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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
Surgeons can remove or peel the membrane through the sclera and improve vision by 2 or more Snellen lines. Usually the vitreous is replaced at the same time with clear (BSS) fluid, in a vitrectomy. Surgery is not usually recommended unless the distortions are severe enough to interfere with daily living, since there are the usual hazards of surgery, infections, and a possibility of retinal detachment. More common complications are high intraocular pressure, bleeding in the eye, and cataracts, which are the most frequent complication of vitrectomy surgery. Many patients will develop a cataract within the first few years after surgery. In fact, the visual distortions and diplopia created by cataracts may sometimes be confused with epiretinal membrane.
Risk factors such as UVB exposure and smoking can be addressed. Although no means of preventing cataracts has been scientifically proven, wearing sunglasses that counteract ultraviolet light may slow their development. While adequate intake of antioxidants (such as vitamins A, C, and E) has been thought to protect against the risk of cataracts, clinical trials have shown no benefit from supplements; though evidence is mixed, but weakly positive, for a potential protective effect of the nutrients lutein and zeaxanthin. Statin use is somewhat associated with a lower risk of nuclear sclerotic cataracts.
Vitrectomy is the common way to treat a macular hole. It is done by placing a gas bubble in the vitreous of the eye which helps flatten macular hole and holds it in place as the eye heals. The gas bubble slowly shrinks on its own. Treatment is also done using ocriplasmin.
Cryotherapy (freezing) or laser photocoagulation are occasionally used alone to wall off a small area of retinal detachment so that the detachment does not spread.
Therapy is not required or indicated in posterior vitreous detachment, unless there are associated retinal tears, which need to be repaired. In absence of retinal tears, the usual progress is that the vitreous humor will continue to age and liquefy and floaters will usually become less and less noticeable, and eventually most symptoms will completely disappear. Prompt examination of patients experiencing vitreous humor floaters combined with expeditious treatment of any retinal tears has been suggested as the most effective means of preventing certain types of retinal detachments.
Careful eye examination by an ophthalmologist or optometrist is critical for diagnosing symptomatic VMA. Imaging technologies such as optical coherence tomography (OCT) have significantly improved the accuracy of diagnosing symptomatic VMA.
A new FDA approved drug was released on the market late 2013. Jetrea (Brand name) or Ocriplasmin (Generic name) is the first drug of its kind used to treat vitreomacular adhension.
Mechanism of Action: Ocriplasmin is a truncated human plasmin with proteolytic activity against protein components of the vitreous body and vitreretinal interface. It dissolves the protein matrix responsible for the vitreomacular adhesion.
Adverse drug reactions: Decreased vision, potential for lens sublaxation, dyschromatopsia (yellow vision), eye pain, floaters, blurred vision.
New Drug comparison Rating gave Jetea a 5 indicating an important advance.
Previously, no recommended treatment was available for the patient with mild symptomatic VMA. In symptomatic VMA patients with more significant vision loss, the standard of care is pars plana vitrectomy (PPV), which involves surgically removing the vitreous from the eye, thereby surgically releasing the symptomatic VMA. In other words, vitrectomy induces PVD to release the traction/adhesion on the retina. An estimated 850,000 vitrectomy procedures are performed globally on an annual basis with 250,000 in the United States alone.
A standard PPV procedure can lead to serious complications including small-gauge PPV. Complications can include retinal detachment, retinal tears, endophthalmitis, and postoperative cataract formation. Additionally, PPV may result in incomplete separation, and it may potentially leave a nidus for vasoactive and vasoproliferative substances, or it may induce development of fibrovascular membranes. As with any invasive surgical procedure, PPV introduces trauma to the vitreous and surrounding tissue.
There are data showing that nonsurgical induction of PVD using ocriplasmin (a recombinant protease with activity against fibronectin and laminin) can offer the benefits of successful PVD while eliminating the risks associated with a surgical procedure, i.e. vitrectomy. Pharmacologic vitreolysis is an improvement over invasive surgery as it induces complete separation, creates a more physiologic state of the vitreomacular interface, prevents the development of fibrovascular membranes, is less traumatic to the vitreous, and is potentially prophylactic. As of 2012, ThromboGenics is still developing the ocriplasmin biological agent. Ocriplasmin is approved recently under the name Jetrea for use in the United States by the FDA.view.
An experimental test of injections of perfluoropropane (CF) on 15 symptomatic eyes of 14 patients showed that vitreomacular traction resolved in 6 eyes within 1 month and resolved in 3 more eyes within 6 months.
