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While nothing currently can be done to stop or reverse the retinal degeneration, there are steps that can be taken to slow the rate of vision loss. UV-blocking sunglasses for outdoors, appropriate dietary intake of fresh fruit and leafy green vegetables, antioxidant vitamin supplements, and regular intake of dietary omega-3 very-long-chain fatty acids are all recommended.
One study found that a dietary supplement of lutein increases macular pigment levels in patients with choroideremia. Over a long period of time, these elevated levels of pigmentation could slow retinal degeneration. Additional interventions that may be needed include surgical correction of retinal detachment and cataracts, low vision services, and counseling to help cope with depression, loss of independence, and anxiety over job loss.
Idebenone is a short-chain benzoquinone that interacts with the mitochondrial electron transport chain to enhance cellular respiration. When used in individuals with LHON, it is believed to allow electrons to bypass the dysfunctional complex I. Successful treatment using idebenone was initially reported in a small number of patients.
Two large-scale studies have demonstrated the benefits of idebenone. The Rescue of Hereditary Optic Disease Outpatient Study (RHODOS) evaluated the effects of idebenone in 85 patients with LHON who had lost vision within the prior five years. In this study, the group taking idebenone 900 mg per day for 24 weeks showed a slight improvement in visual acuity compared to the placebo group, though this difference was not statistically significant. Importantly, however, patients taking idebenone were protected from further vision loss, whereas the placebo group had a steady decline in visual acuity. Further, individuals taking idebenone demonstrated preservation of color vision and persistence of the effects of idebenone 30 months after discontinuing therapy. A retrospective analysis of 103 LHON patients by Carelli et al. builds upon these results. This study highlighted that 44 subjects who were treated with idebenone within one year of onset of vision loss had better outcomes, and, further, that these improvements with idebenone persisted for years.
Idebenone, combined with avoidance of smoke and limitation of alcohol intake, is the preferred standard treatment protocol for patients affected by LHON. Idebenone doses are prescribed to be taken spaced out throughout the day, rather than all at one time. For example, to achieve a dose of 900 mg per day, patients take 300 mg three times daily with meals. Idebenone is fat soluble, and may be taken with a moderate amount of dietary fat in each meal to promote absorption. It is recommended that patients on idebenone also take vitamin C 500 mg daily to keep idebenone in its reduced form, as it is most active in this state.
Gene therapy is currently not a treatment option, however human clinical trials for both choroideremia and Leber's congenital amaurosis (LCA) have produced somewhat promising results.
Clinical trials of gene therapy for patients with LCA began in 2008 at three different sites. In general, these studies found the therapy to be safe, somewhat effective, and promising as a future treatment for similar retinal diseases.
In 2011, the first gene therapy treatment for choroideremia was administered. The surgery was performed by Robert MacLaren, Professor of Ophthalmology at the University of Oxford and leader of the Clinical Ophthalmology Research Group at the Nuffield Laboratory of Ophthalmology (NLO).
In the study, 2 doses of the AAV.REP1 vector were injected subretinally in 12 patients with choroideremia.
There study had 2 objectives:
- to assess the safety and tolerability of the AAV.REP1 vector
- to observe the therapeutic benefit, or slowing of the retinal degeneration, of the gene therapy during the study and at a 24-month post-treatment time point
Despite retinal detachment caused by the injection, the study observed initial improved rod and cone function, warranting further study.
In 2016, researchers were optimistic that the positive results of 32 choroideremia patients treated over four and a half years with gene therapy in four countries could be long-lasting.
There is no treatment for the disorder. A number of studies are looking at gene therapy, exon skipping and CRISPR interference to offer hope for the future. Accurate determination through confirmed diagnosis of the genetic mutation that has occurred also offers potential approaches beyond gene replacement for a specific group, namely in the case of diagnosis of a so-called nonsense mutation, a mutation where a stop codon is produced by the changing of a single base in the DNA sequence. This results in premature termination of protein biosynthesis, resulting in a shortened and either functionless or function-impaired protein. In what is sometimes called "read-through therapy", translational skipping of the stop codon, resulting in a functional protein, can be induced by the introduction of specific substances. However, this approach is only conceivable in the case of narrowly circumscribed mutations, which cause differing diseases.
There is no cure for retinitis pigmentosa, but the efficacy and safety of various prospective treatments are currently being evaluated. The efficiency of various supplements, such as Vitamin A, DHA, and Lutein, in delaying disease progression remains an unresolved, yet prospective treatment option. Clinical trials investigating optic prosthetic devices, gene therapy mechanisms, and retinal sheet transplantations are active areas of study in the partial restoration of vision in retinitis pigmentosa patients.
