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  • Retinal detachment is a disorder of the eye in which the retina peels away from its underlying

  • layer of support tissue. Initial detachment may be localized or broad, but without rapid

  • treatment the entire retina may detach, leading to vision loss and blindness. It is a medical

  • emergency. Permanent damage may occur, if the detachment is not repaired within 24–72

  • hours. 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 or sensor 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.

  • Potential causes or risk factors AIDS

  • Cataract surgery Diabetic retinopathy

  • Eclampsia Family history of retinal detachment

  • Homocysteinuria Malignant hypertension

  • Metastatic cancer, which spreads to the eye Retinoblastoma

  • Severe Myopia Smoking and Passive smoking

  • Stickler syndrome Von Hippel-Lindau disease

  • Types Rhegmatogenous retinal detachment – A rhegmatogenous

  • retinal detachment occurs due to a break in the retina that allows fluid to pass from

  • the vitreous space into the subretinal space between the sensory retina and the retinal

  • pigment epithelium. Retinal breaks are divided into three typesholes, tears and dialyses.

  • Holes form due to retinal atrophy especially within an area of lattice degeneration. Tears

  • are due to vitreoretinal traction. Dialyses are very peripheral and circumferential, and

  • may be either tractional or atrophic. The atrophic form most often occurs as idiopathic

  • dialysis of the young. 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. In evaluation of retinal detachment it is critical to exclude exudative detachment

  • as surgery will make the situation worse, not better. Although rare, exudative detachment

  • can be caused by the growth of a tumor on the layers of tissue beneath the retina, namely

  • the choroid. This cancer is called a choroidal melanoma.

  • Tractional retinal detachment – A tractional retinal detachment occurs when fibrous or

  • fibrovascular tissue, caused by an injury, inflammation or neovascularization, pulls

  • the sensory retina from the retinal pigment epithelium.

  • A minority 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. Signs and symptoms

  • A retinal detachment is commonly preceded by a posterior vitreous detachment which gives

  • rise to these symptoms: flashes of lightvery brief in the extreme

  • peripheral part of vision a sudden dramatic increase in the number of

  • floaters a ring of floaters or hairs just to the temporal

  • side of the central vision a slight feeling of heaviness in the eye

  • Although most posterior vitreous detachments do not progress to retinal detachments, those

  • that do produce the following symptoms: a dense shadow that starts in the peripheral

  • vision and slowly progresses towards the central vision

  • the impression that a veil or curtain was drawn over the field of vision

  • straight lines that suddenly appear curved central visual loss

  • In the event of an appearance of sudden flashes of light or floaters, an eye doctor needs

  • to be consulted immediately. A shower of floaters or any loss of vision, too, is a medical emergency.

  • Risk factors and prevention Risk factors for retinal detachment include

  • severe myopia, retinal tears, trauma, family history, as well as complications from cataract

  • surgery. Retinal detachment can be mitigated in some

  • cases when the warning signs are caught early. The most effective means of prevention and

  • risk reduction is through education of the initial signs, and encouragement for people

  • to seek ophthalmic medical attention if they suffer from symptoms suggestive of a posterior

  • vitreous detachment. 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. For this reason, the governing bodies in some sports require

  • regular eye examination. Trauma-related cases of retinal detachment

  • can occur in high-impact sports or in high speed sports. Although some doctors recommend

  • avoiding activities that increase pressure in the eye, including diving and skydiving,

  • there is little evidence to support this recommendation, especially in the general population. Nevertheless,

  • ophthalmologists generally advise patients with high degrees of myopia to try to avoid

  • exposure to activities that have the potential for trauma, increase pressure on or within

  • the eye itself, or include rapid acceleration and deceleration, such as bungee jumping or

  • roller coaster rides. Intraocular pressure spikes occur during any

  • activity accompanied by the Valsalva maneuver, including weightlifting. An epidemiological

  • study suggests that heavy manual lifting at work may be associated with increased risk

  • of rhegmatogenous retinal detachment. In this study, obesity also appeared to increase the

  • risk of retinal detachment. Genetic factors promoting local inflammation

  • and photoreceptor degeneration may also be involved in the development of the disease.

  • Diagnosis Retinal detachment can be examined by fundus

  • photography or ophthalmoscopy. Fundus photography generally needs a considerably larger instrument

  • than the ophthalmoscope, but has the advantage of availing the image to be examined by a

  • specialist at another location and/or time, as well as providing photo documentation for

  • future reference. Modern fundus photographs generally recreate considerably larger areas

  • of the fundus than what can be seen at any one time with handheld ophthalmoscopes.

  • Treatment There are several methods of treating a detached

  • retina, each of which depends on finding and closing the breaks that have formed in the

  • retina. All three of the procedures follow the same three general principles:

  • Find all retinal breaks Seal all retinal breaks

  • Relieve present vitreoretinal traction Cryopexy and laser photocoagulation 

  • Cryotherapy or laser photocoagulation are occasionally used alone to wall off a small

  • area of retinal detachment so that the detachment does not spread.

