Retinal Detachment

Question 1

Define retinal detachment

Answer 1

the separation of the inner neurosensory retina from the underlying retinal pigment epithelium, which allows liquified vitreous fluid to accumulate in the subretinal space → progressive loss of vision

Question 2

Aetiology of retinal detachment

Answer 2

Often preceded by retinal tears/breaks that form due to vitreoretinal traction -> small, localised defect in the neurosensory retina
Posterior vitreous detachment may cause one or more retinal tears (vitreous fluid shrinks and separates from the retina as part of normal aging

Question 3

What are the types of retinal detachment

Answer 3

Rhegmatogenous (the commonest form): the vitreous shrinks and partly separates from the retinal surface → retinal tear or break → Continuing traction allows fluid to enter the subretinal space → detachment.

Exudative: leakage of fluid into the subretinal space, often due to inflammatory conditions such as uveitis, or malignant conditions such as choroidal melanoma (treatment resolves detachment)

Tractional: seen in proliferative diabetic retinopathy → abnormal vasculature causes contraction of the vitreous which then pulls on the underlying retina (NO retinal break)

Question 4

Risk factors for retinal detachment

Answer 4

Myopia → posterior vitreous detachment
FHx retinal break or detachment
Previous Hx in affected eye or other eye (1 in 8)
Eye trauma e.g. blunt trauma in boxing
Previous cataract surgery
Proliferative diabetic retinopathy
Inflammatory e.g. uveitis, scleritis
Malignancy e.g. choroidal melanoma, ocular mets

Question 5

Symptoms of retinal detachment

Answer 5

Floaters: mobile dots, lines, haze of varying translucency (blood, pigment cells, inflammatory debris inters the vitreous cavity)
Flashes: perecption of light, recurrent, brief, caused by traction on the retina
Sudden onset painless and progressive visual field loss
- Typically “dark curtain” or “shadow” falling from the periphery to the centre
- Central acuity may be affected if the macula detaches
A reduction in visual acuity, blurred or distorted vision, causing persistent and progressive visual loss.

Question 6

Differentials for retinal detachment

Answer 6

Posterior vitreous detachment
Migraine
Postural hypotension
Optic neuritis
TIA
Choroidal tumour
Drugs e.g. chloroquine

Question 7

Signs of retinal detachment on examination

Answer 7

Ophthal:
- Reduced visual acuity
- Peripheral field loss
- RAPD (extensive detachment)
Fundoscopy:
- Asymmetric red reflex
- Vitreous opacities
- Detached retinal folds (pale, opaque, wrinkle, in larger detachments)

Children: white pupillary reflex (leukocoria) or squint/strabismus

Question 8

Investigations for retinal detachment

Answer 8

Acuity and fundoscopy assesment

Fundoscopy: pale, opaque, wrinkle, in larger detachments

Slit lamp examination: RD; retinal break; vitreoretinal pathology (traction or presence of pigment)

Indirect ophthalmoscopy: RD; retinal break; vitreoretinal pathology (traction or presence of pigment)

B-scan US: when media opacity prevents visualisation of fields

Question 9

Management for retinal detachment

Answer 9

Urgent referral to ophthal

Laser therapy (Creates a scar adhesion between the retina and retinal pigment epithelium, sealing the hole and preventing fluid access into the subretinal space)
Cryotherapy (Creates a scar adhesion between the retina and retinal pigment epithelium, sealing the hole and preventing fluid access into the subretinal space)

Surgery
- Vitrectomy — relieves traction by removing the vitreous attached to the retinal breaks. A gas or oil bubble is then used to span and close the retinal break until a scar develops.
- Scleral buckling — a silicone ‘buckle’ is placed on the scleral surface over the retinal breaks; this indents the eye wall to make contact with the detached retina. The aim is to close off retinal breaks and reduce vitreal traction.
- Pneumatic retinopexy — a small expansile gas bubble is injected into the vitreous cavity. This expands over 1–3 days, and by instructing the person to ‘posture’ in a specific position (for example, on one side or face down) as much as possible for several days after surgery, the bubble can be positioned to close the retinal break, allowing the retinal pigment epithelium pump to reattach the retina.

Question 10

Prognosis for retinal detachment

Answer 10

Retinal detachment is a preventable cause of permanent vision loss, as prompt recognition and management may allow early surgical repair before the macula is detached
Treatment may be over 95% effective in preventing progression to full retinal detachment.
Children tend to have a poorer prognosis in visual outcomes compared with adults. This is due to the increased risk of late detection as children are less likely to report reduced vision or visual disturbance, and different underlying disease processes
If left untreated, symptomatic retinal detachment invariably results in permanent loss of vision