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Birdshot chorioretinopathy may show resistance to treatment. Immunosuppressant therapy along with oral corticosteroid has been somewhat effective in slowing down the progressive inflammation associated with the disorder, preserving visual integrity as much as possible. Long-term use of such medications must be closely monitored, however, due to the discomforting and potentially debilitating and life-threatening side-effects.
Immunosuppressive drugs such as the therapeutic monoclonal antibody daclizumab, ciclosporin and methotrexate have proven to be effective treatment options for birdshot chorioretinopathy. Substantial reduction and even stabilization of both vitreous inflammation and retinal vasculitis have been evident via electroretinography, during daclizumab (IL-2 receptor blocker) therapy. This is also supported by the observation of elevated levels of IL-2 in the eyes of patients. Loss of visual acuity unrelated to the inflammation caused by the disorder, however, often remains unchanged despite usage of the drug. This is reflected by the lack of difference in visual acuity and the vision-related quality of life among various treatment categories in birdshot patients. Contraindications and adverse side-effects are always a factor, as well.
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.
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.
Often, treatment is not necessary, because episcleritis is a self-limiting condition. Artificial tears may be used to help with irritation and discomfort. More severe cases can be treated with either topical corticosteroids or oral non-steroidal anti-inflammatory drugs.
Ketorolac, a topical NSAID, may be used, but it is not more effective than artificial tears and it causes more side effects.
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.
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.
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.
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)
Topical ciclosporin (topical ciclosporin A, tCSA) 0.05% ophthalmic emulsion is an immunosuppressant. The drug decreases surface inflammation. In a trial involving 1200 people, Restasis increased tear production in 15% of people, compared to 5% with placebo.
It should not be used while wearing contact lenses, during eye infections or in people with a history of herpes virus infections. Side effects include burning sensation (common), redness, discharge, watery eyes, eye pain, foreign body sensation, itching, stinging, and blurred vision. Long term use of ciclosporin at high doses is associated with an increased risk of cancer.
Cheaper generic alternatives are available in some countries.
Currently, there is not a treatment option for regaining vision by developing a new eye. There are, however, cosmetic options so the absence of the eye is not as noticeable. Typically, the child will need to go to a prosthetic specialist to have conformers fitted into the eye. Conformers are made of clear plastic and are fitted into the socket to promote socket growth and expansion. As the child's face grows and develops, the conformer will need to be changed. An expander may also be needed in anophthalmia to expand the socket that is present. The conformer is changed every few weeks the first two years of life. After that, a painted prosthetic eye can be fitted for the child's socket. The prosthetic eye can be cleaned with mild baby soap and water. Rubbing alcohol should be avoided because it may damage the prosthetic eye. Children need to be checked regularly to ensure the fit and size is appropriate.
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.
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.
The acute uveitis phase of VKH is usually responsive to high-dose oral corticosteroids; parenteral administration is usually not required. However, ocular complications may require an subtenon or intravitreous injection of corticosteroids or bevacizumab. In refractory situations, other immunosuppressives such as cyclosporine, or tacrolimus, antimetabolites (azathioprine, mycophenolate mofetil or methotrexate), or biological agents such as intravenous immunoglobulins (IVIG) or infliximab may be needed.
One form of LCA, patients with LCA2 bearing a mutation in the RPE65 gene, has been successfully treated in clinical trials using gene therapy. The results of three early clinical trials were published in 2008 demonstrating the safety and efficacy of using adeno-associated virus to deliver gene therapy to restore vision in LCA patients. In all three clinical trials, patients recovered functional vision without apparent side-effects. These studies, which used adeno-associated virus, have spawned a number of new studies investigating gene therapy for human retinal disease.