Studies have demonstrated the delay of rod photoreceptor degeneration by the daily intake of 15000 IU (equivalent to 4.5 mg) of vitamin A palmitate; thus, stalling disease progression in some patients. Recent investigations have shown that proper vitamin A supplementation can postpone blindness by up to 10 years (by reducing the 10% loss pa to 8.3% pa) in some patients in certain stages of the disease.
The Argus retinal prosthesis became the first approved treatment for the disease in February 2011, and is currently available in Germany, France, Italy, and the UK. Interim results on 30 patients long term trials were published in 2012. The Argus II retinal implant has also received market approval in the US. The device may help adults with RP who have lost the ability to perceive shapes and movement to be more mobile and to perform day-to-day activities. In June 2013, twelve hospitals in the US announced they would soon accept consultation for patients with RP in preparation for the launch of Argus II later that year. The Alpha-IMS is a subretinal implant involving the surgical implantation of a small image-recording chip beneath the optic fovea. Measures of visual improvements from Alpha-IMS studies require the demonstration of the device's safety before proceeding with clinical trials and granting market approval.
The goal of gene therapy studies is to virally supplement retinal cells expressing mutant genes associated with the retinitis pigmentosa phenotype with healthy forms of the gene; thus, allowing the repair and proper functioning of retinal photoreceptor cells in response to the instructions associated with the inserted healthy gene. Clinical trials investigating the insertion of the healthy RPE65 gene in retinas expressing the LCA2 retinitis pigmentosa phenotype measured modest improvements in vision; however, the degradation of retinal photoreceptors continued at the disease-related rate. Likely, gene therapy may preserve remaining healthy retinal cells while failing to repair the earlier accumulation of damage in already diseased photoreceptor cells. Response to gene therapy would theoretically benefit young patients exhibiting the shortest progression of photoreceptor decline; thus, correlating to a higher possibility of cell rescue via the healthy inserted gene.
Currently, there is no treatment for the disease. However, ophthalmologists recommend wearing sunglasses and hats outdoors and blue-light blocking glasses when exposed to artificial light sources, such as screens and lights. Tobacco smoke and second-hand smoke should be avoided. Animal studies also show that high doses of vitamin A can be detrimental by building up more lipofuscin toxin. Dietary non-supplemental vitamin A intake may not further the disease progression.
Clinical trials are being conducted with promising early results. The trials may one day lead to treatments that might halt, and possibly even reverse, the effects of Stargardt disease using stem cell therapy, gene therapy, or pharmacotherapy.
The Argus retinal prosthesis, an electronic retinal implant, was successfully fitted to a 67-year-old woman in Italy at the Careggi Hospital in 2016. The patient had a very advanced stage of Stargardt’s disease, and a total absence of peripheral and central visual fields.
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
The progressive nature of and lack of a definitive cure for retinitis pigmentosa contribute to the inevitably discouraging outlook for patients with this disease. While complete blindness is rare, the patient's visual acuity and visual field will continue to decline as initial rod photoreceptor and later cone photoreceptor degradation proceeds. Possible treatments remain in the research and clinical trial stages; however, treatment studies concerning visual restoration in retinitis pigmentosa prove promising for the future.
Studies indicate that children carrying the disease genotype benefit from presymptomatic counseling in order to prepare for the physical and social implications associated with progressive vision loss. While the psychological prognosis can be slightly alleviated with active counseling the physical implications and progression of the disease depend largely on the age of initial symptom manifestation and the rate of photoreceptor degradation, rather than access to prospective treatments. Corrective visual aids and personalized vision therapy provided by Low Vision Specialists may help patients correct slight disturbances in visual acuity and optimize their remaining visual field. Support groups, vision insurance, and lifestyle therapy are additional useful tools for those managing progressive visual decline.
There is no specific treatment to this disorder. However, several symptoms may be alleviated. For instance, anemia is treated by iron supplements. Some of the movement deficiencies may be corrected with orthopedic intervention. The corneal clouding can be, at least, temporarily corrected by corneal transplantation.
"See the equivalent section in the main mucolipidosis article.
A disease that threatens the eyesight and additionally produces a hair anomaly that is apparent to strangers causes harm beyond the physical. It is therefore not surprising that learning the diagnosis is a shock to the patient. This is as true of the affected children as of their parents and relatives. They are confronted with a statement that there are at present no treatment options. They probably have never felt so alone and abandoned in their lives. The question comes to mind, "Why me/my child?" However, there is always hope and especially for affected children, the first priority should be a happy childhood. Too many examinations and doctor appointments take up time and cannot practically solve the problem of a genetic mutation within a few months. It is therefore advisable for parents to treat their child with empathy, but to raise him or her to be independent and self-confident by the teenage years. Openness about the disease and talking with those affected about their experiences, even though its rarity makes it unlikely that others will be personally affected by it, will together assist in managing life.