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.
Studies in the 1970s reported that the use of cannabis may lower intraocular pressure. In an effort to determine whether marijuana, or drugs derived from it, might be effective as a glaucoma treatment, the US National Eye Institute supported research studies from 1978 to 1984. These studies demonstrated some derivatives of marijuana lowered intraocular pressure when administered orally, intravenously, or by smoking, but not when topically applied to the eye.
In 2003, the American Academy of Ophthalmology released a position statement stating that cannabis was not more effective than prescription medications. Furthermore, no scientific evidence has been found that demonstrates increased benefits and/or diminished risks of cannabis use to treat glaucoma compared with the wide variety of pharmaceutical agents now available.
In 2012 the American Glaucoma Society published a position paper discrediting the use of cannabis as a legitimate treatment for elevated intraocular pressure, for reasons including short duration of action and side effects that limit many activities of daily living.
While surgeries do exist to correct for severe cases of floaters, there are currently no medications (including eye drops) that can correct for this vitreous deterioration. Floaters are often caused by the normal aging process and will usually disappear as the brain learns to ignore them. Looking up/down and left/right will cause the floaters to leave the direct field of vision as the vitreous humour swirls around due to the sudden movement. If floaters significantly increase in numbers and/or severely affect vision, then one of the below surgeries may be necessary.
Currently, insufficient evidence is available to compare the safety and efficacy of surgical vitrectomy with laser vitreolysis for the treatment of floaters. A 2017 Cochrane Review did not find any relevant studies that compared the two treatments.
Aggressive marketing campaigns are currently promoting the use of laser vitreolysis for the treatment of floaters. No strong evidence currently exists for the treatment of floaters with laser vitreolysis. Currently, the strongest available evidence comparing these two treatment modalities are retrospective case series.
In open-angle glaucoma, the typical progression from normal vision to complete blindness takes about 25 years to 70 years without treatment, depending on the method of estimation used. The intraocular pressure can also have an effect, with higher pressures reducing the time until blindness.
In the early stages, there are a few treatment options. Laser surgery or cryotherapy (freezing) can be used to destroy the abnormal blood vessels, thus halting progression of the disease. However, if the leaking blood vessels are clustered around the optic nerve, this treatment is not recommended as accidental damage to the nerve itself can result in permanent blindness. Although Coats' disease tends to progress to visual loss, it may stop progressing on its own, either temporarily or permanently. Cases have been documented in which the condition even reverses itself. However, once total retinal detachment occurs, sight loss is permanent in most cases. Removal of the eye (enucleation) is an option if pain or further complications arise.
While PEX itself is untreatable as of 2011, it is possible for doctors to minimize the damage to vision and to the optic nerves by the same medical techniques used to prevent glaucoma.
- Eyedrops. This is usually the first treatment method. Eyedrops can help reduce intraocular pressure within the eye. The medications within the eyedrops can include beta blockers (such as levobunolol or timolol) which slow the production of the aqueous humor. And other medications can increase its outflow, such as prostaglandin analogues (e.g. latanoprost). And these medicines can be used in various combinations. In most cases of glaucoma, eyedrops alone will suffice to solve the problem.
- Laser surgery. A further treatment is a type of laser therapy known as trabeculoplasty in which a high-energy laser beam is pointed at the trabecular meshwork to cause it to "remodel and open" and improve the outflows of the aqueous humor. These can be done as an outpatient procedure and take less than twenty minutes. One report suggests this procedure is usually effective.
- Eye surgery. Surgery is the treatment method of last resort if the other methods have not worked. It is usually effective at preventing glaucoma. Eye surgery on PEX patients can be subject to medical complications if the fibers which hold the lens have become weakened because of a buildup from the flakes; if the lens-holding fibers have weakened, then the lens may become loose, and complications from eye surgery may result. In such cases, it is recommended that surgeons act quickly to repair the phacodonesis before the lenses have dropped. A surgeon cuts an opening in the white portion of the eye known as the sclera, and removes a tiny area of the trabecular meshwork which enables the aqueous humor to discharge. This lowers the internal pressure within the eye and lessens the chance of future damage to the optic nerve. Cases with pseudophacodonesis and dislocated IOL have been increasing in number, according to one report. In cataract surgery, complications resulting from PEX include capsular rupture and vitreous loss.
- Drug therapy. There are speculations that if genetics plays a role in PEX, and if the specific genes involved can be identified, that possibly drugs can be developed to counteract these mutations or their effects. But such drugs have not been developed as of 2011.
