[Experimental evaluation of conjunctival reconstruction using a collagen membrane]

Surgical reconstruction of the conjunctiva using collagen represents a promising approach due to its biocompatibility and capability to support intrinsic regeneration.

This study evaluated the effect of collagen membrane implantation on the healing of bulbar conjunctival defects in an in vivo experiment.

The study was conducted at the Krasnov Research Institute of Eye Diseases on 32 Chinchilla rabbits (64 eyes). Bulbar conjunctival defects with diameters of 4, 5, and 6 mm were induced in animals of the control group, while a collagen membrane (CM) with a collagen concentration of 30 mg/ml was implanted in the experimental group. Efficacy criteria included the severity of vascular injection during healing, time to complete epithelialization, adaptation of the CM implant to the sclera, cellular integration into the membrane, and presence of fibrosis in the newly formed tissue. Biomicroscopy with photographic documentation and optical coherence tomography (OCT) (SOLIX, Optovue) were performed. Histological samples were collected at 1, 3, and 6 months of the follow-up.

In the experimental group, no vascular injection was observed at 30 days, whereas the control group demonstrated persistent pronounced inflammatory response (Student's t-test: p=0.0015, p<0.0001, p<0.0001). Complete epithelialization occurred significantly earlier in the experimental group compared with the control group (10.31±2.0723 days vs 15.94±2.608 days, respectively; p<0.0001, Wilcoxon test). OCT findings confirmed proper adaptation of the implant to the underlying sclera and the presence of epithelialization. At 3 months, histological examination demonstrated cellular migration into the CM, and at 6 months - complete restoration by newly formed native tissue without signs of fibrosis in the defect area.

The developed surgical technique of collagen membrane implantation is effective and minimally traumatic. It represents a safe and efficient method that accelerates conjunctival defect healing and shows potential for its application in conjunctival reconstruction in clinical practice.