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Several options exist for the treatment of BRVO. These treatments aim for the two of the most significant complications of BRVO, namely macular edema and neovascularization.
- Systemic treatment with oral Aspirin, subcutaneous Heparin, or intravenous thrombolysis have not been shown to be effective treatments for CRVO and for BRVO no reliable clinical trial has been published.
- Laser treatment of the macular area to reduce macular edema is indicated in patients who have 20/40 or worse vision and did not spontaneously improve for at least 3 months (to permit the maximum spontaneous resolution) after the development of the vein occlusion. It is typically administered with the argon laser and is focused on edematous retina within the arcades drained by the obstructed vein and avoiding the foveal avascular zone. Leaking microvascular abnormalities may be treated directly, but prominent collateral vessels should be avoided.
- The second indication of laser treatment is in case of neovascularization. Retinal photocoagulation is applied to the involved retina to cover the entire involved segment, extending from the arcade out to the periphery. Ischemia alone is not an indication for treatment provided that follow-up could be maintained.
- Preservative-free, nondispersive Triamcinolone acetonide in 1 or 4 mg dosage may be injected into the vitreous to treat macular edema but has complications including elevated intraocular pressure and development of cataract. Triamcinolone injection is shown to have similar effect on visual acuity when compared with standard care (Laser therapy), However, the rates of elevated intraocular pressure and cataract formation is much higher with the triamcinolone injection, especially the higher dosage. Intravitreal injection of Dexamethasone implant (Ozurdex; 700,350 μg) is being studied, its effect may last for 180 days. The injection may be repeated however with less pronounced effect. Although the implant was designed to cause less complications, pressure rise and cataract formation is noted with this treatment too.
- Anti-VEGF drugs such as Bevacizumab (Avastin; 1.25 -2.5 mg in 0.05ml) and Ranibizumab (lucentis) injections are being used and investigated. Intravitreal anti-VEGFs have a low incidence of adverse side effects compared with intravitreal corticosteroids, but are currently short acting requiring frequent injections. Anti-VEGF injection may be used for macular edema or neovascularization. The mechanism of action and duration of anti-VEGF effect on macular edema is currently unknown. The intraocular levels of VEGF are increased in eyes with macular edema secondary to BRVO and the elevated VEGF levels are correlated to the degree and severity of the areas of capillary nonperfusion and macular edema.
- Surgery is employed occasionally for longstanding vitreous hemorrhage and other serious complications such as epiretinal membrane and retinal detachment.
- Arteriovenous sheathotomy has been reported in small, uncontrolled series of patients with BRVO. BRVO typically occurs at arteriovenous crossings, where the artery and vein share a common adventitial sheath. In arteriovenous sheathotomy an incision is made in the adventitial sheath adjacent to the arteriovenous crossing and is extended along the membrane that holds the blood vessels in position to the point where they cross, the overlying artery is then separated from the vein.
Macular edema sometimes occurs for a few days or weeks after cataract surgery, but most such cases can be successfully treated with NSAID or cortisone eye drops. Prophylactic use of Nonsteroidal anti-inflammatory drugs has been reported to reduce the risk of macular edema to some extent.
In 2010 the US FDA approved the use of Lucentis intravitreal injections for macular edema.
Iluvien, a sustained release intravitreal implant developed by Alimera Sciences, has been approved in Austria, Portugal and the U.K. for the treatment of vision impairment associated with chronic diabetic macular edema (DME) considered insufficiently responsive to available therapies. Additional EU country approvals are anticipated.
In 2013 Lucentis by intravitreal injection was approved by the National Institute for Health and Care Excellence in the UK for the treatment of macular edema caused by diabetes and/or retinal vein occlusion.
On July 29, 2014, Eylea (aflibercept), an intravitreal injection produced by Regeneron Pharmaceuticals Inc., was approved to treat DME in the United States.
A 2014 Cochrane Systematic Review studied the effectiveness of two anti-VEGF treatments, ranibizumab and pegaptanib, on patients suffering from macular edema caused by CRVO. Participants on both treatment groups showed a reduction in macular edema symptoms over six months.
