35 terms

Optho - Disorders of the Retina

Retina Lecture from 9/3/2013

Terms in this set (...)

Causes of Retinal damage?
-Premature birth
-diabetes mellitus
-Arterial Hypertension (HPTN)
-Sickle Cell disease
Describe Retinopathy of prematurity (ROP)
-Abnormal vessel growth in retina
-retina can detach
-seen in premies born >31weeks
-most common vision loss in children
*Prognosis: Not all babies respond to treatment, Retinal detachment may develop. Surgery to reattach the retina
Statistics of prevalence of Retinopathy of prematurity (ROP)
-half of all premies in the US develop ROP (about 15,000 infants)
-90% of infants with ROP have a mild stage and do not require treatment
-Infants with severe stages need treatment to prevent impaired vision
-About 500 infants each year in the US become legally blind from ROP
Treatment for advanced Retinopathy of prematurity (ROP)
'Mild cases will often improve without treatment'
Advanced disease:
-Laser therapy:Burns away the periphery of the retina that contains the abnormal vessels
-Cryotherapy: Destroys spots on the peripheral areas of the retina
(Both treatments are invasive surgeries, and destroy some side (peripheral) vision, but save the sharp, central vision
Treatment of Severe Retinopathy of prematurity (ROP)
*Scleral buckle: silicone band is placed around the eye and tightened to keep the scar tissue from being pulled. Band must be removed as the eye grows
*Vitrectomy : (Stage V only)
-Removing the vitreous and replacing it with saline solution
-Then scar tissue is cut out of the retina to allow the retina to lay back down
Diabetic Retinopathy
-Present in about 40% of diagnosed diabetic patients
-*Leading cause of new blindness among adults 20-65 years old*
-Increased prevalence and severity with longer duration and poorer control of diabetes
-Type 1 patients: not detectable for at least 3 years after diagnosis
-Type 2 patients: present in 20% of patients at diagnosis
How many kinds of Diabetic reinopathy?
- Non-proliferative retinopathy
-Proliferative retinopathy
Non-proliferative retinopathy clinical findings
-Dilation of veins
-Retinal hemorrhage
-Retinal edema
-Hard exudates
Background retinopathy
-Mild abnormalities
-No impairment of visual acuity
-Edema, exudates, or ischemia involving the macula
Proliferative retinopathy clinical findings
-Vitreous hemorrhage (slide included after retinopathy)
-Retinal detachment- pulled by new vessels
-Without treatment, worse prognosis than non-proliferative
Who should be screened for diabetic retinopathy?
Adolescent and adult patients with diabetes should have annual screening
**Dilated exam
*Clinical findings can be difficult to see without a dilated exam
Treatment of Diabetic retinopathy
-Medical management of diabetes to optimize: Blood glucose, Blood pressure, Renal function, Serum lipids
-Laser photocoagulation to treat proliferative retinopathy
-Vitrectomy to remove persistent vitreous hemorrhage
-Ophthalmology referral for all; *Urgent
**Emergently for sudden loss of vision
What is Hypertensive retinopathy?
Retinopathy caused by hypertnsion that has damaged the vessels in the retina. Classifications; Mild, Moderate, and severe
Describe Mild Hypertensive retinopathy:
-Retinal arteriolar narrowing- abnormal light reflexes develop: ***Silver and copper wiring: Arteriosclerosis with moderate vascular wall changes (copper wiring) to more severe vascular wall hyperplasia and thickening (silver wiring)
-Arteriolar wall thickening (loss of transparency leading to *Arteriovenous nicking
What is Arteriovenous nicking?
When arterial walls lose their transparency, changes appear in the AV crossing
AV nicking: the vein appears to stop abruptly on either side of the artery
Describe moderate hypertensive retinopathy
In addittion to the damage in mild, you will also have:
Hemorrhages (Flame and Dot shaped), Cotton-wool spots, Hard exudates, and
Severe HPTN retinopathy
All of the same from mild to moderate, plus optic disc edema, aka papilledema- Optic disc swelling,
Result of increased intracranial pressure, and is Typically bilateral
Treatment of HPTN retinopathy
-Control blood pressure
-Urgent ophthalmologist referral
-If papilledema is present, must rapidly lower the blood pressure (ED or inpatient)
Effect of sickle cell disease on proliferative retinopathy
-Vaso-occlusion may begin in childhood