Patients should continue to have regular eye examinations so that physicians can monitor pressure levels and check whether medicines are working.
Laser vitreolysis is a possible treatment option for the removal of vitreous strands and opacities (floaters). In this procedure an ophthalmic laser (usually a yttrium aluminium garnet (YAG) laser) applies a series of nanosecond pulses of low-energy laser light to evaporate the vitreous opacities and to sever the vitreous strands. During this process, the laser energy evaporates the collagen and hyaluronin molecules to form a gas. (It is important to note that the laser energy applied during vitreolysis treatment does not simply break the floater into smaller pieces. Instead, the laser energy converts the floater material to a gas, which is then absorbed into the eye.) The end result is that the floater is removed and/or reduced to a size that no longer impedes vision.
Vitreolysis is an outpatient procedure, which is much less invasive to the eye than a vitrectomy. Side effects may include cataract and intraocular pressure (IOP) spike. It offers a very good degree of patient satisfaction. It can also delay or obviate surgery.
The technique of using YAG lasers to treat vitreous strands and opacities dates to the 1980s, when professors Aron Rosa (Paris, France) and Franz Fankhauser (Berne, Switzerland), pioneers in the use of YAG lasers, both published on their success with vitreolysis.
In a Dutch study by Cees van der Windt, MD, and colleagues, 100 eyes, with PVD-related floaters persisting for more than nine months, were treated with YAG laser vitreolysis ("n" = 65) or pars plana vitrectomy ("n" = 35). After all eyes were treated, both the YAG and vitrectomy groups reported an improvement in vision at 85% and 90% respectively. Furthermore, over a follow-up period of eight years, no complications were observed among YAG-treated patients. These findings support those of two small-scale 1990s studies conducted by Tsai, et al., and Toczolowski, et al.. In both studies, a near 100% rate of floater removal was achieved with vitreolysis, and no intra- or post-operative complications occurred in any patient.
The number of floaters treated during a treatment session depends on the type of floater(s) and the laser energy required to treat the floater(s) (that is, to convert the floater material into a gas). During treatment, the ophthalmologist will monitor the level of laser energy used for each shot, as well as the total amount of energy delivered to the eye. In order to ensure safe, effective treatment with minimal patient discomfort, if these energy levels fall outside a predetermined range then any remaining floaters will need to be treated in a subsequent treatment session.
Every eye is different and there are a number of variables that affect the outcome of treatment. Some floaters, for example, are located too close to the retina and cannot be safely treated. The majority of patients will need to undergo two or three treatment sessions in order to achieve a satisfactory result.
When performed with a YAG laser designed specifically for vitreolysis, reported side effects and complications associated with vitreolysis are rare. However, YAG lasers have traditionally been designed for use in the anterior portion of the eye, i.e. posterior capsulotomy and iridotomy treatments. As a result, they often provide a limited view of the vitreous, which can make it difficult to identify the targeted floaters and membranes. They also carry a high risk of damage to surrounding ocular tissue. Accordingly, vitreolysis is not widely practised, being performed by very few specialists. One of them, John Karickhoff, has performed the procedure more than 1,400 times and claims a 90 percent success rate. However, the MedicineNet web site states that "there is no evidence that this [laser treatment] is effective. The use of a laser also poses significant risks to the vision in what is otherwise a healthy eye." A YAG laser optimized for use in the posterior segment, in addition to use in the anterior segment, is recommended for vitreolysis. In order to visualize the floater and target accordingly, the laser's light source must be positioned in the same optical axis as the ophthalmologist's visual axis. Most conventional YAG lasers, in contrast, use a lower angle of illuminating light. Whilst these lasers are well-suited to use in the anterior part of the eye, they are ill-equipped for use in the vitreous chamber, and thereby make it difficult for the ophthalmologist to visualize (and treat) the floater(s).
N-Acetylcarnosine drops have been investigated as a medical treatment for cataracts. The drops are believed to work by reducing oxidation and glycation damage in the lens, particularly reducing crystallin crosslinking. Some benefit has been shown in small manufacturer sponsored randomized controlled trials but further independent corroboration is still required.
Femtosecond laser mode-locking, used during cataract surgery, was originally used to cut accurate and predictable flaps in LASIK surgery, and has been introduced to cataract surgery. The incision at the junction of the sclera and cornea and the hole in capsule during capsulorhexis, traditionally made with a handheld blade, needle, and forceps, are dependent on skill and experience of the surgeon. Sophisticated three-dimensional images of the eyes can be used to guide lasers to make these incisions. can also then break up the cataract as in phacoemulsification.
