Proctase-treated collagen gels were injected into the vitreous cavity in 16 patients with retinal detachments that were considered inoperable by current scleral buckling techniques. Opacification of the gels and a transient inflammatory response were observed, but the vitreous cavity cleared within two weeks in 11 of the 16 eyes (69%). Anatomic reattachment was obtained in three patients (19%), and useful vision was recovered by two patients (13%). Further investigation is necessary before collagen gel can be recommended as an adjunct to retinal detachment surgery.
Pruett RC, Schepens CL, Freeman HM. Collagen Vitreous SubstituteII. Preliminary Clinical Trials. Arch Ophthalmol. 1974;91(1):29-32. doi:10.1001/archopht.1974.03900060033008