SAN DIEGO, May 1, 2012 (GLOBE NEWSWIRE) -- TearLab Corporation (Nasdaq:TEAR) (TSX:TLB) ("TearLab" or the "Company") announced that a paper reporting on a multi-site refractive surgery center study designed to determine if pre-operative tear osmolarity levels relate to visual acuity outcomes following LASIK surgery will be presented at the Association for Research in Vision and Ophthalmology ("ARVO") Annual Meeting in Fort Lauderdale, Florida.
The presentation, entitled "Pre-surgical Hyperosmolarity Predicts Refractive Outcomes," will be given by study investigator, David C, Eldridge, OD FAAO, on Monday, May 7 at 9:45 A.M. ET.
A normal, healthy tear film is in homeostasis with the blood at a reference value of 290 mOsm/L. In dry eye disease, the tear film becomes unstable as the body loses the ability to control osmolarity, with levels exceeding the recognized cut-off of 308 mOsm/L, and eye-to-eye differences often greater than 8 mOsm/L.
In the current analysis, 128 refractive patients (256 eyes) were classified into one of two groups: normal or dry eye disease, defined as having an osmolarity greater than 308 mOsm/L in at least one eye prior to surgery. All patients followed each surgeon's standard post-surgical therapeutic regimen including fluoroquinolone, corticosteroids, and Abbott Medical Optics' Blink® Tears. TearLab® Osmolarity testing, fluorescein staining, as well as uncorrected Snellen visual acuity (UCVA) assessments were performed at screening, immediately prior to, one month post-, and three month post-surgery.
Patients with pre-operative hyperosmolarity demonstrated significantly worse UCVA at three months post-surgery (20/28 for hyperosmolar patients vs. 20/19 for normal subjects; p=0.018). All subjects enrolled in the study had the same visual acuity up to one month while they were on a suite of therapies including corticosteroids and Blink Tears. However, once therapy became uncontrolled, the vision of patients with pre-operative hyperosmolarity regressed significantly. These patients averaged a score of 0.2 out of 4 for ocular surface staining before surgery, making it virtually impossible to distinguish any differences between the two groups using that diagnostic method.
Dr. Eldridge commented, "These findings suggest that stabilizing the tear film prior to laser vision correction can help doctors to achieve a significantly better initial surgical outcome for patients with pre-operative hyperosmolarity. Importantly, they also indicate that, in order to maintain those initial outcomes and thereby reduce the potential need for future enhancement procedures, maintaining therapy for DED patients for an extended period of time following LASIK is necessary.