Trans 003 Acute Non - Traumatic Vision Loss... Flashcards
1
Q
❛ sit on the outside edge of the eyebrow away from the nose in the orbit. This gland produces the watery part of the tears. ❜
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Lacrimal glands
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❛ make the oil that becomes another part of the tear film. ❜
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Meibomian glands
3
Q
Behind the cornea is a fluid filled space called?
The fluid inside the anterior chamber is!
A
Anterior chamber
aqueous humor
4
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The aqueous humor drains from the eye via the
A
Trabecular meshwork
5
Q
❛ are attached to the capsule holding the lens, suspending it from the eye wall ❜
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zonules
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❛ lies between the lens and the back of the eye. ❜
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A jelly like substance fills this cavity palled?
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Vitreous cavity
Vitreous humour
7
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The light sensitive tissue lining the back of the eye?
A
Retina
8
Q
Macula vs peripheral retina
A
❛ A tiny but very specialized area of the retina called the macula is responsible for giving us our detailed, central vision. The other part of the retina, the peripheral retina, provides us with our peripheral (side) vision. ❜
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9
Q
Photoreceptors Na cons & Rods differentiate
A
❛ The retina has special cells called photoreceptors. These cells change light into energy that is transmitted to the brain. There are two types of photoreceptors: rods and cones. Rods perceive black and white and enable night vision. Cones perceive color, and provide central (detail) vision. ❜
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Transient vs persistent visual loss
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❛ Acute vision loss can be transient (lasting <24 hours) or persistent (lasting >24 hours). ❜
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,
11
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❛ Transient and Unilateral
• Due to decreased blood perfusion of the optic nerve and retina
• Associated usually with carotid artery disease ❜
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❛ 1.AMAUROSIS FUGAX ❜
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12
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Causes of amaurosis FugaX
A
❛ Can be from:
o Emboli (see picture) o Hypercoagulable state o Arteritis o Recreational Drug Use ❜ — Page 2
13
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Symptoms criteria for amaurosis fugax
A
❛ Painless, monocular vision loss symptoms after seconds to minutes
o Darkening of vision
o May have presyncopal symptoms ❜
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14
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❛ Transient bilateral
• (bilateral) optic disc swelling from increased intracranial pressure → usually from tumors Swelling of the optic nerve that connects the eye and the brain ❜
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Papilledema
15
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Symptom criteria of papilledema
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❛ Symptom criteria o Transient vision loss lasting seconds and precipitated by postural changes o Headache o Nausea o Vomiting o Pulsatile tinnitus o Double vision ❜ — Page 3
16
Q
Aka bow’s Hunters syndrome
❛ Due to a temporary loss of the blood flow from the vertebral artery to base of brain
• Occurs when rotating the head and having this artery “pinched off” due to an abnormal spur or ligament or presence of intravascular plaques ❜
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❛ VERTEBROBASILAR INSUFFICIENCY ❜
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17
Q
❛ Transient and Bilateral
• Symptom criteria o Small area of visual loss which may expand o Zigzagging colored lines o Shimmering characteristic o May cause hemifield vision loss ❜
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Migraine aura
18
Q
❛ The narrowing or closure of the anterior chamber angle (from pupillary block), resulting in increased IOP With subsequent damage to the optic nerve ❜
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Acute
Angle glaucoma
❛ Normally, aqueous humor drains out of the anterior chamber via Schlemm canal in the anterior chamber angle. In ACG, this flow is impeded, and the IOP rises from a normal range of 10 to 21 mm Hg to 50 mm Hg or higher. ❜
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19
Q
❛ Symptom Criteria o Bedewed Cornea o Mid dilated pupil o Shallow anterior chamber o Conjunctival injection o May have anterior chamber inflammation ❜
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Which symptom
A
Acute angle glaucoma
20
Q
