The effects of physiological changes and environmental factors on tear film and treatment for controlling dry eye - Essay Example

?The effects of physiological changes and environmental factors on the tear film (on the eye) and the various forms of treatment to control dry eye The effects of physiological changes and environmental factors on the tear film (of the eye) and various types of treatment for controlling dry eye 9/15/2011 University ABC Author XYZ Table of content Abstract – page 1 Glossary – page 1 Introduction- page 2 Justification- page 6 Thesis – page 6 Method,- page 6 Findings and Discussion – page 6 Conclusion – page 16 References – page 17 Abstract This article gives an overview of a disease known as dry eyes, the main causes of dry eyes and particular mechanism. The major reason why this problem occurs and how we diagnose such conditions, possible reactions of medicine on a patient. The patient nervousness is discussed as is the change in lifestyle due to this problem. The paper provides an insight into the effects of physiological changes and environmental factors which result in dry eye problem or which have the capacity to enhance this problem. Glossary ATD – aqueous tear deficiency Etiopathogenic – to do with the cause and pathology of a particular condition or disease Interpalpebral – between the eyelids KCS - keratoconjunctivitis sicca, dry eye. MDEQ, McMonnies & Ho Dry Eye Questionnaire None Invasive Tear Break Up Time. A time of less than 10 seconds between blinks is considered to be diagnostic of dry eye. (The Eye Digest (2003) PRK, - photorefractive keratectomy, a form of non invasive refractive surgery Punctal plug - small medical device made of silicone which is inserted into the tear ducts or puncta in order to block. This results in preventing the drainage of liquid from the eye surface, thus retaining moisture on the eye surface. Schrimer Tear Test – special filter paper measures the volume of tear production Sebaceous glands. Glands which produce products from the substance of the gland Sjogren's syndrome. A systematic inflammatory condition which can cause damage to the lacrimal gland. TFBUT- Tear Film Break Up Time Introduction Introduction Dry eye is a disease of the tears. The cause of dry eye involves multiple factors. The optical surface of eye is put to discomfort. The suffering people object that their eye is feeling dry, sore, burning, gritty, scratchy and irritated at the same time. They also complain about their blurred vision. Damage is done to the front surface of eye. Vision is also affected because it is impaired reflexively. The intention of this study is to examine the results of environmental conditions and changes occurring due to physiological factors on ‘dry eye’. It is also known as Chronic Ocular Irritation. Dry eye is also called keratoconjunctivitis sicca. It is also said as keratitis sicca. This is an inflammatory disorder of the tear gland system. It also involves the attack of inflammatory cells inside the lacrimal glands. Meibomian glands are also a part of it. Blinking is an act of an eye used to spread tears on eye surface. In certain conditions dry eye is a result of tear produced in excess. These tears are almost made up of water and cause problem to eye. Tears in eye have many functions. Emotions are expressed, lubrication is provided and unwanted particles are washed, eye’s surface is maintained, and infection is also prevented with the help of tears. Whenever the mechanism of eye stops responding in a proper manner, the reason behind this problem is the imbalanced ratio of tear production from eye and its proper drainage. The outcome of this condition is dry eye. Reduced quantity of tears in eye than the required one, results in dry eye. The sub division of this condition is collagen vascular. Sjogren disease is related to KCS. Non-Sjogren is linked with KCS. This disease is spread all over the world and found in every race of people. The majority of the victims are females. It is the result of inflammatory action which disturbs the vascular system including rheumatoid arthritis, infection including mumps because of the development of nodules. Trauma is second reason behind this. Foster et al ( 2011) state that the cause of a dry eye is decrease of tear production and imbalance in tear fluid. Increase in rate of evaporation is also a reason due to which surface eye suffers from imbalances in ingredients which makes up the tear film. Tears are the actual fluid present in eye. It is produced in the action of cutting onions or due smoke. These are called reflex tears. Dry eye mainly disturbs basic tears. Tears comprise of water as moisture, oil as lubrication, and infection is prevented with the help of antibodies. The meibomian and lacrimal glands work together with the goblet cells, the corneal epithelium and the mechanism of