How To: Reconstruction of Anterior Table Frontal Sinus Defects with Pericranial Flap and Titanium Mesh

INTRODUCTION

While a wide variety of frontal sinus pathologies can be addressed through endoscopic approaches, external approaches are required for some conditions such as certain fractures, tumors, encephaloceles, or select cases of recalcitrant frontal sinusitis. External frontal sinus approaches most commonly include trephination, osteoplastic flap, or cranialization. In each of these approaches, the anterior table of the frontal sinus is preserved, and, therefore, frontal contour is generally maintained.

In some situations, frontal sinus pathology necessitates removal of the anterior table (Rhinology. 2019;57:293-302). This technique can be quite disfiguring as it results in a significant frontal bone defect and resultant forehead depression. The anterior table defect poses a reconstructive challenge, and very few publications have described reconstructive options. For reconstruction, one must consider not only frontal contour restoration, but also the frontal sinus’s functionality. There are different biologic or synthetic materials available to restore frontal contour, and the decision on material type is based, in part, on whether one plans to obliterate the frontal sinus or maintain sinus function. To maintain frontal sinus function, surgeons must consider performing Draf IIA/B or III frontal sinusotomies to maintain sinus outflow patency and establish sinus wall linings that support mucosalization to ensure functional mucociliary clearance.

Various materials are available to repair the contour defect associated with anterior table resection, including autologous calvarial bone, titanium mesh, porous polyethylene, methyl methacrylate, and plastic polymers (The Frontal Sinus. New York: Springer; 2005:281-289). Pericranial flaps have been utilized for frontal sinus obliteration (Otolaryngol Head Neck Surg. 2006;135:413-416), but they have not been described for establishing the inner lining of the anterior wall of the frontal sinuses after anterior table resection. This article describes a viable technique for reconstructing large anterior table defects using a pericranial flap to reline the anterior sinus wall and a titanium mesh to restore frontal contour while preserving a functional frontal sinus.

To maintain frontal sinus function, surgeons must consider performing Draf IIA/B or III frontal sinusotomies to maintain sinus outflow patency and establish sinus wall linings that support mucosalization to ensure functional mucociliary clearance.

METHOD

A representative case is presented of a 42-year-old male patient with a grade 4 frontal sinus osteoma causing diplopia due to right orbital extension of the tumor. Institutional review board approval was obtained, and consent was obtained from the patient. First, bilateral endoscopic sinus surgery with Draf III frontal sinusotomy was performed. Next, a coronal incision was made to access the anterior table of the frontal sinus, and a pericranial flap was harvested and preserved for later use. The osteoma was completely resected, and the involved anterior table was removed, resulting in a 4 x 6 cm² anterior table defect.

Reconstruction commenced by first covering the anterior table defect with the pericranial flap to create a new anterior sinus wall inner lining. Next, a 0.3-mm thickness titanium mesh was contoured and placed over the pericranial flap and secured with screws to recreate the patient’s preoperative frontal contour. Silastic sheet stents were placed in the Draf III cavity to line both the anterior and posterior aspects of the cavity to prevent stenosis of the Draf III frontal outflow tract. Stents were removed one month postoperatively. Figure 1 shows diagrammatically on a sagittal computed tomography scan the layers of anterior table reconstruction, as well as the effect of the Draf III frontal sinusotomy in maintaining patency and function of the frontal sinus.

RESULTS

Eight months postoperatively, there was improved right eye position after tumor resection, and excellent frontal contouring after reconstruction. On nasal endoscopy, his frontal outflow tract was widely patent, all the walls of the frontal sinus appeared mucosalized, and there was no evidence of edema, crusting, or mucopurulence. The supporting video illustrates the key points of the operative technique used to reconstruct the patient’s large anterior table defect, as well as the aesthetic and functional outcomes .