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Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Dry eye is a major symptom that is targeted in the therapy of CVS. The use of over-the-counter artificial-tear solutions can reduce the effects of dry eye in CVS.
Asthenopic symptoms in the eye are responsible for much of the severity in CVS. Proper rest to the eye and its muscles is recommended to relieve the associated eye strain. Various catch-phrases have been used to spread awareness about giving rest to the eyes while working on computers. A routinely recommended approach is to consciously blink the eyes every now and then (this helps replenish the tear film) and to look out the window to a distant object or to the sky—doing so provides rest to the ciliary muscles. One of the catch phrases is the "20 20 20 rule": every 20 mins, focus the eyes on an object 20 feet (6 meters) away for 20 seconds. This basically gives a convenient distance and timeframe for a person to follow the advice from the optometrist and ophthalmologist. Otherwise, the patient is advised to close his/her eyes (which has a similar effect) for 20 seconds, at least every half-hour.
Decreased focusing capability is mitigated by wearing a small plus-powered (+1.00 to +1.50) over-the-counter pair of eyeglasses. Wearing these eyeglasses helps such patients regain their ability to focus on near objects. People who are engaged in other occupations—such as tailors engaged in embroidery—can experience similar symptoms and can be helped by these glasses.
A Pacific University research study of 36 participants found significant differences in irritation or burning of the eyes, tearing, or watery eyes, dry eyes, and tired eyes, that were each improved by filtering lenses versus placebo lenses, but in a follow-up study in 2008, the same team was not able to reproduce the results of the first study.
Competing research has shown blue light-filtering lenses decrease specific aspects of light emissions. Theoretical reductions in phototoxicity were 10.6% to 23.6%. Additionally, melatonin suppression was reduced by 5.8% to 15.0% and scotpic sensitivity by 2.4% to 9.6%. Over 70% of the participants in this testing were unable to detect these changes. The expansion of technology has led to more individuals utilizing computers and televisions which increase the overall exposure to blue light. This has opened up opportunities for companies such as Gunnar Optiks and Razer Inc. to create glasses focused on reducing the exposure to blue light.
Consumption of dark fleshed fish containing dietary omega-3 fatty acids is associated with a decreased incidence of dry eyes syndrome in women. This finding is consistent with postulated biological mechanisms. Early experimental work on omega-3 has shown promising results when used in a topical application or given orally. A randomized, double-masked study published in 2013 to evaluate the effects of a triglyceride of DHA (Omega-3; Brudy Sec 1.5), showed significant results compared to other methods that are being used.
While preventive measures, such as taking breaks from activities that cause eye strain are suggested, there are certain treatments which a person suffering from the condition can take to ease the pain or discomfort that the affliction causes. Perhaps the most effective of these is to remove all light sources from a room and allow the eyes to relax in darkness. Free of needing to focus, the eyes will naturally relax over time, and relieve the discomfort that comes with the strain. Cool compresses also help to some degree, though care should be taken to not use anything cold enough to damage the eyes themselves (such as ice). A number of companies have released "computer glasses" which, through the use of specially tinted lenses, help alleviate many of the factors which cause eye strain, though they do not completely prevent it. Rather, they just make it harder to strain the eye.
Astigmatism may be corrected with eyeglasses, contact lenses, or refractive surgery. Various considerations involving eye health, refractive status, and lifestyle determine whether one option may be better than another. In those with keratoconus, certain contact lenses often enable patients to achieve better visual acuity than eyeglasses. Once only available in a rigid, gas-permeable form, toric lenses are now available also as soft lenses.
Laser eye surgery (LASIK and PRK) is successful in treating astigmatism.
There are many causes of blurred vision:
- Use of atropine or other anticholinergics
- Presbyopia—Difficulty focusing on objects that are close. Common in the elderly. (Accommodation tends to decrease with age.)
- Cataracts—Cloudiness over the eye's lens, causing poor night-time vision, halos around lights, and sensitivity to glare. Daytime vision is eventually affected. Common in the elderly.
- Glaucoma—Increased pressure in the eye, causing poor night vision, blind spots, and loss of vision to either side. A major cause of blindness. Glaucoma can happen gradually or suddenly—if sudden, it is a medical emergency.
- Diabetes—Poorly controlled blood sugar can lead to temporary swelling of the lens of the eye, resulting in blurred vision. While it resolves if blood sugar control is reestablished, it is believed repeated occurrences promote the formation of cataracts (which are not temporary).
- Diabetic retinopathy—This complication of diabetes can lead to bleeding into the retina. Another common cause of blindness.
- Hypervitaminosis A—Excess consumption of vitamin A can cause blurred vision.
- Macular degeneration—Loss of central vision, blurred vision (especially while reading), distorted vision (like seeing wavy lines), and colors appearing faded. The most common cause of blindness in people over age 60.
