Retinal detachment is a disorder of the
eyeEyes are organs that detect light, and send electrical impulses along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system...
in which the
retinaThe vertebrate retina is a light sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to
vision lossVision loss or visual loss is the absence of vision where it existed before, which can happen either acutely or chronically...
and
blindnessBlindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
. It is a
medical emergencyA medical emergency is an injury or illness that is acute and poses an immediate risk to a person's life or long term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies can be dealt with by the...
.
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.
Retinal detachment is a disorder of the
eyeEyes are organs that detect light, and send electrical impulses along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system...
in which the
retinaThe vertebrate retina is a light sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to
vision lossVision loss or visual loss is the absence of vision where it existed before, which can happen either acutely or chronically...
and
blindnessBlindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
. It is a
medical emergencyA medical emergency is an injury or illness that is acute and poses an immediate risk to a person's life or long term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies can be dealt with by the...
.
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 nerveThe optic nerve, also called cranial nerve II, transmits visual information from the retina to the brain.-Anatomy:The optic nerve is the second of twelve paired cranial nerves but is considered to be part of the central nervous system as it is derived from an outpouching of the diencephalon during...
. Occasionally,
posterior vitreous detachmentA posterior vitreous detachment is a condition of the eye in which the vitreous humour separates from the retina.-Causes:The vitreous humor fills the eye behind the lens. At birth it is attached to the retina...
, 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.
Types
- Rhegmatogenous retinal detachment – A rhegmatogenous retinal detachment occurs due to a hole, tear, or 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.
- 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.
A substantial 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.
Prevalence
The risk of retinal detachment in otherwise normal eyes is around 5 in 100,000 per year. Detachment is more frequent in the middle-aged or elderly population with rates of around 20 in 100,000 per year. The lifetime risk in normal eyes is about 1 in 300.
- Retinal detachment is more common in those with severe myopia
Myopia , also called nearsightedness or shortsightedness, is a refractive defect of the eye in which collimated light produces image focus in front of the retina when accommodation is relaxed....
(above 5–6 diopters), as their eyes are longer and the retina is stretched thin. The lifetime risk increases to 1 in 20. Myopia is associated with 67% of retinal detachment cases. Patients suffering from a detachment related to myopia tend to be younger than non-myopic detachment patients.
- Retinal detachment can occur more frequently after surgery for cataracts. The estimated of risk of retinal detachment after cataract surgery is 5 to 16 per 1000 cataract operations. The risk may be much higher in those who are highly myopic, with a frequency of 7% reported in one study. 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.
- Tractional retinal detachments can also occur in patients with proliferative diabetic retinopathy
Diabetic retinopathy is retinopathy caused by complications of diabetes mellitus, which can eventually lead to blindness....
or those with proliferative retinopathy of sickle cell disease. 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.
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.
Symptoms
A retinal detachment is commonly preceded by a
posterior vitreous detachmentA posterior vitreous detachment is a condition of the eye in which the vitreous humour separates from the retina.-Causes:The vitreous humor fills the eye behind the lens. At birth it is attached to the retina...
which gives rise to these symptoms:
- flashes of light (photopsia
Photopsia is the presence of perceived flashes of light. It is most commonly associated with posterior vitreous detachment, migraine with aura, migraine aura without headache, retinal break or detachment, occipital lobe infarction and sensory deprivation .This condition has also been identified as...
) – very brief in the extreme peripheral (outside of center) 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 (scale, edge of the wall, road, etc.) that suddenly appear curved (positive Amsler grid
The Amsler grid, used since 1945, is a grid of horizontal and vertical lines used to monitor a person's central visual field. The grid was developed by Marc Amsler, a Swiss ophthalmologist. It is a diagnostic tool that aids in the detection of visual disturbances caused by changes in the retina,...
test)
- central visual loss
Treatment
There are several methods of treating a detached retina which all depend on finding and closing the holes (tears) which have formed in the retina.
- In this treatment, Silicone Oil is a sterile, colorless liquid injected into the eye and mechanically holds the retina in place until it reattaches. The oil is not intended to remain in the eye permanently and is usually removed within a year. This treatment has shown to be particularly effective in retinal detachment related to Cytomegalovirus secondary to AIDS.
- Cryopexy and Laser Photocoagulation
- Cryotherapy
Cryosurgery is the application of extreme cold to destroy abnormal or diseased tissue. The term comes from the Greek words cryo and surgery meaning "hand work" or "handiwork"....
(freezing) and laser photocoagulationLaser photocoagulation surgery is used to treat a number of eye diseases and has become widely used in recent decades. During the procedure, which is usually performed on an outpatient basis, a laser is used to finely cauterize ocular blood vessels to attempt to bring about various therapeutic...
are treatments used to create a scar/adhesion around the retinal hole to prevent fluid from entering the hole and accumulating behind the retina and exacerbating the retinal detachment. Cryopexy and photocoagulation are generally interchangeable. However, cryopexy is generally used in instances where there is a large amount of fluid behind the hole; laser retinopexy is not effective.