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.
There is no known cure for this syndrome. Patients usually need ophthalmic surgery and may also need dental surgery
Genetic counseling and screening of the mother's relatives is recommended.
Gene-based therapies for patients with HSAN I are not available to date, hence supportive care is the only treatment available for the patients. Ulcero-mutilating complications are the most serious, prominent, and leading diagnostic features in HSAN I. Since the complications mimic foot ulcers caused by diabetic neuropathy, the treatment for foot ulcers and infections can follow the guidelines given for diabetic foot care which starts with early and accurate counseling of patients about risk factors for developing foot ulcerations. Orthopedic care and the use of well fitting shoes without pressure points should also be included. Recently, the treatment of the foot complications has reached an efficient level allowing treatment on an outpatient basis. Early treatment of the foot complications often avoids hospitalization and, in particular, amputations. In sum, the principles of the treatment are removal of pressure to the ulcers, eradication of infection, and specific protective footwear afterwards.
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.
Laser treatment of drusen has been studied. While it is possible to eliminate drusen with this treatment strategy, it has been shown that this fails to reduce the risk of developing the choroidal neovascularisation which causes the blindness associated with age-related macular degeneration.
Corticosteroids are administered through IV or orally. They cause lymphocytopenia, a condition where white blood cell levels are abnormally low. Corticosteroids cause white blood cell death, lowering their numbers throughout the body. They also cause white blood cells to recirculate away from the area of damage (the retina). This minimizes damage caused by the antibodies produced by the white blood cells. Often, this is treatment is combined with plasmapheresis. Instead of treating the plasma and blood cells, they are replaced with a healthy donor mixture. Patients who respond positively show improved visual fields and an almost complete disappearance of anti-retinal antibodies.
Corneal transplant surgery may be difficult due to the peripheral thinning of the cornea, even with large and off-center grafts. Therefore, surgery is usually reserved for patients that do not tolerate contact lenses. Several different surgical approaches may be taken, and no one approach is currently established as the standard. Examples of surgical procedures used for PMD include: wedge resection, lamellar crescentic resection, penetrating keratoplasty, lamellar keratoplasty, epikeratoplasty and intracorneal segments. Transplantation of the entire thickness of the cornea (penetrating keratoplasty) may be performed if there is enough normal tissue present. However, if there is not enough normal tissue present, then attaching the graft is difficult.
Due to the thinning of the cornea, PMD patients are poor candidates for procedures such as LASIK and photorefractive keratectomy.
Treatment requires careful consideration of angiographic findings when a choroidal neovascular membrane is suspected which is a condition that responds to treatment. A vitreo-retinal specialist (an ophthalmologist specialized in treatment of retinal diseases) should be consulted for proper management of the case.
Presumed ocular histoplasmosis syndrome and age-related macular degeneration (AMD) have been successfully treated with laser, anti-vascular endothelial growth factors and photodynamic therapy. Ophthalmologists are using anti-vascular endothelial growth factors to treat AMD and similar conditions since research indicates that vascular endothelial growth factor (VEGF) is one of the causes for the growth of the abnormal vessels that cause these conditions.
There is evidence suggesting corneal collagen cross-linking may be beneficial for patients with pellucid marginal degeneration. Research shows some promising results by combining collagen cross linking with photorefractive keratectomy, or with topography-guided transepithelial surface ablation.
If patients with HSAN I receive appropriate treatment and counseling, the prognosis is good. Early treatment of foot infections may avoid serious complications. Nevertheless, the complications are manageable, thus allowing an acceptable quality of life. The disease progresses slowly and does not influence the life expectancy if signs and symptoms are properly treated.
No medical or surgical treatment is available for this condition.
It can be treated with laser coagulation, and more commonly with medication that stops and sometimes reverses the growth of blood vessels.
A randomized control trial found that bevacizumab and ranibizumab had similar efficacy, and reported no significant increase in adverse events with bevacizumab. A 2014 Cochrane review found that the systemic safety of bevacizumab and ranibizumab are similar when used to treat neovascular AMD, except for gastrointestinal disorders. Bevacizumab however is not FDA approved for treatment of macular degeneration. A controversy in the UK involved the off-label use of cheaper bevacizumab over the approved, but expensive, ranibizumab. Ranibizumab is a smaller fragment, Fab fragment, of the parent bevacizumab molecule specifically designed for eye injections. Other approved antiangiogenic drugs for the treatment of neo-vascular AMD include pegaptanib and aflibercept.
