Retinal detachment

Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue.^[1] Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is a surgical emergency.^[2]

Retinal detachment

Ophthalmology

The retina is a thin layer of light-sensitive tissue on the back wall of the eye. The optical system of the eye focuses light on the retina much like light is focused on the film in a camera. The retina translates that focused image into neural impulses and sends them to the brain via the optic nerve. Occasionally, posterior vitreous detachment, injury or trauma to the eye or head may cause a small tear in the retina. The tear allows vitreous fluid to seep through it under the retina, and peel it away like a bubble in wallpaper.

Diagnosis[edit]

Symptoms[edit]

As the retina is responsible for vision, persons experiencing a retinal detachment have vision loss. This can be painful or painless. Symptoms of retinal detachment may include:^[1]

Rhegmatogenous retinal detachment – A rhegmatogenous retinal detachment occurs due to a hole or tear (both of which are referred to as retinal breaks) in the retina that allows fluid to pass from the vitreous space into the subretinal space between the sensory retina and the . This is the most common form of retinal detachment, affecting approximately 1 in 10,000 individuals per year.^[4]

retinal pigment epithelium

Exudative, serous, or secondary retinal detachment – An exudative retinal detachment occurs due to inflammation, injury or vascular abnormalities that results in fluid accumulating underneath the retina without the presence of a hole, tear, or break.

Tractional retinal detachment – A tractional retinal detachment occurs when fibrovascular tissue, caused by an injury, inflammation or neovascularization, pulls the sensory retina from the retinal pigment epithelium.

Combined traction-rhegmatogenous

There are 4 main types of retinal detachment:^[3]

A small number of retinal detachments result from trauma, including blunt blows to the orbit, penetrating trauma, and concussions to the head. A retrospective Indian study of more than 500 cases of rhegmatogenous detachments found that 11% were due to trauma, and that gradual onset was the norm, with over 50% presenting more than one month after the inciting injury.^[5]

Retinal detachment is more common in those with severe (above 5–6 diopters), as their eyes are longer, their retina is thinner, and they more frequently have lattice degeneration. The lifetime risk increases to 1 in 20.^[9] Myopia is associated with 67% of retinal detachment cases. Patients with a detachment related to myopia tend to be younger than non-myopic detachment patients.

myopia

Retinal detachment can occur more frequently after surgery for . The estimated of risk of retinal detachment after cataract surgery is 5 to 16 per 1000 cataract operations.^[10] The risk may be much higher in those who are highly myopic, with a frequency of 7% reported in one study.^[11] Young age at cataract removal further increased risk in this study. Long term risk of retinal detachment after extracapsular and phacoemulsification cataract surgery at 2, 5, and 10 years was estimated in one study to be 0.36%, 0.77%, and 1.29%, respectively.^[12]

cataracts

Tractional retinal detachments can also occur in patients with proliferative ^[13] or those with proliferative retinopathy of sickle cell disease.^[14] In proliferative retinopathy, abnormal blood vessels (neovascularization) grow within the retina and extend into the vitreous. In advanced disease, the vessels can pull the retina away from the back wall of the eye causing a traction retinal detachment.

diabetic retinopathy

The risk of retinal detachment in otherwise normal eyes is around 5 in 100,000 per year.^[6] Detachment is more frequent in the middle-aged or elderly population with rates of around 20 in 100,000 per year.^[7] The lifetime risk in normal eyes is about 1 in 300.^[8]

Although retinal detachment usually occurs in one eye, there is a 15% chance of developing it in the other eye, and this risk increases to 25–30% in patients who have had cataracts extracted from both eyes.^[9]

flashes of light () – very brief in the extreme peripheral (outside of center) part of vision

photopsia

a sudden dramatic increase in the number of

floaters

A retinal detachment is commonly but not always preceded by a posterior vitreous detachment which gives rise to these symptoms:

Sometimes a detachment may be due to atrophic retinal holes in which case it may not be preceded by photopsia or floaters.

Although most posterior vitreous detachments do not progress to retinal detachments, those that do produce the following symptoms:

Cryopexy and laser photocoagulation

Prevention[edit]

Retinal detachment can sometimes be prevented. The most effective means is by educating people to seek ophthalmic medical attention if they have symptoms suggestive of a posterior vitreous detachment.^[15] Early examination allows detection of retinal tears which can be treated with laser or cryotherapy. This reduces the risk of retinal detachment in those who have tears from around 1:3 to 1:20.

There are some known risk factors for retinal detachment. There are also many activities which at one time or another have been forbidden to those at risk of retinal detachment, with varying degrees of evidence supporting the restrictions.

Cataract surgery is a major cause, and can result in detachment even a long time after the operation. The risk is increased if there are complications during cataract surgery, but remains even in apparently uncomplicated surgery. The increasing rates of cataract surgery, and decreasing age at cataract surgery, inevitably lead to an increased incidence of retinal detachment.

Trauma is a less frequent cause. Activities which can cause direct trauma to the eye (boxing, kickboxing, karate, etc.) may cause a particular type of retinal tear called a retinal dialysis. This type of tear can be detected and treated before it develops into a retinal detachment. For this reason governing bodies in some of these sports require regular eye examination.

Individuals prone to retinal detachment due to a high level of myopia are encouraged to avoid activities where there is a risk of shock to the head or eyes, although without direct trauma to the eye the evidence base for this may be unconvincing.^[9] Some doctors recommend avoiding activities that suddenly accelerate or decelerate the eye, including bungee jumping and skydiving but with little supporting evidence. Retinal detachment does not occur as a result of eye strain, bending, or heavy lifting.

Retinal detachment