The results of a phase 1 trial conducted by the University of Pennsylvania and Children’s Hospital of Philadelphia and published in 2009 showed sustained improvement in 12 subjects (ages 8 to 44) with RPE65-associated LCA after treatment with AAV2-hRPE65v2, a gene replacement therapy. Early intervention was associated with better results. In that study, patients were excluded based on the presence of particular antibodies to the vector AAV2 and treatment was only administered to one eye as a precaution. A 2010 study testing the effect of administration of AAV2-hRPE65v2 in both eyes in animals with antibodies present suggested that immune responses may not complicate use of the treatment in both eyes.
Eye Surgeon Dr. Al Maguire and gene therapy expert Dr. Jean Bennett developed the technique used by the Children's Hospital.
Dr. Sue Semple-Rowland at the University of Florida has recently restored sight in an avian model using gene therapy.
Inflammation occurring in response to tears film hypertonicity can be suppressed by mild topical steroids or with topical immunosuppressants such as ciclosporin (Restasis). Elevated levels of tear NGF can be decreased with 0.1% prednisolone.
Diquafosol, an agonist of the P2Y2 purinogenic receptor, is approved in Japan for managing dry eye disease by promoting tear secretion.
Lifitegrast is a new drug that was approved by the FDA for the treatment of the condition in 2016.
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
Treatment is aimed at managing the symptoms of the disease. A form of laser eye surgery named keratectomy may help with the superficial corneal scarring. In more severe cases, a partial or complete corneal transplantation may be considered. However, it is common for the dystrophy to recur within the grafted tissue.
Early diagnosis, targeted treatment according to the severity of the disease, and regular monitoring of patients with neurotrophic keratitis are critical to prevent damage progression and the occurrence of corneal ulcers, especially considering that the deterioration of the condition is often poorly symptomatic.
The purpose of treatment is to prevent the progression of corneal damage and promote healing of the corneal epithelium. The treatment should always be personalized according to the severity of the disease. Conservative treatment is typically the best option.
In stage I, the least serious, treatment consists of the administration of preservative-free artificial tears several times a day in order to lubricate and protect the ocular surface, improving the quality of the epithelium and preventing the possible loss of transparency of the cornea.
In stage II, treatment should be aimed at preventing the development of corneal ulcers and promoting the healing of epithelial lesions. In addition to artificial tears, topical antibiotics may also be prescribed to prevent possible infections. Patients should be monitored very carefully since, being the disease poorly symptomatic, the corneal damage may progress without the patient noticing any worsening of the symptoms. Corneal contact lenses can also be used in this stage of the disease, for their protective action to improve corneal healing.
In the most severe forms (stage III), it is necessary to stop the progression towards corneal perforation: in these cases, a possible surgical treatment option is tarsorrhaphy, i.e. the temporary or permanent closure of the eyelids by means of sutures or botulinum toxin injection. This protects the cornea, although the aesthetic result of these procedures may be difficult to accept for patients. Similarly, a procedure that entails the creation of a conjunctival flap has been shown to be effective in the treatment of chronic corneal ulcers with or without corneal perforation. In addition, another viable therapeutic option is amniotic membrane graft, which has recently been shown to play a role in stimulating corneal epithelium healing and in reducing vascularisation and inflammation of the ocular surface . Other approaches used in severe forms include the administration of autologous serum eye drops.
Research studies have focused on developing novel treatments for neurotrophic keratitis, and several polypeptides, growth factors and neuromediators have been proposed[25]. Studies were conducted on topical treatment with Substance P and IGF-1 (insulin-like growth factor-1), demonstrating an effect on epithelial healing[26]. Nerve Growth Factor (NGF) play a role in the epithelial proliferation and differentiation and in the survival of corneal sensory nerves. Topical treatment with murine NGF showed to promote recovery of epithelial integrity and corneal sensitivity in NK patients[27]. Recently, a recombinant human nerve growth factor eye drop formulation has been developed for clinical use[28].
Cenegermin, a recombinant form of human NGF, has recently been approved in Europe in an eye drop formulation for neurotrophic keratitis.
