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Posters
November 2003
Duration of Discontinuation from
Silicone Hydrogel Extended Wear Due to Non Infectious Adverse
Responses
Katie Edwards, Thomas Naduvilath, Nina Tahhan,
Renee Du Toit, Eric Papas, Angela Kalliris, Jerome Ozkan, Deborah
F Sweeney . CCLRU,
School of Optometry and CRCERT, University of New South Wales, Kensington,
Australia.
Purpose:
Most adverse ocular events (AE)
occurring with extended wear of silicone hydrogels resolve with
temporary discontinuation of lens wear. A retrospective study
to assess the average length of discontinuation due to AEs was
conducted.
Methods:
282 subjects wore bilateral
silicone hydrogel lenses on a 30N EW schedule. Subjects were
reviewed at 1 night, 1 week, 1 month, then at 3 monthly intervals,
and if experiencing unusual signs or symptoms. If an AE was diagnosed,
lens wear was discontinued until the condition had completely
resolved. AEs were graded in severity on a scale of 1-4 and classified
as Corneal Inflammatory Events (CIE): Contact Lens Peripheral
Ulcer (CLPU), Contact Lens induced Acute Red Eye (CLARE), Infiltrative
Keratitis (IK), and Mechanical Events (ME): Superior Epithelial
Arcuate Lesion (SEAL), Corneal Erosion (CE). The length of discontinuation
due to different AEs was compared and the associations with severity
ratings and clinical variables examined.
Results:
On average, CIEs caused longer
durations of discontinuation (15±15 days) than MEs (5±3
days)(p<0.01). There were no differences in length of discontinuation
between different types of CIEs (CLPU: 11±8; CLARE: 12±8;
IK: 17±17; p=1.0), or between different types of MEs (SEAL:
5±4; CE: 5±3; p=1.0). Length of discontinuation
following CIEs, but not with MEs, correlated with severity rating
(r=0.46, p<0.01), density of infiltrate (r=0.27, p=0.04),
and depth of corneal staining (r=0.27, p=0.03).
Conclusions:
Most AEs with silicone hydrogels are self
limiting, with lens wear resuming on average within 15 days of
CIEs and 5 days of MEs. Denser infiltrates and deeper staining
in CIEs are associated with longer periods of discontinuation
from lens wear.