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CNV is conventionally treated with intravitreal injections of angiogenesis inhibitors (also known as "anti-VEGF" drugs) to control neovascularization and reduce the area of fluid below the retinal pigment epithelium. Angiogenesis inhibitors include pegaptanib, ranibizumab and bevacizumab (known by a variety of trade names, such as Macugen, Avastin or Lucentis). These inhibitors slow or stop the formation of new blood vessels (angiogenesis), typically by binding to or deactivating the transmission of vascular endothelial growth factor ('VEGF'), a signal protein produced by cells to stimulate formation of new blood vessels. The effectiveness of angiogenesis inhibitors has been shown to significantly improve visual prognosis with CNV, the recurrence rate for these neovascular areas remains high.
CNV may also be treated with photodynamic therapy coupled with a photosensitive drug such as verteporfin (Visudyne). The drug is given intravenously. It is then activated in the eye by a laser light. The drug destroys the new blood vessels, and prevents any new vessels forming by forming thrombi.
There are also surgical treatments for far-sightedness:
- Photorefractive keratectomy (PRK)
- Laser assisted in situ keratomileusis (LASIK)
- Refractive lens exchange (RLE)
- Laser epithelial keratomileusis (LASEK)
The simplest form of treatment for far-sightedness is the use of corrective lenses, eyeglasses or contact lenses. Eyeglasses used to correct far-sightedness have convex lenses.
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.
Corneal collagen cross-linking is a developing treatment which aims to strengthen the cornea, however, according to a 2015 Cochrane review, there is insufficient evidence to determine if it is useful in keratoconus.
In 2016, the US Food and Drug Administration approved riboflavin ophthalmic solution and KXL system for crosslinking based on three 12-month clinical trials.
Colobomas of the iris may be treated in a number of ways. A simple cosmetic solution is a specialized cosmetic contact lens with an artificial pupil aperture. Surgical repair of the iris defect is also possible. Surgeons can close the defect by stitching in some cases. More recently artificial iris prosthetic devices such as the Human Optics artificial iris have been used successfully by specialist surgeons. This device cannot be used if the natural lens is in place and is not suitable for children. Suture repair is a better option where the lens is still present.
Vision can be improved with glasses, contact lenses or even laser eye surgery but may be limited if the retina is affected or there is amblyopia.
A Cochrane review found conjunctival autograft surgery was less likely to have reoccurrence of the pterygium at 6 months compared to amniotic membrane transplant. More research is needed to determine which type of surgery resulted in better vision or quality of life. The additional use of mitomycin C is of unclear effect. Radiotherapy has also be used in an attempt to reduce the risk of recurrence.
Pingueculae may enlarge slowly over time, but are a benign condition, usually requiring no treatment. Artificial tears may help to relieve discomfort, if it occurs. If cosmesis is a concern, surgical excision is sometimes done. Occasionally, a pinguecula may become inflamed, a condition called pingueculitis. The cause of pingueculitis is unknown and there are no known infectious agents associated with it. If an inflamed pinguecula is causing discomfort or cosmetic concerns, it may be treated with an anti-inflammatory agent, such as prednisolone drops.
Pterygium typically do not require surgery unless it grows to such an extent that it causes visual problems. Some of the symptoms such as irritation can be addressed with artificial tears. Surgery may also be considered for unmanageable symptoms.
In early stages of keratoconus, glasses or soft contact lenses can suffice to correct for the mild astigmatism. As the condition progresses, these may no longer provide the person with a satisfactory degree of visual acuity, and most practitioners will move to manage the condition with rigid contact lenses, known as rigid, gas-permeable, (RGP) lenses. RGP lenses provide a good level of visual correction, but do not arrest progression of the condition.
In people with keratoconus, rigid contact lenses improve vision by means of tear fluid filling the gap between the irregular corneal surface and the smooth regular inner surface of the lens, thereby creating the effect of a smoother cornea. Many specialized types of contact lenses have been developed for keratoconus, and affected people may seek out both doctors specialized in conditions of the cornea, and contact lens fitters who have experience managing people with keratoconus. The irregular cone presents a challenge and the fitter will endeavor to produce a lens with the optimal contact, stability and steepness. Some trial-and-error fitting may prove necessary.
