Comparison of precorneal tear film stability and basal tear secretion rates in contact lens wearers versus non-wearers

72 Pages·1992·2.8 MB·English

by  Tantisira, Jivin Gerard

YALE
MEDICAL LIBRARY
Permission for photocoping or microfilming of "_C
c <~t Ce^s' w (Title of thesis)
for the purpose of individual scholarly consultation or reference
is hereby granted by the author. This permission is not to be
interpreted as affecting publication of this work or otherwise
placing it in the public domain, and the author reserves all rights
of ownership guaranteed under common law protection of unpublished
manuscripts.
Signature of Author
, A
-z/9
Date
Digitized by the Internet Archive
in 2017 with funding from
Arcadia Fund
https://archive.org/details/comparisonofprecOOtant
COMPARISON OF PRECORNEAL TEAR FILM STABILITY AND BASAL TEAR
SECRETION RATES IN CONTACT LENS WEARERS VERSUS NON¬
WEARERS
A Thesis Submitted to the Yale University
School of Medicine in Partial Fulfillment
of the Requirements for the Degree of
Doctor of Medicine
by
Jivin Gerard Tantisira
>
f \
1992
\v\fd
ABSTRACT
COMPARISON OF PRECORNEAL TEAR FILM STABILITY AND BASAL TEAR
SECRETION RATES IN CONTACT LENS WEARERS VERSUS NON¬
WEARERS
Jivin Gerard Tantisira
1992
Precorneal tear film break-up times (BUT) as a measure of tear film
stability and Schirmer tests after topical anesthetic (ST) as a measure of basal
tear secretion rate were performed on contact lens wearers and non-contact
lens wearers (normals). BUT was negatively correlated with age although the
R-squared indicated that the strength of the covariation was weak. ST was not
found to be significantly correlated with age. People who reported having a
history of dry eyes had significantly (P<.02) lower average BUTs (8.1 +/- 7.4
sec) than normals(14.0 +/- 6 sec), as well as significantly lower average STs
(3.4 +/- 1.9 mm) than normals (10.7+/- 5.6 mm)(P<.01). The presence of
superficial punctate keratitis was also associated with both significantly lower
BUTs(Pc.QOI) and STs (P<.001). The type of contact lens worn had no
significant effect on average BUT(P>.05), however it did result in significantly
different average STs(P<.05). Soft lens wearers were found to have a
significantly lower average ST (4.9 +/- 3.5 mm) than normals(9.4 +/- 6.1 mm).
Although extended lens wearers had a lower average ST (6.0 +/- 4.0 mm) than
normals, this difference was not significant. There was no significant difference
detected in average ST between gas permeable lens wearers and normals.
The soft and extended contact lens wearers with one or more contact lens

problems had lower average BUTs (7.1 +/- 5.03 sec) and STs (2.93 +/- 2.42
mm) than the control contact lens groups without problems (BUT = 12.5 +/- 7.36
sec, ST = 6.20 +/- 3.61 mm), and these results were close to being statistically
significant (P=.063).