Download Ocular Imaging for Toxicology Studies

Ocular Imaging for Toxicology Studies: from Cornea to Retina
Abstract
Anterior Segment
Posterior Segment
The development of imaging equipment
designed for humans has also provided the
ability to image animal eyes. These
imaging techniques have been applied to
ocular toxicology studies and, with greater
frequency, to general toxicology studies.
They have the advantage of providing noninvasive, repeatable imaging of ocular
structures. Their use provides an
opportunity to reduce the number of
animals needed or to refine the use of
animals on study. The imaging techniques
may detect findings that are not visible via
routine ophthalmic examinations.
Depending on the species, handling
requirements range from manual restraint
to brief chemical restraint/sedation.
Limitations of repeated sedation would
reduce the frequency of imaging. With
appropriate use, these techniques enhance
ophthalmic evaluations during non-clinical
studies and provide endpoints that are
comparable to those used in clinical trials.
Non-contact spectral microscopy
(NCSM)
Fundus Imaging
Equipment
NIDEK CEM-530 specular microscope
•Corneal epithelium evaluation
•Corneal cell count
•Corneal thickness
Limitations
•Not interchangeable with pachymetry
•Large animal species only
•Sedation required
Fundus photography provides an image of
the fundus comparable to what an
examiner sees during an indirect
ophthalmic examination.
Fundus Autofluorescence (FAF)
•May detect changes that are not visible
during ophthalmic examinations
Optical coherence tomography
(OCT)
•Corneal thickness
•Corneal angle
•Iris imaging
OCT
Retina
•Retinal thickness
•Retinal defects
Heidelberg Spectralis® HRA+OCT
th
7
Ocular Diseases and Drug Discovery. San Diego, CA.
Margaret Collins, Taylor Mack, Collin Kolodziej; Charles River, Nevada
Limitations
•Not interchangeable with pachymetry
•Sedation required for large animal species
Posterior Segment
Limitations
•Sedation required
03/2015
Fundus Angiography
TopCon TRC-50EX Retina Camera
•Fluorescein angiography (FA)
•Indocyanin Green (ICG) angiography
•Retinal vessel integrity
Optic disc