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 (SF or CF gas) or silicone oil (PDMS). 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. PDMS, if used, 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 (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. A recent Cochrane Review assessing various tamponade agents for patients with retinal detachment associated with PVR found that patients treated with CF gas and standard silicone oil had visual and anatomic advantages over patients using SF. Heavy silicone oil did not show any advantages over regular silicone oil.
It can be treated with laser coagulation, and more commonly with medication that stops and sometimes reverses the growth of blood vessels.
A randomized control trial found that bevacizumab and ranibizumab had similar efficacy, and reported no significant increase in adverse events with bevacizumab. A 2014 Cochrane review found that the systemic safety of bevacizumab and ranibizumab are similar when used to treat neovascular AMD, except for gastrointestinal disorders. Bevacizumab however is not FDA approved for treatment of macular degeneration. A controversy in the UK involved the off-label use of cheaper bevacizumab over the approved, but expensive, ranibizumab. Ranibizumab is a smaller fragment, Fab fragment, of the parent bevacizumab molecule specifically designed for eye injections. Other approved antiangiogenic drugs for the treatment of neo-vascular AMD include pegaptanib and aflibercept.
The American Academy of Ophthalmology practice guidelines do not recommend laser coagulation therapy for macular degeneration, but state that it may be useful in people with new blood vessels in the choroid outside of the fovea who don't respond to drug treatment. There is strong evidence that laser coagulation will result in the disappearance of drusen but does not affect choroidal neovascularisation. A 2007 Cochrane review on found that laser photocoagulation of new blood vessels in the choroid outside of the fovea is effective and economical method, but that the benefits are limited for vessels next to or below the fovea.
Photodynamic therapy has also been used to treat wet AMD. The drug verteporfin is administered intravenously; light of a certain wavelength is then applied to the abnormal blood vessels. This activates the verteporfin destroying the vessels.
Cataract surgery could possibly improve visual outcomes for people with AMD, though there have been concerns of surgery increasing the progression of AMD. A randomized controlled trial found that people who underwent immediate cataract surgery (within 2 weeks) had improved visual acuity and better quality of life outcomes than those who underwent delayed cataract surgery (6 months).
No medical or surgical treatment is available for this condition.
Anti-muscarinic topical medications in children under 18 years of age may slow the worsening of myopia. These treatments include pirenzepine gel, cyclopentolate eye drops, and atropine eye drops. While these treatments were shown to be effective in slowing the progression of myopia, side effects included light sensitivity and near blur.
Scleral reinforcement surgery is aimed to cover the thinning posterior pole with a supportive material to withstand intraocular pressure and prevent further progression of the posterior staphyloma. The strain is reduced, although damage from the pathological process cannot be reversed. By stopping the progression of the disease, vision may be maintained or improved.
Treatment can occur in two ways: treating symptoms and treating the deficiency. Treatment of symptoms usually includes the use of artificial tears in the form of eye drops, increasing the humidity of the environment with humidifiers, and wearing wraparound glasses when outdoors. Treatment of the deficiency can be accomplished with a Vitamin A or multivitamin supplement or by eating foods rich in Vitamin A. Treatment with supplements and/or diet can be successful until the disease progresses as far as corneal ulceration, at which point only an extreme surgery can offer a chance of returning sight.
Mild conjunctivochalasis can be asymptomatic and in such cases does not require treatment. Lubricating eye drops can be tried but do not often work.
If discomfort persists after standard dry eye treatment and anti-inflammatory therapy, surgery can be undertaken to remove the conjunctival folds and restore a smooth tear film. This conjunctivoplasty surgery to correct conjunctivochalasis typically involves resection of an ellipse-shaped segment of conjunctiva just inferior to the lower lid margin, and is usually followed either by suturing or amniotic membrane graft transplantation to close the wound.
Untreated glaucoma leads to total blindness. Surgical treatment is required. Presently-utilized surgical procedures include goniotomy, trabeculotomy, or trabeculectomy.
