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Proper diagnosis is essential for optimal treatment. Bacterial corneal ulcer require intensive fortified antibiotic therapy to treat the infection. Fungal corneal ulcers require intensive application of topical anti-fungal agents. Viral corneal ulceration caused by herpes virus may respond to antivirals like topical acyclovir ointment instilled at least five times a day. Alongside, supportive therapy like pain medications are given, including topical cycloplegics like atropine or homatropine to dilate the pupil and thereby stop spasms of the ciliary muscle. Superficial ulcers may heal in less than a week. Deep ulcers and descemetoceles may require conjunctival grafts or conjunctival flaps, soft contact lenses, or corneal transplant. Proper nutrition, including protein intake and Vitamin C are usually advised. In cases of Keratomalacia, where the corneal ulceration is due to a deficiency of Vitamin A, supplementation of the Vitamin A by oral or intramuscular route is given. Drugs that are usually contraindicated in corneal ulcer are topical corticosteroids and anesthetics - these should not be used on any type of corneal ulcer because they prevent healing, may lead to superinfection with fungi and other bacteria and will often make the condition much worse.
Topical antibiotics are used at hourly intervals to treat infectious corneal ulcers. Cycloplegic eye drops are applied to give rest to the eye. Pain medications are given as needed. Loose epithelium and ulcer base can be scraped off and sent for culture sensitivity studies to find out the pathogenic organism. This helps in choosing appropriate antibiotics. Complete healing takes anywhere from about a few weeks to several months.
Refractory corneal ulcers can take a long time to heal, sometimes months. In case of progressive or non-healing ulcers, surgical intervention by an ophthalmologist with corneal transplantation may be required to save the eye. In all corneal ulcers it is important to rule out predisposing factors like diabetes mellitus and immunodeficiency.
Topical antibiotics may be reasonable.
One review has found that eye drops to numb the surface of the eye such as tetracaine improve pain; however, their safety is unclear. Another review did not find evidence of benefit and concluded there was not enough data on safety.
NSAID eye drops are also useful. A 2000 review found no good evidence to support medications that paralyze the iris. A 2017 review did not find evidence to suggest that topical NSAIDs would significantly reduce pain over standard-of-care treatments, but did find that NSAIDs could be associated with people using fewer pain medications by mouth.
A meta-analysis found evidence that does not support the use of patching.
Herpetic stromal keratitis is treated initially with prednisolone drops every 2 hours
accompanied by a prophylactic antiviral drug: either topical antiviral or an oral agent such as acyclovir or valacyclovir. The prednisolone drops are tapered every 1–2 weeks depending on the degree of clinical improvement. Topical antiviral medications are not absorbed by the cornea through an intact epithelium, but orally administered acyclovir penetrates an intact cornea and anterior chamber. In this context, oral acyclovir might benefit the deep corneal inflammation of disciform keratitis.
Treatment includes artificial tears and eye lubricants, stopping toxic medications, performing punctal occlusion, bandage contact lens and amniotic membrane transplant. These measures intend to improve corneal epithelial healing.
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.
Reduction of neovascularization has been achieved in rats by the topical instillation of commercially available triamcinolone and doxycycline.
Some evidence exists to suggest that the Angiotensin II receptor blocker drug telmisartan will prevent corneal neovascularization.
Recent treatment developments include topical application of bevacizumab, an anti-VEGF.
Oral Antibiotics: Ophthalmologists or optometrists may prescribe a low-dose, oral antibiotic such as Doxycycline.
Topical Antibiotics: If prescribed, topical creams or ointments can be applied after the cleansing of the lid margin. A small amount of antibiotic ophthalmic ointment is spread along the lid fissure with a swab or fingertip, while the eyes are closed. It is prescribed for use prior to bedtime to avoid blurred vision. Another method to reduce side effects of blepharitis are antibiotics such as erythromycin or sulfacetamide, which are used via eye drops, creams, or ointments on the eyelid margin. blepharitis caused by Demodex mites can be treated using a diluted solution of tea tree oil, via application by a cotton swab, for 5–10 minutes per day.
