp may be used for detailed evaluation of the areas of the back of the eye such as
macula, optic disc etc.
Tests for patients undergoing cataract surgery :
Potential acuity meter testing (PAM):
Potential acuity meter testing enables one to have an idea about the possible visual recovery following cataract surgery.
In this testing the doctor projects a chart of letters or numbers into the back of the eye through the gaps in the cataract
that enables the patient to read the letters. Depending upon the number of lines that one could read, the potential for
recovery of vision is estimated. One should realize that this is only an approximate estimate and very often the true
recovery of vision is greater that the estimate.
Glare testing:
The glare testing permits one to assess the deterioration in vision that occurs with glare. Cataract can produce
significant scattering of light. Hence people with early cataract may have good vision under ideal conditions of testing
but the vision may deteriorate rapidly under conditions of glare. This testing enables one to decide on the need or
otherwise for cataract surgery.
DBR: This is a very important test that enables one to calculate the desired power of intraocular lens during the cataract
surgery. This artificial lens implanted in the same location as the natural lens permits one to have good vision without
needing to use the thick glasses or contact lenses after cataract surgery. The test involves use of ultrasound to measure
the length of the eyeball and this information along with keratometry (the measurement of the curvature of the cornea)
is used to calculate the IOL power by a complicated formula.
Special tests for corneal diseases
Schirmer's test:
Schirmer's test is a measure of the tear secreting capacity of the eye. Deficiency in tear secretion can lead to a chronic
condition called dry eye. The test involves placement of a special filter paper strip across the lower eyelid margin and
measuring the length of the strip that is wetted by the tears over a one-minute period.
Keratometry:
Keratometry involves the measurement of the corneal curvature in two meridians. The cornea is the front portion of the
eye that is clear like a watch glass. The curvature of the cornea helps it to focus the light partly. Measurement of the
corneal curvature is needed for fitting proper contact lens. It is also needed for the calculation of the IOL power before
cataract surgery.
Corneal topography:
Corneal topography is the detailed mapping of the surface of the cornea. Advanced computer analysis of several spots
on the surface of the cornea using the study of the reflected image is done. Color coded graphs of the surface map
enable the doctor to diagnose certain conditions such as keratoconus. Before undergoing excimer laser treatment for
getting rid of glasses, one needs to perform this test to understand the surface of the cornea better and plan the
treatment accordingly.
Pachymetry:
Pachymetry is the study of the thickness of the cornea. The accurate measurement of the thickness is made possible by
using ultrasound or optical means. Measurement of the thickness is important in the diagnosis and management of
certain corneal conditions such as keratoconus, corneal endothelial dystrophy etc.
Specular microscopy:
Specular microscopy is a test that enables the evaluation of the back most layer of the cornea called the endothelium.
The health of this layer is important in maintaining the clarity of the cornea. With age, injury, surgery and in some
diseases this layer may have reduced number of cells and become abnormal. Study of this layer is done by counting the
number of cells per square millimeter as well as study the type of the cells. This study is important in planning certain
surgeries.
Special tests for glaucoma
Field charting:
Field of vision describes the side vision when one is looking straight ahead. The testing of the extent of the side vision is
important in the diagnosis and follow-up of several disease including glaucoma, and diseases relating the eye with the
brain (neuroopththalmology). The test is usually done on computerized machines (Humphrey field analyzer). The
machine is programmed to test several points, sometimes repeatedly with varying illumination. The test may take time
depending upon the defect in a given patient. The computer has inbuilt software that enables comparison of the field
charting on repeat testing of the same patient.
Optic disc photography:
Optic disc is the only part of the optic nerve visible to the eye doctor in the back of the eye. The appearance of the disc
gives valuable information to diagnose and treat conditions such as glaucoma. It is important to be able to compare the
appearance of the disc over a period time in cases of chronic glaucoma. This is made possible by several techniques- one
of which is the photography of the disc using the fundus camera.
GDx nerve fibre analyzer:
This recent innovation allows measurement of the thickness of the nerve fiber layer, which is the part of the retina that
is first affected in the disease of glaucoma. The nerve fibril layer defect is detected long before any defect is noted in the
function of the eye including the field examination. This test may help in the early detection of significant damage
caused by glaucoma and help in the follow up of these patients. The test involves the use of scanning laser that passes
through the nerve fiber layer and in the process undergoes a process called retardation. By measuring the extent of
retardation the machine calculates the thickness of the nerve fiber layer.
Ultrasound biomicroscopy (UBM):
This is an advanced technology in ultrasonography, which permits high-resolution pictures of the front of the eye. The
technology enables the measurement of the angle of the eye, which is otherwise not accessible for measurement. The
angle of the eye is the path through which the fluid in the eye finds access outside. The angle can become closed in
certain individuals. This propensity to closure of the angle can be more adequately predicted using this advanced
testing. Following injury to the eye, sometimes abnormal communications develop leading to excess drainage of fluid
and resulting soft eyes. These abnormal sites can be best identified by UBM.
Special tests for neurophthalmology
Hess and diplopia charting:
These two tests enable the measurement of misalignment between the two eyes. This type of problem leads to a
condition of double vision in a patient. The extent of the double vision and the direction in which it is maximal can be
charted by using these two tests. The tests are done using red and green goggles where in one colored glass is placed in
front of one eye and the other in front of the other.
Contrast sensitivity testing:
Certain disease of the retina and optic nerve leave behind subtle defects of sensitivity. A patient is very symptomatic of
these deficiencies but the commonly performed tests like the vision testing do not reveal the true extent of the defect.
Measurement of contrast sensitivity enables one to understand these subtle defects in the visual function. This test
involves identification of patterns of gray on gray background.
Color vision testing: Color vision is an important component of human vision. Defects in this can be by birth or due to
any acquired diseases. The testing is done using one of the two methods. Ishihara's charts- In this, many charts are
presented and the patient is asked to identify the letters or numbers in the chart. Farnsworth- Munsell 100 hue test- In
this the patient is asked to arrange several caps of different hues in their order. The test is done in good illumination.
Visually evoked potential (VEP):
In this test bright light or patterns of dark and light bands are projected on to the eye. The electrical potentials that are
generated in the brain as a result of the light or pattern are recorded. This gives valuable information regarding the
functional intactness of the optic nerves and the optic pathways that normally conduct these impulses to the brain.
CT scanning:
CT scanning is a computerized system where in x- rays are used to construct images of thin slices of tissues allowing
detailed evaluation of the tissues under consideration. By manipulating the soft ware, the image quality and detail can
be enhanced. Injecting some drugs called contrast agents can get additional information. CT scanning is very useful in