How refractive errors are treated or managed depends upon the amount and severity of the condition. Those who possess mild amounts of refractive error may elect to leave the condition uncorrected, particularly if the patient is asymptomatic. For those who are symptomatic, glasses, contact lenses, refractive surgery, or a combination of the three are typically used.
Strategies being studied to slow worsening include adjusting working conditions, increasing the time children spend outdoors, and special types of contact lenses. In children special contact lenses appear to slow worsening of nearsightedness.
Prophylaxis consists of periodic administration of Vitamin A supplements. WHO recommended schedule, which is universally recommended is as follows:
- Infants 6–12 months old and any older children weighing less than 8 kg - 100,000 IU orally every 3–6 months
- Children over 1 year and under 6 years of age - 200,000 IU orally every 6 months
- Infants less than 6 months old, who are not being breastfed - 50,000 IU orally should be given before they attain the age of 6 months
Because SO is so rarely encountered following eye injury, even when the injured eye is retained, the first choice of treatment may not be enucleation or evisceration, especially if there is a chance that the injured eye may regain some function. Additionally, with current advanced surgical techniques, many eyes once considered nonviable now have a fair prognosis.
However, only if the injured eye has completely lost its vision and has no potential for any visual recovery, prevention of SO is done by enucleation of the injured eye preferably within the first 2 weeks of injury. Evisceration—the removal of the contents of the globe while leaving the sclera and extraocular muscles intact—is easier to perform, offers long-term orbital stability, and is more aesthetically pleasing, i.e., a greater measure of movement of the prosthesis and thus a more natural appearance. There is concern, however, that evisceration may lead to a higher incidence of SO compared to enucleation. Several retrospective studies involving over 3000 eviscerations, however, have failed to identify a single case of SO.
Once SO is developed, Immunosuppressive therapy is the mainstay of treatment. When initiated promptly following injury, it is effective in controlling the inflammation and improving the prognosis. Mild cases may be treated with local application of corticosteroids and pupillary dilators. More severe or progressive cases require high-dose systemic corticosteroids for months to years. Patients who become resistant to corticosteroids or develop side effects of long-term corticosteroid therapy (osteoporosis and pathologic fractures, mental status changes, etc.), may be candidates for therapy with chlorambucil, cyclophosphamide, or ciclosporin.
Chorioretinitis is usually treated with a combination of corticosteroids and antibiotics. However, if there is an underlying cause such as HIV, specific therapy can be started as well.
A 2012 Cochrane Review found weak evidence suggesting that ivermectin could result in reduced chorioretinal lesions in patients with onchocercal eye disease. More research is needed to support this finding.
Treatment of choroid plexus carcinoma depends on the location and severity of the tumor. Possible interventions include inserting shunts, surgical resection, radiotherapy, and chemotherapy. Inserting a shunt could help to drain the CSF and relieve pressure on the brain. The best outcomes occur when total resection of the tumor is combined with adjuvant chemotherapy and radiotherapy. In the event of subtotal resection or widespread leptomeningeal disease, craniospinal irradiation is often used.
Astigmatism may be corrected with eyeglasses, contact lenses, or refractive surgery. Various considerations involving eye health, refractive status, and lifestyle determine whether one option may be better than another. In those with keratoconus, certain contact lenses often enable patients to achieve better visual acuity than eyeglasses. Once only available in a rigid, gas-permeable form, toric lenses are now available also as soft lenses.
Laser eye surgery (LASIK and PRK) is successful in treating astigmatism.
Treatment of lagopthalmos can include both supportive care methods as well as surgical. If unable to receive surgery, artificial tears should be administered at least four times a day to the cornea to preserve the tear film. Leading up to a surgery, a patient can undergo a tarsorrhaphy which partially sews the eye shut temporarily to further protect the cornea as the patient waits for care. Multiple surgical treatments exist for Lagopthalmos but the most prevalent method includes weighing the upper eyelid down by surgically inserting a gold plate. Due to possible complications in conjunction with both the upper and lower eyelid, it might also be required to undergo a second surgery to tighten and elevate the lower eyelid to ensure both the upper and lower eyelids can fully close and protect the cornea.