Another Cochrane Review examined the effectiveness and safety of two intravitreal steroid treatments, triamcinolone acetonide and dexamethasone, for patients with from CRVO-ME. The results from one trial showed that patients treated with triamcinolone acetonide were significantly more likely to show improvements in visual acuity than those in the control group, though outcome data was missing for a large proportion of the control group. The second trial showed that patients treated with dexamethasone implants did not show improvements in visual acuity, compared to patients in the control group.
Evidence also suggests that intravitreal injections and implantation of steroids inside the eye can result in improved visual outcomes for patients with chronic or refractory diabetic macular edema.
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.
To date, there is no known effective treatment for the non-proliferative form of macular telangiectasia type 2.
Treatment options are limited. No treatment has to date been shown to prevent progression. The variable course of progression of the disease makes it difficult to assess the efficacy of treatments. Retinal laser photocoagulation is not helpful. In fact, laser therapy may actually enhance vessel ectasia and promote intraretinal fibrosis in these individuals. It is hoped that a better understanding of the pathogenesis of the disease may lead to better treatments.
The use of vascular endothelial growth factor (VEGF) inhibitors, which have proven so successful in treating age-related macular degeneration, have not proven to be effective in non-proliferative MacTel type 2. Ranibizumab reduces the vascular leak seen on angiography, although microperimetry suggests that neural atrophy may still proceed in treated eyes.In proliferative stages (neovascularisation), treatment with Anti-VEGF can be helpful.
CNTF is believed to have neuroprotective properties and could thus be able to slow down the progression of MacTel type 2. It has been shown to be safe to use in MacTel patients in a phase 1 safety trial.
Retinal haemorrhages, especially mild ones not associated with chronic disease, will normally resorb without treatment. Laser surgery is a treatment option which uses a laser beam to seal off damaged blood vessels in the retina. Anti-vascular endothelial growth factor (VEGF) drugs like Avastin and Lucentis have also been shown to repair retinal haemorrhaging in diabetic patients and patients with haemorrhages associated with new vessel growth.
The most crucial aspect of managing patients with macular telangiectasia is recognition of the clinical signs. This condition is relatively uncommon: hence, many practitioners may not be familiar with or experienced in diagnosing the disorder. MacTel must be part of the differential in any case of idiopathic paramacular hemorrhage, vasculopathy, macular edema or focal pigment hypertrophy, especially in those patients without a history of retinopathy or contributory systemic disease.
Treatment options for macular telangiectasia type 1 include laser photocoagulation, intra-vitreal injections of steroids, or anti-vascular endothelial growth factor (anti-VEGF) agents. Photocoagulation was recommended by Gass and remains to date the mainstay of treatment. It seems to be successful in causing resolution of exudation and VA improvement or stabilization in selected patients. Photocoagulation should be used sparingly to reduce the chance of producing a symptomatic paracentral scotoma and metamorphopsia. Small burns (100–200 μm) of moderate intensity in a grid-pattern and on multiple occasions, if necessary, are recommended. It is unnecessary to destroy every dilated capillary, and, particularly during the initial session of photocoagulation, those on the edge of the capillary-free zone should be avoided.
Intravitreal injections of triamcinolone acetonide (IVTA) which have proved to be beneficial in the treatment of macular edema by their anti-inflammatory effect, their downregulation of VEGF production, and stabilization of the blood retinal barrier were reported anecdotally in the management of macular telangiectasia type 1. In two case reports, IVTA of 4 mg allowed a transitory reduction of retinal edema, with variable or no increase in VA. As expected with all IVTA injections, the edema recurred within 3–6 months, and no permanent improvement could be shown.14,15 In general, the effect of IVTA is short-lived and complications, mainly increased intraocular pressure and cataract, limit its use.
Indocyanine green angiography-guided laser photocoagulation directed at the leaky microaneurysms and vessels combined with sub-Tenon’s capsule injection of triamcinolone acetonide has also been reported in a limited number of patients with macular telangiectasia type 1 with improvement or stabilization of vision after a mean follow-up of 10 months.16 Further studies are needed to assess the efficacy of this treatment modality.
