Retinal Vascular Disease Flashcards
Hypoperfusion Syndrome was formerly known as
Venous Stasis Retinopathy
Note: this is a misnomer because the defect is in arteries not veins
Hypoperfusion Syndrome is caused by
A blockage in the carotid or ophthalmic artery
Hypoperfusion Syndrome is an early and often asymptomatic stage of
Chronic Ocular Ischemia Syndrome
With Hypoperfusion Syndrome, a patient may complain of
Dull, chronic ache (on ipsilateral side of blockage) + possible transient vision loss (amaurosis fugax)
Why might a bruit and decreased pulse be experienced in Hypoperfusion Syndrome?
Bruit — whooshing sound at site of obstruction
Blockage —> turbulent blood flow —> bruit
Pulse will be decreased downstream from obstruction
Bruits can be identified when blockage is at ___%
30-85%
What is the correct orientation of a stethoscope to identify a bruit?
Using the BELL
For definitive diagnosis of Hypoperfusion Syndrome, what test is required?
Carotid imaging
What clinical findings would you expect to see during a fundus exam in a patient with Hypoperfusion Syndrome?
- Peripheral/mid-peripheral dot blot hemes
- Dilated veins
Defects spare the posterior pole
Ocular Ischemic Syndrome is often misdiagnosed as…
Vein occlusion or Diabetic Retinopathy
What is the visual impact of a patient with Ocular Ischemic Syndrome?
50% of OIS pts Count Fingers within 1 year
Ocular Ischemic Syndrome is typically ____ (unilateral/bilateral)
Unilateral
What clinical findings might you see in Ocular Ischemic Syndrome? (7)
- NVD/NVI/NVE
- Conj congestion
- Sluggish pupils
- Iritis
5.Corneal edema - Cotton wool spots
- Elevated inflamm markers (CRP, homocysteine)
What testing is used to diagnose Ocular Ischemic Syndrome?
Carotid Doppler Ultrasound
What is the treatment for Ocular Ischemic Syndrome?
- Systemic management
- Anti-VEGF
- Treat ocular findings (e.g. Mac edema, iritis, etc)
- Surgery (endarterectomy, carotid artery sheathing)
Describe the Carotid Doppler Ultrasound and how to read the results.
- Non-invasive
- B-mode and Doppler ultrasound used
- Best detects occlusions in vessels
- PSV (Peak Systolic Velocity) and EDV (End Diastolic Velocity) is used to determine blockage
if PSV > 125, there is at least a 50% blockage
What would you expect to see on IVFA in a patient with. Ocular Ischemic Syndrome?
Delayed retinal AV time and possibly macular edema in late phase
In conjunction with the primary diagnostic test, what other tests are performed to diagnose Ocular Ischemic Syndrome?
- Magnetic Resonance Angiography (MRA)
- Computerized Tomographic Angiography (CTA)
- IVFA
- ESR, CRP, CBC, + Cardio Work-up
CT is more accessible, but MRA gives better view of tissue
What values are most important when reading a Carotid Doppler?
PSV (Peak Systolic Volume) and EDV (End Diastolic Velocity)
Carotid Doppler: PSV of above 125 indicates
At least 50% blockage
What is the most common inherited blood disorder in the USA?
Sickle Cell Retinopathy
What is a hemoglobinopathy?
A genetic disorder with structurally abnormal hemoglobin
T/F: Both sickle cell patients and sickle cell trait carriers exhibit resistance to malaria
TRUE
HbA
Normal
HbS
Sickle cell allele
HbC
Benign Hemoglobinopathy
HbThal
Decreased Hb production
Which sickle cell alleles exhibit the worst systemic complications?
SS
What sickle cell alleles exhibit most severe ocular complication?
SC and SThal
What are some factors that exacerbate sickling of cells?
- Acidosis
- Hyperosmolarity
- Cold weather
- Dehydration
What are the lab tests that can detect Sickle Cell?
- Solubility Test (SickleDex)
- Sickle Prep Test (Metabisulfite Slide Test)
- Hemoglobin Electrophoresis the only one that can determine genotype
5 Stages of Sickle Cell Retinopathy
- Peripheral Arterial Occlusion
- Peripheral AV Anastomoses
- Pre-retinal sea-fan neo
- Vitreous hemorrhage
- TRD
Non-proliferative signs of SCR
- Comma sign (conj)
- Ant Seg ischemia
- Silvering of arterioles
- ERM
- Retinoschisis
- Salmon patch hemes
- Sunburst pigment
- Refractile bodies
- Angioid Streaks
- Artery occlusion
- Peripheral anastomoses
- Hyphema
Why do sickle cell patients have elevated IOP?
HbS polymerization in aqueous humor —> sickling of RBC —> TM blockage —> elevated IOP
How do you treat hyphema?
- Cyclo
- Steroids
- Keep head tilted up
What IOP lowering drop should be avoided in sickle patients and why?
CAIs; promotes sickling
Osmotic agents (can be used sparingly); increases blood viscosity
SCR: 24-24 Rule w/ Hyphema
If IOP ≥ 24 mmHg over any 24 hr period, surgical intervention w/ ant seg washout (Parasynthesis)
What is the Tx for Stage 1 Proliferative SCR?
Educate and monitor
What is the Tx for Stage 2 Proliferative SCR?
Educate and monitor
What is the Tx for Stage 3 Proliferative SCR?
Peripheral scatter photocoagulation/cryotherapy around sea fan
What is the Tx for Stage 4/5 Proliferative SCR?
Vitreoretinal surgery + Anti-VEGF
What are some complications associated with Vitreoretinal Surgery in SCR pts?
Systemic: pulmonary, cerebral, and thromboembolic complications + Ocular: ant seg ischemia and hemorrhage w/ 2º GLC
What is the benefit to PSP/Cryotherpathy in SCR pts?
regression of neo fronds and decrease risk of VH
T/F: VH is immediate indication for Vitreoretinal Surgery
FALSE; most of time time, VH settles w/ gravity & reabsorbs*
unless it affects vision
Compare size of cells exhibited in uveitis vs retinal vasculitis.
Cells larger in retinal vasculitis
Phlebitis
Inflammation of retinal veins
Arteritis
Inflammation of retinal arteries
Causes of retinal vasculitis
Either caused by primary ocular disease or as a specific presentation of systemic vasculitis
Eales Disease
Idiopathic peripheral retinal phlebitis
Typical Eales Disease pt
Young, healthy male from India, Pakistan, Afghanistan
Hallmark of Eales
Frequent, recurrent VH
inflammation —> occlusion —> non-perfusion —> Neo —> VH
Treatment for Eales
PRP (+ maybe Anti-VEGF)
Susan Syndrome Triad
- Multiple BRAO
- Hearing Loss
- Encephalopathy
Snowball lesions in corpus callosum is indicative for which disorder?
Susan Syndrome (Encephalopathy)
leads to stroke
Typical Susan Syndrome Pt
Woman 30’s
TX for Susan Syndrome
Corticosteroids + Immunosuppressants
IRVAN stands for
Idiopathic Retinal Vasculitis, Aneurysms, and Neuroretinitis
Stages of IRVAN
- Vasculitis, MA, Neuroretinitis, Exudation
- Angiographic evidence of capillary non-perfusion
- Post Seg NVD/NVE and/or VH
- Ant Seg Neo
- Neo GLC
What stage of IRVAN warrants treatment?
Stage 2 (Capillary non-perfusion)
TX: PRP