the evaluation of diseases of the orbit (bony cage in which the eye is located) as well as some diseases of the eye itself.
Injury related problems - especially presence of foreign bodies is easily picked up and located on CT scanning.
MRI scanning:
MRI scanning is a different technology and looks at the tissues in a different perspective. Sometimes both CT and MRI
scanning may be needed to understand some diseases. MRI is especially useful in diseases of brain that may affect the
eye. By using some specialized soft ware, one can even image the blood vessels of the brain without injecting any drug
(MR Angiography 12th May ’12).
Fundus photography:
Fundus photography permits documentation of the structures of the eye. This documentation may be important to
compare with other investigations such as fluorescein angiography as well as for follow up.
Fundus photography of the optic disc is important in the management of glaucoma.
Fundus fluorescein angiography (FFA):
This is an important test to evaluate a variety of retinal disease such as diabetic retinopathy. This is one of the
commonest tests performed for retinal diseases. The test involves injecting a dye called sodium fluorescein into the
blood stream and taking photographs of the retina using special filters. The test is important to stage the disease as well
as to guide treatment with laser photocoagulation. Present generation digital cameras permit manipulation of the
pictures and for instant viewing without need for development of the film etc.
Indocyanine angiography (ICG):
Indocyanine angiography is similar to the fluorescein angiography but involves injection of a different dye called
Indocyanine green. The test utilizes a special infrared sensitive camera to capture the images digitally. Very often
indocyanine and fluorescein angiography are combined in a given patient to give maximum information. Indocyanine
angiography gives more information regarding the choroidal vessels compared to fluorescein angiography that gives
more information regarding the retinal blood vessels.
Electroretinography and Electrooculography:
These two tests are done to evaluate the function of the retina. Light is projected onto the retina and electrical
potentials that occur normally in the eye are recorded using special electrodes placed near and on the eye. Certain
retinal degenerative diseases are diagnosed only on testing with electroretinography. Specialized computer soft ware is
needed to analyze the data.
Low vision aid testing:
There are certain diseases that may lead to permanent partial loss of vision. These patients can be sometimes helped to
some extent by using special aids called low vision aids. There are a variety of these available and most of them are fine
tuned for a specific function. Most of them have been made to enable reading fine print. It is important that the patient
should be motivated to use them. They are used at a closer range than normal working distance and hence one needs to
get used to the same. Computers and closed circuit television are also useful as low vision aids. One has to test different
varieties before choosing what is appropriate for them.
Ultrasonography:
Ultrasonography is test that permits the evaluation of the back of the eye in case of opaque media. In a normal eye one
is able to see the back of the eye using instruments such as indirect ophthalmoscope. In conditions of disease and injury
the cornea, the lens or the vitreous cavity can become opaque and prevent this visualization. In these circumstances,
ultrasound can be used to scan the eye and get useful information about the tissues lying behind the opaque media. This
information is needed not only for proper diagnosis but also to plan the surgery where indicated.
Special tests for squint and related disorders
Cover test and prism tests:
An important part of the evaluation of a patient with squint is the cover test and prism tests. These tests are conducted
in the office of the eye doctor itself. Using these tests the eye doctor is able to classify the type of the squint and to
grade the severity of the same. This information is needed to plan the treatment including surgery where needed. With
a torch light and a set of loose prisms the eye doctor is able to evaluate squint to a great degree.
Orthoptic evaluation:
Orthoptics is the study of how effectively the two eyes function together (binocular vision). This testing is done on many
instruments including the synaptophore. Special instruments are used to measure the near point of convergence and
near point of accommodation. These points give a guide as to how difficult it is for a person to view near objects. Many
people with eyestrain on performing near work may be helped by exercises after the orthoptic evaluation.
SYRINGING
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Some patient with watering problem or chronic discharge may have to undergo syringing.
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There is a tube connecting the eye and nose which is called nasolacrimal passages( duct)
To check whether there is any block in the lacrimal passages syringing has to be done.
Procedures
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Syringing is the process by which saline is passed through the lacrimal punctum – an opening in the medical
side of the eyelid.
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If there is any block saline will come back through the same punctum or the upper punctum.If block is not
there the medicine will reach the throat.
Patient preparation before syringing
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Patient has to lie down for the procedure.
Local anesthetic drops has to be instilled and then saline will be pushed through the lacrimal punctum.
Treatment
If the patient has block surgical treatment may be needed. If there is any infection syringing several times with antibiotic
solution may be of help.
FUNDUS FLUORESCEIN ANGIOGRAPHY (FFA)
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Fundus Fluorescein angiography (FFA) involves injecting a dye called sodium fluorescein through the
veins in your arm which eventually reach the blood vessels in the retina and rapid photographs are taken.
This helps in diagnosis and management of the retinal condition and it also helps to decide about the
laser treatment.
Patient should preferably be on an empty stomach 2-3 hours prior to the procedure.
This test is not advised for pregnant ladies and patients with kidney problems.
Some patients may have a sensation of vomiting soon after the injection. This usually passes of within
about 30 seconds.
Breathing in deeply through the mouth helps to overcome this.
Very rarely, allergic reactions and even death can occur. Urine and skin is coloured yellow for 24-48 hours
following the procedure.
INDICATIONS FOR FFA
1. Central Serous Retinopathy: - to find the site of leak so that laser can be applied to seal it.
2. Maculopathy & Diabetic Retinopathy
 To find out the site of leak before laser.
 To assess the blood supply to the macula which determines the efficiency of laser.
 To look for new abnormal blood vessels in which case a Panretinal Photocoagulation will have to be done
i.e. more extensive laser given.
3. Vascular occlusion (Retinal Vein Occlusions)
To assess the blood supply to the retina and to look for non perfusion areas, as well as to detect areas of
neovascularisation.
4 ARMD
To look for CNVM (Choroidal neovascular membrane) from which leak or bleeding has occurred.
LASER PHOTOCOAGULATION
Counseling of patients before laser
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Laser is done as an OP procedure. Admission is not required. Pupils have to be dilated before
laser procedure.
The patient is required to sit before the slit lamp and local anesthetic drops should be instilled
A special contact lens is put on the eye and the laser is focused. The patient should not move his
eyes and look in the direction advised by the doctor.
After focal laser there is no restriction. The patient can return home and resume normal
activities.
But patients with proliferative diabetic retinopathy should not lift heavy weights to prevent
bleeding.
In patients in whom bleeding has already occurred, rest in propped up position to facilitate
absorption of vitreous haemorrhage is advised.
Maculopathy
 Laser is to be applied to the site of leak. This is to prevent further leak from the site
 Laser will not improve vision. It is done to help prevent further deterioration of vision
