OCULAR
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SYMPTOMATOLOGYDIMINUTION OF VISION
Characterization of the loss of vision should
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include:
1. Duration
2. Progression: steadily worsening, improving or
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static
3. Pattern: constant, intermittent, more for
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distance or near, episodic or periodic; and4. Associated symptoms such as pain, redness,
watering, photophobia, photopsia, floaters,
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diplopia, presence of a positive or negative
scotoma or peripheral field defect.
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CAUSES OF GRADUAL PAINLESS
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VISION LOSS? Refractive error
? Cataract
? ARMD
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? Refractive error? Chronic (primary) open-angle glaucoma
? Diabetic retinopathy
? Drugs, toxins or nutritional deficiency
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? Hereditary retinal dystrophies
? Cerebrovascular disease
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? Papilledema? Compression of optic nerve or optic pathway
CAUSES OF GRADUAL PAINFUL
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VISION LOSS? UVEITIS
? OPTIC NEURITIS
? TRAUMA
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SUDDEN PAINLESS
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DOV
? RETINAL DETACHMENT
? VIT HAEMORRAGE
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? CRVO? CRAO
? GAINT CELL ARTERITIS
? NAION
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ANOMALIES OF OCULARMOTILITY
Disturbances of the extra ocular muscles may
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manifest as:
1. Eyestrain OR Asthenopia
2. Binocular Diplopia
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ASTHENOPIA
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Weakness or fatigue of the eyes commonly following
prolonged close work but may also occur after extended
viewing at a distance such watching TV.
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Aching/burning of eyes?
Heaviness of eyelids
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?Headache
?
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`Doubling' of letters
Seen in:
? Insufficiency of convergence
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? Phorias or other extraocular muscle imbalances? Uncorrected refractive error
? Uncorrected refractive correction especially of
astigmatism, or early presbyopia.
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BINOCULAR DIPLOPIA
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? Subjective impression of two images of the same
object seen by the patient when both eyes are
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open, but one image disappears on closing eithereye
? Occurs due to the inability of the two eyes to
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move together synchronously such that their
foveas are both directed towards a target.
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? Seen in:? Extra ocular muscle paresis
? Restrictive squint
? Displaced globe
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DISORDERS OF OCULAR SURFACE
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? Ocular irritation
? Lacrimation
? Photophobia
? Red eye
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OCULAR IRRITATION
? Sandy or gritty sensation which is generally
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worse in the morning.? The patient may also complain of tiredness of
the eyes or a burning sensation.
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LACRIMATION
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? Reflex increase in the production of tears, as opposed
to epiphora, which signifies an overflow of tears due
to an obstruction to the outflow of tears.
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? Caused by irritation of the ocular surface due to the
presence of a foreign particle, inflammation,
chemical injuries or psychogenic factors.
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PHOTOPHOBIA
?
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Discomfort caused by an abnormal sensitivity to ambient lightconditions.
?
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Due to pain induced by pupillary constriction and ciliary spasmbecause of inflammations at the anterior segment, or
stimulation of the terminal fibres of the trigeminal nerve in the
cornea.
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?Encountered in patients having abnormalities of the corneal
surface or anterior uveitis.
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Mild photophobia 1.Keratoconiunctivitis
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2.Posterior uveitis.3.Some drugs and poisons
which dilate the pupil .
True photophobia must be distinguished from
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'glare' as well as decreased vision in bright light.
GLARE
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Excessive awareness of light could be due toconditions
allow excess light to enter the eye such as aniridia
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and ocular albinism,
produce excessive irregular scattering of light in
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the eye such as a posterior sub-capsular cataract.--- Content provided by FirstRanker.com ---
Decreased vision in bright light, due toconditions such as posterior subcapsular
cataract, congenital cone dystrophy and other
central macular disorders may also be mistaken,
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for photophobia because of the occasionallyreported symptom of having to partly close the
eyes in bright light.
RED EYE
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Prominent symptom
1.Anterior uveitis, 2.Keratitis, and
3.Acute angle-closure glaucoma.
