Abstract
Purpose:
To evaluate a previously published model of choroidal neovascularization (CNV) in Dutch-Belted rabbits (Ni et al 2005) using a modified procedure.
Methods:
15 (3 in the first cohort and 12 in the second cohort) young adult Dutch-Belted rabbits were used and a total of 18 eyes were given subretinal injections of heparin-sepharose beads with fibroblast growth factor and LPS (100 ng bFGF, 100 ng LPS in 50 µl of ~3% collagen gel, pH 7-7.2). Instead of a single step subretinal injection with a 30G needle as previously published (Ni et al 2005), a 2-step injection technique was used. After insertion of a 23G cannula through the pars plana, a 41G needle (Dutch Ophthalmic Research Center) was used to create a subretinal bleb with balanced salt solution followed by subretinal injection of the mixture with a blunt 26G needle through the same retinotomy. Bruch’s membrane was then perforated at the visual streak with a sharp 30 gauge needle. Angiography with either sodium fluorescein or FITC-dextran were taken periodically. In the first cohort of eyes, the lesions were followed for 13 weeks. In the second cohort of 12 eyes, 6 were control and 6 were treated with intravitreous ranibizumab once on Week 3. Area of the lesions on weeks 3 and 5 was quantified with ImageJ.
Results:
Approximately 60% of all injected eyes showed noticeable CNV-like lesions at 2 weeks and thereafter. In the first cohort of 4 eyes, the lesions showed growth in the first 6 weeks and then stabilized. All those lesions remained similar at Week 13. In the second cohort of eyes, similar CNV-like lesions were noted. Treatment with ranibizumab inhibited the growth of CNV-like lesions as evaluated with FITC-dextran angiography on Week 5 (P<0.001).
Conclusions:
Persistent CNV-like lesions were produced in Dutch-Belted rabbits using a procedure modified from an earlier publication. The model was validated using ranibizumab as a positive control.
Keywords: 412 age-related macular degeneration •
453 choroid: neovascularization