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History of Theratears In 1976, Dr. Gilbard began his research with the goal of developing an effective solution for dry eye patients.
The TheraTears formula was developed based on 18 years of research in the clinics and laboratories of the Schepens Eye Research Institute. Useful Links Theratears product information
Chronic Eye Irritation Increased Tear Film Osmolarity
Physiological Changes in Dry Eye Decreased Goblet Cell
Density: Decreased Corneal
Glycogen: For Soothing Relief And Comfort That Works! Preservative Free. Hypotonic. Patented Tear-Matched Electrolyte Balance.
Over the past twenty-five years, slow but steady progress has been made in understanding the causes of contact lens induced dryness, burning and irritation that an increasing number of contact patients report after many years of wearing their lenses successfully. It is now recognised that these symptoms may result from decreased tear secretion due to decreased corneal sensitivity. Rigid lenses decrease corneal sensation more than soft lenses. Other causes may be linked to meibomian gland dysfunction, changes in the environment or other causes which increase tear film evaporation during wear. All of these factors have the potential to increase tear film osmolarity resulting in an osmotic dehydration of the contact lens thus increasing discomfort and decreasing wearing time. Additional irritation may be linked to preservative-induced toxicity from contact lens solution. Sequence Leading to Discomfort Contact lens discomfort worsens through a sequence of events which may more frequently occur with increased contact lens wear. With the onset of dryness, an increase in tear osmolarity pulls water from the surface of the lens. Eventually the tear film loses some of its ability to stick to its surface. The result is the rapid formation of dry spots on the areas of the lens where the tear film cannot hold becomes unstable and ruptures. Management Goals With the large variety of preserved wetting solutions, and comfort drops on the market today, it is understandable why a level of frustration exists over how to address and improve lens wearing comfort. In order to simplify the selection process, a definition of treatment goals is as followed: First, the product recommended must lower tear film osmolarity. The product must not only wet the lens, but must rehydrate it as well. Second and perhaps most importantly, the product must be compatible with the natural electrolyte balance of the human tear film and provide sufficient lubrication to provide long term comfort. Why TheraTears Works Preservative-free TheraTears, was developed as a result of 18 years of research in the clinics and laboratories of Harvard’s Schepens Eye Research Institute. This unique formula provides soothing lubrication of contact lens in case of dryness, burning and irritation. TheraTears has the advantage of being hypnotic so it can fully flip the osmotic gradient, and rehydrate the dehydrated lens surface. In addition TheraTears contains a patented electrolyte balance that accurately matches those found in the human tear film so it not only eliminates preservative-induced toxicity but also protects against electrolyte imbalance toxicity as well. The TheraTears unit-dose delivery system provides patients with relief that is convenient to use. TheraTears Lubricant Eye Drops and TheraTears Liquid Gel contain sodium carboxymethylcellulose. TheraTears is optimally formulated to provide longer-lasting lubrication while reducing blurring and crusting associated with other products. By recommending that patients apply TheraTears to the internal an external surface of the contact lens before insertion, irritation-inducing residue is removed from the lens and the integrity of the tear film’s electrolyte balance is maintained. As a result, contact lenses are much more comfortable on insertion. During contact lens wear, patients should be instructed to instill the contents of one unit dose in both eyes over a five to ten minute period. This will ensure a proper coating of the surface of the eye and lens providing immediate, soothing and long-lasting relief. By adding TheraTears Lubricant Eye Drops as part of your contact lens wearing regimen, or TheraTears Liquid Gel for patients wearing GP or overnight wear lenses, they will feel the difference in lens wearing comfort and long-term success. TheraTears is packaged in a special foil pouch to ensure that it stays as fresh as natural tears. Please see our main website for further details:- The term dry eye covers a variety of conditions with similar symptoms (sore, gritty, burning sensation) and signs (alterations to the tear film and ocular surface). The National Eye Institute workshop defined "dry eye" as "a disorder of the pre-corneal tear film due to tear deficiency or excessive tear evaporation of tears causing damage to the interpalpebral ocular surface associated with ocular discomfort" (Lemp, 1995). Classically this is further sub-divided into tear deficiency and excess