blinking and all of them work together. If any of these stops working perfectly, it will result to dry eye problem. Around 7% of adults over 40 are suffering from this disease. Over 50, the percentage increases up to 20%. The quantity of oil reduces when we grow older. Donnefeld ( 2003) states that this problem is not related with old age factor. The main reason is that lacrimal glands are occupied by inflammatory cells. Step by step treatment is an optimal solution. If the person is at the initial stages of disease and has strong personal history of collagen vascular disease, it is recommended to use artificial tears. The use of anti-histamine drugs also causes this problem. The ratio of low iodine in a person is one of the factors (Gupta, 2007). Tears help us to protect eye, bend light for the vision. Irritation is felt due to dry eye. Blur vision because of absence of moisture makes the eye more sensitive. The tear has three intertwining layers (Foster (2011) The innermost layer This, produced with goblet cells and also by actual eye surface (0.02-0.05 ?m) is hydrophilic. The purpose is to coat the cornea and grant the other layers to adhere to the surface of the cornea. Aqueous layer.(7?m) It helps to move the innermost one. It is made up of fluid of lacrimal gland just below the upper eyelid, with accessory lacrimal glands of Wolfring and Krause. The purpose of this layer is to give moisture, nutrients and oxygen to cornea. The fluid contains 60 diverse proteins as well as electrolytes, which includes anti-bacterial ones also. Epidermal growth factor is also one of function of this layer, needed to maintain normal ocular surface. lipid layer It is the outer most layers and oily one. It is coming from the meibomian glands ( Foster 2011) which are sebaceous glands. This acts as a substance to prevent extreme evaporation and confirms uniform and smooth tears which are spread over the surface of eye. These discharges are affects of vascular, hormonal and neural forces. In normal conditions, excessive tears are shifted from lacrimal canaliculi, then to lacrimal sacs and in the last down to the nasal passages and away. Dry eye can be the result of any problem encountered in this complex system of eye. In some cases the patient will suffer from excessive tears. The excessive amount of tear production is a response from nervous system. Patients have noticed in some situation tears are not produced when they are expected. Tears consist of high percentage of water. Dryness can damage the cornea. Neural reflex arc controls Lacrimal glands. Trigeminal nerves contained have their endings in the lacrimal glands. Justification Many people will concern themselves to their dispensing opticians for complaining of dry eye. To provide appropriate treatment, the essential mechanism must be known. Other possible treatments must be considered. Thesis Dry Eye Syndrome has several causes and that’s why it has diverse methods of treatment. Method Different methods are considered. The estimated finding, implications related to dry eye and implications for dispensing opticians are stated. Consideration is given to definitions and their further classifications, trials on research and clinical methods, and the epidemiology of the condition. This is done with the obedience of Data Protection Act of 1998, saving the confidence as well as working with a professional code of practice. Sources which are selected are relevant to the topic and their interest as well. Findings and Discussion For this study, a lot of relevant material has been studied to find out research conclusions done by various qualified researchers in this field. First of all the researcher has gone through a range of topics and has collected all this information as secondary data by reading through a lot of material. The keywords searched by the researcher included but were not limited to dry eye, physiological and environmental factors affecting dry eye condition, dry eye details, dry eye problem and methods to control dry eye condition. Data base of researcher’s school library and community library were searched. Also, some online library databases were searched. One of the most important criteria in selecting an article for research was the publisher and year of publication. Relevancy to the topic and depth of research also counted. Condition has different reasons and relevance also. Once the condition is identified it is also treated as required. This definition is given in Dry Eye Workshop in 2007. The subcommittee gives another definition having three folds. First is known as etiopathogenic, which is to stress the many different sources of the condition. Second is known as mechanistic, presenting the different causes which act across a common mechanism or pathway. In the end they require to know or define the seriousness of the condition. This makes a