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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 have 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 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 people 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, but this relationship is not strong. In this study, obesity also appeared to increase the risk of retinal detachment. A high Body Mass Index (BMI) and elevated blood pressure have been identified as a risk factor in non-myopic individuals.
Genetic factors promoting local inflammation and photoreceptor degeneration may also be involved in the development of the disease.
Other risk factors include the following:
- Glaucoma
- AIDS
- Cataract surgery
- Diabetic retinopathy
- Eclampsia
- Family history of retinal detachment
- Homocysteinuria
- Malignant hypertension
- Metastatic cancer, which spreads to the eye (eye cancer)
- Retinoblastoma
- Severe myopia
- Smoking and passive smoking
- Stickler syndrome
- Von Hippel-Lindau disease
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 (above 5–6 diopters), 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 (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, 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.
This ocular pathology was first described by Iwanoff in 1865, and it has been shown to occur in about 7% of the population. It can occur more frequently in the older population with postmortem studies showing it in 2% of those aged 50 years and 20% in those aged 75 years.
There is no good evidence for any preventive actions, since it appears this is a natural response to aging changes in the vitreous. Posterior vitreous detachment (PVD) has been estimated to occur in over 75 per cent of the population over age 65, that PVD is essentially a harmless condition (although with some disturbing symptoms), and that it does not normally threaten sight. However, since epiretinal membrane appears to be a protective response to PVD, where inflammation, exudative fluid, and scar tissue is formed, it is possible that NSAIDs may reduce the inflammation response. Usually there are flashing light experiences and the emergence of floaters in the eye that herald changes in the vitreous before the epiretinal membrane forms g
Low vitamin C intake and serum levels have been associated with greater cataract rates. However, use of supplements of vitamin C has not demonstrated benefit.
The vitreous (Latin for "glassy") humor is a gel which fills the eye behind the lens. Between it and the retina is the vitreous membrane. With age the vitreous humor changes, shrinking and developing pockets of liquefaction, similar to the way a gelatin dessert shrinks and detaches from the edge of a pan. At some stage the vitreous membrane may peel away from the retina. This is usually a sudden event, but it may also occur slowly over months.
Age and refractive error play a role in determining the onset of PVD in a healthy person. PVD is rare in emmetropic people under the age of 40 years, and increases with age to 86% in the 90s. Several studies have found a broad range of incidence of PVD, from 20% of autopsy cases to 57% in a more elderly population of patients (average age was 83.4 years).
People with myopia (nearsightedness) greater than 6 diopters are at higher risk of PVD at all ages.
Posterior vitreous detachment does not directly threaten vision. Even so, it is of increasing interest because the interaction between the vitreous body and the retina might play a decisive role in the development of major pathologic vitreoretinal conditions, such as epiretinal membrane.
PVD may also occur in cases of cataract surgery, within weeks or months of the surgery.
The vitreous membrane is more firmly attached to the retina anteriorly, at a structure called the vitreous base. The membrane does not normally detach from the vitreous base, although it can be detached with extreme trauma. However, the vitreous base may have an irregular posterior edge. When the edge is irregular, the forces of the vitreous membrane peeling off the retina can become concentrated at small posterior extensions of the vitreous base. Similarly, in some people with retinal lesions such as lattice retinal degeneration or chorio-retinal scars, the vitreous membrane may be abnormally adherent to the retina. If enough traction occurs the retina may tear at these points. If there are only small point tears, these can allow glial cells to enter the vitreous humor and proliferate to create a thin epiretinal membrane that distorts vision. In more severe cases, vitreous fluid may seep under the tear, separating the retina from the back of the eye, creating a retinal detachment. Trauma can be any form from a blunt force trauma to the face such as a boxer's punch or even in some cases has been known to be from extremely vigorous coughing or blowing of the nose.
Cigarette smoking has been shown to double the rate of nuclear sclerotic cataracts and triple the rate of posterior subcapsular cataracts. Evidence is conflicting over the effect of alcohol. Some surveys have shown a link, but others which followed people over longer terms have not.