PROLIFERATIVE DIABETIC RETINOPATHY
Laser will be applied all around the retina in two sittings to cause regression of the new vessels. (In some
cases one sitting is done to prevent the growth of new vessels where there are large non-perfusion areas).
 This is to prevent progression of the retinopathy. New vessels are fragile and tend to bleed easily.
 Further new vessels can occur at the angles and cause raised IOP, pain and redness.
 In end stage retinal detachment and total loss of vision can occur.
 Laser is done to prevent these complications from occurring and not be improving existing vision. If
done in time, laser will help to preserve vision.
 Full visual recovery occurs after laser. There may be visual blurring after the procedure due to macular
oedema. The effect of laser therapy starts showing 5 weeks after the procedure. Some patients may
require multiple laser sessions before retinopathy gets controlled.
 Although laser destroys the retina enough
LATTICE DEGENERATION/RETINAL TEARS
Laser is done to barrage the tear so that fluid does not seep through it and cause retinal detachment. In
degeneration laser is applied to barrage the areas of thinning or holes to prevent this complication.
CSR
The leak is closed by the laser to prevent further fluid from leaking. The existing fluid will get absorbed by
6-8 weeks, only then will visual symptoms subside.
OPTICAL COHERENCE TOMOGRAPHY (OCT)
Optical Coherence Tomography provides a non-invasive, non-contact high resolution cross-sectional image of
the retina comparable to a histopathological section.
Thus evaluation and follow-up of retinal pathologies is easier.
Indications of OCT:
OCT in diseases of Retina
1) Diabetic macular oedema
Helps to quantify oedema as well as classify it so that treatment decision making is easier. Follow-up of
response to treatment is also possible.
2) Macular holes and cysts
OCT helps to differentiate cysts from holes. Staging of macular holes is possible thereby helping to predict
the prognosis of surgery. The closure following surgery can also be assessed by this technique.
3) Age-related macular degeneration
To identify choroidal neovascular membranes, pigment epithelial detachments, scars etc on which
treatment will depend. Effect of treatment can also be assessed by OCT.
4) Identifying Vitreomacular traction and epiretinal membranes.
5) CSR:OCT helps to detect serous retinal detachment or pigment epithelial detachment and to measure
amount of fluid for follow-up.
6) Identify and quantity macular oedema and atrophy.
7) Measure retinal thickness change in response to therapy.
OCT in glaucoma
1.
Helps to detect nerve damage in patients with glaucoma at a very early stage. Nerve damage can be
detected at a much earlier stage than computerized visual field charting. Minimal progression can also
be detected at an early stage.
2.
Helps to measure the optic nerve head parameters including cup disc ratio, vertical and horizontal.
3.
Retinal nerve fiber layer thickness is measured and compared with that of normal population. Thus
any damage to any quadrants of the neuroretinal rim can be identified. In follow up, progression of
damage due to glaucoma can be assessed.
4.
Changes in the retinal nerve fibre layer precede field changes thereby facilitating early diagnosis and
better follow up.
5.
Pupils have to be dilated for OCT. It has to be repeated during follow up yearly and sometimes more
frequently.
YAG CAPSULOTOMY
 After the cataract surgery in some patients a membrane may form behind the intraocular lens. In some
patients it forms early, in some late.
 Due to this new membrane, the patient may suffer from blurred vision.
 This can be identified by examination under a slit lamp after dilatation
 By applying laser rays an opening can be made in the center of the membrane to help improve vision.
 This is a simple non invasive OP procedure and patient can return home immediately. There will be no
pain. The chances of complications are minimal and includes retinal detachment. We use very low energy
to prevent occurrence of retinal detachment in predisposed patients and haven’t experienced any such
complication so far. The patients who are predisposed to develop this complication are high myopes,
aphakic eyes, patients who have vitreous loss during cataract surgery.
Procedure
 Before the yag capsulotomy pupil must be dilated by instilling dilating eye drops 3 times
 It may take 1-2 hrs for pupil to dilate.
 When the pupil is dilated patient is seated in front of the slit lamp and local anesthetic eye drops are
instilled.
 Laser rays are focused by using YAG capsulotomy lens to punch a hole in the membrane.
INSTRUCTIONS AFTER YAG CAPSULOTOMY:
 Vision will be blurred for some time due to an oily layer in front of the eye. It should be washed off by
repeated cleaning of the eyes with water when you reach home.
 After Yag Capsulotomy patient has to instill steroid eye drops four times and antiglaucoma medication
twice (Dorzox or Brimodin) for one week).
 Vision may remain blurred for 2-3 hours after the procedure.
 After YAG capsulotomy patient may see floaters. It is normal. But if they see flashes they should consult the
doctor immediately.
 Patient should review after 1 week for examination
YAG Peripheral Iridectomy (YAG PI)
Why YAG PI is to being done? (Indications for YAG PI)
 Angle is the space between the cornea and iris. It is through this that the aqueous humor fluid in the eye
drains. If the patient has narrow angle they should undergo Yag PI to prevent sudden increase in
intraocular pressure when the patients pupil is dilated and the drainage angle gets blocked.
 Narrow angle can be identified by gonioscopy. Patients with narrow angle may develop angle closure
glaucoma. When the pupil dilates there may be closure of the angle leading to blockage of aqueous humor
drainage and raised intraocular pressure. Anxiety, less light situation like cinema hall, dark room, rainy
season, evening or by using dilating drops by ocular examination can predispose to this.
Prevention of angle closure
To prevent the block or to reduce the intraocular pressure a small opening is made in the periphery of iris, so
that the aqueous fluid can drain from the anterior chamber by passing the block.
Patient preparation before YAG PI
 Before YAG PI pupil must be constricted by putting pilocarpine eye drops 2% several times.
 Some patients may have dimness or darkness of vision after putting pilocarpine eye drops or may have
‘brow ache’. This has to be explained to the patient.
 It may take 1-2 hours for pupil to constrict.
 When the pupil gets constricted patient will be seated in front of the slit lamp and local anesthetic eye
drops are to be instilled.
 By using YAG iridectomy lens an opening is made in the iris with laser application. Some patients may
require multiple sittings depending on the thickness of the iris.
Potential complications
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Multiple sitting is needed if one sitting is unsuccessful in patient with thick iris.
Bleeding may occur very rarely and it usually gets absorbed spontaneously.
Intraocular pressure may increase transiently.
Uveitis (mild) can occur.
Corneal burns may occur.
Instructions after YAG PI
 After YAG PI patient has to instill steroid drops (prednisolone acetate) 4times daily and antiglaucoma eye
drops (eg: dorzolamide, brimodine) twice daily for 7 days.
 Vision may be blurred due to the jelly used during laser for few hours. Patient should again wash eyes
properly after returning home.
 Patient has to come for review after one week. If there is any problem patient should contact our centre
immediately.
OCULAR ALLERGY
 Some patients may be allergic to some medications. In such cases eyes may become red and swollen and
there may be itching.
 Patient should remember to inform the doctor regarding allergy to any medications. Explain to the patient
that CECC staff will put a sticker on their shoulder indicating the drops to be used. This sticker will be
removed after the test is over. Also a card showing that they are allergic to the drop will be issued which is
to be brought at all visits.
 In case allergy occurs, anti allergy drops will have to be instilled for a few days and the medications must
be changed.
Ocular Allergy in Children:
This is a chronic condition occurring in children. It usually occurs around the teens. It is seasonal (April – June) and
related to pollen allergy.
Symptoms:



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Redness.
Itching
Ropy discharge
Frequent blinking of the eyes.
Treatment:
 Long-term treatment with eye drops may be required. The disease tends to decrease in severity with time
and gradually subsidies over months to years.
 Do not start medicines or discontinue prescribed medicines on your own.
 It is dangerous to purchase “drops for allergy” (steroids drops) over the counter with out prescription from
the pharmacy as prolonged use of these drops for allergy can cause glaucoma and cataract in a group of
patients who are steroid responders.
DRY EYE
 Dry eye is a disorder of the tear film due to tear deficiency or excessive tear evaporation, which causes
damage to the ocular surface and is associated with ocular discomfort.
 This condition causes prolonged itching, burning, gritty sensation, dryness and foreign body sensation. It is
a chronic disease, which needs life long treatment.
 If left untreated dry eye disease can damage the delicate tissues of the surface of the eye and disrupt the
cornea, which may lead to impaired vision.
Precipitating factors
It may be the result of hormonal changes associated
 Ageing,
 Menopause
 Autoimmune diseases such as arthritis or medical conditions such as diabetes.
 Systemic medications which can induce dry eye include antihistamines, anticholinergics, diuretics,
hormones, antidepressants, beta blockers, chemotherapeutic agents etc.
 Environmental, occupational and life style factors such as smoke, dry air, dust, wearing of contact lenses
for extended periods of time and prolonged computer use can all exacerbate dry eye disease.
 Dry eye symptoms often improve with treatment, but the disease is not usually curable. Because most dry
eye conditions are chronic, repeat observation and reporting of symptoms over time are essential.
 For patients with mild dry eye, use of tear substitutes is indicated. As the severity of dry eye increases
preservative free tear substitutes, gels and ointments are used instead of conventional preserved tear
substitutes.
 Surgical treatment is reserved for patients with symptomatic moderate or severe disease. This includes
Punctal occlusion with plugs, thermal or laser cautery, which helps to preserve the natural tears.
Floaters and Flashes
What are Floaters?
 Floaters are clouds moving in your field of vision.
 Most often seen when looking at a plain background like a wall or sky.
 While floaters look as if they are moving outside the eye, they are actually tiny clumps of gel or cells in the
vitreous.
Causes of Floaters
 Posterior vitreous detachment. As you age, vitreous gel thins or shrinks forming clumps inside the eye and
pulling away from the back wall of the eye.
 Posterior vitreous detachment is more common for people who are near sighted
 Have had cataract of yag surgery
 Have had inflammation outside the eye
 Have had eye injury
What are Flashes?
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Flashes occur when the vitreous (gel like substance within the eye) pulls on the retina.
The flashes of light can appear off and on for several weeks or months.
Some flashes of light appear as jagged lines or “ heat waves” in both eyes can last 10 to 20 min.
These are usually caused by a spasm of blood vessels in brain.
Causes of Flashes.
 Trauma to the eye, common experience when you are hit in the eye and see stars. Common ocular injury
results from baseball, golf, paintball, tennis, hockey etc. Always wear protective eyewear during sports nad
dangerous activity.
 As you age it is more common to age experience flashes.
Refractive errors

