Head and Neck Imaging

Mucocele

expansile lesion occurring within the cavity of a paranasal sinus, containing mucoid secretions and bordered by the sinus mucous membrane. These lesions cause pressure erosion and expansion of the bony sinus walls, and may displace adjacent structures. Mucoceles are most commonly seen in the frontal sinus, but may occur in any paranasal sinus. They originate from obstruction of the sinus ostium by inflammation, trauma (including surgery) or a benign or malignant tumour. The symptoms result from the mass itself and include frontal bossing, proptosis and nasal obstruction.

A mucocele appears on imaging as an expansile lesion in an airless sinus, with thinning and sometimes erosion of its bony walls (Fig.1). Sometimes a mucocele arises from a closed compartment of a paranasal sinus (see Caldwell Luc procedure). Inspissated mucoceles may show a high density on CT images. The signal characteristics on MRI are variable and depend on the degree of dehydration of the sinusal secretions (Fig.2). Apart from the lining membrane, no contrast enhancement is seen in a mucocele; the enhancement of the lining membrane is more pronounced in an infected mucocele (mucopyocele).

RH

To view high resolution images,
please register first.

Click  here to register.

Already registered? Enter your e-mail in the window below.
Re-register

Fig.1

Coronal CT image of sinonasal region. Large expansile ethmoid mucocele, displacing the orbital structures.
Mucocele, Fig.1
Mucocele, Fig.2 (a)
Mucocele, Fig.2 (b)