change of possible treatment and related management choices. After 12 years, they experienced this factor had to be defined in more proper manner in 1995. The definitions of that time was “ A disorder of the tear film due to tear deficiency or excessive evaporation which causes damage to the interpalpebral ocular surface and is associated with symptoms of ocular discomfort. “ The ‘enhanced’ definition arrived at in 2007 was :- Dry eye is a multifactorial disease of the tears and ocular surface that results in feelings of discomfort , visual disturbance, and tears film instability, with potential damage to the ocular surface. It is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface. This document consists of definitions and explains in 18 pages. The Dry Eye Workshop in ( 2007) highlights the efforts done and progress made for acquiring knowledge about the situation from mid-1990. Different researches were discussed and dry eye is one of them. Recent findings comprise of the fact that skin linked with mucin perform the function of a protective barrier in the eyes. Research done by Leith and Willcox in (1998) expresses the requirement of correct levels of lactoferrin. Lactoferrin is a ring binding protein. It is present in granules of neutrophils. Anti-bacterial function is performed when contact lenses are used. Dry eye is not affected with low lactoferrin levels. Lens can cause irritation in eyes. This situation seems to be complicated one. In this condition they can be reacting with lens. Fluid is used for preventing infection or it can be a mechanical problem. Up to date information is available for dispensing opticians. Journal of American Medicine indicate that in 2001 the majority of clinics diagnosed the problem of dry eye solely after its small symptoms and after using tests like McMonnies Questionnaire. Gothwal et. al. ( 2009) states that even the event of deficient tear production gives an abnormal arrangement of tears and tear film associated with it. Presence of adenoviruses is common in children as compared to adults ( The Nemours Foundation 1995) Latest treatments are developed. In 2006 Wilson and Perry explained the effective course of Cyclosporine completed in six months. Dosage is defined, twice in daily course of 0.05% cyclosporine (Restasis) for the time periods of 6 months, and extended one is up to 6 years. 4% of patients continued with symptom, even after completing a course of 6 months or more. The researchers are unable to discover why some patients had successful treatment and unable to differentiate from others having unsuccessful treatments. They conclude:- In such patients, presumably there is effective elimination of inflammatory processes underlying chronic dry eye disease. Such patients should be monitored for long term because a return of disease may be noted. Donnedfeld ( 2003) stated that in cases when a person is still suffering from collagen vascular conditions the treatment must be continued. Two doses are taken in a week. Donnenfeld ( 2003)also concluded that patients are requesting this form of treatment. He recommends several tests for proper confirmation of diagnosis. These tests include supra-vital staining of the conjunctiva and cornea with the help of an agent such as Lissamine Green. This agent reveals the classic pattern of conjunctival staining in the interpalpebral fissure. Schrimer test is also suggested by Donnenfeld ( 2003). This test estimates exactly the actual amount of tear production happening at the movement. Tear breakup test is also mention by Fujita et al in 2005. A person may be having a short tear film break-up time as a result of a disease due to some systemic medication. It results into ocular dryness. Blinking rate caused after staring at computer screen. Health and Safety Executive in their 2006 document state that no evidence is found that working with VDUs can results into a permanent damage to eyes or sight, but working for a long time period can cause tiredness and irritation. If the person is suffering from definite collagen vascular condition like lupus, Hashimoto's thyroiditis or rheumatoid arthritis then prescription of Cyclosporine is done on immediate basis. He stated that patients suffering from moderate dry eye are encountering the same infiltration of their lacrimal glands by T cells as those with collagen related conditions. In short Cyclosporine is also suggested for such patients. Time period of resolution is within 6 months. If not, other treatments must be tested. Donnenfeld explains the case where it is found that dry eye symptoms are found to be similar to neurotrophic issues. Punctual plugs are eaten before the starting of Cyclosporine therapy. Punctal occlusion can be done on a permanent basis. Methods such as laser ‘welding’ is used or cauterization as well. Both of them are irreversible. Silicone punctual