In Vivo and In Vitro Feasibility Studies of Intraocular Use of Seprafilm to Close Retinal Breaks in Bovine and Rabbit Eyes

Abstract

Seprafilm, a sodium hyaluronate/carboxymethylcellulose absorbable barrier developed to prevent adhesions after abdominal surgery, adheres well to wet tissue. The authors studied the efficacy of this film for sealing retinal breaks in animals. In an in vitro study, a retinal detachment with a hole was created in bovine eyecups after the vitreous gel was removed. Seprafilm was placed over the retinal hole, and the strength of the retinal adhesion was measured by pulling the film. Permeability was tested by applying methylene blue to the film covering the retinal break. Seprafilm also was soaked in balanced salt solution (BSS) incubated at 37 degrees C, and the pH of the BSS containing Seprafilm was measured as it melted. In an in vivo study, Seprafilm was powdered and mixed in BSS solution, and 0.1 mL was injected into the right vitreous cavity in study rabbits. The same amount of BSS was injected into the right vitreous cavity in control rabbits. Ophthalmologic examinations were performed. Bilateral electroretinograms were recorded simultaneously before and 6 weeks after injection. Both eyes were enucleated for histologic evaluation. Seprafilm adhered well to the retina, was impermeable to methylene blue, and remained solid in BSS for 30 days before it dissolved, and its pH ranged from 7.2 to 8.0. No intraocular inflammatory reaction occurred after intravitreous injection of Seprafilm solution. There was no significant difference in amplitudes or implicit times of electroretinogram a-waves, b-waves, and oscillatory potentials before and after injection and between study and control groups. No significant retinal abnormality was detected by light microscopy in either group. The film adhered well to the retina with no signs of ocular toxicities. Further study is warranted for possible means of patching retinal breaks.