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The distinguishing features between
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conjunctivitis, iritis and glaucoma are given in
the following table:
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CONJUNCTIVITISINFECTIOUS
1.VIRAL
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2.BACTERIAL
NON INFECTIOUS:
1ALLREGIC
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2.DRY EYE
2.CHEMICAL REACTION
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4.FOREIGN BODYKERATITIS
INFECTIOUS:
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1.FUNAGAL
2.VIRAL
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3.BACTERIAL4.PROTOZOAL I.E ACANTHAMOEBA
NON INFECTIOUS:
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CORNEAL EROSIONS2.FOREIGN BODY
UVEITIS
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ACUTE ANGLE CLOSURE GLAUCOMA--- Content provided by FirstRanker.com ---
D/D'S OF THE COMMON CAUSESOF A RED EYE
VISUAL PHENOMENA
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Glare
Floaters
Photopsia
Uniocular diplopia
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MetamorphopsiaColoured Halos
Visual Hallucinations
Scintillating scotoma
Coloured vision
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FLOATERS
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? Normal y transparent vitreous gel liquefies and
breaks up, leading to the presence of little particles
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and fibrous strands floating in the vitreousCAUSE
cavity,with age.
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? Debris casts shadows onto the retina.
? Black dots, rings, strands, 'spiderlike' images that
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are more noticeable against a bright backgroundCOMPLAINTS
and 'move' even when the eye is stationary.
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FLOATERS
? Some form of vitreous degeneration and liquefaction
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and are usual y benign and age related; they areINDICATES
also common at a younger age in myopes.
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? Showers of dots or a sudden increase in their
numbers Indicate the formation of a retinal tear
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? Sometimes the onset of new floaters is secondary tovitreous haemorrhage, often caused by advanced
diabetic retinopathy.
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PHOTOPSIA
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? Flashes of light or sensation of flickering lights.
COMPLAINTS
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? Vitreous shrinkage or liquefaction, which causes a pullon the vitreoretinal attachments, irritating the retina
CAUSE
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and causing it to discharge electrical impulses.
? These impulses are interpreted by the brain as
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'flashes'.? Phenomenon is usually benign and age- related, but
could be an indicator of a developing retinal tear or an
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early retinal detachment.
UNIOCULAR DIPLOPIA
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? Early senile cataract:? When light is refracted through wedge shaped areas of
hydration in immature senile cataract, patient sees multiple
images of distant objects such as moon.
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? Subluxated lens : two images of an object, one through
aphakic area and other through phakic zone.
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? Large iridotomies, if not below the upper lid may also causeshadowing or uniocular diplopia.
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UNIOCULAR DIPLOPIA
? Folded- over retinal flap in giant retinal tears is a rare
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cause.
? One image is seen by the macula and projected straight
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ahead. Other image is due to stimulation of the displacedretina and is projected to the point in the visual field
normally subserved by that region of the retina.
METAMORPHOPSIA
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? Patient perceives objects to have an altered,
irregular contour or shape.
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? Reviewed for any changes using an Amslergrid,which tests central 10 degree of vision.
? Central serous choroidopathy,ARMD,diabetic
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Seen in macular edema,macular hole
? Micropsia when ordinary, everyday objects
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Variant look smaller than normalseen in central serouschorioretinopathy due to separation of retinal
elements by collection of SRF.
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COLOURED HALOS
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? Rainbow coloured rings around lights at night.
? Acute angle closure glaucoma,cataract,corneal
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Seen in edema,mucus on surface of the conjunctiva.? Occurs due to prismatic dispersion of light bought
about these conditions.
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COLOURED HALOS
? Occurs due to accumulation of fluid in the corneal epithelium &
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to alterations in the refractive condition of the corneal lamellae.? Halos induced by corneal diseases & early cataractous changes
in the lens may be differentiated by the Fincham's test.
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? A stenopaeic slit is passed before the eye across the line of
vision. glaucomatous halo remains intact but diminished in
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intensity whereas,a lenticular halo is broken up into segmentswhich revolve as the slit is moved.
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VISUAL HALLUCINATIONS
? Objects,shapes or lights seen by patients which are not
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visible to other persons in the vicinity & are fairly
Definition
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specific for disorders involving the cerebral cortex.? 1.Unformed visual hallucination
Types ? 2.Formed visual hallucination
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? Unformed hallucinations consist of seeing distorted
lights as in flashes & spots,lines,objects, or shapes & are
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symptoms of lesions affecting the occipital cortex eg.Migraine & AV malformations.
