Guns n’ Noses: Endoscopic Removal of an Air-Gun Pellet Retained in the Frontal Sinus

Endoscopic Foreign Body Removal From the Frontal Sinus

A 16-year-old male was referred to our clinic for evaluation of a penetrating foreign body (FB) retained in the right frontal sinus. Five days earlier, he presented to a community emergency department after sustaining an injury to the right eyebrow from an air gun (Figure 1). Computed tomography (CT) scan revealed a metallic FB lodged in the right frontal sinus recess associated with a nondisplaced fracture of the frontal sinus anterior table (Figure 2).

Figure 1.

Small entrance of the air-gun pellet concealed within the right medial eyebrow.

Figure 2.

Computed tomography scan with coronal (left) and sagittal views (right) revealing foreign body (FB) within the right frontal sinus recess.

Physical examination demonstrated a 4-mm well-healing lesion at the right inferomedial eyebrow (Figure 1) associated with a palpable step off just medial to the wound. Both vision and extraocular muscle movements were intact. In-office nasal endoscopy with a 30° rigid nasal endoscope did not reveal evidence of trauma and no FB was visualized. There was no evidence of cerebrospinal fluid (CSF) leak.

Surgery was performed 9 days later. Under CT guidance, the right nasal cavity was visualized with a rigid 30° reverse sinus endoscope. After completing an anterior ethmoidectomy and frontal sinusotomy, the FB was visualized within the mucosa of the posterior frontal sinus recess (Figure 3A). Upon further dissection, the pellet was revealed and measured in situ (Figure 3B). The pellet was then removed successfully (Figure 3C). The patient was discharged the same day and was doing well at his 2-week follow-up.

Figure 3.

Endoscopic view of retained foreign body (FB; A: in situ, B: measured in situ, C: during retrieval).

Approximately 2% of penetrating head and neck traumas result in retained FBs in the sinuses or skull base. ¹ Air-gun injuries to the sinuses represent a small proportion of head and neck penetrating trauma. ¹ Approximately 60% of air-gun pellets are retained in the tissue that is first struck as they do not contain enough kinetic energy to penetrate through soft tissue and bone. ² Reported sequelae of retained FBs in the sinuses include sinocutaneous fistula, rhinolith formation, chronic pain, sinusitis, abscess formation, meningitis, epilepsy, and lead poisoning. ^{3 -6}

The management of this unique entity is dictated by the projectile’s trajectory and the involved structures. The early removal of sinus FBs is recommended to avoid detrimental sequelae and intracranial complications. ^3,5 The choice of therapy is influenced by the hemodynamic status of the patient, the FB location, and the extent of involved anatomy and critical structures such as the internal carotid artery, optic nerves, and ethmoidal arteries. ^2,7,8

Management of retained projectiles in the sinuses lacks robust guidelines given its rarity. Yarlagadda et al proposed a management algorithm, beginning with stabilizing the patient and imaging to determine the internal trajectory and the object’s exact location. ¹ The role of antibiotics for patients with penetrating head and neck trauma is not entirely clear. Local infection and abscess formation has been reported. ^2,9 As a result, prophylactic antibiotics against sinonasal flora are given in the acute trauma period and the perioperative period. ^1,2

Options for removal include open versus endoscopic approaches. The latter option has obvious cosmetic benefits by avoiding a facial scar. With the increasing availability and safety of endoscopic sinus surgery (ESS), this approach is favored by many for enhanced visualization and reduced morbidity compared to open approaches. ^1,9 The frontal sinus, however, presents unique challenges secondary to anatomic constraints, higher likelihood of FB embedded in bone, and an increased risk of CSF leak. ³ We opted for a limited Draf IIa approach, performing an anterior ethmoidectomy with dissection of all anterior fronto-ethmoidal cells within the frontal recess. Several creative complimentary techniques have also been demonstrated, including deployment of a urological basket, and even a magnet. ¹⁰ In select cases, external approaches to the frontal sinus can be used, such as a trephine or a Lynch incision. ¹¹ If CSF leak is suspected, intrathecal fluorescein may be utilized to localize the leak. ¹ Lastly, if there is any radiologic or intraoperative evidence of FB fragmentation, the sinuses should be thoroughly irrigated before procedure completion. ⁵

None of the previously documented cases of frontal sinus FBs specify where in the frontal sinus the objects were located. An object in the lateral wall may be considered less amenable to endoscopic retrieval than an object in the frontal recess. In this report, we demonstrate that the frontal sinus, like the other sinuses, is amenable to FB retrieval by an endoscopic approach, particularly if the object is embedded within the frontal sinus recess.