Recently, intravitreal injections of anti-VEGF agents, namely bevacizumab, a humanized monoclonal antibody targeted against pro-angiogenic, circulatory VEGF, and ranibizumab, a FDA-approved monoclonal antibody fragment that targets all VEGF-A isoforms, have shown improved visual outcome and reduced leakage in macular edema form diabetes and retinal venous occlusions. In one reported patient with macular telangiectasia type 1, a single intravitreal bevacizumab injection resulted in a marked increase in VA from 20/50 to 20/20, with significant and sustained decrease in both leakage on FA and cystoid macular edema on OCT up to 12 months. It is likely that patients with macular telangiectasia type 1 with pronounced macular edema from leaky telangiectasis may benefit functionally and morphologically from intravitreal anti-VEGF injections, but this warrants further studies.
Today, laser photocoagulation remains mostly effective, but the optimal treatment of macular telangiectasia type 1 is questioned, and larger series comparing different treatment modalities seem warranted. The rarity of the disease however, makes it difficult to assess in a controlled randomized manner.
However, these treatment modalities should be considered only in cases of marked and rapid vision loss secondary to macular edema or CNV. Otherwise, a conservative approach is recommended, since many of these patients will stabilize without intervention.
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.
Treatment is based on the cause of the retinopathy and may include laser therapy to the retina. Laser photocoagulation therapy has been the standard treatment for many types of retinopathy. Evidence show that laser therapy is generally safe and improves visual symptoms in sickle cell and diabetic retinopathy. In recent years targeting the pathway controlling vessel growth or angiogenesis has been promising. Vascular endothelial growth factor (VEGF) seems to play a vital role in promoting neovascularization. Using anti-VEGF drugs (antibodies to sequester the growth factor), research have shown significant reduction in the extent of vessel outgrowth. Evidence supports the use of anti-VEGF antibodies, such as bevacizumab or pegaptanib, seems to improve outcomes when used in conjunction with laser therapy to treat retinopathy of prematurity. The evidence is poorer for treatment of diabetic retinopathy. Use of anti-VEGF drugs did not appear to improve outcomes when compared to standard laser therapy for diabetic retinopathy.
Treatment consists of Anti-VEGF drugs like Lucentis or intravitreal steroid implant (Ozurdex) and Pan-Retinal Laser Photocoagulation usually. Underlying conditions also require treatment. Non-Ischemic CRVO has better visual prognosis than Ischemic CRVO.
A systematic review studied the effectiveness of the anti-VEGF drugs ranibizumab and pagatanib sodium for patients suffering from non-ischemic CRVO. Though there was a limited sample size, participants in both treatment groups showed improved visual acuity over 6 month periods, with no safety concerns.
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.
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.
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.
Telemedicine programs are available that allow primary care clinics to take images using specially designed retinal imaging equipment which can then be shared electronically with specialists at other locations for review. In 2009, Community Health Center, Inc. implemented a telemedicine retinal screening program for low-income patients with diabetes as part of those patients annual visits at the Federally Qualified Health Center.
In terms of the treatment of cytomegalovirus retinitis, oral valganciclovir, intravenous ganciclovir, IV foscarnet, and IV cidofovir are all efficient in the treatment of this condition. Also intravitreal injections, an injection of medicine into the vitreous near the retina, of foscarnet in concomitance with oral valganciclovir can be used for treatment as well.
Often individuals with CMV retinitis will need surgery for either retinal detachment or intravitreal instillation of ganciclovir. Retinal detachment occurs in up to 29% of affected eyes, repair being most effective with endolaser and silicone oil endotamponade.Intravitreal ganciclovir implant has the benefit of less systemic toxicity. An adverse effect of this is retinal detachment (and vitreous hemorrhage), also there is no systemic beneficial effect for cytomegalovirus organ disease.
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.
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.