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VISUAL HALLUCINATIONS
? Formed hallucinations are reported as seeing animals,
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objects, or people & have specific localizing
value,indicating a lesion affecting temporal lobe cortex
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eg. In temporal lobe tumors & epilepsy.? Formed images could represent misinterpretation of
information in brain due to disruption of areas needed to
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process the information.
? Eg. In Charles Bonnet Syndrome, people having a gross
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diminution of vision `see' detailed images.Visual hallucinations can also be due to
transitory or chronic abnormalities in the brain,
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caused by changes like:1. Electrolyte disturbances
2. High fevers
3. Liver or kidney failure
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4. Drugs such as diazepam,alprazolam,LSD--- Content provided by FirstRanker.com ---
SCOTOMATAA scotoma is an area of partial alteration in the
field of vision consisting of a partially
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diminished or entirely degenerated visual acuitythat is surrounded by a field of normal or
relatively well-preserved vision.
Types:
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1. Relative scotoma2. Absolute scotoma
Relative scotoma:
A scotoma in which the visual impairment is not
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complete.
Absolute scotoma:
Absolute scotoma an area within the visual field
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in which perception of light is entirely lost.
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SCINTILLATING SCOTOMATA
In migraine scintillating scotoma of various kinds
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occur.In typical migraine :
Before the attack patient feels unusually well.
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Positive scotoma occurs in the field of vision andwhile obscuring sight it has a peculiar shimmering
character.
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It gradually increases in size until one half of the
field is clouded and fixation point remains
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relatively clear.In dark field, bright spots and fortification spectra
(teichopsia) i.e. rays of various colors is seen
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frequently arranged in zigzags.Homonymous hemianopia usually occurs ( both half
fields are affected )
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In other cases :
Whole field becomes clouded but still fixation point is
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seen momentarily and then becomes obscured untilthe eyes are moved to fresh spot.
Vision usually clears in quarter of an hour.
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Attack is soon followed by violent headache.
Intensified on the side of the head opposite the
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hemianopic field (hemicrania).
Accompanied by nausea and even sickness (
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bilious attack).During the attack numbness in the mouth and
tongue, slight aphasia are frequent and
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copious secretion of urine of low specificgravity.
Attack occurs periodically but vary in number
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and severity.In mild attack and in advanced age the scotoma
may occur without the headache or the headache
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without scotoma.Migraine is attributed to vasomotor changes in
the brain.
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Vasodilatation, associated with a feeling of well-
being, is followed by vasoconstriction,
especially in occipital lobes.
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People who suffer ordinary migraine, have
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attacks in which without any scotoma the
headache is followed by partial paralysis of the
third nerve (ophthalmoplegic migraine) on the
same side as the hemicrania.
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Slight ptosis, diplopia and sluggishness of the
pupillary reactions continue for some hours and
then gradually disappear.
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The paresis is worst and persists longer with
succeeding attacks, and eventually sometimes
becomes permanent.
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Probably most of these cases are not migrainous,
but due to some organic nerve lesion such as
pressure on the third nerve by a distended artery.
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COLOURED VISION
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? Also known as Chromatopsia , is a rare
symptom.
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? Erythropsia (red vision ) occur in some patientsafter cataract extraction if the eyes are exposed
to bright light.
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? Objects look red but visual acuity is not
affected and no permanent damage results.
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COLOURED VISION? Patient should be warned of the possibility
of erythropsia as it is somewhat alarming
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and suggesting of haemorrhage.
? On the other hand some patients report an
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excessive bluish appearance of objectsafter cataract extraction because blue light
was filtered out by the yellowish
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cataractous nucleus before surgery.
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COLOURED VISION
? It is also met with in snow blindness.
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? Occur in some cases during the resolution ofoptic neuritis when the ensuing atrophy is not
complete.
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? In normal people black print will sometimes
suddenly turn deep red owing to strong lateral
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light entering the eye through the sclera.AMBLYOPIA & AMAUROSIS
DEFINITION:
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Partial and complete loss of sight, respectively, in one orboth eyes in the absence of ophthalmoscopic or other
marked objective sign.