Steroid eyedrops/ointments: Eye drops or ointments containing corticosteroids are frequently used in conjunction with antibiotics and can reduce eyelid inflammation.
A presumptive diagnosis of fungal keratitis requires immediate empirical therapy. Natamycin ophthalmic suspension is the drug of choice for filamentous fungal infection. Fluconazole ophthalmic solution is recommended for Candida infection of the cornea. Amphotericin B eye drops may be required for non-responding cases, but can be quite toxic and requires expert pharmacist for preparation. Other medications have also been tried with moderate success. Consult your eye care professional in any case as they will have the best treatment.
The underlying cause must be treated as soon as possible to stop the disease process. Corticosteroid drop can be used to minimize the scarring on the cornea along with antibiotic cover. However, residual scarring cannot be avoided which can result in long term visual impairment and corneal transplantation is not suitable due to high rejection rate from the corneal vascularization.
Treatments for corneal neovascularization are predominately off-lab with a multitude of complications as a result. The desired results from medical therapy may not always occur, ergo an invasive procedure may be needed to prevent further decrease in corneal avascularity.
For contact lenses related hypoxia, ceasing the use of contact lenses is the first step until corneal neovascularization is addressed by a physician. Modern rigid gas permeable and silicon hydrogel contact lenses have a much higher level of oxygen transmissibility, making them effective alternatives to help prevent corneal neovascularization.
Topical administration of steroids and non-steroid anti-inflammatory drugs are first-line treatment for individuals with CNV. The administration of steroids can increase the risk of infection, glaucoma, cataracts, herpes simplex recurrence. The anti-inflammatory drugs, however, increase the risk of corneal ulceration and melting.
Since VEGF plays an important role in vasculogenesis and pathologic neovascularization associated with eye diseases, a potential treatment for CNV is to inhibit VEGF activity by competing the binding of VEGF with specific neutralizing anti-VEGF antibody. VEGF inhibitors include pegatanib sodium, ranibizumab, and off-label bevacizumab are currently used for treatment of various retinal disease. Anti-VEGF antibodies such as the application of ranibizumab or bevacizumab have has been shown to reduce corneal neovascularization. Both ranibizumab and bevacizumab uses the same mechanism and inhibits all iso-forms of VEGF. The significant reduction in invasion of in-growth blood vessels in terms of neovascular area and vessel caliber suggests that treatment with ranibizumab induces thinning of the blood vessels, however, there's no significant change of the blood vessel's length. Using anti-VEGF antibodies to treat CNV has some limitations such as it is not a cure and may require repeated treatments to maintain positive effects over time. Topical and/or subconjunctival administration of bevaicizumab or ranibizumab have demonstrated short-term safety and efficacy, however long term effects have not been documented. Anti-VEGF therapy is currently an experimental treatment.
If the cornea is inflamed via corneal neovascularization, the suppression of enzymes can block CNV by compromising with corneal structural integrity. Corneal neovascularization can be suppressed with a combination of orally administration of doxycycline and with topical corticosteroid.
Surgical Options
Invasive solutions for corneal neovascularization are reserved when the medical therapies do not provide the desired results.
Invading blood tissues and ablating tissues in the cornea can be obstructed by the use of laser treatments such as Argon and s. Irradiation and/or damages to adjacent tissues caused by the procedure can result in corneal hemorrhage and corneal thinning. Obstruction of the blood vessels can be unsuccessful due to the depth, size, and, high blood flow rate of the vessels. In conjunction, thermal damage from the lasers can trigger inflammatory response which can exaggerate the neovascularization.
An effective treatment is photodynamic therapy, however, this treatment has limited clinical acceptance due to high costs and many potential complications involved that are also related to laser ablation. Complications can include irradiation from previously injected photosensitive dye inducing apoptosis and necrosis of the endothelium and basement membrane.
Diathermy and cautery is a treatment where an electrolysis needle is inserted into the feeder vessels in the limbus. The vessels are obstructed by a coagulating current through the use of unipolar diathermy unit or by thermal cautery.