❛ Patients report blurred vision and rainbow-colored halos around lights. Clinical findings include tearing, perilimbal injection (“ciliary flush”), a cloudy (“steamy”) cornea, a nonreactive mid-dilated pupil, anterior chamber inflammation, and an increased IOP. Using a penlight or slit-lamp microscopy, the anterior chamber may appear shallow. ❜
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Acute angle glaucoma
21
Q
Principles of management of acute angle glaucoma
A
❛ PRINCIPLES OF MANAGEMENT o Lower IOP with antiglaucoma medications
o Do laser iridotomy
o Consider trabeculectomy for uncontrolled IOP increase ❜
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22
Q
❛ Intumescent (thick) lends causing the narrowing or closure of the anterior chamber angle (from pupillary block), resulting in increased IOP ❜
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Phacomorphic glaucoma
23
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❛ Symptom criteria o Intumescent lens o Shallow anterior chamber o Conjunctival injection ❜ — Page 5
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❛ PHACOMORPHIC GLAUCOMA ❜
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24
Q
❛ is a complication of the immature and the mature stages of cataracts where the lens absorbs a lot of water. The lens swells with numerous pocket of water vacuoles. ❜
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❛ The patient complains of rapid drop of vision. Pain can occur if the swollen lens blocks the pupil ❜
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❛ Phacomorphic Glaucoma ❜
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❛ PRINCIPLES OF MANAGEMENT ❜
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Of phacomorphic glaucoma
❛ Medical management to control increased IOP
o May do laser iridotomy
o Definitive management is removal of the lens ❜
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❛ Separation of the retina from the choroid
* Subretinal fluid collects, elevating the retina above the underlying choroid
* “Curtain-like” BOV; painless
• More common in long eyeballs (myopes) ❜
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Retinal detachment
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Types of retinal detachment
❛ RHEGMATOGENOUS, TRACTIONAL AND EXUDATIVE ❜
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What type of retinal detachment ❛ requires surgical procedure to seal the whole or tear ❜
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❛ Rhegmatogenous retinal detachment ❜
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What type of retinal detachment ❛ needs surgery to remove the traction usually cause by fibrous bands seen in the end stages of diabetic retinopathy ❜
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❛ Tractional retinal detachment- ❜
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What type of retinal detachment ❛ requires treating the cause of exudation and it is just usually medical ❜
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❛ Exudative retinal detachment- ❜
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❛ • Persistent and (usually) unilateral
* Acute, Painless vision loss
* Decreased retinal perfusion due to an arterial occlusion due to:
o Emboli o Atherosclerosis o Thrombus o Arteritis
• “Cherry red spot” ❜
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Retinal artery occlusion
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❛ • PRINCIPLES OF MANAGEMENT
o Embolic workup which includes Doppler ultrasonography and echocardiography
o Control IOP increases
o Perform maneuvers that vasodilate (ie brown bag)
o Thrombolysis an option
o PRP lase of ischemic areas
o Consider antiVEGF injection ❜
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Retinal artery occlusion
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❛ • Persistent and (usually) unilateral
* Acute, Painless vision loss Secondary to venous statis causes edema, hemorrhage and possible ischemia Loss of vision ranges from severity from partial field loss to profound loss of vision
* Due to:
o Changes in vessel wall (Atherosclerosis) o Alterations of the blood (Hypercoagulable state) o Stasis of blood flow (anatomical) And rarely collagen vascular disease ❜
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❛ RETINAL VEIN OCCLUSION ❜
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❛ • PRINCIPLES OF MANAGEMENT
o Ophthalmology consult
o Anti-vascular endothelial growth intravitreal injection for macular edema
o PRP Laser of ischemic areas
o Dexamethasone implant
o Intravitreal Triamcinolone ❜
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Retinal vein occlusion
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❛ • Refers to leakage of blood or blood products from a retinal vessel around and into the vitreous gel
* Painless loss of vision
* Caused by blood products from normal or abnormal retinal vasculature
• Can occur in isolation or secondary to many underlying ocular and systemic disease ❜
