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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
Predisposing factors for Postoperative PVR are preoperative PVR, aphakia, high levels of vitreous proteins, duration of retinal detachment before corrective surgery, the size of the retinal hole or tear, intra-ocular inflammation, vitreous hemorrhage, and trauma to the eye. An equation to calculate the patient's risk for acquiring PVR is:
1 is added if the risk factor is present and 0 if the risk factor is absent. A patient is at a high risk for developing PVR is the PVR score is >6.33.
Familial transmission is now recognized in a small proportion of people with MacTel type 2; however, the nature of any related genetic defect or defects remains elusive. The MacTel genetic study team hopes that exome analysis in the affected population and relatives may be more successful in identifying related variants.
Although a variety of complex classification schemes are described in the literature, there are essentially two forms of macular telangiectasia: type 1 and type 2. Type 1 is typically unilateral and occurs almost exclusively in males after the age of 40.
Type 2 is mostly bilateral, occurs equally in males and females.
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.
Proliferative vitreoretinopathy (PVR) is a disease that develops as a complication of rhegmatogenous retinal detachment. PVR occurs in about 8–10% of patients undergoing primary retinal detachment surgery and prevents the successful surgical repair of rhegmatogenous retinal detachment. PVR can be treated with surgery to reattach the detached retina but the visual outcome of the surgery is very poor.
PVR was originally referred to as massive vitreous retraction and then as massive periretinal proliferation. The name Proliferative vitreo retinopathy was provided in 1989 by the Silicone Oil Study group. The name is derived from "proliferation" (by the retinal pigment epithelial and glial cells) and "vitreo retinopathy" to include the tissues which are affected, namely the vitreous humor (or simply vitreous) and the retina.
Cytomegalovirus (a type of herpes virus) is what causes cytomegalovirus retinitis. Other types of herpes viruses include herpes simplex viruses and Epstein-Barr virus. Once an individual is infected with these viruses they stay in the body for life. What triggers the virus to reactivate are the following (though CMV can also be congenital).
- Leukemia
- AIDS
- Immunosuppressive chemotherapy
Human cytomegalovirus (HCMV or CMV) is a DNA virus in the family "Herpesviridae" known for producing large cells with nuclear and cytoplasmic inclusions, CMV infects around 40% of the population worldwide.
Those areas infected by cytomegalovirus have cells evolve to necrosis, though inflammation within the retina is not great.
Rhegmatogenous retinal detachments can occur following the development of holes in areas of healed retinitis (retina may be atrophic). Proliferative vitreoretinopathy has been observed in cases of retinal detachment.
ROP prevalence varies, from 5–8% in developed countries with adequate neonatological facilities, to up to 30% in middle-income developing countries.
There is increasing evidence that ROP and blindness due to ROP are now public health problems in the middle income countries of Latin America, Eastern Europe and the more advanced economies in South East Asia and the Middle east region. In these countries ROP is often the most common cause of blindness in children. ROP is highly likely to become an increasing problem in India, China and other countries in Asia as these countries expand the provision of services for premature infants.
There is also evidence that the population of premature infants at risk of severe ROP varies depending on the level of neonatal intensive care being provided. In countries with high development indices and very low neonatal mortality rates (e.g. North America, western Europe), severe ROP is generally limited to extremely preterm infants i.e. those weighing less than 1 kg (2.2 lbs) at birth. At the other end of the development spectrum, countries with very low development indices and very high neonatal mortality rates (e.g. much of subSaharan Africa) ROP is rare as most premature babies do not have access to neonatal intensive care and so do not survive. Countries with moderate development indices are improving access to neonatal intensive care, and in these settings bigger, more mature babies are also at risk of severe ROP as neonatal care may be suboptimal i.e. those weighing 1.5–2 kg (3.3-4.4 lbs) at birth. These findings have two main implications: firstly, much can be done in countries with moderate development indices to improve neonatal care, to reduce the risk of severe ROP in bigger babies and increase survival of extremely preterm infants, and secondly, in these settings bigger more mature babies need to be included in ROP programs and examined regularly so as to detect those babies developing ROP requiring treatment.
In 2012, the World Health Organization published data on rates of preterm birth and the number of premature babies born in different regions of the world. This report contained three main findings:
- Premature birth has many different causes, and prevention is challenging,
- Prematurity is the most common cause of neonatal death in many countries, totaling as many as 1 million infants annually due to complications of preterm birth, and
- the number of preterm births is currently estimated to be 15 million, and increasing.
Stages 1 and 2 do not lead to blindness. However, they can progress to the more severe stages. Threshold disease is defined as disease that has a 50% likelihood of progressing to retinal detachment. Threshold disease is considered to be present when stage 3 ROP is present in either zone I or zone II, with at least 5 continuous or 8 total clock hours of disease, and the presence of "plus" disease. Progression to stage 4 (partial retinal detachment), or to stage 5 (total retinal detachment), will result in substantial or total loss of vision for the infant.
- Refractive errors (most common)
- Squint
- Amblyopia
- Retinal detachment and blindness
- Glaucoma
Familial exudative vitreoretinopathy (FEVR) ( ) is a genetic disorder affecting the growth and development of blood vessels in the retina of the eye. This disease can lead to visual impairment and sometimes complete blindness in one or both eyes. FEVR is characterized by exudative leakage and hemorrhage of the blood vessels in the retina, along with incomplete vascularization of the peripheral retina. The disease process can lead to retinal folds, tears, and detachments.
Treatment is based
on the stage of the disease. Stage 1 does not
require treatment and
should be observed. 4
Neovascularization
(stage 2) responds well
to laser ablation or
cryotherapy.2,4 Eyes
with retinal detachments (stages
3 through 5) require surgery, with
earlier stages requiring scleral
buckles and later stages ultimately
needing vitrectomy. 2,4
More recently, the efficacy of
anti-VEGF intravitreal injections
has been studied. In one study,
these injections, as an in adjunct
with laser, helped early stages
achieve stabilization, but further
investigation is needed.6