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Intraocular pressure can be lowered with medication, usually eye drops. Several classes of medications are used to treat glaucoma, with several medications in each class.
Each of these medicines may have local and systemic side effects. Adherence to medication protocol can be confusing and expensive; if side effects occur, the patient must be willing either to tolerate them or to communicate with the treating physician to improve the drug regimen. Initially, glaucoma drops may reasonably be started in either one or in both eyes. Wiping the eye with an absorbent pad after the administration of eye drops may result in fewer adverse effects, like the growth of eyelashes and hyperpigmentation in the eyelid.
Poor compliance with medications and follow-up visits is a major reason for vision loss in glaucoma patients. A 2003 study of patients in an HMO found half failed to fill their prescriptions the first time, and one-fourth failed to refill their prescriptions a second time. Patient education and communication must be ongoing to sustain successful treatment plans for this lifelong disease with no early symptoms.
The possible neuroprotective effects of various topical and systemic medications are also being investigated.
- Prostaglandin analogs, such as latanoprost, bimatoprost and travoprost, increase uveoscleral outflow of aqueous humor. Bimatoprost also increases trabecular outflow.
- Topical beta-adrenergic receptor antagonists, such as timolol, levobunolol, and betaxolol, decrease aqueous humor production by the epithelium of the ciliary body.
- Alpha2-adrenergic agonists, such as brimonidine and apraclonidine, work by a dual mechanism, decreasing aqueous humor production and increasing uveoscleral outflow.
- Less-selective alpha agonists, such as epinephrine, decrease aqueous humor production through vasoconstriction of ciliary body blood vessels, useful only in open-angle glaucoma. Epinephrine's mydriatic effect, however, renders it unsuitable for closed-angle glaucoma due to further narrowing of the uveoscleral outflow (i.e. further closure of trabecular meshwork, which is responsible for absorption of aqueous humor).
- Miotic agents (parasympathomimetics), such as pilocarpine, work by contraction of the ciliary muscle, opening the trabecular meshwork and allowing increased outflow of the aqueous humour. Echothiophate, an acetylcholinesterase inhibitor, is used in chronic glaucoma.
- Carbonic anhydrase inhibitors, such as dorzolamide, brinzolamide, and acetazolamide, lower secretion of aqueous humor by inhibiting carbonic anhydrase in the ciliary body.
The modern goals of glaucoma management are to avoid glaucomatous damage and nerve damage, and preserve visual field and total quality of life for patients, with minimal side effects. This requires appropriate diagnostic techniques and follow-up examinations, and judicious selection of treatments for the individual patient. Although intraocular pressure is only one of the major risk factors for glaucoma, lowering it via various pharmaceuticals and/or surgical techniques is currently the mainstay of glaucoma treatment.
Vascular flow and neurodegenerative theories of glaucomatous optic neuropathy have prompted studies on various neuroprotective therapeutic strategies, including nutritional compounds, some of which may be regarded by clinicians as safe for use now, while others are on trial.
Ocular hypertension is treated with either medications or laser. Medications that lower intraocular pressure work by decreasing aqueous humor production and/or increasing aqueous humor outflow. Laser trabeculoplasty works by increasing outflow. The cannabinoids found in cannabis sativa and indica (marijuana) have been shown to reduce intraocular pressure, by up to 50% for approximately four to five hours. But due to the duration of effect, significant side-effect profile, and lack of research proving efficacy, the American Glaucoma Society issued a position statement in 2009 regarding the use of marijuana as a treatment for glaucoma.
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.
The best treatment for light sensitivity is to address the underlying cause. Once the triggering factor is treated, photophobia disappears in many but not all cases.
People with photophobia will avert their eyes from direct light, such as sunlight and room lights. They may seek the shelter of a dark room. They may wear sunglasses designed to filter peripheral light and wide-brimmed sun hats.
Wearing sunglasses indoors can make symptoms worse over time as it will dark-adapt the retina which aggravates sensitivity to light. Indoor photophobia symptoms may be relieved with the use of precision tinted lenses which block the green-to-blue end of the light spectrum without blurring or impeding vision.
A paper by Stringham and Hammond, published in the "Journal of Food Science", reviews studies of effects of consuming Lutein and Zeaxanthin on visual performance, and notes a decrease in sensitivity to glare.
The preferred treatment of congenital glaucoma is surgical not medical. The initial procedures of choice are goniotomy or trabeculotomy if the cornea is clear, and trabeculectomy ab externo if the cornea is hazy. The success rates are similar for both procedures in patients with clear corneas. Trabeculectomy and shunt procedures should be reserved for those cases in which goniotomy or trabeculotomy has failed. Cyclophotocoagulation is necessary in some intractable cases but should be avoided whenever possible because of its potential adverse
effects on the lens and the retina.
Untreated glaucoma leads to total blindness. Surgical treatment is required. Presently-utilized surgical procedures include goniotomy, trabeculotomy, or trabeculectomy.
The World Health Organization estimates that 80% of visual loss is either preventable or curable with treatment. This includes cataracts, onchocerciasis, trachoma, glaucoma, diabetic retinopathy, uncorrected refractive errors, and some cases of childhood blindness. The Center for Disease Control and Prevention estimates that half of blindness in the United States is preventable.
If caught early, the neovascularization can be reversed with prompt pan retinal photocoagulation (PRP), or injection of anti-VEGF medications with subsequent PRP. The injection blocks the direct effect of VEGF and acts more quickly but will wear off in about 6 weeks. PRP has a slower onset of action but can last permanently. Once the neovascularization has been longstanding, the new vessels recruit fibrous tissue, and as this forms and contracts, the angle can be permanently damaged, and will not respond to treatment. If this occurs, then surgical intervention is required to reduce the pressure (such as a glaucoma drainage implant)
Most patients can be treated non-surgically with eyeglasses, or contact lenses.