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❛ VITREOUS HEMORRHAGE ❜
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Possible causes of vitreous hemorrhage
❛ • POSSIBLE CAUSES:
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o Proliferative Diabetic Retinopathy
o Avulsed vessel
o Breakthrough bleed from age degeneration
o Prior retinal vascular occlusion
o Traumatic ❜
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Principles of management : vitreous hemorrhage
❛ o Know the cause of the vitreous bleed and address the root
o Use the other eye for clues
o Ocular ultrasound is very useful
o Pars plana vitrectomy to evacuate the blood is an option ❜
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❛ • Persistent and (typical) unilateral
* Most often seen in middle aged women
* Good VA early on
* Progressive BOV
* Associated with pain on eye movement
• Causes include demyelinating disease (eg. Mutiple sclerosis), infection (eg, Syphilis, Lymed disease, viral infection) and granulomatous disease (eg, sarcoidosis). ❜
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❛ OPTIC NEURITIS ❜
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❛ • Symptom Criteria
o Progressive vision loss typically over the course of day
o Reduced perception of light intensity and color brightness
o Pain with extraocular movements
o May have neurologic symptoms such as weakness or tingling ❜
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Optic neuritis
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❛ modularity of choice for visualising the optic nerve. Typically findings are most easily identified the retobular intraorbital segment of the optic nerve which appears swollen with a high T2 signal. ❜
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MRI
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❛ • Occurs secondary to low perfusion
• May involve anterior or posterior of optic nerve ❜
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❛ • Most often seen in older patients with vascular risk factors ❜
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❛ ISCHEMIC OPTIC NEUROPATHY ❜
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❛ Anterior Ischemic Optic Neuropathy- ❜
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Vs ❛ Posterior Ischemic Optic Neuropathy ❜
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❛ Anterior Ischemic Optic Neuropathy- idopathic often associated with multitude of risk factors including artherosclerotic disease, hypertension, diabetes, smoking, sleep apnea, amioderone inhibitors and phospho diesterase inhibitors.
Posterior Ischemic Optic Neuropathy – occurs in abdominal cardio thoracic or spine surgeries possibly brought about by the decreased blood flow due to intra operative hypo tension, anemia or assuming the Trendelenburg position. ❜
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Fundoscopy findings if arteritic AION vs non arteritic AION
non arteritic AION:flame shape peri papillary hemorrhage
arteritic : pale swollen optic disc with a peripapillary cotton wound spot or exudate
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Review figure 33
Review figure 33 page 8
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❛ • Symptom Criteria o Visual field deficits o Headache o Weakness o Numbness o Dysarthia o Aphasia o Dysphagia ❜
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Which disease
Stroke
46
Principles of Mx in stroke?
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❛ • PRINCIPLES OF MANAGEMENT
o Neuroimaging
o Referral to Neurologist
o Map Visual field deficits with perimetry
o Lifestyle Modification ❜
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What milestone? Can fix and follow a light source, face or large colorful toy.
Very soon after birth
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Fixation is central, steady and maintained, can follow a slow target and converge preference of looking at face
I month
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Binocular vision and eye coordination, eyes follow a moving light or face
3 months
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Reaches out accurately
For toes
6 months
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Picture matching
2 years
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Snellen chart matching
5 years old
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20/20 is achieved between
3-5 years
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Clues of poor visual development
❛ • Should not persist after more than 4 months of age:
o Disconjugate eye movements Disconjugate, ibig sabihin, di sabay yung galaw o Skew deviation Meaning deviated: either inward or outward o Tonic downward deviation of both eyes Means jerky movement, hindi smooth
* Wandering eye movements
* Lack of response to familiar objects/faces
• Nystagmus ❜
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Oculodigital reflex?
