Comparison of collagen membranes and polydioxanone for reconstruction of the orbital floor after fractures.

Orbital floor fractures, often combined with zygomatic fractures, are common fractures of the midface. Surgery of orbital fractures is done to free incarcerated or prolapsed orbital tissue and to restore the anatomic skeletal size of the orbit. Lyodura was a standard for the reconstruction of the orbital floor until cases of Creutzfeldt-Jakob disease were reported, so that polydioxanone (PDS) is widely used today. However, infections around the implant are reported. In a randomized controlled clinical study on 24 patients with orbital floor defects of approximately 1 cm, we evaluated the use of a collagen membrane compared with a PDS foil. Computed tomography controls and ophthalmologic examinations were performed after 6 months in 10 patients per group.Intraoperative complications occurred neither in the collagen membrane group nor in the PDS group. In case of orbital rim fractures, the collagen membrane could additionally cover these defects. Perioperatively and postoperatively, no complications such as infections were observed. After 6 months, computed tomography controls revealed a complete reposition of orbital tissue and even bone regeneration in both groups. Diplopia and hypoesthesia were completely reversed after half a year.Smaller defects (up to 1 cm) of the orbital floor can be restored with a PDS foil or a collagen membrane. However, for larger defects, stability may not be sufficient.