TY - JOUR
TI - Intravitreal application of ganciclovir in rabbits: ERG and
electron-microscopic findings
AU - Moschos, M
AU - Vamvasakis, M
AU - Kontogeorgos, G
AU - Papantonis, F and
AU - Panagakis, E
AU - Chatzis, V
JO - Ophthalmologica Extra
PY - 1996
VL - 210
TODO - 4
SP - 215-222
PB - Karger
SN - 2296-1445
TODO - 10.1159/000310712
TODO - rabbit; ganciclovir; cytomegalovirus retinitis; vitreous body; retina;
electroretinography; electron microscopy
TODO - The retinal toxic effect after intravitreal use of ganciclovir has been
the subject of our experimental investigation on 20 New Zealand rabbits.
Different doses of ganciclovir ranging from 200 to 600 mu g/0.1 mi were
injected intravitreously, and ERG changes were recorded at different
time points after drug administration. Finally the animals were killed
and the retinal lesions were studied by electron microscopy. According
to our experiments, ganciclovir doses of 300-600 mu g0.1 mi have a
clearly toxic effect on the retina as shown by ERG changes. One month
after the injection, the electroretinogram is either extinguished or
clearly affected. Noteworthy is the fact that in a dose of 200 mu g/0.1
mi, the ERG b-wave shows a 20% reduction of its normal amplitude 4
months after ganciclovir delivery. Electron microscopy of the retina
revealed in the inner segment of the receptor cells the existence of
dilatation and vesiculation of the endoplasmic reticulum in the
surrounding nuclear cytoplasm and swelling of the mitochondria with
fragmentation of the cristae in several of them. In the outer segment of
the photoreceptor cells, degeneration and destruction of the lamellae
accompagnied by disintegration of the adjacent protoplasm in parts of
certain rods and cones appeared. Finally large vacuoles of irregular
shape in the synapses and degenerative mitochondria and empty vacuoles
in the optic nerve fibers were shown.
ER -