tear evaporation subtypes. These were further sub-divided by Lemp in 1995, and the following graphical representation comes from Patel & Blades 2003 text, The Dry Eye, a practical approach. Aqueous deficiency dry eye is most commonly seen in adults, in particular post-menopausal females. It is mainly caused by lacrimal gland destruction or blockage of lacrimal gland ducts. Aqueous deficiency dry eye includes both Sjögrens syndrome and non- Sjögrens syndrome dry eye conditions. Sjögrens syndrome is an autoimmune condition affecting both the salivary and lacrimal glands. Primary Sjögrens syndrome denotes dryness of the mouth and eyes; secondary Sjögrens syndrome is when there is also an association with related connective tissue disease such as rheumatoid arthritis. In primary Sjögrens syndrome there is a focal infiltration of the lacrimal and salivary glands by mononuclear lymphocytes, which destroy the glands and they are replaced by fibrous tissue. For
a diagnosis of Sjögrens syndrome to be made, the patient must
be positive for at least one of these following tests: - HLA-DR3, -DRW52 and -DRW3 are associated with primary Sjögrens syndrome, and HLA-DR4 and -DRW3 are associated with secondary Sjögrens syndrome. The problem is to distinguish between true Sjögrens syndrome patients and those with simple age-related aqueous deficiency dry-eye, so that additional treatments specific to Sjögrens syndrome can be initiated, (e.g. Topical and systemic steroids, NSAIDS, Muscarinic M3 agonists, such as pilocarpine, interferon, methotrexate, azeothiaprine and in severe cases cyclophosphamide). In
secondary Sjögrens syndrome the blood vessels and connective
tissue are also affected by lymphocytic infiltration. This results
in chronic inflammation, which causes in destruction and deformation
of these organs. Sjögrens syndrome patients also have a 40 times risk of developing Non-Hodgkins lymphoma of the salivary glands when compared with normal subjects. Generally, primary Sjögrens syndrome shows more severe ocular involvement than the secondary type. Non- Sjögrens syndrome tear deficient dry eye can be due to either primary or secondary lacrimal disease, lacrimal obstructive disease and reflex causes, such as decreased corneal sensation as after LASIK refractive surgery. Tear secretion may also be decreased by any condition that decreases corneal sensation, e.g. diabetes & herpes zoster, long term contact lens wear and any corneal surgery that involves incisions or ablation of corneal nerves (Gilbard 2004). Evaporative dry eye is most commonly caused by meibomian gland anomalies, which can be blepharitis associated or obstructive meibomian gland dysfunction/disease. To a certain extent MSD is a normal finding in many people with advancing age. It can also be caused by blink disorders, disorders of palpebral aperture (e.g. thyroid eye disease), eyelid/eyeball alignment (e.g. floppy eyelid syndrome) and other causes such as environment (Khurana AK et al, 1991), contact lens wear, drugs (e.g. BAK toxicity in eye drops or topical B-blockers causing epithelial cell metaplasia and loss of goblet cells (ref Shah & Laiquzzaman, Albietz JM, 2001)), and allergy (ref Bron, 2001). In dry eye disorders the corneal and conjunctival epithelial surfaces, and/or the intra-cellular junctions are damaged, altered or compromised (Korb, 2002). The use of stains allows us to view these changes directly and immediately. It is thus extremely important to be able to assess this damage if the diagnosis is to be made and any treatment evaluated for effectivity. Although several techniques have evolved to assess the extent of this damage, ocular surface staining with dyes such as fluorescien, rose bengal and lissamine green is the most practical clinically. Fluorescein is the stain of choice to show corneal damage. Rose bengal is the choice for bulbar conjunctival damage. The new dye, lissamine green, is used as a substitute for rose bengal in the United States, and has the advantage that it does not sting. The mechanism of fluorescein staining is uncertain, with opinions differing. Whether it shows disruption of cell junctions (Feenstra & Tseng, 1992), or actual compromised or dead epithelial cells (Wilson et al, 1995), or not, fluorescein staining is the premier method of detecting defects of the corneal surface, especially surface defects in mild to moderate dry eye conditions, which typically would not stain significantly with rose bengal or lissamine green. The fluorescence of fluorescein is considerably enhanced if in addition to the cobalt blue excitation filter with the slit lamp illumination on max intensity, a yellow barrier filter is used (Wratten no12) on the viewing system Although Fluorescein staining is usually associated with corneal desiccation, it may occur with other causes, such as ocular rosacea, insult from staphylococcal exotoxins, infections and allergies amongst other causes. It is important to consider these are considered before arriving at a diagnosis of dry eye
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