IOVS Journal of Clinical Microbiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

(Investigative Ophthalmology and Visual Science. 2006;47:4942-4946.)
© 2006 by The Association for Research in Vision and Ophthalmology, Inc.
DOI:  10.1167/iovs.06-0362
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Jackson, T. L.
Right arrow Articles by Marshall, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Jackson, T. L.
Right arrow Articles by Marshall, J.

Human Scleral Hydraulic Conductivity: Age-Related Changes, Topographical Variation, and Potential Scleral Outflow Facility

Timothy L. Jackson,1,2 Ali Hussain,1 Andrea Hodgetts,1 Ana M. S. Morley,1,2 Jost Hillenkamp,1,3 Paul M. Sullivan,2 and John Marshall1

1From the Academic Department of Ophthalmology, The Rayne Institute, GKT Medical School, London, United Kingdom; the 2Vitreoretinal Unit, Moorfields Eye Hospital, London, United Kingdom; and the 3University Eye Clinic, University of Regensburg, Regensburg, Germany.

PURPOSE. To measure the specific hydraulic conductivity (K) of human sclera over a range of ages, to assess topographical variation, and to provide a theoretical estimate of potential scleral outflow facility.

METHODS. Human donor sclera (n = 18; mean age 56.7 ± 25.9 years; range 4–89) was clamped in a modified Ussing chamber connected to a water column set at 15.7 mm Hg. Column descent was measured over 24 hours at 20°C with a digital micrometer. Scleral thickness of glutaraldehyde-fixed specimens was measured by light microscopy, taking the mean of 15 measurements per donor. Topographical variation in hydraulic conductivity (HC) was determined in an additional 10 donor eyes (mean age, 54.1 ± 26.4 years; range 12–89), comparing anterior, equatorial, and posterior sclera. The potential transscleral outflow facility was calculated by multiplying HC by total scleral surface area and adjusting water viscosity to core body temperature.

RESULTS. Mean K ± 1SD in adults (>18 years) was 5.85 ± 3.89 x 10–18 m2. K tended to be higher in pediatric donors, but there was no statistically significant age-related change. However, when all data sets were combined (n = 28), HC showed a significant decline with age. There was no significant topographical variation in HC. The potential transscleral outflow facility was 0.33 µL · min–1 · mm Hg–1.

CONCLUSIONS. Quantifying HC may help refine ocular pharmacotherapy, as transscleral water movement increases intraocular drug elimination and impedes transscleral drug delivery. The potential scleral outflow is two to three times higher than that which occurs in vivo; hence, medical or surgical interventions that fully exploit this pathway have considerable capacity to lower intraocular pressure.




This article has been cited by other articles:


Home page
 IOVSHome page
J. M. Stewart, D. S. Schultz, O.-T. Lee, and M. L. Trinidad
Exogenous Collagen Cross-linking Reduces Scleral Permeability: Modeling the Effects of Age-Related Cross-link Accumulation
Invest. Ophthalmol. Vis. Sci., January 1, 2009; 50(1): 352 - 357.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
T. L. Jackson, A. Hussain, A. M. S. Morley, P. M. Sullivan, A. Hodgetts, A. El-Osta, J. Hillenkamp, S. J. Charles, R. Sheard, T. H. Williamson, et al.
Scleral Hydraulic Conductivity and Macromolecular Diffusion in Patients with Uveal Effusion Syndrome
Invest. Ophthalmol. Vis. Sci., November 1, 2008; 49(11): 5033 - 5040.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
O. A. Anderson, T. L. Jackson, J. K. Singh, A. A. Hussain, and J. Marshall
Human Transscleral Albumin Permeability and the Effect of Topographical Location and Donor Age
Invest. Ophthalmol. Vis. Sci., September 1, 2008; 49(9): 4041 - 4045.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
M. Ciancaglini, P. Carpineto, L. Agnifili, M. Nubile, V. Fasanella, and L. Mastropasqua
Conjunctival Modifications in Ocular Hypertension and Primary Open Angle Glaucoma: An In Vivo Confocal Microscopy Study
Invest. Ophthalmol. Vis. Sci., July 1, 2008; 49(7): 3042 - 3048.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2006 by the Association for Research in Vision and Ophthalmology