Determination of Ocular Blood Flows with the Microsphere Method

  • Siv F. E. NilssonEmail author
  • Albert Alm

Core Messages

  • The advantages with the microsphere method are: (1) it measures blood flow directly, (2) it is suitable for measuring blood flow in small pieces of tissue and in inaccessible tissues, and (3) it does not disturb the normal circulation, if the experiments are properly designed.

  • Radioactive, colored, and fluorescent microspheres have been used for determination of ocular blood flow. A promising new development is the use of neutron-activated microspheres.

  • For reliable measurements with the microsphere method, the size and number of microspheres should be optimized for the tissue under investigation.

  • If few microspheres are trapped in a ­tissue, due to low blood flow and/or small sample size (e.g., retina and anterior uvea), the precision of the determinations can be increased by more experiments.

  • Biological variation contributes more to the error in the measurements than paucity of microspheres.

  • Differences in arterial blood pressure, anesthesia, and arterial blood gases...


Blood Flow Mean Arterial Blood Pressure Ciliary Body Measure Blood Flow Large Sphere 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Authors and Affiliations

  1. 1.Division of Drug Research/Pharmacology, Department of Medical and Health Sciences – IMH, Faculty of Health SciencesUniversity of LinköpingLinköpingSweden
  2. 2.Division of Ophthalmology, Department of NeurosciencesUniversity Hospital, University of UppsalaUppsalaSweden

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