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TYPES OF AMBLYOPIA:
1. Unilateral
2. Bilateral
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UNILATERAL AMBLYOPIA
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BILATERAL AMBLYOPIA? Results from physical
? Due to bilateral sensory
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suppression of retinal
deprivation as in bilateral
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image due to sensorycataract or corneal
deprivation , i.E.
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opacities or bilateral high
Amblyopia or abnormal
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refractive error.binocular interaction.
? Due to anisometropia, with
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a unilaterally higher
refractive error
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Bilateral visual loss due to various exogenous toxinswith a normal fundus used to be termed as
"Toxic amblyopia".
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Now more accurately termed as toxic retinopathies orneuropathies.
Occurs in uraemia, meningitis and hysteria.
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BILATERAL AMAUROSIS
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ONSET: Blindness is sudden or rapid (8-24 hrs),
bilateral and complete.
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SEEN IN:1. Acute nephritis especially complicating pregnancy.
2. After scarlet fever.
3. Chronic renal disease.
FUNDUS: No changes unless there is coincident
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hypertensive retinopathy.
Vision improves in 10-18 hrs and is fully
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restored in about 48 hrs.In uraemic amaurosis the pupils are dilated but
generally react to light showing that the lower
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centres are not affected .The condition is probably due to circulation of
toxic material, which acts upon the cells of
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visual centres.In cases occuring during pregnancy , there is
usually eclampsia.
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AMAUROSIS FUGAX
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DEFINITION:
Transient monocular blindness caused by temporary lack
of blood flow either to the brain or retina.
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Occurs as a result of emboli from plaques in the carotid
artery.
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These block an artery for a while and then move onresulting in a loss of vision for the duration of blockage.
? Onset is acute and the episode lasts for
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several minutes.
? Sudden loss may appear like a curtain
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falling from above or rising from belowand vision may be completely absent at
the height of the attack.
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? Recovery occurs in the same pattern.
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NIGHT BLINDNESS
Occurs in:
1. Pigmentary retinal dystrophy
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2. Xerophthalmia3. Cirrhosis
Attributed to interference with the functions of
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the retinal rods.COLOUR BLINDNESS &
ACHROMATOPSIA
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TYPES:
1. CONGENITAL
2. ACQUIRED
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a)PARTIAL- RELATIVE SCOTOMATA
B)COMPLETE- DISEASE OF OPTIC Nerve
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In most diseases of retina & choroid, changes in colourperception affect mostly the blue end of the spectrum.
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Slight diminution in acuity of perception of these
rays is caused normal y, owing to their physical
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absorption, by the increase of amber pigment in
the nucleus of the lens (blue blindness).
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Seen in sclerosing lenses(black cataract).Congenital colour blindness:
TOTAL
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PARTIAL
Rare
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Seldom discoveredNystagmus & central
Subjects compensate scotoma.
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for their defect by
attention to shade &
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textureSpectrum appears grey band like the normal scotopic
spectrum, seen with maximum brightness at 510
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microns.
Caused by a central
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COLOUR BLINDNESSInherited condition- X-linked recessive
Due to absence of one of the photopigments
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normally found in the foveal cones.
Red-green cases fall into two chief groups:
1. Protanopes
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2. DeuteranopesProtanopes:
Red end of the spectrum is much less bright than for
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normal people.Shortened spectrum(red end).
Deuteranopes:
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Green sensation is defective.Both have dichromatic vision.
Defects may not be complete & these cases are
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called protanomalous & deuteranomalous,respectively.
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NON-ORGANIC
`FUNCTIONAL' VISUAL LOSS
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Either due to:
1. Wilful `blind' behaviour (malingering)
2. Subconscious expression of non organic signs
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& symptoms of defective vision (hysteria).MALINGERS
HYSTERIA
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Involved with some form of
Little or no insight into their
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financial gain in the form of an infirmity & may sometimesinsurance claim, financial
display a complete lack of
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compensation, employement
concern over their incapacitating
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benefits, an excuse to avoidsymptoms ( la belle indifference)
examinations.
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? Most common presentation:
1. Decreased visual acuity in one or both eyes.
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CONDITIONS WHICH PRODUCE VISUAL LOSSWITH A NORMAL FUNDUS