In vivo study comparing an X-shaped polymethylmethacrylate and a cylindrical collagen implant for deep sclerectomy.
BACKGROUND
Study in vivo characteristics of a polymethylmethacrylate (PMMA) implant compared to the standard cylindrical collagen implant for deep sclerectomy (DS).


METHODS
Six-month comparative study.


METHODS
Twenty eyes of ten rabbits.


METHODS
Eyes were randomized to have DS with PMMA implant in one eye and collagen implant in the opposite eye. The growth of the new subconjunctival drainage vessels was assessed by combined fluorescein and indocyanin green anterior segment angiography; intrascleral and subconjunctival blebs were imaged by ultrasound biomicroscopy (UBM). At six months, outflow facility (C) was measured by anterior chamber perfusion and portions of one side of the DS were compared to portions on the 180° opposite side and native sclera on histology.


RESULTS
The mean IOP preoperatively and at one, four, twelve, and twenty-four weeks was comparable in both groups (P > 0.1). UBM showed a statistically insignificant quicker regression of the subconjunctival bleb as well as a durable intrascleral lake in the PMMA group (P > 0.05). New drainage vessels were initially observed one month after surgery; they were more numerous in the PMMA group on angiographic and histological findings at 6 months (P < 0.05). The mean C increased significantly after surgery compared to preoperative values (P < 0.05) and no difference was observed between the implants (0.24 ± 0.06 µl/min/mmHg [PMMA] and 0.23 ± 0.07 µl/min/mmHg [collagen implant]) (P = 0.39).


CONCLUSIONS
Deep sclerectomy performed with PMMA or collagen implants showed similar IOP lowering effects, outflow facility increase, and degree of inflammatory reaction.
Glaucoma Unit, Jules Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland.
Andrea
A
Codreanu
Hoai V
HV
Tran
Christophe
C
Wiaux
Kaweh
K
Mansouri
Sylvain
S
Roy
Andre
A
Mermoud
Corinne
C
Schnyder
D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D001672:Biocompatible Materials; D003094:Collagen; D003228:Conjunctiva / Q000098:blood supply; D005451:Fluorescein Angiography; D007429:Intraocular Pressure / Q000502:physiology; D033401:Microscopy, Acoustic; D019904:Polymethyl Methacrylate; D019736:Prostheses and Implants; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D011817:Rabbits; D012590:Sclera / Q000000981:diagnostic imaging / Q000601:surgery*; D012599:Sclerostomy; D013524:Surgical Flaps
D001672:Biocompatible Materials; D003094:Collagen; D019904:Polymethyl Methacrylate