Treatment is based
on the stage of the disease. Stage 1 does not
require treatment and
should be observed. 4
Neovascularization
(stage 2) responds well
to laser ablation or
cryotherapy.2,4 Eyes
with retinal detachments (stages
3 through 5) require surgery, with
earlier stages requiring scleral
buckles and later stages ultimately
needing vitrectomy. 2,4
More recently, the efficacy of
anti-VEGF intravitreal injections
has been studied. In one study,
these injections, as an in adjunct
with laser, helped early stages
achieve stabilization, but further
investigation is needed.6
Currently treatment of ARN consists of antiviral therapy administered orally. Typical antiviral agents used include famciclovir, valganciclovir, and valacyclovir. While on these medications, a patient's kidney function should be watched. Some physician's also may administer the antiviral agents via intravitreal delivery. Though controversial, some physicians administer steroids (prednisone) and antithrombotic therapy (aspirin).
Some commonly admistered antiviral agents are as follows:
- Acyclovir
- Famciclovir
- Valacyclovir
- Gancicilovir
- Valganciclovir
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.
Several treatments have been attempted for CRAS; however, none show definitive improvement in outcomes. The Undersea and Hyperbaric Medical Society lists Central Retinal Artery Occlusion (CRAO) as an approved indication for Hyperbaric Oxygen Therapy. This a treatment for CRAO that is covered by medical insurance in North America. Other treatments include ocular massage, anterior chamber paracentesis, and inhalation therapy of a mixture of 5% carbon dioxide and 95% oxygen.
Quick determination of the cause may lead to urgent measures to save the eye and life of the patient. High clinical suspicion should be kept for painless vision loss in patients with atherosclerosis, deep venous thrombosis, atrial fibrillation, pulmonary thromboembolism or other previous embolic episodes. Those caused by a carotid artery embolism or occlusion have the potential for further stroke by detachment of embolus and migration to an end-artery of the brain. Hence, proper steps to prevent such an eventuality need to be taken.
Retinal arterial occlusion is an ophthalmic emergency, and prompt treatment is essential. Completely anoxic retina in animal models causes irreversible damage in about 90 minutes. Nonspecific methods to increase blood flow and dislodge emboli include digital massage, 500 mg IV acetazolamide and 100 mg IV methylprednisolone (for possible arteritis). Additional measures include paracentesis of aqueous humor to decrease IOP acutely. An ESR should be drawn to detect possible giant cell arteritis. Improvement can be determined by visual acuity, visual field testing, and by ophthalmoscopic examination.
At a later stage, pan-retinal photocoagulation (PRP) with an argon laser appears effective in reducing the neovascular components and their sequelae.
The visual prognosis for ocular ischemic syndrome varies from usually poor to fair, depending on speed and effectiveness of the intervention. However, prompt diagnosis is crucial as the condition may be a presenting sign of serious cerebrovascular and ischemic heart diseases.
In 2009, the Undersea and Hyperbaric Medical Society added "central retinal artery occlusion" to their list of approved indications for hyperbaric oxygen (HBO). When used as an adjunctive therapy, the edema reducing properties of HBO, along with down regulation of inflammatory cytokines may contribute to the improvement in vision. Prevention of vision loss requires that certain conditions be met: the treatment be started before irreversible damage has occurred (over 24 hours), the occlusion must not also occur at the ophthalmic artery, and treatment must continue until the inner layers of the retina are again oxygenated by the retinal arteries.
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.
Treatment of Eales’ disease comprises:
1. Medical treatment:
A course of oral corticosteroids for extended periods is the main stay of treatment
during active inflammation. A course of antitubercular therapy has also been
recommended in selective cases.
2. Laser photocoagulation of the retina is indicated in stage of neovascularizion.
3. Vitreoretinal surgery is required for nonresolving vitreous haemorrhage and tractional retinal detachment.
•If active TB present - treat with ATT
•otherwise manage the vitreous hemorrhage -
Partial h’ge - postural management with propped up position
Total h’ge - Pars Plana Vitrectomy
While there is no prevention for ARN, exposing a patient to antiviral agents in the earlier phases of the outbreak tend to decrease the duration of the active phase of the disease. Taking antiviral agents after the issue is resolved seems to lessen the chance of it spreading to the other eye.