[Sinonasal cavities: CT imaging features of anatomical variants and surgical risk]

Anatomical variations of the sphenoid sinus and its adjacent structures: a review of existing literature

The sphenoid sinus, one of the posterior groups of sinuses, has long been regarded as a 'neglected sinus' due to the anatomical location, poor understanding and poor accessibility, till the advent of endoscopes and modern imaging techniques. Increasing knowledge and greater understanding of this sinus has permitted an evolution in surgical practices and boundaries. Various literatures of the past report a great variety of rates of pneumatization, rates of optic nerve protrusion and dehiscence, as well as internal carotid artery (ICA) protrusion and dehiscence. One similarity noted among these studies is that the rates vary according to the ethnicity of the patients. Recommendations have also been made along the way with regard to modified surgical techniques. This review aims to describe the pneumatization of sphenoid sinus and the topographical relation of the optic nerve and ICA in different populations.

An epidemiologic study of factors associated with nasal septum deviation by computed tomography scan: a cross sectional study

Background

Sinusitis is an inflammation of the paranasal sinuses that can be caused by anatomic variations of the nasal cavity and paranasal sinuses. In this study we aimed to find the relationship between sinusitis and septal deviation (SeD) and concha bullosa.

Methods

Two trained resident of ENT evaluated sinus CT scans of 463 cases presenting with nasal obstruction or chronic sinusitis symptoms from April 2011 to December 2011. CT scans were checked for the presence of conchae bullosa and the degree of septal deviation. The severity of sinusitis was evaluated according to the Lund Mackay criteria. The frequency of patients with different degrees of SeD and different grades of chronic sinusitis were studied.

Results

Of 463 cases, 47% had septal deviation. Concha bullosa was seen in 16.8% of the patients in the left side and 27.6% of them in the right side. There was no significant relationship between the presence of concha bullosa and the severity of sinusitis. Also the P value of analytical tests between the severity of sinusitis, osteomeatal involvement and the degree of septal deviation was not significant. Analysis of the relationship between the presence of SeD (either to right or left) and the severity of sinusitis in different sinuses revealed no significant P value.

Conclusions

By this study, the relationship between concha bullosa in osteomeatal complex and the severity of sinusitis was not cleared. No relationship was found between the severity of sinusitis, osteomeatal involvement and the degree of septal deviation. Also SeD (either to right or left) was not found to be associated with the severity of sinusitis in different sinuses.

Flying through congested airspaces: imaging of chronic rhinosinusitis

The complex regional anatomy of the nose and paranasal sinuses makes the interpretation of imaging studies of these structures intimidating to many radiologists. This paper aims to provide a key to interpretation by presenting a simplified approach to the functional anatomy of the paranasal sinuses and their most common (and most relevant) variants. This knowledge is basic for the full understanding of chronic rhinosinusitis and its computed tomography (CT) patterns. As fungal infections may be observed in the setting of chronic rhinosinusitis, these are also discussed. Chronic sinus inflammation produces bone changes, clearly depicted on CT images. Finally, clues to suspecting neoplastic lesions underlying inflammatory sinus conditions are provided.