Download Tear film Hyperosmolarity and Dry Eye

Tear film
Hyperosmolarity
and Dry Eye
What is osmolarity?
Osmolarity is a measure of the osmotic pressure exerted by a solution across a semi-permeable membrane e.g.
in cellular walls of the corneal epithelium defined as the concentration of solutes (Osml/l). The osmolarity of
normal tear film is about 300 mOsm/l (isoosmolarity), but it can rise to around 340 mOsm/l (hyperosmolarity)
in patients with Dry Eye.
How does the tear film become hyperosmolar?
The main cause of tear film hyperosmolarity is an imbalance due to a reduced tear production and/or increased
tear evaporation. As a consequence, the concentration of solutes increases leading to hyperosmolarity of the
tear film.
What are the consequences of tear film hyperosmolarity in Dry Eye?
Recently, tear film hyperosmolarity has been regarded as the central mechanism causing ocular surface inflammation,
damage, and symptoms, triggering the initiation of compensatory events in Dry Eye.1
What are the benefits of a hypotonic eye drop formulation?
The excess of solutes and the lack of fluid of altered tears can be rapidly and effectively balanced with the
use of hypotonic eye drops which restore physiological tear film isoosmolarity.
Hyperosmolar tear film
Instillation of
hypotonic eye drops
Restoration of natural
tear film isoosmolarity
Ocular dryness score
Decrease of sensations
of ocular dryness
2.82
3.0
A hypotonic hyaluronic acid (HA) formulation
(150 mOsm/l) is significantly superior to an
isotonic HA solution in the treatment of
symptoms and signs of ocular dryness.2
1.89
2.0
1.0
Basal
0.50
After isoosmolar
HA-solution (0,4%)
After hypoosmolar
HA-solution (0,4%)
0.0
The VISMED® range of hypotonic preservative free HA-based lubricant eye drops
counteracts tear film hyperosmolarity in patients with sensations of ocular dryness
Hypotonic hyaluronic acid for all your needs
1. The Ocular Surface. DEWS Definition and Classification 2007; 5(2): 75-92.
TRB CHEMEDICA INTERNATIONAL SA
Geneva - Switzerland
Tel: + 41 22 703 49 00 - Fax: + 41 22 703 49 01
[email protected]
www.trbchemedica.com
2. Troiano P et al. Effect of hypotonic 0.4 % hyaluronic acid drops in
dry eye patients: a cross-over study. Cornea. 2008 Dec; 27 (10): 1126–30.
TRB CHEMEDICA AG
Richard-Reitzner-Allee 1
85540 Haar/München, Germany
DUOVISUAL - GENEVA - CH - 5553 - 04/08 VISM-10a
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