Mechanisms of Global Support and Posttraumatic Enophthalmos

Long-Term Outcomes of Ultra-Thin Porous Polyethylene Implants used for Reconstruction of Orbital Floor Defects

“…Currently, orbital floor reconstruction in the setting of facial trauma has been one of the most common applications of porous polyethylene implants (Porex Surgical Inc., College Park, GA) with superior results. 2,5,6 It has proven biocompatibility, flexibility, and is remarkably stable. 7 Porous polyethylene sheets used in the orbit have desirable handling characteristics in addition to their porous structure, which enables vascular and tissue ingrowth, leading to further stabilization of the implant.…”

“…4,[8][9][10][11] Furthermore, the low incidence of complications in the orbit is remarkable given the number of implants that have been placed in contact with opened and contaminated facial sinuses. 6,12 The floor implant is forced to fall down into the maxillary sinus because of the weight of the orbital tissues influenced by gravitational forces. In this prospective study, we aimed to evaluate the long-term durability of the ultra-thin polyethylene sheet implants used for reconstruction of orbital floor defects for various causes.…”

Traumatic dislocation of the globe into the maxillary sinus associated with extraocular muscle injury

“…Preoperative CT scan of axial view (c) and coronal view (d) exhibit dislocation of the globe into the maxillary sinus with the large medial and inferior wall fractures lapse of the globe into the maxillary sinus. They suggested that the globe is suspended and supported within the orbit by the combination of the bulbar fascia (Tenon's capsule), extraocular muscles, ligaments, and orbital fat [3]. The globe does not sink significantly after the removal of the maxilla and orbital floor, indicating that these structures support the globe [6].…”

“…Only three patients manifesting this extreme form of trauma have thus far been reported [1,5,7]. However, these few cases were not reported to exhibit clear evidence of soft tissue injury, with regard to the bulbar fascia (Tenon's capsule), extraocular muscles, ligaments, and orbital fat, which all function as a support system for the globe [1][2][3]. In this report, we describe a patient who sustained this type of injury, exhibiting a clearly severed medial and inferior rectus, which is consistent with dysfunctions occurring in other supporting tissues.…”

Poly (96L/4D-Lactide) implants for repair of orbital floor defects: an in vitro study of the material properties in a simulation of the human orbit

“…Sometimes, natural dehiscences occur in the bony orbital floor [36]. However, over the entire spectrum of anatomical variation the position and function of the eye may be completely normal and undisturbed, even after removal of the bony orbital floor [5,37]. In addition, it is difficult to establish how long it takes before an orbital floor defect may be considered healed and strong enough to provide adequate support to the orbital contents without the risk of adverse sequelae in the long term, such as late enophthalmos or diplopia.…”