❛ Is when you might notice those children, they tend to poke their eye. They do this because they elicit some light reflex when they do that, so, naaaliw sila, no. But it is a sign that there is poor visual development ❜
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❛ • BOV that is not directly due to any structural abnormality of the eye or the posterior visual pathway
• Often unilateral
• caused by abnormal visual experience early in life …resulting from one of the ffg: Strabismus or a misalignment Anisometropia or high bilateral and refractive errors or stimulus deprivation ❜
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Amblyopia aka lazy eye
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❛ is responsible for more unilaterally reduced vision of childhood onset than all other causes combined. ❜
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Amblyopia
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Tor F ❛ most amblyopic vision loss is preventable or reversible with timely detection and appropriate intervention ❜
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T
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❛ Amblyopia is primarily a defect of central vision. The peripheral visual field is usually normal. ❜
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Tor F
T
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❛ also known as contour interaction whereby… o Snellen letters (or equivalent symbols) become more difficult to recognize when closely surrounded by similar forms … such as a full line or field of letters o decrease in resolution or two-point discrimination ❜
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❛ Crowding Phenomenon ❜
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Types of amblyopia
❛ • Strabismic
* Anisometropic
* Sensory Deprivational
• Ametropic Amblyopia ❜
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❛ • Most common form of amblyopia ❜
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❛ STRABISMIC AMBLYOPIA ❜
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❛ • Constant non-alternating heterotropias (usually esodeviations) …or inward deviations
* Thought to result from competitive or inhibitory interaction between neurons carrying the non-fusible inputs from the 2 eyes
* Leading to domination of cortical vision centers by the fixating eye
• Chronically reduced responsiveness to input by the nonfixating eye ❜
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Strabismic amblyopia
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❛ • Second in frequency to strabismic amblyopia
* Develops when unequal refractive errors in 2 eyes causes the image on 1 retina to be chronically defocused
* Results partly from the direct effect of image blur on visual acuity development in the involved eye
• Partly from interocular competition or inhibition … similar to that responsible for strabismic amblyopia. Relative mild degrees of hyperopic or astigmatic anisometropia can induce mild amblyopia. ❜
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❛ ANISOMETROPUC AMBLYOPIA ❜
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❛ less than -3 D difference - usually does not cause amblyopia unilateral high myopia (-6 D or greater) often results in severe amblyopic ❜
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True or false
True
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❛ • Bilateral reduction in visual acuity
• Results from large, approximately equal, uncorrected refractive errors in both eyes
• Mechanism: effect of blurred retinal images alone ❜
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❛ uncorrected high hyperopia ❜
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❛ AMETROPIC AMBYLOPIA ❜
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❛ • Least common but Worst type
• When visual axis is obstructed o Congenital or early acquired cataract Most common cause o Corneal opacities o Vitreous hemorrhage o Ptosis
• Most damaging and difficult to treat ❜
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Sensory deprivational amblyopia
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Common causes of stimulus deprivation in children
. Early onset cataract, aphakia, corneal scar,. drooping eyelid.
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Aphakia means
No lens
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Dense congenital cataracts
Can cause amblyopia on what year?
Less than 6 years old, after 6 years old less harmful Na
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❛ may cause mild to moderate amblyopia or may have no effect on visual development ❜
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❛ small polar cataract and lamellar cataracts- ❜
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❛ is a specific form of deprivation
amblyopia that may be seen after therapeutic patching of the
eye to correct refractive errors ❜
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❛ Occlusion amblyopia- seen after therapeutic patching. ❜
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Best corrected visual acuity in bilateral amblyopia
Vision of less than 20/40 each eye
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Amblyopia grading?
Mild amblyopia = 20/40
moderate amblyopia = 20/40 to 22/80
Severe amblyopia = 20/80 to <20/200
Low vision - better eye is worse than 20/200
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Management dense congenital cataracts
❛ • Eliminate any obstacle to vision Like cataracts
• Correct any significant refractive error
• Force use of the poorer eye by limiting use of the better eye. ❜
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❛ Through patching The patched eye is the presume better eye, because you are forcing the child to look with the poor eye, so, the poorer eye will develop. That's the principle of patching. However, these children should be closely monitored because it can reverse. Pag nasobrahan, lalakas yung kanan, hihina naman yung eye na pinapatch. It shouldn't be used randomly or unmonitored ❜
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Crossed eyes?
