Deep Sclerectomy with Various Implants: An Experimental and Histopathologic Study in a Rabbit Model

Abstract

Background and Objective: To investigate the effectiveness of various implants used in experimental deep sclerectomy and to report tissue reactions developed to these implants histopathologically. Materials and Methods: Forty eyes of 40 New Zealand white albino rabbits underwent deep sclerectomy with various implants. The rabbits were divided into four groups; each consisted of 10 eyes. Deep sclerectomy was performed using copolymer materials in group 1, silicone materials in group 2 and chromic catgut suture in group 3. No implants were used in the control group (group 4). Clinical and histopathological examinations were performed to investigate the effectiveness of implants. Results: Mean preoperative intraocular pressure (IOP) was 14.4 ± 1.6 mm Hg in group 1, 14.5 ± 1.8 mm Hg in group 2, 13.8 ± 1.5 mm Hg in group 3 and 14.5 ± 1.2 mm Hg in group 4. The final postoperative IOPs were 10.7 ± 0.9, 10.6 ± 0.8, 13.5 ± 1.0, and 14.5 ± 1.4 mm Hg, respectively. At 2 months, the decrease in IOPs from baseline and the persistence of the filtering bleb were significantly marked in group 1 and group 2 (p < 0.001). Histopathological evaluation revealed that copolymer and silicone materials formed a smooth and regular intrascleral space. There were no foreign body reaction, tissue destruction or fibrosis in group 1 and group 2, but chromic catgut sutures caused severe fibrosis and inflammatory reaction in group 3. Mean histopathologic score of group 1, group 2, group 3 and group 4 was 0.7 ± 0.5, 0.8 ± 0.5, 2.4 ± 0.6, and 0.1 ± 0.3, respectively. Conclusion: Copolymer or silicone materials may increase the success rate of surgery by maintenance of a large and regular intrascleral space after deep sclerectomy and prevention of collapse of the flap.

Comparison of two prototypes of a magnetically adjustable glaucoma implant in rabbits

“…Hyphaema, being an intraoperative complication [8], was present in only one of the eight animals which is comparable with the hyphaema rates reported by Erkiliç et al [47] who performed deep sclerectomy with various implants (copolymer materials, silicon tubes, chromic catgut suture pieces). It must be taken into account that the complication of hyphaema is mostly dependent on the surgical techniques [11].…”

Deep sclerectomy augmented with combination of absorbable biosynthetic sodium hyaluronate scleral implant and mitomycin C or with mitomycin C versus trabeculectomy: long‐term results

“…They stated that the implant dissolved within 6–9 months and was replaced by new autologous scleral tissue, which formed a tunnel. In a study on an animal model, it was observed that non‐absorbable implants may fix the intrascleral space better than absorbable implants 43 . But T‐flux occupies a determined volume within the scleral lake.…”

“…In a study on an animal model, it was observed that non-absorbable implants may fix the intrascleral space better than absorbable implants. 43 But T-flux occupies a determined volume within the scleral lake. This may cause a decrease in the volume of lake and in the success rates when compared with cases in which SKgel implant were used.…”

In vivo biocompatibility assessment of (PTFE–PVDF–PP) terpolymer-based membrane with potential application for glaucoma treatment

“…In clinical evaluations the following endpoints were taken into consideration: pupil reaction to the light, light intolerance, leakage from conjunctival sac, swelling and inflammation of concjunctiva, sclera swelling and redness in wound area, postoperative scleral adhesions, time of wound healing and clinical status of the eyeball after 1 month observation. For evaluation of clinical lesions and wound healing the modified 4-graded scoring system (0-3) was adopted according to Hoekzem [18] and Erkiliç [19] (Table 1). …”