Endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach for resection of frontoethmoidal osteoma causing tension pneumocephalus

Abstract

Tension pneumocephalus is an unusual, potentially life-threatening complication of frontal fossa tumors. We present an uncommon case of a frontoethmoidal osteoma causing a tension pneumocephalus and neurological deterioration prompting a combined endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach for resection. A 68-year-old man presented with a 1-week history of worsening headache, slowness of speech, and increasing confusion. Standard computed tomography scan revealed a marked tension pneumocephalus with ventricular air and 1-cm midline shift to the right. Further studies showed a calcified left ethmoid mass and a left anterior cranial-base defect. A team composed of neurosurgery and otolaryngology performed a combined endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach to resect a large frontoethmoid bony tumor. No abscess or mucocele was identified. The skull base defect was repaired with the aid of a transnasal endoscopy, a titanium mesh, and a pedunculated pericranial flap. Postoperatively, the pneumocephalus and the patient's symptoms completely resolved. Pathology was consistent with a benign osteoma. This is an uncommon case of a frontoethmoidal osteoma associated with tension pneumocephalus. Recognition of this entity and timely diagnosis and treatment, consisting of an endonasal ethmoidectomy and a bifrontal craniotomy with craniofacial approach, may prevent potential life-threatening complications.

Keywords: Bifrontal craniotomy; craniofacial; endonasal ethmoidectomy; frontoethmoidal osteoma; tension pneumocephalus.

Figure 1

(A) Lateral skull radiograph shows the air in the lateral ventricle (large arrow) and beneath the frontal lobe (curved arrow). There is also a small mass in the posterior ethmoid sinus (small arrow). (B) Computed tomography (CT) image shows a mass (arrow) 3 cm × 1.5 cm in the left middle and posterior ethmoid sinus with a focus of dense calcification. (C) On a CT image through the base of frontal lobes (arrow), the upper part of the mass is contiguous with the pneumocephalus (curved arrow). (D) Enhanced coronal magnetic resonance imaging shows the paranasal sinus mass (arrow) and its relationship to the frontal air (curved arrow).

Figure 2

(A) Intraoperative endoscopic image of the ethmoid sinus lesion. (B) Osteoma-bone interface. The interface between the osteoma (top) and normal bone (bottom) is indicated by the white arrow (hematoxylin and eosin [H & E] stain, × 100). (C) Osteoma. The tumor is located directly beneath the sinus epithelium (white arrow) (H & E stain, × 100). (D) Osteoma. Spicules of bone are seen within a meshwork of loose, fibrous tissue. The bone is rimmed by osteoblasts (white arrows) and an occasional, multinucleated osteoclast (black arrow) (H & E stain, × 400).