Lens subluxation after plasmin and SF6 injections in rabbit eyes.
OBJECTIVE
To investigate the rate of lens subluxation following plasmin and/or SF6 injections in eyes, and whether a subsequent elevated level of vascular endothelial growth factor (VEGF) and vitreous tap would aggravate subluxation.


METHODS
Four groups of rabbits were used. Group 1 received an intravitreal injection (IVI) of plasmin and SF6 in the right eye; group 2 received an IVI of plasmin in the right eye; group 3 received an IVI of SF6 in the right eye; and group 4 received an IVI of balanced salt solution in the right eye. After treatment, IVIs of VEGF were given and vitreous tap was performed three times, followed by clinical observation of lens subluxation and scanning electronic microscope evaluation of the zonular fibers.


RESULTS
After IVIs of plasmin and SF6, and VEGF and vitreous tap had been performed one to three times, lens subluxation was noted in 0%, 43%, 71%, 71%, and 86% of the eyes in group 1. After IVIs of plasmin, VEGF, and vitreous tap had been performed one to three times, lens subluxation was noted in 11%, 22%, 44%, 44%, and 67% of the eyes in group 2. The eyes in group 3 and 4 did not show signs of lens subluxation after VEGF IVIs and vitreous tap. Histology confirmed zonular fiber damage in the eyes treated with plasmin.


CONCLUSIONS
The incidence of lens subluxation increased following plasmin injections in the eyes, and this was aggravated by the subsequent high VEGF level in the eyes and vitreous tapping. Zonular fibers were disrupted following plasmin treatment. These effects should be kept in mind when using plasmin enzymes in patients with vitreoretinal abnormalities.
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Wei-Chi
WC
Wu
Graduate Institute of Biochemical and Biomedical Engineering, Chang Gung University, Taoyuan, Taiwan.
Chi-Hsien
CH
Liu
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Nan-Kai
NK
Wang
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Kwan-Jen
KJ
Chen
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Tun-Lu
TL
Chen
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Yih-Shiou
YS
Hwang
Department of Health Care Administration, Oriental Institute of Technology, New Taipei City, Taiwan and Department of Business Administration, National Taiwan University, Taipei, Taiwan.
Pei-Ju
PJ
Liao
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Lien-Min
LM
Li
Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Chang Gung University, College of Medicine, Taoyuan, Taiwan.
Chi-Chun
CC
Lai
D000818:Animals; D005341:Fibrinolysin / Q000494:pharmacology*; D058449:Intravitreal Injections; D007906:Lens Subluxation / Q000378:metabolism / Q000473:pathology*; D007908:Lens, Crystalline / Q000187:drug effects* / Q000473:pathology; D008855:Microscopy, Electron, Scanning; D011817:Rabbits; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology; D013459:Sulfur Hexafluoride / Q000494:pharmacology*; D019108:Tight Junctions / Q000187:drug effects / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology
D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A; D005341:Fibrinolysin; D013459:Sulfur Hexafluoride