Biomedical Engineering Reference
In-Depth Information
Fig. 41 Histologic section of the posterior globe in a rat demonstrating a
persistent hyaloid remnant (arrow)
higher prevalence in females [
48
]. On a pretest examination, ani-
mals with PPM/PH and associated hemorrhage (vitreous, aque-
ous) should typically be eliminated from the study if possible
(Fig.
14
). Anterior synechia, microophthalmos, and anterior cleav-
age anomalies are also occasionally seen as congenital ocular
anomalies in rats and mice.
The term corneal dystrophy implies a bilateral, noninflamma-
tory inherited, degenerative disorder and is a specific term. Unfor-
tunately, the terms corneal opacity or corneal crystals are also used
and are less specific and more general terms. The term calcific band
keratopathy has also been applied to the lesions observed in rodents
[
43
]. Clinically, the lesions of corneal dystrophy most commonly
appear as fine granular or linear opacities in the nasal and axial
palpebral fissure (Figs.
17
-
19
). They are most frequently bilateral.
Histologically, corneal dystrophy in rodents is typically a basement
membrane, anterior stromal corneal defect resulting in deposits of
mineral and phospholipid in and adjacent to the epithelial basement
membrane (Fig.
42
)[
34
,
43
]. Corneal dystrophy, while common in
a pretest examination, will be observed to increase in prevalence
and severity with age. Corneal dystrophy is common in rats and less
