**11. Frontal sinus obliteration**

Obliteration of the sinus is performed by the use of various materials, such as fat, muscle, bone or hydroxyapatite. Meticulous removal of the entire mucosal lining is the most important element in successful frontal sinus obliteration. Permanent occlusion of frontal recess and complete obliteration of the sinus are essential in avoiding recurrence of infections and preventing possible complications [22].

Indications for frontal sinus obliteration include failure of endoscopic approaches to ade‐ quately communicate frontal sinus with the nasal cavity, loss of anterior bony table of the frontal sinus, severe fractures of floor of the frontal sinus and benign tumors [23]. The standard bicoronal incision is performed through the galea. The pericranium is incised as far posteriorly as possible, and a subperiosteal dissection is carried up to the supraorbital rim, preserving the supratrochlear and supraorbital neurovascular bundles. The frontal sinus is outlined. The anterior bony table is then removed. Sinus mucosa is meticulously exenterated with a perios‐ teal elevator, and the interior of the sinus is carefully drilled with a medium-sized diamond burr. Nasofrontal ducts are then plugged with temporoparietal fascia and muscle. Obliteration of the frontal sinus is then performed with the previously mentioned materials (Figure 8).The anterior table plate is then replaced and plated.

**obliteration. Right: The frontal sinus is obliterated with muscle. Figure 8.** Left: Part of the temporalis muscle is excised for frontal sinus obliteration. Right: The frontal sinus is obliter‐ ated with muscle.

of the frontal sinus, with involvement of both the anterior and the posterior

**Figure 8. Left: Part of the temporalis muscle is excised for frontal sinus**

#### **FRONTAL SINUS CRANIALIZATION** The primary indication for cranializing the frontal sinus is severe traumatic injury **12. Frontal sinus cranialization**

long-term tenting (Figure 7) and mucosal flaps. However, in unilateral and bilateral nasofron‐ tal duct injuries, obliteration of the frontal sinus is preferred. The procedure involves the removal of all mucous membrane and the inner cortical lining of the sinus and obliteration of the nasofrontal duct and the sinus. Mucocele formation is possible if the mucosa is inade‐

**Figure 7.** The frontal sinus approached with an open sky incision for reconstruction of the naso-frontal duct via stent‐

Extremely high-velocity injury may result in comminution of the posterior table with dural tearing. If this happens, the intracranial contents become in direct communication with nasal mucosa. In this setting, management principles are careful mucosal removal, nasofrontal duct occlusion and cranialization of the frontal sinus. The neurosurgeon repairs any associated intracranial injuries. The frontal lobes are then allowed to expand into the space where the

Obliteration of the sinus is performed by the use of various materials, such as fat, muscle, bone or hydroxyapatite. Meticulous removal of the entire mucosal lining is the most important element in successful frontal sinus obliteration. Permanent occlusion of frontal recess and complete obliteration of the sinus are essential in avoiding recurrence of infections and

quately removed during obliteration.

478 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

ing technique

**10. Posterior table fracture**

frontal sinus once existed.

**11. Frontal sinus obliteration**

preventing possible complications [22].

tables. Obliteration of the frontal sinus is an option in some cases but the loss of a substantial portion of the posterior table bone places the survival of a fat graft necessary for obliteration in doubt and makes cranialization more appropriate [24]. The presence of cerebrospinal fluid (CSF) rhinorrhea, the need for neurosurgical intervention, or simply an expectation of inadequate follow‐up are all factors that may guide one towards cranialization. The approach to frontal sinus is performed via a bicoronal incision. Once access to the posterior table has been achieved, it is removed carefully in pieces with a rongeur. Larger pieces are saved for possible use replacing defects in the anterior table. Small overhangs at the periphery of the sinus should be smoothed completely, using a cutting burr. The The primary indication for cranializing the frontal sinus is severe traumatic injury of the frontal sinus, with involvement of both the anterior and the posterior tables. Obliteration of the frontal sinus is an option in some cases but the loss of a substantial portion of the posterior table bone places the survival of a fat graft necessary for obliteration in doubt and makes cranialization more appropriate [24]. The presence of cerebrospinal fluid (CSF) rhinorrhea, the need for neurosurgical intervention, or simply an expectation of inadequate follow-up are all factors that may guide one towards cranialization. The approach to frontal sinus is performed via a bicoronal incision. Once access to the posterior table has been achieved, it is removed carefully in pieces with a rongeur. Larger pieces are saved for possible use replacing defects in the anterior table. Small overhangs at the periphery of the sinus should be smoothed completely, using a cutting burr. The end result of the removal of the posterior table bone is the elimination

end result of the removal of the posterior table bone is the elimination of the frontal sinus as a distinct space. This space is now encompassed within a new,

Once the entire posterior table has been removed, all sinus mucosa is taken out. This is done first bluntly, with a hemostat or forceps. Remnant mucosa is then eliminated using a diamond burr. Establishing a secure barrier between the cranial fossa and the nose is necessary to prevent CSF leak, meningitis, and ascending regrowth of the sinonasal mucosa. After the neurosurgery team has accomplished a watertight dural repair (**Figure 9**), and the bone and mucosa removal are complete, the most superior aspects of the frontal duct mucosa are elevated from the underlying bone and inverted downwards, toward the nose. The superior

larger anterior cranial fossa, with the anterior table as its anterior limit.

portions of the ducts are then packed off using bone, fascia, and muscle.

of the frontal sinus as a distinct space. This space is now encompassed within a new, larger anterior cranial fossa, with the anterior table as its anterior limit.

Once the entire posterior table has been removed, all sinus mucosa is taken out. This is done first bluntly, with a hemostat or forceps. Remnant mucosa is then eliminated using a diamond burr. Establishing a secure barrier between the cranial fossa and the nose is necessary to prevent CSF leak, meningitis, and ascending regrowth of the sinonasal mucosa. After the neurosurgery team has accomplished a watertight dural repair (Figure 9), and the bone and mucosa removal are complete, the most superior aspects of the frontal duct mucosa are elevated from the underlying bone and inverted downwards, toward the nose. The superior portions of the ducts are then packed off using bone, fascia, and muscle.

Abdominal fat harvested through a small paraumbilical incision is filled in around the dural closure, occupying intracranial dead space. Repair of the anterior table is essential for both structural and cosmetic concerns. Anatomic reductions are carried out with fixation.

**Figure 9.** Water tight closure of the dura for prevention of CSF leakage