A punctal plug may be inserted into the tear duct by an optometrist or ophthalmologist, decreasing the removal of natural tears from the affected eye.
The use of contact lenses may help prevent the abrasion during blinking lifting off the surface layer and uses thin lenses that are gas permeable to minimise reduced oxygenation. However they need to be used for between 8–26 weeks and such persistent use both incurs frequent follow-up visits and may increase the risk of infections.
Alternatively, under local anaesthetic, the corneal layer may be gently removed with a fine needle, cauterised (heat or laser) or 'spot welding' attempted (again with lasers). The procedures are not guaranteed to work, and in a minority may exacerbate the problem.
Anterior Stromal Puncture with a 20-25 gauge needle is an effective and simple treatment.
An option for minimally invasive and long-term effective therapy is laser phototherapeutic keratectomy. Laser PTK involves the surgical laser treatment of the cornea to selectively ablate cells on the surface layer of the cornea. It is thought that the natural regrowth of cells in the following days are better able to attach to the basement membrane to prevent recurrence of the condition. Laser PTK has been found to be most effective after epithelial debridement for the partial ablation of Bowman's lamella, which performed prior to PTK in the surgical procedure. This is meant to smoothen out the corneal area that the laser PTK will then treat. In some cases, small-spot PTK, which only treats certain areas of the cornea may also be an acceptable alternative.
People with recalcitrant recurrent corneal erosions often show increased levels of matrix metalloproteinase (MMP) enzymes.
These enzymes dissolve the basement membrane and fibrils of the hemidesmosomes, which can lead to the separation of the epithelial layer. Treatment with oral tetracycline antibiotics (such as doxycycline or oxytetracycline) together with a topical corticosteroid (such as prednisolone), reduce MMP activity and may rapidly resolve and prevent further episodes in cases unresponsive to conventional therapies. Some have now proposed this as the first line therapy after lubricants have failed.
The infection typically takes a long time to heal, since the fungus itself is slow growing. Corneal perforation can occur in patients with untreated or partially treated infectious keratitis and requires surgical intervention in the form of corneal transplantation.
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.
The treatment of corneal perforation depends on the location, severity and the cause of damage
- Tissue adhesive can be used to seal small perforation, but this method cannot be used to treat perforations larger than 1 mm.
- Non infected corneal perforation generally heals when a pressure bandage is used.
- For certain types of corneal perforations, lamellar keratoplasty is used as treatment.
The effect is normally temporary and after a period of six to eight weeks, the cornea usually returns to its former transparency. The recovery can be aided nonsurgically by bandaging with an osmotic saline solution. Non-steroidal anti-inflammatory topical may be used to reduce the pain and inflammation.
Treatment depends on the cause of the keratitis. Infectious keratitis can progress rapidly, and generally requires urgent antibacterial, antifungal, or antiviral therapy to eliminate the pathogen. Antibacterial solutions include levofloxacin, gatifloxacin, moxifloxacin, ofloxacin. It is unclear if steroid eye drops are useful or not.
In addition, contact lens wearers are typically advised to discontinue contact lens wear and replace contaminated contact lenses and contact lens cases. (Contaminated lenses and cases should not be discarded as cultures from these can be used to identify the pathogen).
Aciclovir is the mainstay of treatment for HSV keratitis and steroids should be avoided at all costs in this condition. Application of steroids to a dendritic ulcer caused by HSV will result in rapid and significant worsening of the ulcer to form an 'amoeboid' or 'geographic' ulcer, so named because of the ulcer's map like shape.
Blepharitis is a chronic condition causing frequent exacerbation, thus requires routine eyelid hygiene. Hygienic practices include warm compresses, eyelid massages generating consistent heat at body temperature (98.6 degrees F), and eyelid scrubs. A Cochrane Systematic Review of topical antibiotics was shown to be effective in providing symptomatic relief and clearing bacteria for individuals with anterior blepharitis. Topical steroids provided some symptomatic relief, but they were ineffective in clearing bacteria from the eyelids. Lid hygiene measures such as warm compresses and lid scrubs were found to be effective in providing symptomatic relief for participants with anterior and posterior blepharitis.