Inability to see clearly is often caused by refractive error.

Four types of refractive error
 Myopia (nearsightedness)
 Hyperopia (farsightedness)
 Astigmatism
 Presbyopia
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In myopia the distance between the cornea and the retina may be too long

Light rays focus in front of the retina instead of on it.

Close objects will look clear, but distant objects will appear blurred.
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In hyperopia the distance between the cornea and the retina may be too short.

Light rays are focused behind the retina instead of on it.

In adults distant objects will look clear but close objects will appear blurred

In astigmatism the cornea is curved unevenly shaped more like a football than a basketball.

Light passing through the uneven cornea is not properly focused on the retina

Distance and close vision may appear blurry.

Presbyopia is a normal condition in which your eyes gradually lose the ability to see things up close.

When we are young the lenses in our eyes are flexibile and are able to change focus easily between
near and far objects.
Correcting refractive errors
 Eyeglasses are the most common method of correcting refractive errors; they refocus light rays on the retina.
 Contact lenses: float on the tear film that covers the cornea- they refocus light rays on the retina.
MACULAR DEGENERATION
 The damage that occurs in the macular region is called macular degeneration.
 Macula is a small central area in the retina at the back of the eye that is the macula that allows you to see the
fine details clearly and perform activities.
 If the macula is not functioning properly you will have blurring, dark areas or distortion in the central vision.
 Macular degeneration will affect your near vision and far vision.
 Central vision will get affected due to macular degeneration but peripheral vision remains normal at the early
stage. For example you could see the outline of a clock but will not be able to tell what time it is.
 Macular degeneration alone will not cause total blindness. Even in more advanced cases, patient will have the
vision to take care of themselves.
CAUSES OF MACULAR DEGENERATION
 Ageing is an important cause for macular degeneration. The changes that occur due to ageing process can lead
to macular degeneration. This is known as age related macular degeneration (ARMD).
 Macular degeneration is the leading cause of vision loss among the age group above 65 yrs
 Age related macular degeneration is divided in to 2 types
1.
2.
Dry Age Related Macular Degeneration
Wet Age Related Macular Degeneration
Dry Age Related Macular Degeneration
 It is the most common type of ARMD. It is caused due to the ageing and thinning of the macular tissues with
deposits called drusen in the macula.
Wet Age Related Macular Degeneration
 About 10 % of the macular degeneration is in wet form. In this type, new blood vessels grow under the retina.
 These new blood vessels leak fluid or blood and it thus affects the central vision
SYMPTOMS
 It can cause different symptoms in different people
 It is sometimes difficult to notice in the early stages.
 In some cases only one eye loses vision while the other eye continues to remain same for many years.
Following are some common symptoms
 Words on the page looks blurred
 A dark or empty area appears in the center of field of vision
 Straight lines look distorted
DIAGNOSIS
 Many people do not realize that they have a macular degeneration until blurred vision becomes obvious
 But an ophthalmologist can detect it in the early stage itself
 A simple vision test in which you look at a chart that resembles graph paper and trace the lines on it(Amsler
grid test)
 Viewing the macula with an ophthalmoscope
 Fluorescein angiography to find the abnormal blood vessels (choroidal neovascular membrane) under the
retina
 Optical coherence tomography.
TREATMENT
 Nutritional supplements
Antioxidants vitamins and zinc may reduce the impact of AMD in some people. Risk for developing advanced
stages of AMD can be reduced by about 25% when treated with a high dose combination of vitamin C, vitamin
E, beta carotene and zinc.
Deposits under the retina called drusen are a common feature of macular degeneration. It is not possible to
cure AMD by vitamin supplements nor will they restore the vision that you have already lost.
LASER SURGEY AND PHOTO DYNAMIC THERAPY
 Photodynamic therapy for subfoveal CNVM wherein a dye (Visudyne) is injected into the arm vein. This dye
concentrates in the choroidal neo vascular membrane which is then destroyed by applying a special type of
laser.
 Certain types of wet macular degeneration can be treated by laser surgery.
 It is an OP procedure.
 By applying laser beams to stop or slow the leaking blood vessels that damages the macula. If the neovascular
membrane is in the centre of the fovea ordinary laser will destroy the fovea and cause further fall of vision.
 Now a days Anti-VEGF factor are also used as a treatment for this. It is done by giving an injection into the
vitreous humor.
 This is usually done for wet kind of AMD
AMSLER GRID EYE EXAMINATION
 This examination is done for age related macular degeneration.
 You can check your central vision weekly by using an Amsler grid
 You may find changes in your vision that you would not notice
How to use the grid?
 Wear your reading glasses and hold this grid at 12-15 inches away from your face.
 Should cover one eye.
 While looking directly at the center dot, trace the lines seen and note whether all lines of the grid are
straight or if any areas are distorted, blurred or dark.
 This eye examination can be given to the patient and they can practice this at home.
PREOPERATIVE COUSELING OF RETINAL SURGERY
RETINAL DETACHMENT
Retina is a nerve layer at the back of your eye that senses light and sends images to your brain. When the retina
is pulled away from its normal position it is called retinal detachment. The retina does not work when it is
detached.
 Surgery is done to reposition the retina which is detached.
 It involves applying a band external to the globe to indent the sclera, draining the fluid under the
retina and applying laser to seal the hole or tear.
 If the retina does not reattach or if there is a very large posterior tear or if there is tractional
detachment, a vitrectomy may have to be done. The procedure is usually done under local anesthesia.
This is followed by injection of gas or silicone oil. Prone positioning post operatively is required
 In young patients or apprehensive patients, general anesthesia may have to be given.
 Admission is required for these patients one day prior to surgery and one or two days post surgery.
 Prone position is necessary for a brief period of 3-4 days after silicon oil tamponade. It is required for a
longer duration of 3-4 weeks after gas tamponade. Advise the patient not to travel by air in an
aeroplane as the gas inside the eye can expand, increasing the intra ocular pressure and causing
severe pain.
COMPLICATIONS
 Chance of reattachment is 94-95%. There is chance of redetachment in 5% requiring surgery.
 Chance of endophthalmitis or infections within the eye is minimum. But there is a chance of buckle infection
and extrusion in which case, the buckle may have to be removed.
 Complications of silicone oil are inflammation, glaucoma, cataract, corneal opacity and hypotony.
REMOVAL OF SILICONE OIL
 Silicon oil will have to be removed 1-2yrs after the surgery.
 This can be done only if the retina is attached and stable.
 Earlier removal may be required if the oil emulsifies or there is severe reaction in the eye raised
intraocular pressure uncontrolled by medications.
MACULAR HOLE SURGERY:
 Surgery involves removal of vitreous and injection of gas into the vitreous cavity.
 The patient will require a postoperative prone position of 6 hours daily in the first week, 4 hours in the
second week and 2 hours in the third week.
 Success rate in macular hole surgery is 80%. However distortion may persist in some.
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20% patients have chance of complications.
Hole may remain open in 10%.
Hole may undergo enlargement in 5%.
Retina detachment may occur in 5% patients requiring re-surgery.
Progression of cataract may occur in 60% patients which will require a subsequent phaco IOL surgery.
POST OPERATIVE COUNSELING OF RETINAL SURGERY PATIENTS.
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Rest is required for one month.
Do not rub operated eye.
Do not lie on the operated side.
Do not take head bath.
Do not lift heavy weight.
Some patients may require prone position for a specific number of hours per day according to the doctor’s advice.
STRABISMUS (SQUINT)
 Strabismus is a condition in which the eyes are misaligned and point in different directions. One eye may
look straight ahead while the other eye turns inwards (convergent squint) or outwards (divergent squint)
or upwards or downwards (vertical squint).
 Squint can be constant or intermittent example when the child is reading, tired or when he is looking in the
distance only one eye may squint or both eyes may alternate.
 It is a common condition among children, though it can occur later in eye. Strabismus may run in families.
For normal vision the images from both eyes are combined by the brain into a single 3- dimensional image
thus giving us depth perception.
 When one eye squints, 2 different images reach the brain. In a young child, the brain trains to ignore the
image of the misaligned eye and sees only the images from the straight or better seeing eyes thus losing
depth perception. Adults will develop double vision.
Consequences of squint:
1.
2.
3.
Amblyopia or lazy eye:When a child has a constant squint, he does not use the squinting eye (the brain
ignores the image from that eye). This will result in that eye having poor vision due to lack of use
which is known as amblyopia.
Poor binocular vision and depth perception.
Abnormal head position.
Some children adopt an abnormal head position to keep both eyes aligned.
Treatment
1.
Refractive errors have to be treated with appropriate glass correction. Some squints can be reduced or
even be cured by proper glass correction.
2.
3.
Amblyopia is treated by patching the good eye thereby forcing the child to use the lazy eye and
thereby develop vision in that eye.
Surgery is done to realign the eye and thus help to regain binocular vision. In adults, surgery is purely
cosmetic if squint has been present for a long time.
COUNSELLING FOR SQUINT SURGERY
1.
2.
3.
4.
5.
6.
7.
Surgery is done on the extra ocular muscles. Surgery is done to bring the eyes to a straight
position and not to improve vision.
It will not improve vision but will help in regaining binocular vision in children.
However, only after the eye is brought to the straight position, can normal visual development
occur. This is possible up to the age of 8-10 yrs. After that visual development is not possible ie eye
becomes amblyopic or lazy.
Hence in some cases surgery may have to be done at the earliest e.g. unilateral squint, large angle
squint.
Surgery is first done on one eye and the correction is assessed. Sometimes, surgery may have to
be done on the other eye at a later date.
The amount of correction occurring can only be assessed postoperatively. It will depend on the
amount of healing and fibrosis taking place.
The eye will remain red for 2-3 weeks. Some patients may have diplopia. This is due to different
areas of the retina getting stimulated. This will disappear after some time.
DIABETIC RETINOPATHY
Diabetes is a condition when there is an increased level of blood sugar in the body.
If the patient is having diabetes for more than 10yrs and also if his diabetes is uncontrolled, there is a 60-70
percent chance of developing changes in the blood vessels.
This damage occurring to the retinal vessels due to diabetes is referred to as diabetic retinopathy.
Predisposing Factors:
1. Increased duration of diabetes.
2. Uncontrolled diabetes.
3. Associated factors such as hypertension, hypercholestremia, renal failure, anemia.
4. Pregnancy
Hence control of these factors can help prevention and delay progression of diabetic retinopathy.
Types of Diabetic Retinopathy:There are 2 main types of diabetic retinopathy
 Non-proliferative diabetic retinopathy (NPDR)
 Proliferative diabetic retinopathy (PDR)
Non - Proliferative diabetic retinopathy (NPDR)
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This is the early stages of diabetic retinopathy. In this stage tiny blood vessels within the retina leak
blood or fluid. This leaking fluid causes the retina to swell or to form deposits called exudates
Many people with diabetes have mild NPDR which usually does not affect vision. When macular
ischemia or macular oedema develops their vision may be affected.
Macula is a small area in the center of the retina that allows us to see fine details clearly.
The swelling or thickening of the macula is known as macular oedema. Cholesterol deposits called hard
exudates may occur at the macula.
Macular ischemia occurs when small blood vessels close. Vision blurs because the macula no longer
receives sufficient blood supply to work properly.
Proliferative diabetic retinopathy (PDR)

