Imaging for endoscopic sinus surgery in adults

Computerized tomography (CT) offers the gold standard in terms of imaging the extent of disease and the fine detailed anatomy, both pre-requisites to the safe practice of endoscopic sinus surgery. Neither plain X-rays nor magnetic resonance imaging (MRI) offer optimal information in this respect. A variety of protocols minimizing radiation dose to the lens whilst providing high quality images are presented together with a menu of anatomical features that require careful evaluation pre-operatively

Topic in dialogue: prosodic and syntactic features

In this paper we investigate the relationship between phonetic phrasing, tonal pattern and phrase structure in left peripherical sentence topic. Our corpus consists of three task-oriented Italian dialogues. The results of prosodic analysis show that topics are usually associated to the highest pitch values in the Tone Unit, regardless to their actual syntactic position. Syntactic analysis shows that, while topic phrase structure is rather variable, topic function is quite stable, i.e., topics have mostly circumstantial-locative function, and less frequently subject function. Finally, phonetic phrasing, prominence placement and phrase structure shows clearly regular relationships

Fungal rhinosinusitis

Fungal infections in both their invasive and non-invasive forms can prove difficult to diagnose. The often characteristic appearances on imaging are of great assistance. CT is the primary imaging modality and is probably more accurate than MRI in diagnostic specificity and determining the extent of bone erosion. However this may require a modified scanning technique to adequately demonstrate the typical soft tissue density variations of fungi. MRI should be used to supplement CT when intra-cranial or intra-orbital extension is suspected

Optimum imaging for mucoceles

A mucocele is an epithelial lined mucus-containing sac completely filling a paranasal sinus and capable of expansion. They are relatively unusual, occurring most frequently in the fronto-ethmoidal region. The imaging features on plain X-ray, computerized tomography and magnetic resonance imaging are relatively characteristic allowing distinction of the lesion from other pathologies in this area although the mucoceles may occur in association with other pathologies such as nasal polyposis and neoplasia

Optimum imaging and diagnosis of cerebrospinal fluid rhinorrhoea

Imaging is an important component in the investigation of unilateral watery rhinorrhoea suspicious of cerebrospinal fluid (CSF). Whilst the demonstration of the presence of beta 2 transferrin confirms that CSF is present it may prove difficult to demonstrate the exact site of origin. Fine detail coronal computed tomography (CT) with sections of 1-2 mm thickness through the anterior skull base may show small dehiscences and fractures. The commonest site for congenital dehiscences is the cribriform niche adjacent to the vertical attachment of the middle turbinate anteriorly and the superior and lateral walls of the sphenoid posteriorly. In the presence of frequent or constant CSF rhinorrhoea a CT cisternogram can be helpful in defining the exact site of the leak. Magnetic resonance imaging (MRI) is reserved for defining the nature of soft tissue Le. inflammatory tissue, meningoencephalocele or tumour. Finally, per-operative intrathecal fluorescein is helpful when imaging does not prove positive. A management algorithm for CSF rhinorrhoea is presented

Imaging for juvenile angiofibroma

Juvenile angiofibroma presents characteristic imaging signs, many of which allow diagnosis and accurate estimation of extent without recourse to the dangers of biopsy. The diagnosis by computed tomography (CT) is based upon the site of origin of the lesion in the pterygopalatine fossa. There are two constant features: (1) a mass in the posterior nasal cavity and pterygopalatine fossa; (2) erosion of bone behind the sphenopalatine foramen with extension to the upper medial pterygoid plate. Good bone imaging on CT is essential to show invasion of the cancellous bone of the sphenoid. This is the main predictor of recurrence: the deeper the extension, the larger the potential tumour remnant likely to be left following surgery. The characteristic features on magnetic resonance imaging (MRI) are due to the high vascularity of the tumour causing signal voids and strong post-contrast enhancement. MRI shows the pre-operative soft tissue extent of angiofibroma optimally, but its more important application is to provide post-operative surveillance: to show any residual or recurrent tumour, record tumour growth or natural involution and monitor the effects of radiotherapy