Treatment is cause-related, but also symptomatic if the underlying cause is unknown or not correctable. It is also important to note that most ulcers will heal completely without any intervention. Treatment can range from simply smoothing or removing a local cause of trauma, to addressing underlying factors such as dry mouth or substituting a problem medication. Maintaining good oral hygiene and use of an antiseptic mouthwash or spray (e.g. chlorhexidine) can prevent secondary infection and therefore hasten healing. A topical analgesic (e.g. benzydamine mouthwash) may reduce pain. Topical (gels, creams or inhalers) or systemic steroids may be used to reduce inflammation. An antifungal drug may be used to prevent oral candidiasis developing in those who use prolonged steroids. People with mouth ulcers may prefer to avoid hot or spicy foods, which can increase the pain. Self-inflicted ulceration can be difficult to manage, and psychiatric input may be required in some people.
Pentoxifylline is a useful add on treatment to compression stockings and may also help by itself. It works by reducing platelet aggregation and thrombus formation. Gastrointestinal disturbances were reported as a potential adverse effect.
Sulodexide, which reduces the formation of blood clots and reduces inflammation, may improve the healing of venous ulcers when taken in conjunction with proper local wound care. Further research is necessary to determine potential adverse effects, the effectiveness, and the dosing protocol for sulodexide treatment.
An oral dose of aspirin is being investigated as a potential treatment option for people with venous ulcers. A 2016 Cochrane systematic review concluded that further research is necessary before this treatment option can be confirmed to be safe and effective.
Oral zinc supplements have not been proven to be effective in aiding the healing of venous ulcers, however more research is necessary to confirm these results.
Skin ulcers may take a very long time to heal. Treatment is typically to avoid the ulcer getting infected, remove any excess discharge, maintain a moist wound environment, control the edema, and ease pain caused by nerve and tissue damage.
Topical antibiotics are normally used to prevent the ulcer getting infected, and the wound or ulcer is usually kept clear of dead tissue through surgical debridement.
Commonly, as a part of the treatment, patients are advised to change their lifestyle if possible and to change their diet. Improving the circulation is important in treating skin ulcers, and patients are consequently usually recommended to exercise, stop smoking, and lose weight.
In recent years, advances have been made in accelerating healing of chronic wounds and ulcers. Chronic wounds produce fewer growth hormones than necessary for healing tissue, and healing may be accelerated by replacing or stimulating growth factors while controlling the formation of other substances that work against them.
Leg ulcers can be prevented by using compression stockings to prevent blood pooling and back flow. It is likely that a person who has had a skin ulcer will have it again; use of compression stockings every day for at least 5 years after the skin ulcer has healed may help to prevent recurrence.
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.
Non-elastic, ambulatory, below knee (BK) compression counters the impact of reflux on venous pump failure. Compression therapy is used for venous leg ulcers and can decrease blood vessel diameter and pressure, which increases their effectiveness, preventing blood from flowing backwards. Compression is also used to decrease release of inflammatory cytokines, lower the amount of fluid leaking from capillaries and therefore prevent swelling, and prevent clotting by decreasing activation of thrombin and increasing that of plasmin. Compression is applied using elastic bandages or boots specifically designed for the purpose.
Regarding effectiveness, compression dressings improve healing. It is not clear whether non-elastic systems are better than a multilayer elastic system. Patients should wear as much compression as is comfortable. The type of dressing applied beneath the compression does not seem to matter, and hydrocolloid is not better than simple low adherent dressings. Recently there have been clinical studies on a multi-functional botanical-based ointment in combination with compression therapy in the treatment of difficult-to-heal wounds, including venous leg ulcers.
Intermittent pneumatic compression devices may be used, but it is not clear that they are superior to simple compression dressings.
It is not clear if interventions that are aimed to help people adhere to compression therapy are effective. More research is needed in this field.