plugs are offered in various sizes to grab individual people. It is also removed at a later stage if its presence results into an excess of tears being made. Other recommended treatments are Restasis (Allergan) which are eye drops. It helps the eye to produce more amounts of tears. ( Lee and Bailey , 2000). In normal circumstances the tear layer film covering the eye is evaporating on constant basis and being refilled. Tears which are produced can find their place in tiny holes. These tiny holes are on the very edge of eyelids. Whenever the blinking function of eye occurs, it results into a new layer of tears which spread across the eye surface. Even if the tears are being formed normally, problems can still find the root of it. Donnenfeld associate dry eye with the menopause and in such cases condition can become worse as time passes, as the levels of circulating androgen hormones are decreased. Miljanovic et al. (2005) have determined a linkage between high diets in Omega 6 fatty acids. Those consuming a diet with intake of Omega 3 fatty acids in higher proportion were related with a reduced risk of dry eye in females. Another female related finding was that Sjogren’s syndrome, which is an auto resistant condition, frequently detected in women as compared to men, which is a result of producing dryness in the mucus membrane. Dryness for the mucus membrane is produced in parts of the body including vagina, the mouth and the eyes.( Northrup, 2001). Northrup had done her research in Quebec. She concluded that 3% of people suffer with symptoms; few of them seek medical care. Ratio of the disorder occurrence is almost 9 women and 1male. She further says that other auto-immune conditions including lupus with the ratio of 30% have Sjogren’s syndrome. She works on immune system of the eyes and proposed that other related mucous membranes in usual circumstances protect the body from allergy, and from infectious diseases. In this case cornea and conjunctiva are protected from harmful effects, the normal tear production is maintained. Production of tears by the lacrimal glands is rich in IgA antibodies. The similar glands make such substances which protect the eyes from a person’s own immune system. When the mechanism stops working properly then involvement, including the use of Cyclosporine is required to correct it. The web site, Dry Eye Syndrome .net explains treatments for dry eye. Suggestions for changing lifestyle are helpful. Eating of nutrition is one of them. It includes avoiding too spicy foods. It also concerns with looking down to computer instead watching up. Patient co.uk 2011 The Eye and the Tear Film Specified references are given ( Donnedfeld 2003), how Cyclosporine is managed , it also includes the time which comes before inserting contact lens. Donnedfeld explain about this treatment. This treatment is higher in cost as compared to artificial tears. It is more effective if different cases are considered. An article written by ACLens advises that lenses created from latest materials, which are oxygen permeable silicone hydro gel, cause less problems, compared to older types of contact lenses. Additional causes of dry eyes can be environmental ones. These are explained by St Luke’s Clinic in 2010. Person living at high altitudes or windy climate or hot one and using air-conditioning and remaining in the smoke of cigarette, can have dry eyes. As these conditions result into unnecessary evaporation of fluid from eyes surface. Same problem is occurring when decrease in tear production is required. Two can work together. It was believed that computer operators need specific guidelines if they want to get rid of negative consequences of long hours of working in front of a monitor. In United Kingdom ‘The Health and Safety Regulations’ came in 1992. The Health and Safety Executive has also created guidelines for working with VDU in 2006. The position of both user and screen also disclosed a previously unnoticed visual problem. (November 2005,) Fujita et al give a report on the relation between dry eye and rheumatoid arthritis activity. This proposed another treatment with Sjorgen Syndrome. Later it was discovered that there was no such correlation among the degree of severity of one condition from other. Researchers declare that there was no statistical relationship. The problem of dry eye was neutral of any rheumatoid motion. Conditions which are associated with dry eye include mechanical problems as well. A failure to close the eye lids totally or easily occur with the growth of Bell’s palsy A fewer meet with Stevens-Johnson syndrome (WebMed 2011) , which is a serious organized condition. It is faced due to an allergic reaction by drugs or due to infective agents. At its most extreme the globe of the eye may be holed. Many drugs have been mentioning (Patient.co.uk, 2010) which contribute to progress