2017-18 HSC Section 4 Green Book

Treatment strategies for frontal sinus anterior table fractures and contour deformities

females exhibit a smoother and more sloped forehead. Within these guidelines, ethnic differences and individual variations do exist. Drastic deviations from these ideal pa- rameters result in a unpleasant appearance, as represented by an abnormally sloping or protruding forehead. 6 The nasofrontal angle is intimately associated with nasal appearance, and a change in the nasofrontal angle may affect the perception of nasal appearance. A sloped fore- head with an obtuse nasofrontal angle exaggerates nasal length and projection. Conversely, a protruding forehead with a smaller nasofrontal angle diminishes the perceived nasal length 7 ( Figure 3 ). The frontal sinus has an inherent convexity, as described previously. When traumatized, the convexity is flattened and a concavity is formed, not only affecting the appear- ance of the forehead region 4 but also potentially altering the perception of nasal appearance. Considerable force is required to fracture the frontal sinus, particularly in the region of the frontal bar. 4,8 High-velocity impact from motor vehicle collisions remains the most common etiology of frontal sinus fractures, followed by interpersonal violence and sporting injuries. 2,9 e 12 In gen- eral, the higher the velocity of impact, the more likely that both anterior and posterior tables will be fractured. 3 Iso- lated posterior table fractures are much less common. 13 Due to the high-energy impacts required to fracture the frontal sinus, patients suffering from frontal sinus fractures often sustain other concomitant injuries. Unless the point of impact strikes directly over the frontal sinus, frontal sinus fractures are generally associated with other concomitant soft tissue injury and fractures 2,3 up to 75% of the time. 12 Pathophysiology

further evaluation of the frontal region until after the pa- tient has been stabilized and more critical injuries have been addressed. Assessment of frontal sinus fractures should always entail a thorough history and physical examination. Lacer- ations in the frontal region are identified and examined carefully for any osseous discontinuity or palpable step-off. The patient should also be examined for cerebrospinal fluid rhinorrhea and orbital injury. Although a thorough physical examination is always important, hematoma or soft tissue edema can obscure a frontal sinus fracture during initial inspection. Therefore, high-resolution computed tomography (CT) with thin slices is now considered the gold standard for evaluation of frontal sinus trauma. CT scanning permits optimal assess- ment of the integrity of both anterior and posterior tables of the frontal sinus, as well as NFOT involvement. Axial imaging provides information regarding fracture location, size, and depth, whereas coronal and sagittal imaging may shed light on NFOT injury. 14 Frontal sinus fractures may involve the anterior table, posterior table or both, with or without involvement of the NFOT. Furthermore, these fractures can be classified as either non-displaced or displaced ( > 2 mm or > 1 table- width displacement), and simple versus comminuted ( Figure 4 ). As with any form of maxillofacial fracture repair, the goal of frontal sinus fracture repair is to restore form and function and to prevent delayed complications. In general, repair of displaced anterior table fractures is largely for cosmetic reasons; repair of displaced posterior table frac- tures is to prevent intracranial complications (e.g., cere- brospinal fluid leak, meningitis, or encephalitis); and repair of NFOT is to prevent delayed complication (e.g. frontal sinusitis, mucocele, or pyocele). The repair of posterior table fractures and NFOT injuries is beyond the scope of this review. Goals of surgical repair

Initial assessment

Initial assessment and management of airway, breathing, and circulation are essential. At times, this means deferring

Effect of a sloping or protruding forehead on nasal appearance.

Figure 3

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