-Proliferative retinopathy can lead to vitreous hemorrhage and retinal detachment
-Part of the progression of sickle cell disease
-**Not like hypertension or diabetes where one can get better "control" over the disease**
-Retinal laser photocoagulation reduces the frequency of vitreous hemorrhage from new vessels
Number one treatment for all retinopathies?
Retinal laser photocoagulation
Retinopathy in HIV
-Clinical manifestations: Cotton-wool spots, retinal hemorrhages, microaneurysms
-CMV (cytomegalovirus) retinitis
Occurs when **CD4 counts are below 50
Clinical manifestations: Blurring or loss of central vision, Blind spots, Floaters, Flashing lights
Severe HIV retinopathy and full thickness retinal necrosis:
-Scar tissue forms and it can tear, and leads to retinal detachment
**Ophthalmologist referral
Treatment: based on severity: Antiviral medication- ID consult, Range from oral, to IV, to intravitreal injections (in the eye!)
Symptoms and clinical findings of Vitreous hemorrhage:
-Sudden vision loss
-Abrupt onset of floaters
-Externally, eye looks fine
-Upon examination of the fundus, the lens is clear, but you are unable to see fundal details clearly
Causes of Vitreous hemorrhage(think differential diagnosis ddx)
-Diabetic retinopathy
-Retinal tears
-Retinal detachment
-Retinal vein occlusion
-Blood dyscrasias (i.e. bleeding disorders)
-Subarachnoid hemorrhage
-Emergent ophthalmologist referral
-Treat underlying cause
Retinal vascular occlusion
-Caused by blood clots or atherosclerosis
*Central and branch retinal vein occlusion
*Central and branch retinal artery occlusion
Symptoms and clinical findings of Central and branch retinal vein occlusion:
-NO Sudden monocular loss of vision
pain, NO redness
Ophthalmoscope exam findings:
-Widespread retinal hemorrhages
-Retinal venous dilation
-Tortuous veins
-Cotton-wool spots
-Optic disc swelling
Treatment and prognosis of Central and branch retinal vein occlusion:
*Emergent ophthalmologist referral
-Laser photocoagulation
-Intravitreal injection of steroid
-Screen for diabetes, hypertension, hyperlipidemia, glaucoma and lupus
-Severity of visual loss is a good predictor of visual outcome
-Poorer prognosis for pts with neovascular glaucoma
Possible complications from Central and branch retinal vein occlusion
-Widespread retinal ischemia
-Poor visual acuity (20/200 or worse)
-Risk of developing glaucoma
Symptoms and Clinical Findings of Central retinal artery occlusion
-Sudden *monocular loss of vision
-NO pain and NO redness
Swollen retina
-*Cherry-red spot on the fovea (board question)*(test ?)
-Retinal arteries are thin appearing
-Pale optic disc
Management of Central retinal artery occlusion
Emergent referral to ophthalmologist!
-Evaluate for heart murmurs
-EKG for arrhythmias
-Ultrasound of the carotid arteries
-May need echocardiograph, CT or MRI to evaluate carotid arteries
-Screen for diabetes, hyperlipidemia and lupus
--Pts 50 years old and older, must consider giant cell/temporal arteritis (inflammation of the lining of the arteries, typically of the temporal region)
Initial management (within a few hours of onset) of Central retinal artery occlusion
1.Have pt lie flat
2.Ocular massage
3.High concentrations of inhaled oxygen
4. IV acetazolamide
5. Anterior chamber paracentesis
6. High dose corticosteroids if giant cell arteritis is suspected
Board question: "Curtain spreading across the field of vision" with Sudden onset of visual loss in one eye, NO pain, and NO redness?
Retinal detachment
Causes of Retinal detachment
-Tear in the retina
-Changes in the vitreous
-Cataract extraction
-Penetrating trauma
-Blunt trauma
-Tractional detachment
-Preretinal fibrosis (i.e. secondary to proliferative retinopathy)
Traumatic retinal detachment
Ocular injury
In babies and kids, think abuse (shaken baby syndrome)
Symptoms and clinical findings of retinal detachments:
-Detachment typically starts in the superior temporal area
-Spreads rapidly
-Patient c/o visual field loss that starts inferiorly and expands upwards
-Retina is seen hanging in the vitreous like a gray cloud
Treatment of retinal detachment and prognosis
**Refer to ophthalmologist emergently
-Surgically repair the retinal tears via laser photocoagulation or vitrectomy (bubble of gas holds the retina in place- gradually absorbed)

-80% cured with one operation
-15% require multiple surgeries
Remaining never attach