Transcellular Aqueous Humor Outflow: A Theoretical and Experimental Study

  • A. Eriksson
  • B. Svedbergh
Conference paper
Part of the Current Research in Ophthalmic Electron Microscopy book series (CR OPHTHALMIC, volume 3)


When the aqueous humor passed through the transcellular channels of the inner wall endothelium of Schlemm’s canal the flow was estimated to be very slow and viscous (Reynolds’ number about 10-3). It was found to be accurate to treat this extreme flow situation with conventional hydrodynamic formulae without specific corrections. Four different principal configurations of the transcellular channels were investigated. The theoretical calculations yielded results in good agreement with those obtained from the experimental model studies. Where deviations occurred they were probably explained by a radial flow component, which was not incorporated in the theoretical formulae applied. A spherical channel configuration was considered most similar to the in vivo situation and this yielded experimental resistance values half those of previously applied theoretical methods. Using previous morphological data the present results indicated that less than 5% of the total resistance to aqueous humor outflow was located in the inner wall endothelium in normal human eyes, and about 10% in cynomolgus monkey eyes at normal intraocular pressure.


Aqueous Humor Cone Angle Pore Radius Trabecular Meshwork Radial Flow 
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Copyright information

© Springer-Verlag Berlin · Heidelberg 1980

Authors and Affiliations

  • A. Eriksson
    • 1
  • B. Svedbergh
    • 2
    • 3
  1. 1.The Department of AerodynamicsAeronautical Research Institute of SwedenStockholmSweden
  2. 2.The Department of Physiology and Medical BiophysicsUniversity of UppsalaUppsalaSweden
  3. 3.The Department of OphthalmologyKarolinska HospitalStockholmSweden

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