Endoscopic Endonasal Management of an Ethmoidal Osteoma with Orbital Extension

AbstractOsteomas are the most common benign tumors of nose and paranasal sinuses. Endonasal endoscopic surgery began to find its place in fronto-ethmoidal osteoma surgery instead of open procedures. In this paper, an ethmoidal osteoma case with orbital extension totally resected with endonasal endoscopic approach was reported. The patient rapidly recovered postoperatively without any morbidity and with great cosmetic result. There was no tumor recurrence during 7-months of follow up. When compared to the previously used management modalities, endonasal endoscopic surgery for skull base lesions including fronto-ethmoid osteomas is a newly developing technique of the last century. Clinical experiences show that, in trained hands, this is a safe and effective procedure, by which a radical tumor excision can be possible regardless to its extension in appropriate cases.

Keywords:endoscopic endonasal, fronto-ethmoidal, orbital, osteoma

Introduction:Osteomas are known to be the most common benign tumors of the nose and paranasal sinuses1. In the order of frequency these tumors tend to appear in frontal, ethmoid, maxillary and sphenoid sinuses2. These rare osteogenic neoplasms have a relatively slow growing rate that causes non-specific and tardy initial syptoms such as headache and facial pain1. Although it is a rare event, depending on the tumors extension facial deformity, rhinorrhea, anosmia, sinusitis and ocular signs and sympoms may occur. For symptomatic lesions the choice of treatment is still surgery however, the surgical approach is controversial3. Although to date, open procedures have being used for large osteoma removal, by the recent technical developments endonasal endoscopic approach began to find its place in fronto-ethmoidal osteoma surgery which enables a closer and direct visualization4, 5. In this paper, an ethmoidal osteoma case with orbital extension, totally resected with endonasal endoscopic approach was reported.

Case Report:A 19-years-old female patient presented to our clinic with a 2 months history of progressive right eye and facial pain, headache and diplopia. Clinical examination showed right proptosis and lateral gaze diplopia without any cognitive disorders. The patient was referred to the ophthalmology clinic. Visaual acuity was found to be unaffected but, perimetry test showed a minimal temporal loss in right visual field. Radiological studies revealed an irregular shaped, 25x22mm large bony mass in ethmoid sinus with right orbital extension, causing a slight optic nerve diversion (Figure 1). Intrasellar region and pituitary gland was free of tumoral invasion. The patient was chosen to undergo endonasal endoscopic surgery with extended approach for a better exposure and maneuverability. With a binostril approach and right medial turbinate excision, sphenoid sinus roof and right maxillary sinus was reached. At this step, a bony neoplasm originating from right ethmoidal sinus, destructing the inferomedial wall of the orbit and growing through periorbita without intracranial infiltration was exposed (Figure 2). The tumor was excised with pure endonasal endoscopic approach using a high speed surgical drill (Midas Rex® Legend® Stylus®, Medtronic Inc., Fridley, Minnesota / USA) with an appropriate angled bore attachment for endoscopic surgery and a diamond ball tool. Total removal of the tumor was followed by a multilayer reconstruction to the inferomedial wall of the orbit without any complications (Figure 3). For a multilayer complete closure a fascia lata autograft prepared from a superolateral thigh incision was applied under the orbital bone defect to prevent periorbital displacement. Then the graft was bolstered with absorbable fibrillar hemostat (Surgicel®, Ethicon, Johnson & Johnson, Blue Ash, Cincinnati, Ohio / USA) and autologous fibrin sealant (Vivostat®, Vivostat A/S, Borupvang 2 DK-3450, Alleroed / Denmark) respecteively. During the procedure rigid endoscopes with zero and 30-degree lenses were used according to different steps of the operation. All procedures were performed with informed consent of the patient. The patient rapidly recovered after the surgery and discharged in the 4th postoperative day. There was no tumor recurrence detected during 7 months of follow up.