Lecture 2 (Dr. Wajida Saad Bunyan)
Examination Techniques
History
Personal history :
- Age.
- Occupation: farmers and people who work outdoors are more liable to certain
conjunctival lesions e.g ptrygium because they are exposed to the harmful ultraviolet
rays of the sun and to air pollution.
- Personal habits: alcoholics and tobacco smokers are liable to toxic amblyopia
(retrobulbar neuritis) .
Past history :
General disease: diabetes , hypertension, renal disease and arthritis are diseases that may be
of importance and could be related to the patient's problem.
Medical history: previous medication e.g corticosteroids, antiglaucoma drugs,
antidepressants.
Ocular history of: trauma, previous operation, recurrent attacks of pain and redness with
drop of vision may be suggestive of acute glaucoma or irido – cyclitis.
Family history of :
Cataract
High myopia
Glaucoma
Retinal degeneration
Positive consanguinity in hereditary diseases
COMPLAINT
VISUAL COMPLAINTS
Diminution of vision
Onset: may be sudden (e.g. central retinal artery occlusion) or gradual (e.g. senile cataract).
Duration: the complaint of the patient may be recent or long – standing.
Pain: Diminution of vision may be painless as in cataract or associated with pain as acute
glaucoma and iridocyclitis.
Redness: may be present or absent.
Course: may be stationary or progressive.
Blurred vision : as in error of refraction
Decreased vision could be more at night in immature senile cortical cataract and retinitis
pigmentosa or more during the day as in nuclear cataract
Field defects :
The patient may complain that he cannot see in certain areas of the visual field, which may be
Uniocular as in retinal detachment, glaucoma and optic nerve lesions.
Opsias:
Metamorphopsia: objects appear distorted as in macular lesions and retinal detachment.
Macropsia: objects appear bigger in size
Micropsia: objects appear smaller in size
Photopsia: patient sees flashes of light. It could be due to retinal detachment, retinitis, or choroidits. It
is due to mechanical stimulation of the rods and cones or due to inflammation.
Chromatopsia: colored vision
Cyanopsia: blue vision as after nuclear cataract removal.
Xanthopsia: yellow vision as in digitalis toxicity
Visual hallucinations: in lesions of the visual areas.
Scintillations: colored lines seen in the aura of migraine.
Diplopia is a double vision
It could be monocular as in subluxation of the lens and iridodialysis or binocular as in paralytic squint.
Musca volitantes
The patient may complain of seeing moving or flying insect – like floaters in front of the eye. They
move with the eye movement and appear more on a white surface. Musca may be due to:
Vitreous floaters as in high myopia.
-
Vitreous hemorrhage as following trauma and in proliferative diabetic retinopathy.
-
PAIN
The character of pain differs from one disease to the other, it could be:
Throbbing : as in stye, hordeolum internum
Bursting : as in acute congestive glaucoma
Neuralgic : as in herpes zoster
Dull – aching : as in iritis , corneal ulcer
PHOTOPHOBIA
Inability to open the eye facing light. This is a common complaint that may be due to:
-Keratitis , iritis
Corneal ulcers and foreign bodies.
-
DISCHARGE
Depending on the type and severity of conjuncitivitis, the discharge may be:
Mucopurulent : as in mucopurulent conjunctivis
Purulent: as in purulent conjunctivitis
Mucous: as in allergy
Watery: as in viral conjunctivitis
REDNESS
Due to conjunctival hyperemia. There are two types of redness:
Painless redness (conjunctival injection only):
Conjunctivitis
Subconjunctival hemorrhage
Painful redness (ciliary injection with or without conjunctival injection):
Corneal ulcer or foreign body
-
-Acute or subacute attacks of closure glaucoma.
-Iridocyclitis.
Episcleritis
-
Endopthamitis
-
WATERING OF THE EYE :
Epiphora
Watering of the eye due to obstruction of the lacrimal passages.
History of dacryocystitis.
Lacrimation
Watering of the eye due to increased production of tears
LEUKOCORIA
White colored pupil, the most common cause is cataract. In children with
leukocoria, retinoblastoma must be excluded.
PROTRUSION OF THE GLOBE ( PROPTOSIS)
Painful or painless
With or without diminution of vision.
Onset sudden or gradual
May be related to trauma.
Presence of symptoms and signs of inflammation
History or symptoms of thyrotoxicosis
SQUINT
Disturbance of the parallel relation between the axes of the 2 eyes.
COMMON CHILDHOOD COMPLAINTS
Preverbal children cannot complain of pain or defective vision. It is the mother who first notices any
defect in appearance or defective vision. Examination of an infant or a child requires general
anesthesia.
The most common complaints are:
1.Squint
Onset: may be shortly after birth or a few years later
History of trauma or fever often precede the squint
History of previous surgical operations to correct the squint.
2.Leukocoria:
Immediately after birth or later in childhood
May be unilateral or bilateral.
The commonest causes are cataract and retinoblastoma.
3.Epiphora: Due to incomplete canalization of the lacrimal passages which is commonly unilateral
and causes unilateral conjunctivitis and discharge.
4.Proptosis: congenital causes and others.
5.Increased corneal diameter with pain, photophobia and watering
of the eye: is often due congenital glaucoma (buphthalmos).
VISUAL ACUITY TEST
The visual acuity chart: Landolt's chart also called broken ring chart is used.
The patient sits at a distance of 6 meters from the chart.
The lowest line that can be read is recorded. For example, if vision is 6/24, it means that the patient
can see at 6 meters what a normal person can see at 24 meters.