- Scleral buckle
A scleral buckle is one of several ophthalmologic procedures that can be used to repair a retinal detachment. Retinal detachments are usually caused by retinal tears, and a scleral buckle can be used to close the retinal break....
surgery is an established treatment in which the eye surgeon sews one or more silicone bands (bands, tyres) to the outside of the eyeball. The bands push the wall of the eye inward against the retinal hole, closing the hole and allowing the retina to re-attach. CryotherapyCryosurgery is the application of extreme cold to destroy abnormal or diseased tissue. The term comes from the Greek words cryo and surgery meaning "hand work" or "handiwork"....
(freezing) or laser photocoagulationLaser photocoagulation surgery is used to treat a number of eye diseases and has become widely used in recent decades. During the procedure, which is usually performed on an outpatient basis, a laser is used to finely cauterize ocular blood vessels to attempt to bring about various therapeutic...
has to be applied around the retinal break/hole. The bands do not usually have to be removed. 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 to U-shaped tears or Fishmouth tears and posterior breaks. Circumferential scleral buckle indicated to multiple breaks, anterior breaks and wide breaks. Encircling buckles indicated to breaks more than 2 quadrant of retinal area, lattice degeration located on more than 2 quadrant of retinal area, undetecable breaks, proliferative vitreous retinopathy and inexperienced surgeon .
- 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 (SF6 or C3F8 gas) 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
Surface tension is a property of the surface of a liquid. It is what causes the surface portion of liquid to be attracted to another surface, such as that of another portion of liquid .Applying Newtonian physics to the forces that arise due to surface tension accurately predicts many liquid behaviors...
of the air/water interface seals the hole in the retina, and allows the retinal pigment epithelium to pump the subretinal space dry and pull 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.
- Vitrectomy
Vitrectomy is a surgery to remove some or all of the vitreous humor from the eye. Anterior vitrectomy entails removing small portions of the vitreous from the front structures of the eye - often because these are tangled in an intraocular lens or other structures...
is an increasingly used treatment for retinal detachment in countries with modern healthcare systems. It involves the removal of the vitreous gel and is usually combined with filling the eye with either a gas bubble (SF6Sulfur hexafluoride is an inorganic, colorless, odorless, non-toxic and non-flammable gas . has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule. Typical for a nonpolar gas, it is poorly soluble in water but soluble in...
or C3F8 gas) or silicon oil. Advantages 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 (PDMS), if filled needs to removed after a period of 2–8 months depending on surgeon's preference. Silicon oil is more commonly used in cases associated with proliferative vitreo-retinopathy (PVR). 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.
- Ignipuncture
Ignipuncture is the original procedure of closing a retina break in retinal separation by transfixation of the break with cautery. The procedure was pioneered and named by Jules Gonin in the early 1900s...
is an outdated procedure that involves cauterizationThe medical practice or technique of cauterization is a medical term describing the burning of part of a body to remove or close off a part of it in a process called cautery, which destroys some tissue
of the retina with a very hot pointed instrument. It was pioneered and named by Jules GoninJules Gonin was a Professor of Ophthalmology in Lausanne who pioneered the procedure of ignipuncture, the first successful surgery for the treatment of retinal detachments.-External links:** at www.ascrs.org...
in the early 1900s.
After treatment patients gradually regain their vision over a period of a few weeks, although the visual acuityVisual acuity is acuteness or clearness of vision, especially form vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
may not be as good as it was prior to the detachment, particularly if the maculaThe sonya or dean is an oval-shaped highly pigmented yellow spot near the center of the retina of the human eye. It has a diameter of around 5 mm and is often histologically defined as having two or more layers of ganglion cells...
was involved in the area of the detachment. However, if left untreated, total blindnessBlindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
could occur in a matter of days.
Prevention
Retinal detachment can sometimes be prevented. The most effective means is by educating people to seek ophthalmic medical attention if they suffer symptoms suggestive of a posterior vitreous detachmentA posterior vitreous detachment is a condition of the eye in which the vitreous humour separates from the retina.-Causes:The vitreous humor fills the eye behind the lens. At birth it is attached to the retina...
. 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. Some doctors recommend avoiding activities that
increase pressure in the eye, including diving, skydiving, again with little supporting evidence. According to one medical website, retinal detachment does not happen as a result of straining your eyes, bending or, heavy lifting. Therefore, heavy weightlifting would appear to be fine. However, two recent scientific articles have noted cases of retinal detachment or maculopathy due to weightlifting (specifically with the Valsalva methodThe Valsalva maneuver or Valsalva manoeuvre is performed by forcible exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut...
), and a third documented an increase in blood pressureBlood pressure is the pressure exerted by circulating blood on the walls of blood vessels, and is one of the principal vital signs. During each heartbeat, BP varies between a maximum and a minimum pressure...
in the eye during weightlifting . Moreover, a recent case-control study focusing on myopic subjects supports the hypothesis that heavy lifting (or manual handling) requiring Valsalva maneuver may be a risk factor for retinal detachment .
Activities that involve sudden acceleration or deceleration also increase eye pressure and are discouraged by some doctors. These include bungee jumping and drag racing,
External links