Most common presenting symptoms: Flashing lights or new floaters

Introduction

A retinal tear is described as a full thickness defect in the retina, normally in the periphery of the retina.

Retinal tears are a common presentation in the ophthalmology department and require urgent diagnosis to prevent the development of a retinal detachment and potentially complete visual loss. It is important for all doctors to recognise the symptoms that a patient with a retinal tear may present with.

This article is designed to help SHO doctors manage a patient that presents with the symptoms of a retinal tear/ detachment and should serve only as an introduction to this topic.

Pathophysiology

Most retinal tears develop due to traction at sites of vitreoretinal adhesion, occurring in up to 1 in 5 eyes with a posterior vitreous detachment (PVD). When a tear occurs, this allows vitreous to seep into this break, potentially separating the neurosensory retina from the retinal pigment epithelium (RPE), leading to a retinal detachment.

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Symptoms:

Flashing lights (photopsia) – caused by physical stimulation of the retina from vitreoretinal traction.

Floaters (myodesopsia) – mobile vitreous opacities. Often described as spots, cobwebs or flies and exist as vitreous opacities such as blood, glial cells or aggregated collagen fibres.

Often these symptoms come on suddenly but may have been present/ worsen over a few days.

NB. Beware of the patient that describes a shadow in their vision (often described as a curtain)/ significant reduction in visual acuity – these patients should be urgently assessed for a retinal detachment.

Differentials:

• Retinal detachment
• Retinal breaks/ tears
• Posterior vitreous detachment
• Retinal dialysis (can often be related to trauma)
• Vitreous haemorrhage
• Macular oedema

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Risk factors

• Advanced age 
• Myopia (short sightedness)
• Trauma to the eye   
• Family history of retinal tears or detachment 
• Prior eye surgery  
• Lattice degeneration

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Basic examination tests that can be performed in the A&E department:

• Visual acuity using a Snellen chart
• Pupil check for Relative Afferent Pupillary Defect (RAPD) – this will often be normal
• Visual fields to confrontation – if the patient is describing a shadow in their vision this will be confirmed with this test

Findings on examination:

• Shafer’s sign “tobacco dust” – these are pigment cells that come from the RPE of the retina. These are indicative of a retinal break (provided the patient hasn’t undergone recent ophthalmic surgery) (Figure 1)
• Red cells in the anterior vitreous (evidence of vitreous haemorrhage) – these indicate a retinal break or proliferative process i.e a vitreous haemorrhage in a patient with diabetes would act as a common example

Figure 1: Left, copious tobacco dust. Right, smaller area hence harder to spot dust (3)

Ophthalmological tests performed within the department will include:

• Assessment using lenses to visualise all edges of the retina +/- indentation and contact lens assessment.
• Retinal imaging including Optos and Optical Coherence Tomography (OCT), primarily of the macula to ensure this is not affected.
• If there is a poor view to the retina (i.e due to haemorrhage/ dense cataract), then a B scan (ultrasound of the eye) will be performed for better visualisation of the retina.

Management:

Retinal tears should normally be treated urgently to prevent progression to a retinal detachment.

The mainstay of treatment is to perform a laser retinopexy.

This involves placing the patient on a machine similar to the slit lamp and using a contact lens to fire a barrage of laser around the retinal break. This will help prevent progression to a retinal detachment and is generally a safe procedure.

Follow up in the surgical retina clinic will be advised after this procedure is performed and all patients should be adequately safety netted and advised of the risk of this progressing to a retinal detachment.

Other options include:

Cryotherapy=indicated in very peripheral lesion.  

Observation if a patient is unable to tolerate having a retinopexy.

Not all tears will require treatment such as low risk breaks/tears in patients with no symptoms. These tears/breaks will be followed up to ensure they remain stable and don’t progress further. If they progress, then treatment will be offered.

Retinal detachments will require urgent surgery to prevent progression/ involvement of the macula and to preserve central vision. Patients will be advised to posture in a particular position pre-operatively to reduce the risk further progression.

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Horseshoe tear before and after laser retinopexy:

(4) (5)

Some additional reading if of further interest:

Types of retinal tears:

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References:

1.        John F. Salmon. Retinal Breaks. In: Kanski’s Clinical Opthalmology: A systematic approach . Ninth Edition. Elsevier Limited ; 2020. p. 666–8.

2.        Vinay A. Shah, Koushik Tripathy, Lawrence S. Geyman, Jason Hsu, Jennifer Lim, Tim Inchul Kim, et al. Lattice Degeneration . 2023.

3.        Macalister G. C53730:PVD and retinal detachment, an optometric approach-management . Mark Allen Group.

4.        Central New York’s Premier Retinal Care Specialist: Retinal tear.

5.        Rafieetary M, Huddleston S. Jobson Medical Information LLC. 2019. A Field Guide to Retinal Holes and Tears.

Written by Dr Lu Jing Tan (FY2), Edited by Dr Matthew Mo (ST1, Ophthalmology) and Dr Purva Patwari (SAS Doctor, Ophthalmology)