The American Academy of Ophthalmology practice guidelines do not recommend laser coagulation therapy for macular degeneration, but state that it may be useful in people with new blood vessels in the choroid outside of the fovea who don't respond to drug treatment. There is strong evidence that laser coagulation will result in the disappearance of drusen but does not affect choroidal neovascularisation. A 2007 Cochrane review on found that laser photocoagulation of new blood vessels in the choroid outside of the fovea is effective and economical method, but that the benefits are limited for vessels next to or below the fovea.
Photodynamic therapy has also been used to treat wet AMD. The drug verteporfin is administered intravenously; light of a certain wavelength is then applied to the abnormal blood vessels. This activates the verteporfin destroying the vessels.
Cataract surgery could possibly improve visual outcomes for people with AMD, though there have been concerns of surgery increasing the progression of AMD. A randomized controlled trial found that people who underwent immediate cataract surgery (within 2 weeks) had improved visual acuity and better quality of life outcomes than those who underwent delayed cataract surgery (6 months).
Due to the difficulty of diagnosis, managing this disease is a challenge. For this reason, there is no established treatment for AIR. Clinicians try to reduce and control the autoimmune system attack to prevent any irreversible retinal damage. Methods of treatment include intravenous immunoglobulin (IVIG), plasmapheresis, and corticosteroids.
Without a known family history of LHON the diagnosis usually requires a neuro-ophthalmological evaluation and blood testing for mitochondrial DNA assessment. It is important to exclude other possible causes of vision loss and important associated syndromes such as heart electrical conduction system abnormalities. The prognosis for those affected left untreated is almost always that of continued significant visual loss in both eyes. Regular corrected visual acuity and perimetry checks are advised for follow up of affected individuals. There is beneficial treatment available for some cases of this disease especially for early onset disease. Also, experimental treatment protocols are in progress. Genetic counselling should be offered. Health and lifestyle choices should be reassessed particularly in light of toxic and nutritional theories of gene expression. Vision aides assistance and work rehabilitation should be used to assist in maintaining employment.
For those who are carriers of a LHON mutation, preclinical markers may be used to monitor progress. For example, fundus photography can monitor nerve fiber layer swelling. Optical coherence tomography can be used for more detailed study of retinal nerve fiber layer thickness. Red green color vision testing may detect losses. Contrast sensitivity may be diminished. There could be an abnormal electroretinogram or visual evoked potentials. Neuron-specific enolase and axonal heavy chain neurofilament blood markers may predict conversion to affected status.
Cyanocobalamin (a form of B12) may also be used.
Avoiding optic nerve toxins is generally advised, especially tobacco and alcohol. Certain prescription drugs are known to be a potential risk, so all drugs should be treated with suspicion and checked before use by those at risk. Ethambutol, in particular, has been implicated as triggering visual loss in carriers of LHON. In fact, toxic and nutritional optic neuropathies may have overlaps with LHON in symptoms, mitochondrial mechanisms of disease and management. Of note, when a patient carrying or suffering from LHON or toxic/nutritional optic neuropathy suffers a hypertensive crisis as a possible complication of the disease process, nitroprusside (trade name: Nipride) should not be used due to increased risk of optic nerve ischemia in response to this anti-hypertensive in particular.
Idebenone has been shown in a small placebo controlled trial to have modest benefit in about half of patients. People most likely to respond best were those treated early in onset.
α-Tocotrienol-quinone, a vitamin E metabolite, has had some success in small open label trials in reversing early onset vision loss.
There are various treatment approaches which have had early trials or are proposed, none yet with convincing evidence of usefulness or safety for treatment or prevention including brimonidine, minocycline, curcumin,
glutathione, near infrared light treatment, and viral vector techniques.
"Three person in vitro fertilization" is a proof of concept research technique for preventing mitochondrial disease in developing human fetuses. So far, viable macaque monkeys have been produced. But ethical and knowledge hurdles remain before use of the technique in humans is established.
Treatment modalities currently under clinical investigation include cell therapy, gene therapy and oral therapies.
Regarding cell therapy, Advanced Cell Technology, now called Ocata Therapeutics, has completed Phase I/II multicenter clinical trial using retinal cells derived from human embryonic stem cells (hESCs) to treat patients with Stargardt. After treating and collecting data on 18 patients, Advanced Cell was given approval to test its stem cell therapy on patients with 20/100 vision. In October 2014, the results of the Phase I/II clinical trial were published in "the Lancet".
Research at the preclinical (animal) stage include a new compound that can remove lipofuscin from retinal pigment epithelial cells.