EYE-REVISE

Definition​

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• Retinal detachment occurs when the inner layers of the retina, containing nerve fibres and photoreceptors (the neurosensory layer) separate from the underlying, retinal pigment epithelium (RPE) layer

  • the RPE contains cells involved in processing photoreceptors and metabolism

• Allows fluid to track under retina, may lead to retinal detachment

• Ophthalmic emergency - rapid diagnosis and management warranted

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Causes

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• Retinal tear (or 'rhegmatogenous' retinal detachment)

  • the commonest cause of retinal detachment

  • the tear allows fluid to enter and accumulate between the retinal layers

  • most commonly due to posterior vitreous detachment - the vitreous jelly separates from its points of connection on the retina as it degenerates and shrinks with age, pulling on the retina and creating a tear

• Retinal detachment may also occur due to fluid accumulating in between the layers of the retina

  • known as 'exudative' retinal detachment

  • occurs due to an inflammatory process or malignancy​

• Finally, detachment can occur secondary to the formation of abnormal membranes over the surface of the retina, which apply tension to and pull on the retina

  • termed 'tractional' retinal detachment​

  • happens in proliferative retinopathy e.g. diabetic retinopathy

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Risk factors

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• Myopia (short-sightedness)

• Lattice degeneration - abnormal thinning of the retina

• Cataract surgery

• Trauma

• Retinal detachment in the other eye

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Presentation

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• Flashes (photopsias) and floaters in the vision

  • this can happen when posterior vitreous detachment occurs and may precede other symptoms of retinal detachment

• Shadow or curtain coming across the vision

  • may be constant or get progressively worse​

• Visual acuity will be be poor if the macula is involved (responsible for central and fine vision)

  • poor prognosis for vision if macula involvement - likely irreversible visual loss

• The detached retinal layers can be seen on examination of the fundus with a floating, corrugated appearance

  • floating, detached retina may be seen to move with eye movements​​

• Vitreous haemorrhage may be present

• A hole in the retina may be visible with rhegmatogenous detachment

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Management

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• Any patient who develops flashes and floaters should be seen by ophthalmologist within 24 hours of onset of their symptoms

  • detachment that doesn’t involve macula should be operated on within 24 hours of diagnosis

    • warrants urgent intervention as there is a risk of progression to involve the macula and irreversible visual loss​

  • Repair of retinal detachments without involving the macula within the 24h window can result in good visual outcomes

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• Treatment approaches: 

  • scleral buckling​

    • a silicone buckle is applied around the external eye to bring the walls of the eye inwards, pushing the layers of the retina back together​

  • vitrectomy

    • this involved cutting or aspirating the vitreous out of the eye​

    • a bubble of gas or oil is inserted into the space previously occupied by the vitreous; this  pushes the layers of the retina back into place

    • the patient needs to hold their head in a certain position for several days to allow this to work

  • vitreoretinal surgery to break the attachments of abnormal membranes on the retina in tractional retinal detachment

    • a gas bubble may be injected to push the retina back into place afterwards​

• If retinal tear spotted before detachment occurs, can be repaired using: 

  • ​pneumatic retinopexy - intravitreal injection of a gas bubble to flatten the torn retina and bring the edges together​

  • ​laser

  • cryotherapy​

• Repair of retinal tears prior to retinal detachment can achieve good visual outcomes

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References

• James, B., Bron, A. J. and Parulekar, M. V. (2016) Lecture Notes Ophthalmology. 12th edn. Nashville, TN: John Wiley & Sons (Lecture Notes)

• Salmon, J. F. (2019) Kanski’s clinical ophthalmology. 9th edn. London, England: Elsevier Health Sciences.