This is present when abnormal new blood vessels begin to grow in the surface of the retina or optic
nerve head in an attempt to revascularise the ischemic retina.
 The retina responds by growing new blood vessels, which do not re supply the retina with normal blood
flow.
 These new vessels are friable and tend to bleed easily leading to vitreous hemorrhage.
 These new blood vessels may form membrane and exert traction on the retina.
 PDR causes visual loss in the following ways.
 The new blood vessels may bleed into the vitreous, a gel like substance that fills the center of the eye
known as vitreous humor. Leaking blood might block out all vision. It may take days, months or even
years for the blood to resolve depending on the amount of blood present.
 These abnormal blood vessels may grow scar tissue that can pull the retina away from the back of the
eye. This is called a retinal detachment.
 If left untreated, retinal detachment can cause severe vision loss.
 Sometimes abnormal new vessels can grow in the anterior portion of the eye carrying raised
intraocular pressure, pain, redness and loss of vision.
Symptoms of diabetic retinopathy
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There are usually no symptoms of background retinopathy.
Sometimes gradual blurring of vision may occur if macular oedema is present. You may never notice
changes in your vision
A medical examination is the only way to find the changes inside the eye. When bleeding occurs your
sight may become hazy, spotty or even disappear altogether.
Proliferative retinopathy is a severe form of the disease and requires immediate medical attention.
Pregnancy and high blood pressure, renal failure, anemia may aggravate diabetic retinopathy
Eye Examination in diabetic retinopathy
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Diabetic retinopathy can progress rapidly without much warning
Serious retinopathy can be present without any symptoms. Hence periodic eye examinations with
dilated pupil are the only way to detect early diabetic retinopathy and prevent further deterioration of
vision.
Visual loss is irreversible and permanent.
Age of Onset
Recommended time of First eye
examination
Routine min follow up
0-30yrs
Within 5 years of diagnosis
Yearly
>31 yrs
Upon diagnosis
Yearly
During pregnancy
Early in 1st Trimester
Every 3 monthly
Screening Guidelines for detailed eye examination:
Once diabetic retinopathy is diagnosed, patients will require follow up every 4-6 months depending on severity of
diabetic retinopathy. Patients with proliferative diabetic retinopathy and severe macular oedema will require
careful follow up every 2-3 months.
Diagnosis


The best protection against diabetic retinopathy is to have regular eye examination.
To find diabetic retinopathy the ophthalmology looks at the inside of the eye using an instrument
called indirect ophthalmoscope after the pupil is dilated with eye drops.

Procedures like Fundus Fluorescein Angiography are used to assess diabetic retinopathy.

Additional procedures like ultra sound may be required if there is no fundus view. OCT is also done to
measure the thickness of central retina and to look for traction at macula.
Fluorescein Angiography


