Age differences in corneal hydration control.
Invest Ophthalmol Vis Sci
; 30(3): 392-9, 1989 Mar.
Article
em En
| MEDLINE
| ID: mdl-2925313
ABSTRACT
Dynamic changes in corneal thickness were measured in eight young and eight older normal subjects (mean ages 24.4 +/- 4.3 years and 71.9 +/- 7.3 years, respectively) to provide data for quantitative assessment of corneal hydration control and thereby provide information for studying age differences in this important aspect of corneal function. For each subject, pachometry data were obtained by (A) monitoring corneal recovery following hypoxic stress, and by either (B1) measuring recovery after sleep or (B2) by measuring corneal thickness in the late afternoon. The combined data from A and B1 or A and B2 were analyzed through an exponential model to provide information on the (1) percent recovery per hour (PRPH) following induced corneal hydration; (2) open-eye steady-state (OESS) corneal thickness; (3) residual corneal swelling just before the hypoxic stress test; (4) amount of corneal edema induced by hypoxic stress; and (5) time to reach 95% recovery back to the OESS thickness level (T95%). The results show that between the two age groups, there are substantial differences in some characteristics of corneal hydration while other aspects are similar. For example, the mean PRPH values (58.9 +/- 7.8% and 34.2 +/- 6.4%/hr) were significantly higher in the younger subjects (P = 0.0002) and the mean time for 95% recovery to OESS thickness (207 +/- 42 min and 452 +/- 117 min) was significantly lower in the younger vs. the older group (P = 0.0002).(ABSTRACT TRUNCATED AT 250 WORDS)
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água Corporal
/
Envelhecimento
/
Córnea
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
Limite:
Adult
/
Aged
/
Humans
Idioma:
En
Revista:
Invest Ophthalmol Vis Sci
Ano de publicação:
1989
Tipo de documento:
Article