the symptoms of dry eye. These include diuretics, antihistamines, some antidepressants; beta-blockers drugs used in cases of depression and excessive anxiety, and in some cases eye drops also used for allergic or infective conjunctivitis ( Kinshuck 2011) may cause difficulties. It is related with diabetes as reported by Kaiserman et al ( 2005). Other researchers including Tumosa ( 2008) state that the seriousness of dry eye symptoms is inferior. It can be a cause of blinking mechanism. This mechanism occurs in condition of a droopy eyelid. This condition appears on an acting basis after laser eye surgery. Dartt ( 2010) explains in a few examples, symptoms may continue for extended period. She concluded that people having low level of tear production before the treatment of LASIX surgery have to suffer from long term difficulties. Lee and Bailey (2000) also referred things as a modern tendency. Surgery on the eye lids is one of them. This causing the inability of closing eyes in a proper manner can lead to dry eye problems. Dartt explains how research has showed that those with a pre-surgical tear production value exceeding 20 mm and causing wetting of the Schirmer strip in 5 minutes period are the conditions indicating dry eye symptoms. Case of dry eye can be more affected if lenses are used. Lee and Bailey ( 2000) explain the case of dry eye is mostly found in people using contact lenses. In recent times Kent ( July 2011) indicates that both LASIX and PRK events are occurring. In early stages, it is considered essential to check the possibility of dry eye harm. A new test, currently under consideration by America’s Food and Drug Administration is made by hum to check dry eye effect. The test is used to discover signs of inflammation with the help of sample. It can be detected by the presence or absence of MMP-9. It is a cytokine which is shaped by epithelial cells that are inflamed and it also provides a reliable marker. It can easily detect an immediate stage of dry eye and ocular surface disease. Kent quotes Professor Kaufman of Louisiana State University Medical School who has said :- Testing has demonstrated a very high correlation between the presence of MMP-9 and dryness, and MMP-9 is not found on normal eyes. The professor is also quoted in the same article that :- In addition, several papers in the literature suggest that the presence or absence of MMP-9 may tell you whether or not a patient will respond to treatment with cyclosporine, doxycycline or steroids. To sum up, all the available treatments for dry eye, result into treatments in countless forms. In some cases it easy to increase the tear production level e.g. Restasis ( Allergen) as described by Lee and Bailey 2000; Eye lid scrubs are utilized in events of meiobomianitis and blepharitis.; use of doxycycline and other for meiobomianitis is a third one ; and the use of prompt occlusion. In early diagnoses various ointments and drops are used. It is given in website that DryEyePain.com (2002) offers treatments which contain materials such as methylcellulose. Some people may be allergic to this and other types may prevent allergic reactions. Course of medicine must be followed according to the treatment. Small pellets are introduced beneath the eye lids, in many cases once in a day. It is designed to reduce evaporation rate of tears if problem is identified as a correct one. Conclusion The above results and theories are useful for opticians. This situation is followed in many cases when control is preferred rather than cure option. The goal is to find out the best therapy and related methods to follow. One single optimum solution for dry eye doesn’t exist. People suffer from the same diseases but go through different conditions. Like excessive flow of tears and insufficient tears when required. In some situation person is not able to produce tear but he is trying to produce it. Like when a person is hurt with knife. In this situation he definitely wants to cry but can’t. The reason behind this the disease of dry eye from which the person is suffering. Different condition of eye and their related impacts are discussed in detail. The use of lenses must be reduced by the person suffering from dry eye. It is not even preferable to use lenses. Different mechanisms are used to treat the disease. In case of wrong treatment, cornea is damaged. The diet supplementary is also used as cure. Life style is changed and rich diets like Omega 6 rich foods are utilized. The St Luke’s Clinic ( 2010) advice for improving hydration problem in eyes is to consume 8 to 10 glasses of water daily. Opticians must know the different treatments in this condition. Treatment must be done step by step. Success is not urgent case in dry eye. Slow and step by step treatment gives relief for long period of time. 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