- Eye infection, inflammation, or injury.
- Sjögren's syndrome, a chronic autoimmune inflammatory disease that destroys moisture producing glands, including lacrimal (tear)
- Floaters—Tiny particles drifting across the eye. Although often brief and harmless, they may be a sign of retinal detachment.
- Retinal detachment—Symptoms include floaters, flashes of light across your visual field, or a sensation of a shade or curtain hanging on one side of your visual field.
- Optic neuritis—Inflammation of the optic nerve from infection or multiple sclerosis. You may have pain when you move your eye or touch it through the eyelid.
- Stroke or transient ischemic attack
- Brain tumor
- Toxocara—A parasitic roundworm that can cause blurred vision
- Bleeding into the eye
- Temporal arteritis—Inflammation of an artery in the brain that supplies blood to the optic nerve.
- Migraine headaches—Spots of light, halos, or zigzag patterns are common symptoms prior to the start of the headache. A retinal migraine is when you have only visual symptoms without a headache.
- Myopia—Blurred vision may be a systemic sign of local anaesthetic toxicity
- Reduced blinking—Lid closure that occurs too infrequently often leads to irregularities of the tear film due to prolonged evaporation, thus resulting in disruptions in visual perception.
- Carbon monoxide poisoning—Reduced oxygen delivery can effect many areas of the body including vision. Other symptoms caused by CO include vertigo, hallucination and sensitivity to light.
A 2009 study, widely reported in the popular press, has suggested that repetitive transcranial magnetic stimulation may temporarily improve contrast sensitivity and spatial resolution in the affected eye of adults with amblyopia. This approach is still under development, and the results await verification by other researchers. It has also been suggested that comparable results can be achieved using different types of brain stimulation such as anodal transcranial direct current stimulation and theta burst rTMS.
A 2013 study concluded that converging evidence indicates decorrelated binocular experience plays a pivotal role in the genesis of amblyopia and the associated residual deficits. Another study of 2013 suggests that playing a version of the popular game Tetris that is modified such that each eye sees separate components of the game may also help to treat this condition in adults. Furthermore, it has been proposed that the effects of this kind of therapy may be further enhanced by noninvasive brain stimulation as shown by a recent study using anodal tDCS.
A 2014 Cochrane review sought to determine the effectiveness of occlusion treatment on patients with sensory deprivation amblyopia, but no trials were found eligible to be included in the review. However, good outcomes from occlusion treatment for sensory deprivation amblyopia likely rely on compliance with the treatment.
The simplest form of treatment for far-sightedness is the use of corrective lenses, eyeglasses or contact lenses. Eyeglasses used to correct far-sightedness have convex lenses.
Topical ciclosporin (topical ciclosporin A, tCSA) 0.05% ophthalmic emulsion is an immunosuppressant. The drug decreases surface inflammation. In a trial involving 1200 people, Restasis increased tear production in 15% of people, compared to 5% with placebo.
It should not be used while wearing contact lenses, during eye infections or in people with a history of herpes virus infections. Side effects include burning sensation (common), redness, discharge, watery eyes, eye pain, foreign body sensation, itching, stinging, and blurred vision. Long term use of ciclosporin at high doses is associated with an increased risk of cancer.
Cheaper generic alternatives are available in some countries.
Although the best outcome is achieved if treatment is started before age 8, children older than age 12 and some adults can show improvement in the affected eye. Children from 9 to 11 who wore an eye patch and performed near-point activities (vision therapy) were four times as likely to show a two-line improvement on a standard 11-line eye chart than children with amblyopia who did not receive treatment. Adolescents aged 13 to 17 showed improvement, as well, albeit to a lesser degree than younger children. Whether such improvements are only temporary, however, is uncertain, particularly if treatment is discontinued.
Tentative evidence shows that perceptual training may be beneficial in adults.
Virtual-reality computer games where each eye receives different signals of the virtual world that the player's brain must combine to successfully play the game have shown some promise in improving both monocularity in the affected eye, as well as binocularity.
There are also surgical treatments for far-sightedness:
- Photorefractive keratectomy (PRK)
- Laser assisted in situ keratomileusis (LASIK)
- Refractive lens exchange (RLE)
- Laser epithelial keratomileusis (LASEK)
Corrective lenses provide a range of vision correction, some as high as +4.0 diopter. Some with presbyopia choose varifocal or bifocal lenses to eliminate the need for a separate pair of reading glasses; specialized preparations of varifocals or bifocals usually require the services of an optometrist. Some newer bifocal or varifocal spectacle lenses attempt to correct both near and far vision with the same lens.
Contact lenses can also be used to correct the focusing loss that comes along with presbyopia. Multifocal contact lenses can be used to correct vision for both the near and the far. Some people choose contact lenses to correct one eye for near and one eye for far with a method called monovision.