Macular degeneration is a condition affecting the tissues lying under the retina, while a macular hole involves damage from within the eye, at the junction between the vitreous and the retina itself. There is no relationship between the two diseases. Depending upon the degree of attachment or traction between the vitreous and the retina, there may be risk of developing a macular hole in the other eye. In those cases where the vitreous has already become separated from the retinal surface, there is very little chance of developing a macular hole in the other eye. On the other hand, when the vitreous remains adherent and pulling on the macular region in both eyes, then there may be a greater risk of developing a hole in the second eye. In very rare instances, trauma or other conditions lead to the development of a macular hole. In the vast majority of cases, however, macular holes develop spontaneously. As a result, there is no known way to prevent their development through any nutritional or chemical means, nor is there any way to know who is at risk for developing a hole prior to its appearance in one or both eyes.
A posterior vitreous detachment (PVD) is a condition of the eye in which the vitreous membrane separates from the retina.
It refers to the separation of the posterior hyaloid membrane from the retina anywhere posterior to the vitreous base (a 3–4 mm wide attachment to the ora serrata).
The condition is common for older adults; over 75% of those over the age of 65 develop it. Although less common among people in their 40s or 50s, the condition is not rare for those individuals. Some research has found that the condition is more common among women.
No particular risk factors have been conclusively identified; however, there have been a few reports that demonstrate an autosomal dominant pattern of inheritance in some families. Therefore, a family history of optic pits may be a possible risk factor.
Optic pits occur equally between men and women. They are seen in roughly 1 in 10,000 eyes, and approximately 85% of optic pits are found to be unilateral (i.e. in only one eye of any affected individual). About 70% are found on the temporal side (or lateral one-half) of the optic disc. Another 20% are found centrally, while the remaining pits are located either superiorly (in the upper one-half), inferiorly (in the lower one-half), or nasally (in the medial one-half towards the nose).
As one gets older, pockets of fluid can develop in the vitreous. When these pockets develop near the back of the eye, the vitreous can pull away from the retina and possibly tear it. Posterior vitreous detachment accounts for 3.7–11.7% of vitreous hemorrhage cases.
Less common causes of vitreous hemorrhage make up 6.4–18% of cases, and include:
- Proliferative sickle cell retinopathy
- Macroaneurysm
- Age-related macular degeneration
- Terson syndrome
- Retinal neovascularization as a result of branch or central retinal vein occlusion
- Other – about 7 cases in 100,000 have no known cause attributed to them.
CSR is a fluid detachment of macula layers from their supporting tissue. This allows choroidal fluid to leak beneath the retina. The buildup of fluid seems to occur because of small breaks in the retinal pigment epithelium.
CSR is sometimes called "idiopathic CSR" which means that its cause is unknown. Nevertheless, stress appears to play an important role. An oft-cited but potentially inaccurate conclusion is that persons in stressful occupations, such as airplane pilots, have a higher incidence of CSR.
CSR has also been associated with cortisol and corticosteroids. Persons with CSR have higher levels of cortisol. Cortisol is a hormone secreted by the adrenal cortex which allows the body to deal with stress, which may explain the CSR-stress association. There is extensive evidence to the effect that corticosteroids (e.g. cortisone), commonly used to treat inflammations, allergies, skin conditions and even certain eye conditions, can trigger CSR, aggravate it and cause relapses. In a study documented by Indian Journal of Pharmacology, a young male was using Prednisolone and began to display subretinal fluid indicative of CSR. With the discontinuation of the steroid drop the subretinal fluid resolved and did not show any sign of recurrence. Thus indicating the steroid was the probable cause of the CSR. A study of 60 persons with Cushing's syndrome found CSR in 3 (5%). Cushing's syndrome is characterized by very high cortisol levels. Certain sympathomimetic drugs have also been associated with causing the disease.
Evidence has also implicated helicobacter pylori (see gastritis) as playing a role. It would appear that the presence of the bacteria is well correlated with visual acuity and other retinal findings following an attack.
