[Epikeratoplasty without sutures using collagen IV lens in monkeys: description of the surgical technic]. / Epikératoplastie sans suture avec lentille de Collagène IV chez le singe: description de la technique chirurgicale.

The authors describe their original epikeratoplasty technic without sutures which is compatible with the use of collagen IV lens. They describe the first four observations of primates operated on using this technic. At first the epithelium is removed at the cornea center and a trepanation is made of 4 mm diameter and 0.1 mm depth. The bottom of the trepanation is then cut horizontally, and the periphery of the lens is put in the cornea stroma. Later the epithelium will recover the collagen lens. The lens is perfectly set in the cornea. We don't use any suture and so we avoid astigmatism and neovascularisation. The follow-up consisted of biomicroscopic examination photography, specular microscopy, pachymetry, photokeratoscopy (Nidek System) tonometry and histology. Clinical observance showed a perfect lens tolerance. The cornea is immediately transparent and within a week epithelial cells recovered the lens of three animals out of four. The photokeratoscopy study proved the important cornea refraction modification. This technic is reversible and the lens can be exchanged. A study of histology has begun and already shows a pluristratified epithelium. Further studies will test the biomaterial stability and ultra structural relations between the collagen IV lens and epithelial cells.

[Human collagen IV lenses and epikeratoplasy in monkeys. Study of epithelial cicatrization]. / Lentilles de collagène IV humain et épikératoplastie chez le singe. Etude de la cicatrisation de l'épithélium.

A previous study showed the good tolerance of the human type IV collagen lenses implanted by epikeratoplasty in 8 monkeys. It also showed type IV collagen is a good material for the reepithelialization. But we have been interested in the stability of the epithelial healing. The ultrastructural study found anchoring structures. However these were inconstant. So the authors try to understand better the mechanisms of this synthesis of the anchoring structures and describe the future ways of this experimental study.