New surgical procedures may also provide solutions for those who do not want to wear glasses or contacts, including the implantation of accommodative intraocular lenses. INTRACOR has now been approved in Europe for treatment of both eyes (turning both corneas into multifocal lenses and so dispensing with the need for reading glasses).
Another treatment option for the correction of presbyopia in patients with emmetropia, as well as in patients with myopia, hyperopia and astigmatism is laser blended vision. This procedure uses laser refractive surgery to correct the dominant eye mainly for distance vision and the nondominant eye mainly for near vision, while the depth of field (i.e. the range of distances at which the image is in focus) of each eye is increased. As a result of the increased depth of field, the brain merges the two images, creating a blend zone, i.e. a zone which is in focus for both eyes. This allows the patient to see near, intermediate and far without glasses. Some literature also suggests the benefits achieved include the brain learning to adapt, assimilating two images, one of which is out of focus. Over time, many patients report they are unaware one eye is out of focus.
Surgically implanted corneal inlays are another treatment option for presbyopia. Corneal inlays typically are implanted in the nondominant eye to minimize impact to binocular uncorrected distance vision. They seek to improve near vision in one of three ways: changing the central refractive index, increasing the depth of focus through the use of a pinhole, and reshaping the central cornea.
Sometimes asthenopia can be due to specific visual problems—for example, uncorrected refraction errors or binocular vision problems such as accommodative insufficiency or heterophoria. It is often caused by the viewing of monitors such as those of computers or phones for prolonged periods of time.
According to an American study nearly three in 10 children (28.4%) between the ages of five and 17 have astigmatism. A recent Brazilian study found that 34% of the students in one city were astigmatic. Regarding the prevalence in adults, a recent study in Bangladesh found that nearly 1 in 3 (32.4%) of those over the age of 30 had astigmatism.
A Polish study published in 2005 revealed "with-the-rule astigmatism" may lead to the onset of myopia.
A number of studies have found the prevalence of astigmatism increases with age.
Computer vision syndrome (CVS) is a condition resulting from focusing the eyes on a computer or other display device for protracted, uninterrupted periods of time. Some symptoms of CVS include headaches, blurred vision, neck pain, fatigue, eye strain, dry eyes, irritated eyes, double vision, vertigo/dizziness, polyopia, and difficulty refocusing the eyes. These symptoms can be further aggravated by improper lighting conditions (i.e. glare or bright overhead lighting) or air moving past the eyes (e.g. overhead vents, direct air from a fan).
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.
Convergence insufficiency may be treated with convergence exercises prescribed by an eyecare specialist trained in orthoptics or binocular vision anomalies. Some cases of convergence insufficiency are successfully managed by prescription of eyeglasses, sometimes with therapeutic prisms.
Pencil push-ups therapy is performed at home. Patient brings a pencil slowly to within 2–3 cm of the eye just above the nose about 15 minutes per day 5 times per week. Patients should record the closest distance that they could maintain fusion (keep the pencil from going double as long as possible) after each 5 minutes of therapy. Computer software may be used at home or in an orthoptists/vision therapists office to treat convergence insufficiency. A weekly 60-minute in-office therapy visit may be prescribed. This is generally accompanied with additional in home therapy.
In 2005, the Convergence Insufficiency Treatment Trial (CITT) published two randomized clinical studies. The first, published in Archives of Ophthalmology demonstrated that computer exercises when combined with office based vision therapy/orthoptics were more effective than "pencil pushups" or computer exercises alone for convergency insufficiency in 9- to 18-year-old children. The second found similar results for adults 19 to 30 years of age. In a bibliographic review of 2010, the CITT confirmed their view that office-based accommodative/vergence therapy is the most effective treatment of convergence insufficiency, and that substituting it in entirety or in part with other eye training approaches such as home-based therapy may offer advantages in cost but not in outcome. A later study of 2012 confirmed that orthoptic exercises led to longstanding improvements of the asthenopic symptoms of convergence sufficiency both in adults and in children. A 2011 Cochrane Review reaffirmed that office-based therapy is more effective than home-based therapy, though the evidence of effectiveness is a lot stronger for children than for the adult population.
Both positive fusional vergence (PFV) and negative fusional vergence (NFV) can be trained, and vergence training should normally include both.
Surgical correction options are also available, but the decision to proceed with surgery should be made with caution as convergence insufficiency generally does not improve with surgery. Bilateral medial rectus resection is the preferred type of surgery. However, the patient should be warned about the possibility of uncrossed diplopia at distance fixation after surgery. This typically resolves within 1–3 months postoperatively. The exophoria at near often recurs after several years, although most patients remain asymptomatic.
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.
