DIS - Vitreous Retinal Traction - Week 8 Flashcards
In what four dieases does the vitreoretinal interface play a role in and what technique is extremely useful in evaluating these diseases?
Vitreomacular traction syndrome
Epiretinal membranes
Macular holes
Schisis
-OCT useful for evaluation
What is the pathophysiology of macular oedema (2)?
Due to the breakdown of the blood-retina barrier
Fluid leaks into the retina
List 11 associations or causes of macular oedema.
Diabetic retinopathy
Branch retinal vein occlusion
Retinitis pigmentosa
Chronic uveitis
Intracular surgery
Epiretinal membrane
Choroidal tumours
Perifoveal telangiectasis
Retinal detachment
Idiopathic
Latanoprost
What kind of vision loss tends to occur with macular oedema? What happens to vision after the oedema is absorbed?
Mild VA loss, often 6/12 to 6/19
Vision recovers as oedema absorbed
Can macular oedema cause permanent vision loss?
Chronic oedema can
Is pain involved with vision loss in macular oedema?
No
How does the fovea/macula appear with macular oedema (4)?
Indistinct
Thinkened
Loss of foveal reflex
Exudate
What angiography pattern can be indiciative of macular oedema?
Petallic hyperfluorescence
How does macular oedema appear on an OCT scan (2)?
Retinal thickening and fluid accumulation
What is a differential diagnosis for macular oedema?
Retinoschisis
List four possible outcomes/complications of macular oedema.
None
-spontaneous absorption
Macular hole
Epiretinal membrane
Outer retinal and RPE atrophy
-permanent visiond loss
What is the management of macular oedema (3)?
identify cause
OCT/fluorescein angiography
Treat primary condition
What is the treatment of macular oedema secondary to irvine-gass syndrome or uveitis (3)?
Corticosteroids
NSAIDs
Carbonic anhydrase inhibitors
What is the treatment of macular oedema secondary to diabetes (2)? Comment on the effectiveness.
Anti-VEGF
-good clinicald effectiveness
Steroids
-mixed results, associated with cataract/IOP spike
List two surgical treatment options for macular oedema. List a disease each one is indicated for.
Scatter /grid photocoagulation (diabetic retinoapthy, C/BRVO)
Pars planar vitrectomy (uveitis)
What is an epiretinal membrane and where can it be found? What is it additionally known as (2)?
Avascular, fibrocellular (glial) membranes on the surface of the retina
-cellophane maculopathy
-preretinal fibrosis
Are epiretinal membranes more common in younger or older patients?
Older, >70yoa
List four ocular-related secondary causes of epiretinal membranes.
Posteroir vitreous detachment
Vascular retinopathy
Ocular inflammation
Diabetic retinopathy
List four ocular related iatrogenic causes of epiretinal membranes.
Cataract
Retinal detachment repair
Laser
Cryo
Are there systemic causes of epiretinal membranes? Explain (2).
It is possible
Bilateral in 31% of cases
Unaffected eye of an affected individual has 2.5x greater risk than a single eye of an unaffected individuals
List four symptoms of epiretinal membranes.
Mild blurring and/or metamorphopsia
Micropsia
Macropsia
Monocular diplopia
Is progression fast or slow with epiretinal membranes?
Static/slow progression
What is vision generally like with epiretinal membranes (VA and percentage)?
80% have acuity better than 6/15
Describe grade 0 to 2 for epiretinal membranes.
0 - translucent membrane, no retinal distortion
1 - irregular wrinkling of the inner retinal surface and retinal distortion
2 - opaque, thick membrane, macular pucker
What are the two types of attachments of epiretinal membranes and what percentage are idiopathic/secondary?
Focal or global
50% idiopathic membranes are focal
20% of secondary membrane are focal
What are four things you may see on an OCT scan of an epiretinal membrane?
Presence/absence
Macular thickening
Macular oedema
Traction
List three differential diagnoses for epiretinal membranes.
Retinal detachment
Retinal vacular occlusion disease
Macular oedema
What is a complication of epiretinal membranes?
Vitreomacular traction syndrome
Describe what occurs in vitreomacular traction syndrome. What might this cause? What region is usually hyper-reflective and thickened on OCT?
Vitreous remains attached to the macula and ONH
Focal vitreofoveolar adhesion may cause cystoid macular oedema
Posterior hyaloid is usually hyper-reflective/thickened on OCT
What can be done to improve VA with vitreomacular traction syndrome?
Surgical (or spontaneous) separation of the vitreous from the fovea, which usually improves VA
What is the management of epiretinal membranes (3)?
Exclude other causes
Mild/static cases usually not treated
-25% regresses over 5 years
-refer if symptoms are significant
Is complete recovery of VA following surgery for epiretinal membranes common or rare?
Rare, but usually improves still
What does surgery for epiretinal membranes involve?
Vitrectomy then removal of the membrane
List three intra-operative complications of surgery for epiretinal membranes.
Vitreous haemorrhage
Retinal surface damage
Peripheral retinal breaks
List three post-operative complications of surgery for epiretinal membranes.
Recurrence
Cataract
Retinal detachment
What is thought to be the primary underlying cause for idiopathic macular holes?
Anteroposterior and tangential vitrous traction on the fovea
List 7 causes/associationd of macular holes.
Idiopathic
Myopic degeneration
Vitrous traction/separation/detachment
Trauma
Macular oedema
Epiretinal membrane
Solar retinopathy
Are macular holes typically uni- or bilateral?
Unilateral
List three visual disturbances caused by macular holes. When are these disturbances evident?
Blurred central vision and/or metamorphopsia
Central scotoma (Amsler)
-may only be discovered if the other eye is covered
What does the visual acuity of an eye with a macular hole depend on (2)?
Size and shape (6/7.5 to 6/120)
How do macular holes appear on a fundus exam and what size?
Well-defined round/oval lesion 1/3 DD at the macula with yellow/white deposits in the base
What can be seen suspended over a macular hole?
Semitranslucent tissue called pseudo-operculum
Can OCT easily identify different types of macular holes or are they indistinguishable?
Can easily identify different types
Describe the watzke-allen test for macular holes and what a positive result would be. Ises narrowing or distortion diagnostic?
Using a fundus lens and placing a narrow vertical slit through the fovea
A positive test is when patients detect a break in the bar of light that they perceive
Narrowing or distortion is not diagnostic - interpret with caution
What happens to pathology the smaller the vitreous attachment?
The smaller the vitrous attachment, the greater the force exerted, and the greater the pathology
What does more reflectivity of the prefoveal opacity indicate for surgical closure?
The higher the reflectivity, the lower the chance of surgical closure
What is the management for macular holes ?
Amsler for monitoring the other eye
OCT, distinguish type, check other eye
Fluorescein angiography
Referral for surgery
What two differential diagnoses for macular holes can fluorescein angiography be used to rule out?
Macular oedema
Choroidal neovascularisation
What is the surgical procedure for macular holes (3)? Is it generally successful? What VA outcomes would you expect?
Removal of epiretinal membranes, vitrectomy, following by face-down gas tamponade
>80% success rate
>50% improve VA by 2+ lines
What diameter is considered a large macular hole?
> 400um
Describe the inverted ILM technique and note which type of macular holes this technique is used for and why.
A remnant of the ILM is left attached to the margins of the hole and inverted to cover the macular hole
Prevents post-operative flat-open appearance and improves function VA outcomes
Used for large holes
