[4] Retinal Detachment Flashcards
What is retinal detachment?
A typically progressive condition in which the neuroretina separates (detaches) from the retinal pigment epithelium
What are the types of retinal detachment?
- Rhegmatogenous
- Non-rhegmatogenous
What is the most common type of retinal detachment?
Rhegmatogenous
What are rhegmatogenous retinal detachments preceded by?
Posterior vitreous detachment (PVD)
How can posterior vitreous detachment lead to retinal detachment?
The PVD causes traction on the retina, and potentially a retinal tear. The liquified vitreous can then seep under the retina, causing it to detach
Are rhegmatogenous retinal detachments localised?
They may initially be localised, but without treatment may progress
What might the progression of rhegmatogeous retinal detachments lead to?
Irreversible vision loss
What is a less common type of retinal detachment?
Non-rhegmatogenous retinal detachment
What are the subtypes of non-rhegmatogenous retinal detachment?
- Exudative (serous or secondary)
- Tractionsl
What is exudative non-rhegmatogenous retinal detachment?
When primary damage of the underlying RPE (retinal pigment epithelium) allows subretinal fluid to leak into the subretinal space pushing the retina off
What is tractional non-rhegmatogenous retinal detachment?
When fibres of the vitreous contract and pull the sensory retina away
What is the underlying cause of rhegmatogenous retinal detachment?
Preceded by PVD which is caused by age related degenerative liquefaction and shrinkage of the vitreous
What is the underlying cause of exudative retinal detachment?
Accumulation of serous and/or haemorrhagic fluid in the subretinal space
What can cause accumulation of blood or serous fluid in the subretinal space?
- Hydrostatic factors e.g. severe acute hypertension
- Inflammation e.g. sarcoid uveitis
- Neoplastic effusions
What can cause tractional retinal detachment?
Mechanical forces on the retina usually due to fibrotic tissue
What can cause fibrotic tissue in the vitreous?
- Previous haemorrhage
- Injury
- Surgery
- Infection
- Inflammation
What do risk factors for retinal detachment depend upon?
Type and site of detachment
What are some general risk factors for retinal detachment?
- Myopia (increases risk of PVD)
- Family history
- Previous history of retinal detachment
What are some risk factors of rhegmatogenous retinal detachment?
- Age
- Aphakia
- Previous retinal break
- Marfan’s syndrome
- Lattice degeneration
What is a lattice degeneration?
The peripheral retina becomes thinned or atrophic in a lattice pattern making it prone to damage
What % of the population is lattice degeneration present in?
10%
Why is lattice degeneration important?
It is a cause of retinal detachment in young myopic individuals (usually bilaterally)
What are the risk factors for tractional retinal detachment?
- Proliferative diabetic retinopathy
- Penetrating eye injury
- Retinal vein occlusion
What are the risk factors for exudative retinal detachment?
- Inflammatory disease e.g. uveitis
- Vascular disease e.g. severe hypertension
- Congenital abnormalities e.g. coloboma
How can retinal detachment present?
- New onset floaters
- New onset flashes
- Sudden onset painless, progressive visual field loss
What causes floaters?
Blood or pigment cells entering the vitreous cavity casting shadows on the retina
How can posterior vitreous and retinal detachment floaters be differentiated from lifetime floaters?
They occur more abruptly and dramatically
What are flashes in the vision known as?
Photopsia
What can sudden onset visual field loss in retinal detachment often be described as?
Dark curtain or shadow, usually starts in periphery and progresses towards the centre
Over what time period can visual loss spread in retinal detachment?
Hours to weeks
What are the important parts of an examination in patients with retinal detachment?
- Pupil assessment
- Visual acuity
- Dilated fundus examination
What will a pupil present with in retinal detachment?
RAPD (relative afferent pupillary defect)
What is an RAPD?
The affected pupil appears to dilate when light is shone on it during the swinging light test
Why does the affected pupil appear to dilate in an RAPD?
The pupil constricts more when light is shone in the other eye (due to unaffected afferents) and constricts less (so appears to dilate) when shone in the affected eye (as less light is registered to due to affected afferents)
What does poor visual acuity suggest in suspected retinal detachment?
Involvement of the macula
What can be seen on a dilated fundus examination in retinal detachment?
- Altered red reflex
- Sheet of retina billowing towards centre (in large detachments)
- Potentially visible tear
How may the retina be altered in retinal detachment?
Can have a grey or folded appearance
What investigations can be useful in assessing retinal detachment?
- Slit lamp examination
- USS or OCT
What can USS or OCT be used for in retinal detachment?
To assess type and extent of the detachment as well as associated tears or comorbidities
What are the differentials for retinal detachment based on?
- Conditions causing photopsia
- Conditions causing floaters
What are some conditions that can cause photopsia?
- PVD
- Atypical/ocular migraine
- Optic nerve pathology e.g. optic neuritis
- Stroke/TIA
What are some conditions that can cause floaters?
- PVD
- Vitreous haemorrhage
- Age-related macular degeneration
- Uveitis
- Retinitis pigmentosa
How can the risk of retinal detachment following PVD be reduced?
Prophylactic laser treatment
If a patient has an asymtpomatic retinal hole/tear without detachment, what treatment options are available?
Monitoring or prophylactic laser treatment
How is symptomatic retinal tear/hole treated?
Holes are sealed by cryopexy or laser retinopexy
What is the first line treatment for rhegmatogenous retinal detachment?
Scleral buckle and/or vitrectomy
What is scleral buckling?
A piece of silicone is placed on the scleral surface, secured under the conjuctiva to push the wall of the eye close to the detached retina and helping it to reattach
What is a vitrectomy?
A substance is injected into the vitreous space to help flatten the retina and helps to relieve traction
What is the first line treatment for tractional retinal detachment?
Vitrectomy with or without scleral buckle
How is exudative retinal detachment treated?
Treat underlying cause
What is the main complication of retinal detachment?
Can lead to visual loss if untreated