Evidence also shows that sufferers of MPGN type II kidney disease can develop retinal abnormalities including CSR caused by deposits of the same material that originally damaged the glomerular basement membrane in the kidneys.
Vitreomacular adhesion (VMA) is a human medical condition where the vitreous gel (or simply vitreous) of the human eye adheres to the retina in an abnormally strong manner. As the eye ages, it is common for the vitreous to separate from the retina. But if this separation is not complete, i.e. there is still an adhesion, this can create pulling forces on the retina that may result in subsequent loss or distortion of vision. The adhesion in of itself is not dangerous, but the resulting pathological vitreomacular traction (VMT) can cause severe ocular damage.
The current standard of care for treating these adhesions is pars plana vitrectomy (PPV), which involves surgically removing the vitreous from the eye. A biological agent for non-invasive treatment of adhesions called ocriplasmin has been approved by the FDA on Oct 17 2012.
If the vitreous is firmly attached to the retina when it pulls away, it can tear the retina and create a macular hole. Also, once the vitreous has pulled away from the surface of the retina, some of the fibers can remain on the retinal surface and can contract. This increases tension on the retina and can lead to a macular hole. In either case, the fluid that has replaced the shrunken vitreous can then seep through the hole onto the macula, blurring and distorting central vision.
A recent study estimated that from 2002-2003 there were 27,152 injuries in the United States related to the wearing of eyeglasses. The same study concluded that sports-related injuries due to eyeglasses wear were more common in those under the age of 18 and that fall-related injuries due to eyeglasses wear were more common in those aged 65 or more. Although eyeglasses-related injuries do occur, prescription eyeglasses and non-prescription sunglasses have been found to "offer measurable protection which results in a lower incidence of severe eye injuries to those wearing [them]".
In India study conducted by Dr.Shukla, injuries are found more in n males(81%).This is true for both rural and urban population but in 0-10 age group, the difference between males and females is less.Females account for 28% injuries in this age group.However, in sedentary workers, farmers, labourers and industrial workers the male % is as high as 95%.Chemical injuries are the comments cause of bilateral injuries in the eye .
Over time, it is common for the vitreous within the human eye to liquify and collapse in processes known as syneresis and synchisis respectively. This creates fluid-filled areas that can combine to form pockets of vitreous gel that are mostly liquid with very small concentrations of collagen. If these liquid pockets are close enough to the interface between the vitreous gel and the retina, they can cause complete separation of the vitreous from the retina in a normally occurring process in older humans called posterior vitreous detachment (PVD). PVD in of itself is not dangerous and a natural process.
If the separation of the vitreous from the retina is not complete, areas of focal attachment or adhesions can occur, i.e. a VMA. The pulling forces or traction from this adhesion on the retinal surface can sometimes cause edema within the retina, damage to retinal blood vessels causing bleeding, or damage to the optic nerve causing disruption in the nerve signals sent to the brain for visual processing. It is important to note that while the VMA itself is not dangerous, the resultant pulling on the retina called vitreomacular traction (VMT) causes the above damage. The size and strength of the VMA determine the variety of resulting pathologies or symptoms.
VMA can also lead to the development of VMT/traction-related complications such as macular puckers and macular holes leading to distorted vision or metamorphopsia; epiretinal membrane; tractional macular oedema; myopic macular retinoschisis; visual impairment; blindness. The incidence of VMA is reported as high as 84% for patients with macular hole, 100% for patients with vitreomacular traction syndrome, and 56% in idiopathic epimacular membrane.
There are many causes of blurred vision:
- Use of atropine or other anticholinergics
- Presbyopia—Difficulty focusing on objects that are close. Common in the elderly. (Accommodation tends to decrease with age.)
- Cataracts—Cloudiness over the eye's lens, causing poor night-time vision, halos around lights, and sensitivity to glare. Daytime vision is eventually affected. Common in the elderly.
- Glaucoma—Increased pressure in the eye, causing poor night vision, blind spots, and loss of vision to either side. A major cause of blindness. Glaucoma can happen gradually or suddenly—if sudden, it is a medical emergency.
