FRONTAL SINUS CHOLESTEATOMA

Ankara Üniversitesi Tıp Fakültesi KBB Anabilim Dalı, Ankara, Türkiye Frontal sinus cholesteatomas are rare lesions that are hard to differentiate, clinically and radiographically, from inflammatory (i.e. mucocele, pyocele, mucus retention cysts) and neoplastic (i.e. fibroma, osteoma, malignant tumors) diseases of the paranasal sinuses. In this study, two cases of frontal sinus cholesteatoma are presented, stressing their differential diagnosis from other paranasal sinus lesions according to their radiographic appearances and the surgical treatment. Frontal sinus cholesteatomas can be differentiated from other neoplasms by their sharp circumferential bony erosion on radiographs and lack of contrast enhancement on computed tomography (CT) scanning; however, mucoceles and cholesterol granulomas cannot be ruled out by a CT scan. Cholesterol granulomas, one of the most common lesions that need to be differentiated from cholesteatomas, show hyperintense signals, in contrast to the hypointense signals of cholesteatomas on T1 weighted images on magnetic resonance imaging (MRI). It’s yet not possible to differentiate cholesteatomas from mucoceles with current imaging methods, including MRI. Although rare, the diagnosis of frontal sinus cholesteatoma should also be considered in patients suspected to have a frontal sinus mucocele. Since the extent of surgery needs to be wider in cholesteatomas, necessary precautions should be considered in the preoperative preparation of these patients. Surgery is the sole treatment option for frontal sinus cholesteatomas and the basic principle of surgery is to remove the cholesteatoma matrix in continuity, in order to prevent recurrence. Keywords : frontal sinus cholesteatoma, paranasal sinuses, diagnosis, treatment, surgery