Aside from medical help, various sources provide information, rehabilitation, education, and work and social integration.
If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate." However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.
The early stages of pellucid marginal degeneration may also be managed with soft contact lenses. Success has been shown with the use of rigid gas permeable contact lenses combined with over-refraction. Patients wearing contacts dont report increased problems with glare and contrast sensitivity, but it is not clear if this is due to the corneal disease, or the contact lenses themselves.
New studies found that the use of Scleral contact lens, a type of rigid gas permeable (RGP) lens, may be a good option for most patients with PMD. Most of these lenses are in the range of 15.5mm to 18.0mm in diameter. Regardless of the lens size, it is thought that the larger the RGP lens will in most cases be more comfortable then standard rigid corneal lenses, and at times more comfortable than soft lenses, regardless of the fact that it is a rigid lens. The highlight to the scleral design and the correction of eye disorders such as pellucid marginal degeneration is that vision with these types of lenses is exceptional when fit correctly.
Photophobia may also affect patients' socioeconomic status by limiting their career choices, since many workplaces require bright lights for safety or to accommodate the work being done. Sufferers may be shut out of a wide range of both skilled and unskilled jobs, such as in warehouses, offices, workshops, classrooms, supermarkets and storage spaces. Some photophobes are only able to work night shifts, which reduces their prospects for finding work.
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.
There are good results from multiple doses of intravitreal injections of anti-VEGF drugs such as bevacizumab. A 2017 systematic review update found moderate evidence that aflibercept may have advantages in improving visual outcomes over bevacizumab and ranibizumab, after one year. Present recommended treatment for diabetic macular edema is Modified Grid laser photocoagulation combined with multiple injections of anti-VEGF drugs.
Mydriatic/cycloplegic agents, such as topical homatropine, which is similar in action to atropine, are useful in breaking and preventing the formation of posterior synechia by keeping the iris dilated and away from the crystalline lens. Dilation of the pupil in an eye with the synechia can cause the pupil to take an irregular, non-circular shape (Dyscoria) as shown in the photograph. If the pupil can be fully dilated during the treatment of iritis, the prognosis for recovery from synechia is good. This is a treatable status.
To subdue the inflammation, use topical corticosteroids. If the intra-ocular pressure is elevated then use a PGA such as Travatan Z.
Triamcinolone is a long acting steroid preparation. When injected in the vitreous cavity, it decreases the macular edema (thickening of the retina at the macula) caused due to diabetic maculopathy, and results in an increase in visual acuity. The effect of triamcinolone is transient, lasting up to three months, which necessitates repeated injections for maintaining the beneficial effect. Best results of intravitreal Triamcinolone have been found in eyes that have already undergone cataract surgery. Complications of intravitreal injection of triamcinolone include cataract, steroid-induced glaucoma and endophthalmitis. A systematic review found evidence that eyes treated with the intravitreal injection of triamcinolone had better visual acuity outcomes compared to eyes treated with macular laser grid photocoagulation, or sham injections.
Without treatment, NTG leads to progressive visual field loss and in the last consequence to blindness. The mainstay of conventional glaucoma therapy, reducing IOP by pressure-lowering eye drops or by surgery, is applied in cases of NTG as well. The rationale: the lower the IOP, the less the risk of ganglion cell loss and thus in the long run of visual function. The appearance of disc hemorrhages is always a warning sign that therapeutic approaches are not successful - the small bleedings, usually described as flame-shaped, almost always indicate a progression of the disease.
Besides this classical glaucoma therapy, the vascular component that exists in the majority of NTG patients has to be managed as well. Dips in blood pressure or a generally low blood pressure have to be prevented - which is a rather uncommon approach in modern medicine where high blood pressure is always seen as an immense clinical challenge, affecting large segments of the population. In patients with systemic hypertension under therapy, the blood pressure should not be lowered too rigorously. NTG might be the only severe (= sight-threatening) disease caused in numerous cases by a too low blood pressure. Both magnesium and low dose calcium channel blockers have been employed in the treatment of some NTG patients. There are therapeutic approaches to underlying conditions like Flammer syndrome. A change in nutrition like the intake of sodium-rich foods has been tried as has the oral administration of low-dosed steroids. Lifestyle interventions are recommended in patients with Flammer syndrome like avoidance of fasting and certain stimuli like a cold environment and stress.
Penetrating karatoplasty and endothelial keratoplasty can be used as treatments for severe cases of ICE [2,8]. Because glaucoma and elevated intraocular pressure are often present in ICE patients, long term follow up may be needed to ensure adequate intraocular pressures are maintained [2,7]
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.
For the allergic type, cool water poured over the face with the head inclined downward constricts capillaries, and artificial tears sometimes relieve discomfort in mild cases. In more severe cases, nonsteroidal anti-inflammatory medications and antihistamines may be prescribed. Persistent allergic conjunctivitis may also require topical steroid drops.
Viral conjunctivitis usually resolves on its own and does not require any specific treatment. Antihistamines (e.g., diphenhydramine) or mast cell stabilizers (e.g., cromolyn) may be used to help with the symptoms. Povidone iodine has been suggested as a treatment, but as of 2008 evidence to support it was poor.
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.
With posterior lens luxation, the lens falls back into the vitreous humour and lies on the floor of the eye. This type causes fewer problems than anterior lens luxation, although glaucoma or ocular inflammation may occur. Surgery is used to treat dogs with significant symptoms. Removal of the lens before it moves to the anterior chamber may prevent secondary glaucoma.