A Giant Frontoethmoidal Ivory Osteoma Causing Cosmetic and Visual Problem: A Case Report

Abstract

Osteomas are slow growing fibro-osseous lesions. Very rare to occur in paranasal sinuses. Small osteomas don’t require any intervention. Giant osteomas may require surgical intervention due to its cosmetic and functional compromises. A 28 year old male presented with swelling over forehead and left orbit for more than 4 years. The swelling is around 6 × 5 cm with gross lateral and inferior deviation of left eyeball. Extradural fronto-ethmoidectomy was done with combined external and endoscopic approach. There was pearly white bony hard, fixed tumor mass seen infiltrating anterior and posterior table of frontal bone. All the tumors removed in piecemeals. Wait and watch policy is the usual treatment policy for small and asymptomatic osteomas. Combine external and endoscopic approach is the treatment of choice for giant frontoethmoid osteoma.

Introduction

Osteomas are slow growing benign fibro-oseous lesion. They are very rare to occur in paranasal sinuses, where they are most common in frontoethmoidal region. Majority of the tumors are asymptomatic because of average tumor size being less than 10 mm. Larger lesions upto 30 mm are very rare and may require surgical intervention depending on the location of the tumor. Giant osteomas those greater than 60 mm are extremely rare and obviously require surgical treatment [1]. External approach or a combinations of both external and endoscopic procedure are the treatment of choice for giant osteomas.

Case Report

A 28-year-old young male presented to ENT OPD with complaint of swelling over forehead and left orbit for 4 years. Swelling was insidious in onset, gradually progressive, painless, not associated with headache or any discharge from swelling. It was associated with deviation of left eye ball laterally and inferiorly (Fig 1). There was no history of diplopia, diminution of vision, watering of eyes, nasal obstruction or nasal discharge. There was history of application of ayurvedic medication over swelling and trauma 1 year ago which led to scar mark and discoloration of overlying skin.

Fig. 1.

Pre-op and post-op photograph showing the size and location of lesion

On examination – A single ill-defined diffuse swelling of size 6 X 5 cm was present over forehead, which was non tender, bony hard in consistency, fixed with overlying skin free and pinch able. It was extending 2 cm above the glabella superiorly, 1 cm below the root of nose inferiorly, till medial 1/3rd of right supraorbital ridge and middle of left supraorbital ridge (Fig). Swelling was pushing left eye ball anteriorly, inferiorly and laterally but vision and extra ocular movements of bilateral eyes was within normal limits.

On Diagnostic Nasal Endoscopy done—a single, hard, pale, non-tender mass was seen bulging from left frontal recess area pushing uncinate process laterally, middle turbinate medially and bulla ethmoidalis posteriorly (Fig. 2).

Fig. 2.

NCCT nose and PNS (0.6 mm cuts) showing hyperintense lesion arising from posterior wall of left frontoethmoidal sinus in coronal and axial plane

On CT scan of brain and paranasal sinuse (Fig) a well-defined lobulated lesion noted arising from posterior wall of left frontoethmoidal sinus measuring 6.3 X 4.3 X 5.6 cm (TR X AP X CC) causing expansion of frontal sinus along with thinning of its walls. Lesion is extending anterolaterally into lateral wall of left orbit and displacing left eye ball anteriorly and inferolaterally, medially extending into right frontal sinus and superomedial wall of right orbit, inferiorly abutting left middle turbinate and uncinate process. There is also extra axial compression of left frontal lobe. After proper evaluation he was posted for excision of frontoethmoidal osteoma by combined open and endoscopic approach.

• Brow skin incision was made and periosteum was elevated delineating the entire tumor. A 5 X 6 cm pearly white bony hard, fixed tumor mass seen infiltrating anterior and posterior table of frontal bone 2 cm above supraorbital ridge. Tumor was excised in piece meals with drill, bone gouge and mallet while preserving dura mater.

• Endoscopically there was 4 X 2 cm whitish pale, single, hard mass was seen bulging from left frontal recess area pushing uncinate process laterally, middle turbinate medially and bulla ethmoidalis posteriorly, it was delineated from surrounding structures and excised in piece meals.

• All the diseased frontal and ethmoid sinus were exenterated and cranialised using both external and endoscopic approach. Extradural fronto-ethmoidectomy was done keeping in mind not to breach the dura. Bony reconstruction was not done because of young patient and the preservation of dura (Fig) which helps in osteogenesis.

Discussion

Frontal osteomas are the most common paranasal sinus osteomas [2]. They are slow growing osteoblastic mesenchymal tumour. Most commonly seen in male in third and fourth decades of life. The growth is very slow at the rate of 0.44 to 6 mm per year. When enlarged they compress the surrounding structure causing cosmetic and functional problems. Our patient was having cosmetic and vision issue because of very large osteoma. Histologically there are three types of osteomas encountered: Ivory, mature and mixed type. In Ivory osteoma there are dense cortical bone hence called compact osteoma. Mature type contains cancellous bone and in mixed type there is both cortical and cancellous bone [3]. Surgical approach mainly based on the size and location of the tumor. Previously external approach was the standard for treatment of osteoma though it had obvious disadvantages like cosmesis, facial numbness and sometimes fracture. Now days combination of both osteoplastic flap and endoscopic approach is the treatment of choice to address the frontoethmoidal osteoma [4]. We performed a Draf type IIB along with external orbital approach which help us to visualize the medial part of the frontal sinus clearly. Recurrence is seen in 5 to 10% cases mostly because of incomplete removal of tumor [5].

Conclusion

Wait and watch policy is the usual treatment policy for small and asymptomatic osteomas. Giant osteomas that are more than 6 cms mostly warrant excision in view of cosmetic and functional disturbances. Combine external and endoscopic approach is the treatment of choice for giant frontoethmoid osteoma.

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Declarations

Conflict of interest

The authors claim no conflict of interest. Written informed consent had been sought from the patient regarding the surgery as well as publication for academic interest. The patient had been treated according to the standard protocol of treatment and in compliance with ethical standards.