Strabismus
non paralytic = concommitant
paralytic = incommitant
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esotropia vs exotropia
❛ • Eso-deviation = Esotropia = inward deviation o Congenital o Accommodative (refractive, nonrefractive, mixed)
• Exo-deviation = Exotropia = outward deviation o childhood onset o sensory deprivation ❛ convergence insufficiency ❜
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❜
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Causes of paralytic or incommitant
❛ • CN III (Oculomotor) Palsy– all EOMs involved except the LR and the SO muscle
* CN VI (Abducens) Paresis- paralysis of the LR muscle
* CN IV (Trochlear) Paresis– paralysis of the SO muscle
* Neoplastic lesions
• Vascular lesions (HPN, DM, hemorrhage, thrombosis, embolism, aneurysm) ❜
— Page 12 ❛ Causes:
* MR Palsy o Atypical Duane’s retraction syndrome o Uni/Bilateral Internuclear Ophthalmoplegia
* IR Palsy o Myogenic (Myasthenia gravis) o Mechanical limitation (Thyroid Eye Disease) o Trauma (Blowout fracture)
* IO Palsy o Brown Syndrome
• SR Palsy o Trauma (Blowout fracture) o Mechanical limitation (Thyroid Eye Disease) ❜
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True or false ❛ If it's a very young patient, immediately you consider a nonparalytic strabismus. As they age, you consider paralytic causes ❜
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Trie
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❛ Normally, upper lid covers about upper one-sixth of the cornea i.e., about 2 mm.
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In ptosis it covers more than 2 mm. ❜
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Treatment of congenital ptosis
❛ • Treatment of Congenital ptosis- surgical correction.
o In severe ptosis - earliest to prevent stimulus deprivation amblyopia In mild and moderate ptosis - delayed until the age of 3-4 years, when accurate measurements are possible. ❜
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❛ clouding of the lens which leads to a decrease in vision. May be present at birth (congenital) develops later (developmental). ❜
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Cataract
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Causes of cataract
❛ CAUSES
Maternal and infantile malnutrition; Maternal infections by viruses eg. Rubella; Deficient oxygenation owing to placental hemorrhages; Hypocalcemia and storage disorders. ❜
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Assessment of cataract
❛ ASSESSMENT
* Assessment of vision and Ocular status
* Intraocular pressure
* Fundus examination to rule out associated diseases like retinoblastoma
* B scan Ultrasonography – to assess posterior segment of eye
– to rule out retinal detachment
• A scan ultrasonography – to compare axial length of two eyes Assessment of density of cataract. ❜
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Treatment of cataract
❛ TREATMENT
* Not indicated unless vision is impaired Central cataract
* Good vision through clear cortex
* Mydriasis if required
* Monitor distant and near vision
* If opacity is large and dense – cataract surgery
* Intraocular lens may be implanted after surgery
• Lamellar cataract – surgery not advisable until child is 1-2 years old ❜
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Manifestations of bacterial conjunctivitis
❛ Bacterial conjunctivitis: Purulent discharge, Crusting of eye lids, Inflamed conjunctiva, Swollen lids ❜
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Man if of viral conjunctivitis
❛ Occurs with URI, Serous (watery discharge), Inflamed conjunctiva, Swollen lids ❜
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Manifestation of allergic conjunctivitis
❛ Itching, Watery to thick, stringy discharge, Inflamed conjunctiva, Swollen lids ❜
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Conjunctivitis caused by foreign body
❛ Tearing, Pain, Inflamed conjunctiva, usually only one eye is affected ❜
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Chemical conjunctivitis
❛ Mild eyelid edema, Sterile, nonpurulent eye discharge ❜
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Mx of conjunctivitis
❛ MANAGEMENT
Treat the cause
* Viral conjunctivitis: self-limiting, remove secretions.
* Bacterial conjunctivitis: topical antibacterial agents (eg.
Polysporin, sodium sulfacetamide, trimethoprim and polymyxin, Fluroquinolones)
• Eye drops in daytime, ointment at bedtime ❜
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❛ • red, sore lump at the edge of the eyelid, caused by bacteria.