It is a test where a dye is injected in your arm and a magnified photography of retina are taken.
This helps to classify the retinopathy to record changes in the blood vessels, locate the site of leaks,
presence of neovascularisation, ischemia etc.
 This is important in deciding the mode of treatment and evaluates the treatment result.
 Subsequent angiogram may be necessary to assess the progress of diabetic retinopathy.
Optical Coherence Tomography
It helps to quantify the macular oedema and detect changes not seen on ophthalmoscope which contribute to
visual loss, classify the maculopathy and hence decide on the best mode of treatment and helps in follow-up.
Treatment
No medical treatment is available for diabetes other than strict control of your blood sugar.
Laser
Lasers are widely used in treatment of diabetic retinopathy. It can slow down the progression of diabetic
retinopathy and stabilize vision. Laser is a high beam of light source which is focused on the retina. It helps in
regression of the new vessels in preventing or stopping bleeding and in sealing site of leakage.
Types of laser treatment
1.
Focal treatment
In patient with macular oedema laser is applied to the area of leak to seal it.
2.
Pan retinal photocoagulation (PRP)
 This involves laser application all around the retina. 1000 to 2000 burns are given. This is done in
proliferative diabetic retinopathy.
 Two sittings are required. Sometimes additional laser may be required depending on the condition of
the retina and severity of the retinopathy.
Grid treatment
When there is extensive macular oedema with diffuse leak, laser is applied in a grid pattern to the macula.
3.
Procedure
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Laser is done as an OP procedure. Laser can also be delivered with the patient lying down using the
laser indirect ophthalmoscopic delivery system.
The patient is given topical anesthesia and seated before the slitlamp.
A special contact lens is put on the eye and laser is focused.
The patient should not move his eyes, he should look in the direction advised by the doctors.
The procedure is not painful.
The patient can return home after this procedure and also resume their normal activities.
But patients with proliferative diabetic retinopathy are advised to avoid lifting heavy weight to prevent
bleeding. Those in whom bleeding has already occurred are advised to rest in a propped up position to
facilitate absorption of vitreous hemorrhage.
The effect of laser takes around six weeks to occur.
Some may require additional laser once the hemorrhage has absorbed, as presence of hemorrhage
prevents laser burns being given to all areas of retina.
Side Effects:
Watering of eyes.
Dilated pupils.
Mild headache.
Reduced field of vision.
These are usually temporary but if they worsen they should contact an ophthalmologist immediately.
Vitrectomy Surgery
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It is an OT procedure. In advanced cases vitrectomy surgery is the only option.
In this procedure blood filled vitreous and fibrovascular membranes are removed followed by
endolaser application to the retina.
And if there is retinal detachment silicon oil or gas may have to be injected into the eyes to reattach
the retina.
Vitrectomy is usually done by giving an injection below the eye ball to anesthetize the eye and
immobilize it.
All these procedures are done to stabilize the retinopathy.
Visual improvement after surgery depends on the retinal function.
Hence the surgeries are done under guarded visual prognosis as in most of the cases retina is severely
affected by the retinal pathology.
ANTI-VEGF THERAPY
This is a relatively new modality of treatment which is showing promising results. This consists of an intra- vitreal
injection of 0.1 ml of anti-VEGF (Vascular Endothelial Growth Factor, Avastin and lucentis). This helps to inhibit the
growth of new vessels and thereby stabilize the proliferative retinopathy and neovascular glaucoma not responding
to laser. This is also done in the theatre under sterile conditions as an OP procedure. Reevaluation in form of an FFA
and OCT will have to be done after 1 week and may have to be repeated to assess the effect of treatment. The
injection may have to be repeated after 3 months.
INTRAVITREAL TRIAMCINOLONE
In cases of severe maculopathy, intravitreal triamcinolone injection can be given to reduce the maculopathy. This is
because laser cannot be taken up by a grossly oedematous retina. It is done in the theatre after topical anaesthesia
as an OP procedure. Complications that can occur are raised eye pressure and progression of cataract. Hence IOP
monitoring is necessary after the procedure. Follow up includes OCT evaluation and FFA to assess the effect of
treatment. This is usually followed by laser therapy once the oedema has reduced. At times the IVTA injection may
have to be repeated after 2-3 months. Another option is vitrectomy followed by IVT injection. This is found to have
better results than IVT injection alone. However this is an inpatient surgical procedure.
NEWER SUSTAINED RELEASE DEXAMETHASONE PREPARATIONS ARE AVAILABLE WITH FEWER SIDE EFFECTS OF
CATARACT AND GLAUCOMA AND LONGER DURATION OF ACTION.
INTRAVITREAL ANTI VEGF INJECTIONS ARE USED TO REDUCE THE RETINAL THICKNESS BEFORE LASER IN PATIENTS
WITH DIABETIC MACULAR EDEMA AND PROLIFERATIVE DIABETIC RETINOPATHY WHERE IT HASTENS REGRESSION OF
NEOVASCULARISATION
GLAUCOMA
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Glaucoma is a condition when there is an increase in the pressure of the eye and it damages the optic nerve of
the eye.
It can lead to gradual loss of vision. Glaucoma is a potentially blinding disease which requires life long
treatment.
However glaucoma can occur even with normal intraocular pressure in some people. This is called normal
tension glaucoma.
The front portion of the eye contains a clear fluid called the aqueous humor. A balance between its production
and drainage helps to maintain a constant level of pressure within the eye.
If the drainage area for the aqueous called the drainage angle is blocked, fluid cannot flow out of the eye
resulting in increased pressure and damage to the optic nerve.
If glaucoma is diagnosed early and the patient receives proper eye care regularly further loss of vision can be
prevented.
So a detailed evaluation is necessary and the diagnosis has to be confirmed before treatment is started.
Central vision helps in reading seeing things and also to identify colours.
Peripheral vision helps to see the surrounding things. When damage to the optic nerve occurs blind spots called
scotomas in the peripheral vision develops and usually go undetected until the central vision gets affected.
Early detection and treatment are the keys to prevent optic nerve damage.
Elderly patients, myopic patients and patient with family history of glaucoma, patient with diabetes mellitus,
blood pressure, migraine or headache may develop glaucoma.
There are 2 types of glaucoma
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Primary open-angle glaucoma
Angle closure glaucoma
Primary open angle glaucoma
Open angle glaucoma usually has no symptoms in the early stages and vision remains normal. Usually patient
realizes the vision loss only when it affects the central vision.
Angle closure glaucoma
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It has symptoms like coloured haloes, blurred vision, headache, severe eye pain, redness and nausea.
These patients need immediate treatment and hospitalization in order to reduce pressure of the eye.
Patient having narrow angle between cornea and iris should undergo Yag PI. In this a small opening is made
in the iris so that aqueous fluid can drain into the anterior chamber.
Glaucoma patient are expected to undergo regular eye examination. Eye drops will help to reduce pressure
of the eye.
Surgery trabeculectomy may be required in some condition when the intra ocular pressure is uncontrolled
with medications.
Counseling
There are some changes seen in the pressure of the eye when doctor has done check up. To check whether there is any
damages in the your eye due to this pressure variation, we have to do certain test like applanation tonometry,
gonioscopy,dilated evaluation to see the optic nerve and retina, Disc photo, OCT, Pachymeter, diurnal variation. We
have to do
Non contact tonometry and applanation tonometry- to check the pressure of the eye.
Computerised Field test (C30-2) – to check the field of vision. It is done to evaluate nerve damage which is already
occurred and it has to be repeated every 6 months to assess progression. Glaucoma affects the peripheral field
initially, central field will get affected only in the end stages. Vision test will not reveal the peripheral field of vision
only field testing will show this. It is usually done prior to dilatation.
Gonioscopy- to examine the angle of the anterior chamber. To differentiate between angle closure and open angle
glaucoma which require different treatment. Dilatation should not be performed in suspicious cases (eg: those with
shallow anterior chamber) before gonioscopic evaluation of the angle.
Disc photo- disc is the beginning of the optic nerve. Images of the disc are stored in the computer and comparison
with previous Disc photos is done to assess the progression of damages that have already occurred. This test is
repeated yearly.
OCT (Optical Coherence Tomography) - to scan the cup in the optic nerve and measure its dimensions as well as to
look for thinning in the retinal nerve fibre layer around the disc. This test is repeated in every year.
Pachymetry - is done to measure the corneal thickness. The intraocular pressure recording can vary according to
the thickness of cornea. So thickness of cornea has to be measured for accurate IOP recording
Diurnal variation- diurnal variation in the intraocular pressure is charted and if the fluctuation is greater than 5 mm
it is significant and is an indication to start treatment.The pressure of the eye has to be checked every two hours in
a day as IOP varies throughout the day.
Treatment
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Eye drops, Laser treatment and surgery are methods used to prevent from further damage. In some
cases oral medicines are also used.
Glaucoma is usually controlled with eye drops taken on a daily basis.
These medications decrease eye pressure either by slowing the amount of aqueous fluid produced
within the eye or by increasing the drainage of aqueous.
Glaucoma medication may also produce side effects like stinging, redness, dry mouth, changes in
pulse, heart beat or breathing.
Preoperative Counseling for Trabeculectomy:
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Trabeculectomy is done to reduce the intraocular pressure and not to improve vision.
No visual improvement should be expected after trabeculectomy.
Trabeculectomy creates a new drainage channel for the aqueous fluid to leave the eye.
Following surgery the intraocular pressure may be on the lower side or on the higher side.
If it is on the lower side the eye will patched and if it is on the higher side massage will be given.
If still the pressure does not come down the sutures will be lysed with the help of laser.
Depending on the postoperative status, anti glaucoma medications may have to be restarted.
More frequent reviews may be required following trabeculectomy for monitoring IOP.
Postoperative Counseling for Trabeculectomy:
There are four restrictions to follow after surgery.
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Do not lie on the operated side for five days.
Do not rub the operated eye for 15 days.