  • Scleral buckle surgery  Scleral buckle surgery is an established treatment

  • in which the eye surgeon sews one or more silicone bands to the sclera. The bands push

  • the wall of the eye inward against the retinal hole, closing the break or reducing fluid

  • flow through it and reducing the effect of vitreous traction thereby allowing the retina

  • to re-attach. Cryotherapy is applied around retinal breaks prior to placing the buckle.

  • Often subretinal fluid is drained as part of the buckling procedure. The buckle remains

  • in situ. The most common side effect of a scleral operation is myopic shift. That is,

  • the operated eye will be more short sighted after the operation. Radial scleral buckle

  • is indicated for U-shaped tears or Fishmouth tears, and posterior breaks. Circumferential

  • scleral buckle is indicated for multiple breaks, anterior breaks and wide breaks. Encircling

  • buckles are indicated for breaks covering more than 2 quadrants of retinal area, lattice

  • degeneration located on more than 2 quadrant of retinal area, undetectable breaks, and

  • proliferative vitreous retinopathy. Pneumatic retinopexy 

  • This operation is generally performed in the doctor's office under local anesthesia. It

  • is another method of repairing a retinal detachment in which a gas bubble is injected into the

  • eye after which laser or freezing treatment is applied to the retinal hole. The patient's

  • head is then positioned so that the bubble rests against the retinal hole. Patients may

  • have to keep their heads tilted for several days to keep the gas bubble in contact with

  • the retinal hole. The surface tension of the gas/water interface seals the hole in the

  • retina, and allows the retinal pigment epithelium to pump the subretinal space dry and "suck

  • the retina back into place". This strict positioning requirement makes the treatment of the retinal

  • holes and detachments that occurs in the lower part of the eyeball impractical. This procedure

  • is usually combined with cryopexy or laser photocoagulation. Pneumatic retinopexy has

  • significantly lower success rates compared to scleral buckle surgery and vitrectomy.

  • Some initially successful cases will fail during the weeks and months after surgery.

  • In some of the failed cases, an area of the retina which was healthy and attached prior

  • to the initial pneumatic retinopexy repair procedure develops new tears and/or becomes

  • detached. Vitrectomy 

  • Vitrectomy is an increasingly used treatment for retinal detachment. It involves the removal

  • of the vitreous gel and is usually combined with filling the eye with either a gas bubble

  • or silicone oil. An advantage of using gas in this operation is that there is no myopic

  • shift after the operation and gas is absorbed within a few weeks. Silicon oil, if filled

  • needs to be removed after a period of 2–8 months depending on surgeon's preference.

  • Silicone oil is more commonly used in cases associated with proliferative vitreo-retinopathy.

  • A disadvantage is that a vitrectomy always leads to more rapid progression of a cataract

  • in the operated eye. In many places vitrectomy is the most commonly performed operation for

  • the treatment of retinal detachment. Results of surgery

  • 85 percent of cases will be successfully treated with one operation with the remaining 15 percent

  • requiring 2 or more operations. After treatment patients gradually regain their vision over

  • a period of a few weeks, although the visual acuity may not be as good as it was prior

  • to the detachment, particularly if the macula was involved in the area of the detachment.

  • Epidemiology

  • The incidence of retinal detachment in otherwise normal eyes is around 5 new cases in 100,000

  • persons per year. Detachment is more frequent in middle-aged or elderly populations, with

  • rates of around 20 in 100,000 per year. The lifetime risk in normal individuals is about

  • 1 in 300. Asymptomatic retinal breaks are present in about 6% of eyes in both clinical

  • and autopsy studies. Retinal detachment is more common in people

  • with severe myopia, in whom the retina is more thinly stretched. In such patients, lifetime

  • risk rises to 1 in 20. About two-thirds of cases of retinal detachment occur in myopics.

  • Myopic retinal detachment patients tend to be younger than non-myopic ones.

  • Retinal detachment is more frequent after surgery for cataracts. The estimated long-term

  • prevalence of retinal detachment after cataract surgery is in the range of 5 to 16 per 1000

  • cataract operations, but is much higher in patients who are highly myopic, with a prevalence

  • of up to 7% being reported in one study. One study found that the probability of experiencing

  • retinal detachment within 10 years of cataract surgery may be about 5 times higher than in

  • the absence of treatment. Tractional retinal detachments can also occur

  • in patients with proliferative diabetic retinopathy or those with proliferative retinopathy of

  • sickle cell disease. In proliferative retinopathy, abnormal blood vessels 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, leading to tractional retinal detachment.

  • Although retinal detachment usually occurs in just one eye, there is a 15% chance of

  • it developing in the other eye, and this risk increases to 25–30% in patients who have

  • had a retinal detachment and cataracts extracted from both eyes.

  • Prognosis Up until the early 20th century, the prognosis

  • for rhegmatogenous retinal detachment was very poor, and no effective treatments were

  • available. Currently, about 95 percent of cases of retinal detachment can be repaired

  • successfully. Treatment failures usually involve either the failure to recognize all sites

  • of detachment, the formation of new retinal breaks, or proliferative vitreoretinopathy.

  • Involvement of the macula portends a worse prognosis. In cases where the macula is not