223 research outputs found

    Fungal rhinosinusitis

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    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 sinonasal malignancy

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    A combination of computed tomography (CT) and magnetic resonance imaging (MRI) is now established as the optimum assessment of sinonasal malignancy. CT and MRI are of particular value in assessing the skull base, orbit and pteryo-palatine and infratemporal fossae. Although MRI offers better differentiation of tumour from surrounding tissue and fluid, coronal CT is still required for the demonstration of bone erosion particularly in the region of the cribriform plate. Thus the extent of local tumour spread may be determined with a degree of accuracy in excess of 98 per cent. However, the final determinant of penetration of the dura and orbital periosteum requires per-operative frozen section assessment. A knowledge of the tissue characteristics and site of origin can be of value in distinguishing some of the commoner sinonasal malignancies such as squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, olfactory neuroblastoma and chondrosarcoma. Imaging, particularly MRI also plays an important role in the post-therapeutic follow-up of patients, indicating areas of residual or recurrent disease, defining suspicious areas for biopsy. Post-operative surveillance is best achieved with three planar T1-weighted MRI, with, and without, gadolinium and axial T2-weighted sequences. The subtraction of the T1 pre- and post gadolinium T1 sequences can be of particular value in delineating recurrence

    Optimum imaging for inverted papilloma

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    Inverted papilloma is the most common benign tumour of the nose and paranasal sinuses, and usually arises in the lateral wall of the nasal cavity and the middle meatus. The diagnosis is suggested on computed tomography (CT) when there is a mass continuous from the middle meatus into the adjacent maxillary antrum, through an expanded maxillary ostium. The mass may contain areas of high density or calcification, and there may be sclerosis of the wall of the affected sinus. The main advantage of magnetic resonance imaging (MRI) is in defining the extent of the tumour, and in differentiating it from adjacent inflammatory tissue, but there are no certain signal intensity or enhancement characteristics to help differentiate inverted papilloma from sinus malignancy. In the differential diagnosis, antro-choanal polyp, malignant sinus tumours and chronic rhinosinusitis and fungal disease need to be excluded. The combination of bone deformity and sclerosis with the typical antro-meatal mass suggests a slow-growing tumour such as inverted papilloma

    Optimum imaging and diagnosis of cerebrospinal fluid rhinorrhoea

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    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

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    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

    Optimum imaging for mucoceles

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    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

    QUARTIERE DELLA CULTURA MANN UNINA E INVITALIA PER LA RIGENERAZIONE URBANA

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    L’attività di terza missione universitaria e di impegno del MANN sul territorio insieme alle azioni di finanziamento per lo sviluppo dell’industria culturale da parte di INVITALIA che gestisce fondi di provenienza europea, hanno consentito di far convergere una serie di azioni mirate su una parte della città ricca di identità, ma che versa in un profondo degrado per consentirne la crescita e la rigenerazione urbana grazie all’attività sinergica delle suddette istituzioni. L’impatto economico, sociale, culturale che il MANN sta determinando sul quartiere nel quale è inserito e oltre i confini dello stesso è oggetto di valutazione da parte di un team universitario della Federico II che ultimerà i lavori di indagine e verifica nel 2022, tuttavia sono già visibili e registrabili alcuni elementi di miglioramento e sviluppo del territorio. Basti far cenno all’accresciuta partecipazione dei pubblici, italiani e stranieri che popolano quotidianamente le sale del MANN; oppure agli esercizi commerciali di enogastronomia di eccellenza che hanno stabilito proprie sedi nei pressi del museo in ragione dell’accresciuto numero dei visitatori; oppure ancora al c.d. audience development che in una parola testimonia come la collettività cittadina si sia riappropriata del sito e partecipi con target di tutte le età alla vita quotidiana dell’istituto, con laboratori didattici, tirocini universitari, visite tematiche di scuole di ogni grado, nonché eventi culturali di molteplici istituzioni, enti, e festival

    Oxygen reduction in acid media: effect of iron substitution by cobalt on heat-treated naphthalocyanine impregnations supported on preselected carbon blacks

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    FeNPc(1.2) impregnations were investigated at various loadings using a rotating-disk electrode, voltammetry and X-ray photoelectron spectroscopy (XPS) techniques. Optimal activity takes place at monolayer coverage, and major demetallation occurs after prolonged exposure to acid solution. The substitution of Fe by Co enables the electrochemical performances to reach those presented by 10% Pt on Vulcan and stops the demetallation process. The application of fast atomic bombardment secondary ion mass spectrometry (FABS) together with XPS sheds light on the detrimental role of some electrophilic groups attached to the carbon black-catalyst interface

    Oxygen reduction in acid media on supported iron naphthalocyanine: Effect of isomer configuration and pyrolysis

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    O2 reduction in H2SO4 medium has been investigated on FeNPc impregnations on Norit BrX by the rotating disk electrode technique. Important differences in activity and stability were found between the 1,2- and 2,3-FeNPc isomers (pyrolysed or not). XPS analyses show, for the most inactive sample, strong demetallation and nitrogen losses. This phenomenon can be attributed to the differences in flexibility between the FeNPc isomers, which influences their stabilization on the substrate

    Oxygen reduction in acid media: influence of the heat treatment on the FeNPc(1–20 isomer mixture impregnated on carbon blacks and active charcoals

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    Oxygen reduction with the aid of a number of FeNPc(1–2) impregnated carbon supports in sulphuric acid solutions has been investigated.\ud \ud Loading of the carbon samples amounted to about 10 wt.%. After a 10 day stay in the aerated solutions the samples were investigated with rotating disk electrode and X-ray photoelectron spectroscopy techniques. The most active and stable samples correspond to mono- or submonolayers of FeNPc deposited on high dibutylphthalate adsorption carbon blacks. Comparison with data obtained previously on Norit BrX impregnations emphasizes the rôle of the electron density on the inner nitrogen atoms rather than that on the iron centres
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