الفهرس 
Anatomy and physiology of Lacrimal SystemOnly 14 pages are availabe for public view
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Abstract
Dry eye is a disorder of the tear film due to tear deficiency or excessive
tear evaporation which causes damage to the interpalpebral ocular surface and
is associated with symptoms of ocular discomfort.
The current understanding of the pathogenesis of DES has proceeded
from the mere recognition of a lack of, or altered quality of tears to
recognition of inflammation as the key pathogenetic mechanism, whether
from a systemic autoimmune disease or a local autoimmune event.
Clinical features of DES include an unstable tear film, ocular surface
inflammation, and epitheliopathy, resulting in symptoms ranging from
discomfort to blindness.
An established sequence of diagnostic tests is desirable to prevent one
test from interfering with another. They include clinical diagnostic tests such
as Grading ocular surface staining, Tear break up time, and Schimer’s test.
Histopathological tests such as impression cytology, conjunctival and labial
salivary gland biopsy. Laboratory tests include Tear flourescein clearance,
tear function index, tear osmolarity, analysis of protein, lactoferrin, tear
lysozyme and leukocyte esterase in tears. Study of lipid layer that involves
meibometry, lipid layer thickness, and lipid layer appearance.
Emerging technologies as reflective meniscometry, optical coherence
tomography and ocular surface thermographer use in diagnosis of DES.
Significant advances have been made in treating the many facets of dry
eye, but it remains a disorder of long-term maintenance rather than permanent
cure.
Many years ago, the traditional approach to treating dry eye has been
to lubricate the ocular surface by either replacing or conserving the
patient’s tears.
Summary
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Tear supplementation is the first line of treatment, artificial tears
increase available tears and lower tear osmolarity through dilutional effects,
however, significant advances have been made in treating many facets of dry
eye including; non preserved tear preparations, autologous serum and
umbilical cord serum eye drops, punctual plugging, hydrogel soft contact
lenses and Boston sclera lens prosthetic device as a method for tear
preservation.
Corticosteroids, cyclosporine A, and tetracyclinshave all been used
with success to treat the secondary inflammatory response and consequential
cellular changes of dry eye.
The omega-3 revolution with TheraTears Nutrition for dry eyes is a
new approach to dry eye treatment. It is a supplement containing a blend of
flaxseed oil, fish oil and vitamin E. TheraTears Nutrition will be taking a
major role in the treatment of dry eyes, addressing the conditions that lead to
increases in tear film osmolarity.
Surgical treatment is indicated in severe cases of dry eye that are
refractory to other methods of treatment. It must not be given as an isolated
act, but should be combined with the psychological, medical and
environmental treatments. It involves punctual occlusion, stem cell
transplantation.
Recent antiiflammatory drugs are Tacrolimus, IL-Ra, Resolvin E1
(Rx-10001) and Chemokine Receptor Antagonist.
Recent compounds use in treatment of DES as Calcineurin and mTOR
inhibitors, Serotonin receptor inhibitors, Calcium activated chloride channelmodulators and Anti-lymphangiogenic agent.