Abstract
BACKGROUND: Osteomas are the most common benign tumors of the sinonasal region. Often asymptomatic, they are frequently discovered incidentally during imaging studies conducted for unrelated conditions. Osteomas typically range in size from 2 to 30 mm; those larger than 30 mm or weighing more than 110 g are classified as "big" or "giant" osteomas. Giant osteomas of the paranasal sinuses are extremely rare and can extend into the intraorbital or cerebral space, leading to significant complications. When osteomas become symptomatic, the standard treatment is surgical intervention to alleviate associated issues and prevent further progression. CASE PRESENTATION: This report discusses a case of a giant fronto-ethmoidal osteoma (45 × 42 mm) with intracranial and orbital extension, focusing on the clinical presentation, diagnostic process, and surgical management. We present the case of a 30-year-old Black female patient from Addis Ababa, Ethiopia, with a fronto-ethmoidal osteoma causing compression of the ocular globe and the left frontal lobe. Given the intracranial extension, a combined surgical team consisting of an ENT surgeon and a neurosurgeon was assembled to address the case. The surgery was performed via an external and lateral rhinotomy with a Lynch extension approach, aiming for complete resection of the osteoma originating from the frontal sinus and extending into the orbit and intracranial space. CONCLUSION: Giant sinonasal osteomas are rare tumors. The primary goal of treatment is to completely remove the tumor using a combined endoscopic and external approach. Postoperative morbidity varies depending on the surgical technique used, and there is a risk of recurrence if the tumor is not entirely excised.