Distorted vision is a symptom with several different possible causes.
Distortion of vision refers to straight lines not appearing straight, but instead bent, crooked, or wavy. Usually this is caused by distortion of the retina itself. This distortion can herald a loss of vision in macular degeneration, so anyone with distorted vision should seek medical attention by an ophthalmologist promptly. Other conditions leading to swelling of the retina can cause this distortion, such as macular edema and central serous chorioretinopathy.
An Amsler grid can be supplied by an ophthalmologist so that the vision can be monitored for distortion in people who may be predisposed to this problem.
Tunnel vision implies that the peripheral vision, or side vision, is lost, while the central vision remains. Thus, the vision is like looking through a tunnel, or through a paper towel roll. Some disorders that can cause this include:
Glaucoma - severe glaucoma can result in loss of nearly all of the peripheral vision, with a small island of central vision remaining. Sometimes even this island of vision can be lost as well.
Retinitis pigmentosa - This is usually a hereditary disorder which can be part of numerous syndromes. It is more common in males. The peripheral retina develops pigmentary deposits, and the peripheral vision gradually becomes worse and worse. The central vision can be affected eventually as well. People with this problem may have trouble getting around in the dark. Cataract can be a complication as well. There is no known treatment for this disorder, and supplements of Vitamin A have not been proven to help.
Punctate Inner Choroidopathy - This condition is where vessels gro (( material is missing ))
Stroke - a stroke involving both sides of the visual part of the brain may wipe out nearly all of the peripheral vision. Fortunately, this is a very rare occurrence
A meta-analysis found evidence that does not support the use of patching.
Convergence insufficiency or convergence disorder is a sensory and neuromuscular anomaly of the binocular vision system, characterized by a reduced ability of the eyes to turn towards each other, or sustain convergence.
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.
Most eyes with CSR undergo spontaneous resorption of subretinal fluid within 3–4 months, recovery of visual acuity usually follows. Any ongoing corticosteroid treatment should be tapered and stopped, where possible. It is important to check current medication, including nasal sprays and creams, for ingredients of corticosteroids, if found seek advice from a medical practitioner for an alternative.
Treatment should be considered if resorption does not occur within 3–4 months, spontaneously or as the result of counselling.
Careful eye examination by an ophthalmologist or optometrist is critical for diagnosing symptomatic VMA. Imaging technologies such as optical coherence tomography (OCT) have significantly improved the accuracy of diagnosing symptomatic VMA.
A new FDA approved drug was released on the market late 2013. Jetrea (Brand name) or Ocriplasmin (Generic name) is the first drug of its kind used to treat vitreomacular adhension.
Mechanism of Action: Ocriplasmin is a truncated human plasmin with proteolytic activity against protein components of the vitreous body and vitreretinal interface. It dissolves the protein matrix responsible for the vitreomacular adhesion.
Adverse drug reactions: Decreased vision, potential for lens sublaxation, dyschromatopsia (yellow vision), eye pain, floaters, blurred vision.
New Drug comparison Rating gave Jetea a 5 indicating an important advance.
Previously, no recommended treatment was available for the patient with mild symptomatic VMA. In symptomatic VMA patients with more significant vision loss, the standard of care is pars plana vitrectomy (PPV), which involves surgically removing the vitreous from the eye, thereby surgically releasing the symptomatic VMA. In other words, vitrectomy induces PVD to release the traction/adhesion on the retina. An estimated 850,000 vitrectomy procedures are performed globally on an annual basis with 250,000 in the United States alone.
A standard PPV procedure can lead to serious complications including small-gauge PPV. Complications can include retinal detachment, retinal tears, endophthalmitis, and postoperative cataract formation. Additionally, PPV may result in incomplete separation, and it may potentially leave a nidus for vasoactive and vasoproliferative substances, or it may induce development of fibrovascular membranes. As with any invasive surgical procedure, PPV introduces trauma to the vitreous and surrounding tissue.
There are data showing that nonsurgical induction of PVD using ocriplasmin (a recombinant protease with activity against fibronectin and laminin) can offer the benefits of successful PVD while eliminating the risks associated with a surgical procedure, i.e. vitrectomy. Pharmacologic vitreolysis is an improvement over invasive surgery as it induces complete separation, creates a more physiologic state of the vitreomacular interface, prevents the development of fibrovascular membranes, is less traumatic to the vitreous, and is potentially prophylactic. As of 2012, ThromboGenics is still developing the ocriplasmin biological agent. Ocriplasmin is approved recently under the name Jetrea for use in the United States by the FDA.view.
An experimental test of injections of perfluoropropane (CF) on 15 symptomatic eyes of 14 patients showed that vitreomacular traction resolved in 6 eyes within 1 month and resolved in 3 more eyes within 6 months.