If the patient cannot see the largest ring (6/60) the patient gets closer to the chart ( one meter at a time )
until he sees the largest ring (5/60, 4/60 etc).
If the patient cannot see the largest ring at a distance of one meter, ask him to count fingers.
FUNDUS EXAMINATION
Fundus examination is done after dilating the pupil with a short acting mydriatic as tropicamide or
cyclopentolate. In infants, atropine eye ointment should be used to dilate the pupil to avoid systemic
absorption leading to toxicity. Examination of the fundus allows the examiner to comment on the optic
disc, macular area, periphery of the fundus and the state of the retinal vessels.
The fundus is examined using:
Direct ophthalmoscope:
A hand held instrument that gives a magnified view allowing detailed
examination of the optic disc and macular area. The field of examination is small and not suitable for
examination of the periphery of the fundus.
Indirect ophthalmoscope:
with the aid of a + 20D or +30 D lens, the central and peripheral
fundus can be examined. The field seen using the binocular indirect ophthalmoscope is large and gives
a stereoscopic view of the fundus but the magnification is small
Retinal function tests:
When visualization of the fundus is obscured by a dense opacity as in mature cataract, or vitreous
hemorrhage, the function of the retinal periphery can be roughly estimated using the light projection
test
.
Light projection:
a strong focused light is used at a distance of 50 cm in a dark room. It is
projected to a single eye from the 4 different quadrants to which the patient should rapidly
and precisely point. This test gives an idea about the rod function in the retinal periphery.
Macular function tests:
visual acuity, color and form sense are the main macular function test. In
opaque media, the color and form may be tested as follows:
Color test :
A colored light is projected from a torch or using the color filters of the slit lamp, one eye at a time,
with the other eye carefully covered. If the patient can distinguish between red, and green, then color
sense is intact giving a fair idea as to the functions of the cones.
INTRAOCULAR PRESSURE (IOP)
The normal intraocular pressure ranges between 10 mmHg to 22 mm Hg. Any rise above 22 mm Hg
is considered a high IOP.
The normal IOP:
A fixed value cannot be given, for even in the same person, it is variable with the time of the day (
diurnal variation )
The difference between the IOP in both eyes is usually less than 4 mm Hg.
The diurnal variation does not usually exceed 4 mm Hg.
Gently press on the sclera by one index finger and feel the rebound by the other finger. This gives a
rough idea about the IOP. Very high or very low IOP can be felt.
Indentation tonometry (Schitz)
Based on the principle that a plunger will indent a soft eye more than a hard eye. The amount of
indentation is measured on a scale and then the reading is converted into mmHg
Applanation tonometry ( goldman):
Applanation tonometry is based on the principle of flattening an area of the cornea with a double prism
that has a diameter of 3.06 mm.
PERIMETRY
Perimetry is assessment of the visual field. It is important in the diagnosis and management of
glaucoma, optic nerve lesions, and lesions affecting the visual pathway.
The visual field extends 60 nasally 90 temporally, 50 superiorly, and 70
1.Kinetic perimetry, which involves moving a stimulus of known luminance ( intensity of light) from
the periphery towards the center to outline an isopter
•
2.Static perimetry, which present the patient with a fixed grid of points covering the important
areas of the field.
Methods of Kinetic perimetry :
Confrontation test :
It is a rough method suitable for the detection of large field defects involving the vertical half of large
field (hemianopia) or the horizontal half (altitudinal) .
Goldmann perimeter :
This is a hemispherical dome with a chin rest for the patient and the examiner can observe the
patient's fixation from a telescope.
Types of field defects:
A field defect is an area not seen by the patient.
Scotoma: it is a blind island in the sea of vision.
An absolute scotoma is an area of the visual field where there is total loss of light sense.
A relative scotoma is caused by partial visual damage where some targets can be seen ( large size or
more bright) .
A positive scotoma is one felt and reported by the patient while a negative scotoma is discovered
during field examination.
The blind spot is a negative absolute scotoma
Hemianopia: a large field defect involving the vertical half of the field respecting the vertical
meridian.
Altitudinal field defect: a large defect involving the horizontal half of the field respecting the
horizontal meridian.
Peripheral contraction: loss of the peripheral field of vision.
GONIOSCOPY
It is the technique of examining the angle of the AC. Normally the angle is
not seen on external examination. In this technique a contact lens
( goniolens ) is placed on the cornea and the angle is examined with the
slit lamp.
FLUORESCEIN ANGIOGRPHY
Fluorescein angiorgraphy is a useful investigation used to evaluate a great variety of retinal
disorders that affect the retinal vascular system or the choroid.
ELECTROPHYSIOLOGIC TESTS:
The electroretinogram (ERG)
ERG is an important tool in diagnosing and managing hereditary retinal disease as night blindness
and retinal degeneration such as retinitis pigmentsa ( RP)
Electrooculogram (EOG)
EOG is an electrical recording based on the standing potential of the eye were the cornea is
negative in relation to the retina. It records ionic and metabolic changes in the retinal pigment
epithlium (RPE) as well as in the neuroretina.
Visual evoked potential (VEP)
Light stimulation of the retina produces waves recorded over the occipital lobe. It is use in :
Measuring visual acuity in children
Diagnosis of optic neuritis.
Diagnosis of unilateral disease of the visual pathway.
OPTICAL COHERENCE TOMOGRAPHY(OCT)
It is useful in studying the thickness of the retinal nerve fiber layer in glaucoma and in the study of
macular diseases.
ULTRASONOGRAPHY
Ultrasonography a non- invasive diagnostic tool that allows examination of the ocular structures in
the presence of media opacities such as opaque cornea, cataract or vitreous hemorrhage.
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