Reconstruction of orbital floor defects assisted by transantral endoscopy

Repair of orbital floor fractures via the transantral approach with osteosynthesis plate

INTRODUCTION

The most common surgical access techniques employed in patients with orbital floor fractures are associated with a risk of complications, such as implant infection, migration, epiphora, lower eyelid retraction, ectropion, diplopia worsening, retrobulbar hematoma, emphysema, "white-eyed" syndrome, enophthalmia relapse, hypoglobus, and persistent diplopia due to periorbital atrophy. Consequently, alternative access techniques precluding these complications have to be found.

STUDY OBJECTIVE

To assess the efficacy of transantral approach in the surgical treatment of patients with orbital floor fractures based on results of retrospective analysis of our clinical experience.

MATERIALS AND METHODS

We performed a retrospective study of medical records and X-ray data of 52 patients with fractures of the floor of the orbit, 18 to 68 years old, treated using transantral approach as described in the article. Titanium plates of special shape were used for orbital floor reconstruction.

RESULTS

In 94.2% of the cases, adequate restoration of the floor of the orbit was achieved. It led to regression of the ocular signs. In 4 patients, diplopia remained in extreme gaze positions, which did not require surgical correction. The failed cases were related to incorrect positioning of the plate or fixing screws. No inflammatory complications were observed.

CONCLUSION

Transantral access approach may be a technique of choice in treating patients with orbital floor fractures; it is safe, minimally traumatic, and effective in the early posttraumatic period when the injured area is located in the posterior parts of the floor of the orbit.

Transnasal prelacrimal approach to the inferior intraconal space: a feasibility study

BACKGROUND

Endonasal access to the inferomedial and inferolateral intraconal space via the orbital floor has not been reported. The primary purpose of this study was to assess the feasibility of accessing the inferior intraconal space through the orbital floor via a transnasal prelacrimal approach. Secondarily, it aims to highlight anatomical relationships of neurovascular structures in this space, as a requirement to prevent complications.

METHODS

Six cadaveric heads (12 sides) were dissected using a transnasal prelacrimal approach. The orbital floor, medial to the infraorbital canal, was removed and the periorbita opened to expose the inferior rectus muscle. The inferomedial and inferolateral intraconal space was accessed alongside the medial and lateral border of inferior rectus muscle, respectively. Various anatomical relationships of adjacent neurovascular structures were recorded, and the distances among the recti muscles and optic nerve were also measured.

RESULTS

The infraorbital nerve is located at the inferolateral aspect of inferior rectus muscle. In the inferomedial intraconal space, we identified the inferomedial muscular trunk of the ophthalmic artery, optic nerve, and branches of the oculomotor nerve; whereas the inferolateral intraconal space contained the inferolateral muscular trunk of ophthalmic artery, branches of the oculomotor and nasociliary nerve, and abducens nerve. Distances from the medial, inferior, and lateral recti muscles to the optic nerve were (mean ± standard deviation) 4.70 ± 1.18 mm, 5.60 ± 0.93 mm, and 7.98 ± 1.99 mm, respectively. Distances from the inferior rectus muscle to the inferior borders of medial and lateral recti muscles were 4.45 ± 1.23 mm and 8.77 ± 1.80 mm.

CONCLUSION

It is feasible to access the inferior intraconal space through the orbital floor via a transnasal prelacrimal approach. The access may be subdivided into inferomedial and inferolateral corridors according to the entry point at the medial or lateral border of the inferior rectus muscle. Neurovascular structures in the inferior intraconal space are visualized directly, which should enhance their preservation.

Three-Dimensional Printed Model and Transantral Endoscopy to Orbital Fracture Repair

Orbital fractures are high prevalent and result in several complications such as diplopia, muscular entrapment, visual impairment, and enophthalmos. The goal of orbital reconstruction is to restore orbital anatomy, volume, and globe symmetry. This case report aims to describe the use of transantral endoscopy and 3D printed model for treatment of an orbital floor fracture. A 54-year-old woman presented orbital floor fracture with diplopia and extraocular muscle entrapment. The surgical treatment was performed using a standard titanium mesh bended over 3D printed model, and transantral endoscopy to verify fracture extension and implant adaptation. The postoperative evaluation demonstrates correction of diplopia and ocular motility restriction. Computed tomography scan showed reestablishment of the orbital anatomy. The association of transantral endoscopy and 3D printed models is a feasible technique to improve orbital reconstruction.