Br J Ophthalmol 1999;83:967-972
( August )
New animal model for human ocular toxocariasis: ophthalmoscopic
observation
Tomoko Hara Takayanagi, Nobuaki Akao, Ryoko Suzuki, Misato Tomoda, Setsuko Tsukidate, Koichiro Fujita
Department of
Medical Zoology, Faculty of Medicine, Tokyo Medical and Dental
University, Tokyo, Japan
Correspondence to: Dr Koichiro Fujita, Department of Medical Zoology, Faculty of Medicine,
Tokyo Medical and Dental University, 1-5-45 Yushima Bunkyo-ku,
Tokyo113-8519, Japan.
Accepted for publication 29 March 1999
BACKGROUND/AIMS
Although
human ocular toxocariasis causes severe vision defect, little is known
about its aetiology, diagnosis, and treatment. To develop a new animal
model for human ocular toxocariasis, ophthalmological findings of fundi
in Mongolian gerbils, Meriones unguiculatus, and BALB/c mice were investigated following infection with
Toxocara canis.
METHODSUsing an
ophthalmoscope, which was specifically developed to observe the fundi
of small animals, ocular changes of fundi of 20 gerbils and 11 mice
were monitored after oral infection with embryonated eggs of
T canis.
RESULTSVitreous,
choroidal, and retinal haemorrhages were consistently observed in
Mongolian gerbils, but rarely in mice. Severe exudative lesions and
vasculitis were often present in gerbils but not in mice. Migrating
larvae were also frequently observed in gerbils.
CONCLUSIONMongolian
gerbils are more appropriate animal model for human ocular toxocariasis
than previously used experimental animal such as mice, guinea pigs,
rabbits, and monkeys because of its high susceptibility of ocular infection.
© 1999 by British Journal of Ophthalmology