If the proper actions are not taken to expand the orbit, many physical deformities can appear. It is important that if these deformities do appear, that surgery is not done until at least the first two years of life. Many people get eye surgery, such as upper eyelid ptosis surgery and lower eyelid tightening. These surgeries can restore the function of the surrounding structures like the eyelid in order to create the best appearance possible. This is more common with people who have degenerative anophthalmia.
Visual prognosis is generally good with prompt diagnosis and aggressive immunomodulatory treatment. Inner ear symptoms usually respond to corticosteroid therapy within weeks to months; hearing usually recovers completely. Chronic eye effects such as cataracts, glaucoma, and optic atrophy can occur. Skin changes usually persist despite therapy.
One treatment used is polyhexamethylene biguanide, PHMB.
Propamidine isethionate has also shown some effectiveness.
Another possible agent is chlorhexidine.
Keratoplasty may sometimes be required.
A combined regimen of propamidine, miconazole nitrate, and neomycin has also been suggested.
A recent Cochrane review found one study that compared the effectiveness of chlorhexidine eye drops against PHMB eye drops, for eyes with "Acanthamoeba" keratitis. The differences between treatments were not statistically significant; the review found that 86% of eyes treated with chlorhexidine eye drops reported a resolution of infection, compared to 78% of eyes treated with PHMB eye drops. The study also found that 71% of eyes treated with chlorhexidine eye drops reported improved visual acuity after treatment, compared to 57% of eyes in the PMGB group; these results were also not significant.
In case of corneal erosion, a doctor may prescribe eye drops and ointments to reduce the friction on the eroded cornea. In some cases, an eye patch may be used to immobilize the eyelids. With effective care, these erosions usually heal within three to seven days, although occasional sensations of pain may occur for the next six-to-eight weeks. As patients with LCD suffer with dry eyes as a result of erosion, a new technique involving the insertion of punctal plugs (both upper and lower) can reduce the amount of drops used a day, aiding ocular stability.
By about age 40, some people with lattice dystrophy will have scarring under the epithelium, resulting in a haze on the cornea that can greatly obscure vision. In this case, a corneal transplantation may be needed. There have been many cases in which teenage patients have had the procedure, which accounts for the change in severity of the condition from person to person.
Although people with lattice dystrophy have an excellent chance for a successful corneal transplantation, the disease may also arise in the donor cornea in as little as three years. In one study, about half of the transplant patients with lattice dystrophy had a recurrence of the disease between two and 26 years after the operation. Of these, 15 percent required a second corneal transplant. Early lattice and recurrent lattice arising in the donor cornea responds well to treatment with the excimer laser.
Phototherapeutic keratectomy (PTK) using [Excimer laser] can restore and preserve useful visual function for a significant period of time in patients with anterior corneal dystrophies.
Treatment options include contact lenses and intrastromal corneal ring segments for correcting refractive errors caused by irregular corneal surface, corneal collagen cross-linking to strengthen a weak and ectatic cornea, or corneal transplant for advanced cases.
Reis-Bücklers corneal dystrophy is not associated with any systemic conditions.
According to the American Optometric Association, the following steps can be taken to prevent "Acanthamoeba" keratitis:
- Always wash and dry your hands before handling contact lenses, ordinary water should never come in contact with your lenses.
- Rub and rinse the surface of the contact lens before storing.
- Use only sterile products recommended by your optometrist to clean and disinfect your lenses. Saline solution and rewetting drops are not designed to disinfect lenses.
- Avoid using tap water to wash or store contact lenses.
- Contact lens solution must be discarded upon opening the case, and fresh solution used each time the lens is placed in the case.
- Replace lenses using your doctor’s prescribed schedule.
- Do not sleep in contact lenses unless prescribed by your doctor and never after swimming.
- Never swap lenses with someone else.
- Never put contact lenses in your mouth.
- See your optometrist regularly for contact lens evaluation.