Do not take head bath for 15 days.
Do not do any heavy work or strain.
All other routine activities can be done. An eye shield will be required at night for three weeks.
Application of Drops
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Always wash hands with soap and water well before instilling drops.
Only one drop is required.
Atleast ten minutes interval between drops is required.
Frequency of drops should be according to schedule.
Clean the eye in the morning and evening with cotton buds dipped in boiled and cooled water.
Otherwise crusting of the lid margins from the drop instilled in the eyes will occur.
CATARACT
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Cataract is usually the result of ageing just like how our hair turns grey. This can be cured only by surgery;
no medication is effective for this particular eye disease.
Cataract surgery is generally not an emergency but we prefer not to postpone surgery because if the
cataract becomes harder operation will become difficult. Its a slowly progressing disease.
In some types of cataract like hypermature cataract surgery patient is usually advised to undergo surgery
with out today. The cataract may rupture or block the pupil resulting in sudden rise of intraocular
pressure with very severe eye pain. It then becomes an emergency and surgery may also become more
difficulty
Here we are providing latest type of cataract surgery called Key Hole Surgery or Phacoemulsification. In key
hole surgery hospitalization is not required and surgery can be performed without any pain. After 5-6 hrs
they can go back home. Eye drops has to be continued for 2 months after the surgery.
Glass prescription is required for near vision after the surgery. If you are already using glass ,the power of
glass will be changed after surgery
Requirements
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2.
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A-Scan Biometry- This is to calculate the power of intraocular lens which is going to be implanted in your
eye after the cataract is removed.
Corneal Topography- To asses topography of cornea. We can predict postoperative astigmatism if there is
corneal astigmatism. In case of cornea being steeper at any one meridian, the incision can be modified at
the time of surgery to overcome the astigmatism caused by this.
Specular Microscopy- To assess the corneal endothelial cell count prior to the surgery. Intraocular surgery
can lead to corneal oedema. Only if the cell count is normal, can this intracorneal fluid be pumped out. If
the cell count is low corneal oedema can persist leading to bullous keratopathy. In case the cell count is
low, special precautionary measures can be taken to avoid excessive manipulation and thereby
postoperative corneal oedema. In cases of unexplained carneal edema or where we suspect corneal
endothelial lesions, a cell count should be taken.
4.
5.
Patient has to produce Medical fitness certificate for cataract surgery under local anesthesia which
includes atleast the following test like HB,TC,DC,ESR,Urinanalysis,RBS,Blood urea,Creatine,FBS,PPBS etc
Patient has to fix a mutually convenient day foe surgery. Pre operative instructions will be given once the
patient has confirmed the date of surgery.
Lens (IOL) options
Here we are providing three types of IOL options. Each lens has got advantages and disadvantages
1.Rigid lens (Indian made)
It is not a foldable lens. This incision has to be enlarged from 2.8mm (which is sufficient for
phacoemulsification) to 6mm.Reaction after surgery is more and healing will take longer. Glasses can be given
only after one month. The incidence of post capsular opacification is higher.
2. Foldable lens (foreign lens)
Incision will be smaller. It is foldable and reaction will be less, healing will be faster. Glasses can be prescribed
after 2 weeks. The incidence of post capsular opacification is comparatively lesser.
3.
Multifocal lens
Both the above mentioned lenses will require near vision correction and may require some power for distance.
However multifocal lens correct for both near and distance so that routine activities cab be performed without
glasses. However glasses may be required for functioning the vision or in case of prolonged reading. Moreover
time is required for the brain to adjust to those lenses.
Without spectacles the patient will have both near and long vision
Pre- operative instructions
For the first 5 days after the surgery there are only three restrictions to be followed
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Do not take head bath
Do not rub the operated eye
Do not lie down on the operated side
There are no others restrictions: you can talk, attend to telephone calls, watch TV, bend down, eat food of your
choice, travel by any mode, can read news paper etc
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One week before the surgery patient should start anti-inflammatory medicine(ie voveran ophtha/flur 4
times daily)
And two days before antibiotic eye drops has to be instilled.
If the patient is using anticoagulant such as ecosprin/clopilet etc it should be stopped before 5 days after
discussing with the cardiologist.
The patient MAY report to the clinic the day before surgery FOR CLEARING AY DOUBTS PERTAINING TO
THE PROCEDURE. On that day they should bring all the medicines and physical fitness certificate. Patients
are recommended to obtain the physical fitness certificate at the earliest. He /she should perform all the
relevant investigations and see the Physician immediately after the pre op instructions are given. Physical
fitness should be kept ready before patient comes for eye lash trimming.
He /she should not wait till the day before surgery to get the fitness certificate. Sometimes the physician
may need a week time or more to give the certificate depending upon the patients condition.
Pre operative counseling
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Patient has to wash their face 5 or 6 times before surgery with an antiseptic soap like dettol, savlon etc
On the day of the surgery dilating drops are instilled at 15 minutes interval 3 times one hour before the surgery.
Can take regular breakfast and medicine before coming to hospital
Should remove their gold ornament or wipe off kumkum or bindhi from your forehead before entering the
operation theatre.
Report the hospital on the reporting time.
First test dose of anesthetic agent is given on the arm.
Here we are providing 2 types of anesthesia one is topical anesthesia that is applying xylocaine gel applied on
the surface of the eye which is to be operated
If the patient is uncooperative, local anesthesia is given by an injection under the eye to be operated.
Actual surgery will take only 15-20 minutes.
You have to change from your normal dress to theatre dress.
Ladies should have their hair plaited on both sides.
BP and sugar will be checked.
Do not move your eye during the surgery and you should look in the direction on doctor asks you to do.
Your face will be covered except your eyes.
Should ask the patient whether he /she is having any neck problem or any other difficulty. Patient may be
require to lie down inside the operation theater for half an hour to one hour which may make it difficult for him
or her to lie still on his back.
Some patients may have uncorrected distant vision but they may require glasses for near vision. Some may
have uncorrected near vision. Such patients will require glasses for distant vision.
During the surgery if doctor use any extra consumables or medicine, then patients need to pay additional
charge.
Complications
During local anesthesia:
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Most of the time there is no problem. The eye has to be kept still during the block. If the eye is moved, damage
may occur to the eye or the blood vessels and nerves around the eye.
Mild bleeding outside the eye is not of much consequence. However if the bleeding is severe, surgery may have
to be postponed. Rarely if the injection enters the blood vessels around the optic nerve, it may result in
seizures and even death.
During surgery:
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Need to convert into a larger wound. In certain difficult situations for eg:- hard nucleus, poor patient co
operation, significant subluxation etc the small Key hole may have to be converted to large key hole for the
sake of patient safety.
Sometimes the wound may need to be sutured. This is to strengthen the wound and will no way affect
the postoperative rehabilitation.
Chance of damage to PC/Zonules is there if the patient moves suddenly. In the event of a PC
rent/Zonular damage or unstable bag there is a possibility of postponing IOL implantation or IOL may have to
be placed in a different location.
Eg; ACIOL
There is a chance of the lens slipping into vitreous if there is damage to the posterior capsule. In such
cases re-surgery may be required.
Small pupil: In some eyes pupils may not dilate fully or may constrict during surgery. In such cases
other instruments may have to be used to dilate the pupil.
After Surgery
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In case of very hard cataract there may be swelling in the cornea which may delay complete visual recovery.
This usually clears by 1-2 weeks
Some patients may have more than usual reaction in the eye, in such a case drops may have to be used more
frequently.
Infection is one of the most dreaded complications of surgery. It can result in loss of the eye. It can occur in 1-3
out of 1000 patients. All needed precautions are taken prior to the surgery.
For some patient there is a chance of a membrane forming behind the lens, 1-2 years following the surgery.
You need to undergo YAG laser capsulotomy where opening is made in the centre of the posterior capsule to
clear the visual axis.
If there is any machine error in calculating the IOL power you may need to wear a high power glass. This can
happen very rarely.
Last but not the least, the patient must understand that the final visual recovery (however perfect is the cataract
surgery) will depend largely on the functioning of his or her retina and optic nerve. Those patients with prior retinal
damage or optic nerve damage have guarded visual prognosis. Then visual recovery will depend solely on the
functional status of the retina and optic nerve.
Post operative counseling
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The operated eye will not be patched if topical anesthesia is given.
Visual recovery will depend on the retinal potential.
Glass are required for near vision, after 2 weeks from the date of surgery, glass prescription will be given in case
of foldable lens and 1 month in case of rigid IOL.
The operated eye will be patched if local anesthesia is given. Patch will be removed from the operated eye on
the same day after the patient comes to the clinic for check up.
Clean the eyelids in the morning and evening and follow application of medicines as per the instructions.
Patients must contact the clinic if they have a doubt or any adverse reaction.
Eye ointment should be avoided on the morning of reiview visit as well as the previous night.
Allergy may develop in some patients in such situation they can immediately contact us.
After surgery dryness may occur. For this lubricant eye drops has to be used.
They should wash their hands before and after instilling drops. Take care so that the tip of the bottle does not
touch the eye.
To avoid infection and inflammation after the surgery drop has to be used for 2 months.
You should not wipe your eyes by using saree, towel, handkerchief etc.