Stem cells have been used in a clinical trial for lens regeneration in twelve children under the age of two with cataracts present at birth. The children were followed for six months, so it is unknown what the long-term results will be, and it is unknown if this procedure would work in adults.
The treatment method used depends on the cause of the hemorrhage. In most cases, the patient is advised to rest with the head elevated 30–45°, and sometimes to put patches over the eyes to limit movement prior to treatment in order to allow the blood to settle. The patient is also advised to avoid taking medications that cause blood thinning (such as aspirin or similar medications).
The goal of the treatment is to fix the cause of the hemorrhage as quickly as possible. Retinal tears are closed by Laser treatment or cryotherapy, and detached retinas are reattached surgically.
Even after treatment, it can take months for the body to clear all of the blood from the vitreous. In cases of vitreous hemorrhage due to detached retina,long-standing vitreous hemorrhage with a duration of more than 2–3 months, or cases associated with rubeosis iridis or glaucoma, a vitrectomy may be necessary to remove the standing blood in the vitreous.
Patients usually do not require treatment due to benign nature of the disease. In case cataract develops patients generally do well with cataract surgery.
Pigment dispersion syndrome (PDS) is an affliction of the eye that can lead to a form of glaucoma known as pigmentary glaucoma. It takes place when pigment cells slough off from the back of the iris and float around in the aqueous humor. Over time, these pigment cells can accumulate in the anterior chamber in such a way that it can begin to clog the trabecular meshwork (the major site of aqueous humour drainage), which can in turn prevent the aqueous humour from draining and therefore increases the pressure inside the eye. With PDS, the intraocular pressure tends to spike at times and then can return to normal. Exercise has been shown to contribute to spikes in pressure as well. When the pressure is great enough to cause damage to the optic nerve, this is called pigmentary glaucoma. As with all types of glaucoma, when damage happens to the optic nerve fibers, the vision loss that occurs is irreversible and painless.
This condition is rare, but occurs most often in Caucasians, particularly men, and the age of onset is relatively low: mid 20s to 40s. As the crystalline lens hardens with age, the lens zonules pull away from the iris and the syndrome lessens and stops. Most sufferers are nearsighted.
There is no cure yet, but pigmentary glaucoma can be managed with eye drops or treated with simple surgeries. One of the surgeries is the YAG laser procedure in which a laser is used to break up the pigment clogs, and reduce pressure. If caught early and treated, chances of glaucoma are greatly reduced. Sufferers are often advised not to engage in high-impact sports such as long-distance running or martial arts, as strong impacts can cause more pigment cells to slough off.
A 2016 Cochrane Review sought to determine the effectiveness of YAG laser iridotomy versus no laser iridotomy for pigment dispersion syndrome and pigmentary glaucoma, in 195 participants, across five studies. No clear benefits in preventing loss of visual field were found for eyes treated with peripheral laser iridotomy. There was weak evidence suggesting that laser iridotomy could be more effective in lowering intraocular pressure in eyes versus no treatment.
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.
Barrage laser is at times done prophylactically around a hole or tear associated with lattice degeneration in an eye at risk of developing a retinal detachment. It is not known if surgical interventions such as laser photocoagulation or cryotherapy is effective in preventing retinal detachment in patients with lattice degeneration or "asymptomatic" retinal detachment. Laser photocoagulation has been shown to reduce risks of retinal detachment in "symptomatic" lattice degeneration. There are documented cases wherein retina detached from areas which were otherwise healthy despite being treated previously with laser.
Optic pits themselves do not need to be treated. However, patients should follow up with their eye care professional annually or even sooner if the patient notices any visual loss whatsoever. Treatment of PVD or serous retinal detachment will be necessary if either develops in a patient with an optic pit.
Peri-ocular injection of corticosteroids (injection of corticosteroids very close but not into the eye). In resistant cases oral administration of corticosteroids, immunosuppressive drugs, and laser or cryotherapy of the involved area may be indicated.
Steroid implants have been explored as a treatment option for individuals with non-infectious uveitis. Research comparing fluocinolone acetonide intravitreal implants to standard-of-care treatments (prednisolone with immunosuppressive agents) found that while the steroid implant treatment possibly prevents the recurrence of uveitis, there may be adverse safety outcomes, such as the increased risk for needing cataract surgery and surgery to lower intraocular pressure.
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.
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.
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.