Application of thermo-setting gel as artificial vitreous.
OBJECTIVE
In this study, we produced a rabbit model and investigated the safety of intravitreous injection of a thermo-setting gel (TG) to determine whether TG can be used as artificial vitreous.


METHODS
Ten male Japanese white rabbits were used. After performing vitrectomy in a unilateral eye, we injected 1 ml of WTG-127 into the vitreous cavity. The contralateral control eye was not given ophthalmic solution or surgery. Each eye was examined and intraocular pressure (IOP) and the electroretinogram (ERG) were evaluated. On day 28, all eyes were enucleated and examined.


RESULTS
No abnormal findings and no elevation of IOP were observed. On the ERG, no significant difference in the latency and amplitude of either the a wave or b wave was observed. Histopathological examination of the retinal tissue showed no abnormalities. In the presence of a retinal tear, under the detached retina a drift of TG through the tear was observed in a few animals.


CONCLUSIONS
In a rabbit model, the safety of using an intravitreous injection of thermo-setting gel as artificial vitreous was confirmed by ophthalmoscopic, electrophysiological, and histological studies for a relatively short observation period. However, TG injection cannot be expected to provide a tamponade effect.
Katagiri
Yoshiaki
Y
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan. yoshik@qj9.so-net.ne.jp.
Iwasaki
Takuya
T
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
Ishikawa
Tomoaki
T
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
Yamakawa
Naoyuki
N
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
Suzuki
Hidekazu
H
Wakamoto Pharmaceutical Company, Ltd., Tokyo, Japan.
Usui
Masahiko
M
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
D000818:Animals; D000869:Anterior Eye Segment / Q000166:cytology / Q000187:drug effects; D001187:Artificial Organs; D001672:Biocompatible Materials; D004338:Drug Combinations; D004596:Electroretinography; D005782:Gels / Q000008:administration & dosage*; D007267:Injections; D007429:Intraocular Pressure; D008297:Male; D008747:Methylcellulose / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000494:pharmacology; D011817:Rabbits; D012160:Retina / Q000166:cytology / Q000502:physiology; D012997:Solvents / Q000494:pharmacology; D013696:Temperature; D014821:Vitrectomy; D014822:Vitreous Body
D001672:Biocompatible Materials; D004338:Drug Combinations; D005782:Gels; D012997:Solvents; D011092:Polyethylene Glycols; D008747:Methylcellulose