April 2014
Volume 55, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2014
Digital mini-shadowphotogrammetric system for morphometric analysis of ex-vivo crystalline lenses: Pilot study on human lenses
Author Affiliations & Notes
  • Ashik Mohamed
    Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
    School of Optometry and Vision Science, University of New South Wales, Sydney, NSW, Australia
  • Heather Ann Durkee
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
  • Robert C Augusteyn
    School of Optometry and Vision Science, University of New South Wales, Sydney, NSW, Australia
    Brien Holden Vision Institute and the Vision Cooperative Research Centre, Sydney, NSW, Australia
  • Raksha Urs
    Department of Ophthalmology, Columbia University Medical Center, New York, NY
  • Victor Hernandez
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
    Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL
  • Andres Bernal
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
  • Fabrice Manns
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
    Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL
  • Arthur Ho
    School of Optometry and Vision Science, University of New South Wales, Sydney, NSW, Australia
    Brien Holden Vision Institute and the Vision Cooperative Research Centre, Sydney, NSW, Australia
  • Jean-Marie A Parel
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
    Brien Holden Vision Institute and the Vision Cooperative Research Centre, Sydney, NSW, Australia
  • Virender S Sangwan
    Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
    Brien Holden Vision Institute and the Vision Cooperative Research Centre, Sydney, NSW, Australia
  • Footnotes
    Commercial Relationships Ashik Mohamed, None; Heather Durkee, None; Robert Augusteyn, None; Raksha Urs, None; Victor Hernandez, None; Andres Bernal, None; Fabrice Manns, None; Arthur Ho, None; Jean-Marie Parel, None; Virender Sangwan, None
  • Footnotes
    Support None
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 747. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Ashik Mohamed, Heather Ann Durkee, Robert C Augusteyn, Raksha Urs, Victor Hernandez, Andres Bernal, Fabrice Manns, Arthur Ho, Jean-Marie A Parel, Virender S Sangwan; Digital mini-shadowphotogrammetric system for morphometric analysis of ex-vivo crystalline lenses: Pilot study on human lenses. Invest. Ophthalmol. Vis. Sci. 2014;55(13):747. doi: https://doi.org/.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract
 
Purpose
 

To examine the morphometry of human crystalline lenses using a miniature shadowphotogrammetric system.

 
Methods
 

Crystalline lenses (n = 41, aged 10 months-88 years, median post-mortem time 25 hours (interquartile range, 19-34 hours)) were isolated from eyes received from the Ramayamma International Eye Bank, Hyderabad, India. The sagittal and coronal profiles of the lenses were imaged using a custom-built digital optical system based on the principle of shadowphotogrammetry. The experimental setup is an improvement on the study by Augusteyn et al (Mol Vis 2006) which used an industrial optical comparator. Analysis of the coronal and sagittal images was performed using custom MATLAB-based software. The sagittal lens contour was fit to a 10th order even Fourier series (Urs et al Vis Res 2010) and thickness and diameter measurements were made. Conic and spherical functions were applied to anterior and posterior lens surfaces for central 6mm and 3mm zones, respectively.

 
Results
 

The system’s ~6.4 µm/pixel resolution of images enabled accurate fits of the detected lens contours. Analysis took ~5 minutes/lens. Rapid changes were observed in the young lenses in all dimensions obtained from the lens profiles, but at this time insufficient data are available to permit detailed analyses. Adult lens diameter, thickness (T), anterior T and posterior T increased at 0.013mm, 0.009mm, 0.003mm and 0.006mm per year, respectively. The relationship between age and cross-sectional area (mm2), surface area (mm2) & volume (mm3) for adult lenses were described using the following power equations: y = 14.51x0.2, y = 100.35x0.16 & y = 67.42x0.27 respectively. After age 18 years, the anterior radii (R) of curvature for the central 6mm and 3mm zones were 8.05±2.45mm and 8.78±2.21mm respectively, whereas the posterior R ranged between 4.52-6.99mm and 4.70-7.58mm respectively. The shape factors for anterior and posterior surfaces were 9.94±8.76 and 0.14±1.09 respectively.

 
Conclusions
 

All lens parameters increased as a function of age, consistent with continuous lens growth. The information obtained from morphometric analysis of a large number of isolated human lenses over a wide age range will be valuable in the development of biomechanical simulation and optical modeling of natural and artificial crystalline lenses.

 
 
Mini-Shadowgraph System
 
Mini-Shadowgraph System
 
 
Representative Sagittal and Coronal Images
 
Representative Sagittal and Coronal Images
 
Keywords: 413 aging • 551 imaging/image analysis: non-clinical • 419 anatomy  
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×