- Diabetes—Poorly controlled blood sugar can lead to temporary swelling of the lens of the eye, resulting in blurred vision. While it resolves if blood sugar control is reestablished, it is believed repeated occurrences promote the formation of cataracts (which are not temporary).
- Diabetic retinopathy—This complication of diabetes can lead to bleeding into the retina. Another common cause of blindness.
- Hypervitaminosis A—Excess consumption of vitamin A can cause blurred vision.
- Macular degeneration—Loss of central vision, blurred vision (especially while reading), distorted vision (like seeing wavy lines), and colors appearing faded. The most common cause of blindness in people over age 60.
- Eye infection, inflammation, or injury.
- Sjögren's syndrome, a chronic autoimmune inflammatory disease that destroys moisture producing glands, including lacrimal (tear)
- Floaters—Tiny particles drifting across the eye. Although often brief and harmless, they may be a sign of retinal detachment.
- Retinal detachment—Symptoms include floaters, flashes of light across your visual field, or a sensation of a shade or curtain hanging on one side of your visual field.
- Optic neuritis—Inflammation of the optic nerve from infection or multiple sclerosis. You may have pain when you move your eye or touch it through the eyelid.
- Stroke or transient ischemic attack
- Brain tumor
- Toxocara—A parasitic roundworm that can cause blurred vision
- Bleeding into the eye
- Temporal arteritis—Inflammation of an artery in the brain that supplies blood to the optic nerve.
- Migraine headaches—Spots of light, halos, or zigzag patterns are common symptoms prior to the start of the headache. A retinal migraine is when you have only visual symptoms without a headache.
- Myopia—Blurred vision may be a systemic sign of local anaesthetic toxicity
- Reduced blinking—Lid closure that occurs too infrequently often leads to irregularities of the tear film due to prolonged evaporation, thus resulting in disruptions in visual perception.
- Carbon monoxide poisoning—Reduced oxygen delivery can effect many areas of the body including vision. Other symptoms caused by CO include vertigo, hallucination and sensitivity to light.
The hyaloid artery, an artery running through the vitreous humour during the fetal stage of development, regresses in the third trimester of pregnancy. Its disintegration can sometimes leave cell matter.
No complications are encountered in most patients with lattice degeneration, although in young myopes, retinal detachment can occur. There are documented cases with macula-off retinal detachment in patients with asymptomatic lattice degeneration. Partial or complete vision loss almost always occurs in such cases. Currently there is no prevention or cure for lattice degeneration.
Patients with retinal tears may experience floaters if red blood cells are released from leaky blood vessels, and those with uveitis or vitritis, as in toxoplasmosis, may experience multiple floaters and decreased vision due to the accumulation of white blood cells in the vitreous humour.
Other causes for floaters include cystoid macular edema and asteroid hyalosis. The latter is an anomaly of the vitreous humour, whereby calcium clumps attach themselves to the collagen network. The bodies that are formed in this way move slightly with eye movement, but then return to their fixed position.
Multiple complications are known to occur following eye injury: corneal scarring, hyphema, iridodialysis, post-traumatic glaucoma, uveitis cataract, vitreous hemorrhage and retinal detachment. The complications risk is high with retinal tears, penetrating injuries and severe blunt trauma.
Uveitis refers to a large group of disorders which cause inflammation within the eye. A similar condition, iritis, usually refers to an inflammation involving the front structures of the eye associated with pain, redness, and sensitivity to light. In this discussion, uveitis could have these symptoms, but mainly consists of inflammation involving the back structures of the eye (the retina, choroid, and optic nerve). Inflammatory debris liberated into the vitreous leads to the visualization of floaters. If this liberation continues, the vision may become substantially hazy and blurred.
There are numerous conditions leading to uveitis, and many have floaters and blurred vision as predominant symptoms: sarcoidosis, toxoplasmosis chorioretinitis, ocular histoplasmosis, multifocal choroiditis, pars planitis, endophalmitis, syphilis, candidiasis, viral uveitis, Vogt-Koyanagi-Harada syndrome, and HIV related uveitis.
Distorted vision is a symptom with several different possible causes.