• Warm compress + antibiotic, sometimes I&C (incision and curettage) ❜
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stye
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❛ • swollen lump on the eyelid, caused by a clogged oil gland.
• Warm compress, sometimes I&C ❜
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❛ CHALAZION ❜
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❛ • Very common. Determined by:
o Refractive power of cornea and lens o Length of the Eye (1mm change represents about 3 diopters change in refraction) o Refractive errors of up to 5 diopters are considered to be biological variation ❜
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Refractive errors
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Free or false ❛ Higher degrees of refractive errors are associated with structural anomalies of the ocular structures eg. Cornea, lens, choroid, retina ❜
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Trie
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Emmetropia vs ametropia
❛ • Normal vision - no refractive error or emmetropia
• Parallel rays of light focus on the fovea
• when parallel rays of light are not focused on the fovea is ametropia. ❜
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Ametropia can be axial, curvature, index, what is the diff?
❛ Axial– 1 mm change represents about 3 diopters change in refraction o Curvature– 1 mm change in radius of curvature of cornea represents about 6 diopters of change in refraction o Index– due to change in the refractive index of the refractive media ❜
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What type of myopia ❛ o Usual onset by adolescence but may begin as late as 25 years of age o Gradually increases until the eye is fully grown o Seldom exceeds -6.00 diopters ❜
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Simple myopia
99
What type of myopia? ❛ Commonly, this begins as a physiological but rather than
stabilizing when adult size of the eyeball is achieved…
o eye continues to enlarge It is associated with physiological changes in the posterior
segment in the that can be seen on ophthalmoscopy o can lead to complications like retinal breaks and retinal
detachment o Over -6.00 D, can go up to > minus 20 diopters ❜
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❛ Pathologic Myopia ❜
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❛ Parallel rays brought to a focus BEHIND the retina. The eye is weaker for the axial length of the eye This is contrast with the previous condition called myopia, wherein the focus is in front of the eye. Here, the focus of the parallel rays falls behind the retina ❜
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❛ HYPEROPIA/HYPERMETOPIA ❜
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Latent vs manifest hyperopia
❛ Latent – corrected by normal physiologic tone of the ciliary muscle
• Manifest – the remaining portion not corrected by normal physiologic tone ❜
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❛ • The eye has different refractive power in different meridians of the eye.
• Vertical rays being focused in one position (in front, behind or on the fovea) and horizontal rays focused on another. ❜
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Astigmatism
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Regular is irregular astigmatism
❛ When the two meridians are at right angle to each other it is called regular astigmatism. Otherwise, it is an irregular astigmatism ❜
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Classifications of astigmatism
❛ Classified as:
o Simple – one axis ametropic either myopic/hyperopic Ametropic meaning on the retina and the other axis falls either in front or behind o Compound – both axis ametropic but either myopic or hypermetropic o Mixed – each axis of opposite power ❜
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In adults all refractive errors present as
❛ • Asthenopia - eye strain and visual fatigue
* Blurring of vision
* Ocular discomfort
* Increased sensitivity to light
• Headache – commonly presenting after visual work esp those above 40 yo ❜
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In children, refractive errors can present as
❛ Can present in a variety of ways
* In preverbal children it can present as delayed milestones of visual development, inability to focus at visually stimulating objects, follow light or bright objects.
* Squint Or misalignment
• Lazy eye or eyes ❜
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In school children refractive errors will manifest as
❛ Lack of interest in visual tasks, class work
* General apathy
* Withdrawn behavior
* Difficulty in reading or seeing the black/white board from a distance
* Squint
• Lazy eye ❜
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Physical exam signs of refractive errors
❛ Decreased visual acuity that improves with pinhole
* The eyeball may be obviously small (hyperopic) or large (myopic)
* The cornea may be conical in shape causing irregular astigmatism (keratoconus)
• Posterior segment may show abnormalities (myopia) ❜
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