RESUMEN
AIM: To analyse the maximum standardised uptake value (SUVmax) ratio between tonsils in patients with and without tonsillar carcinoma to determine useful diagnostic thresholds. MATERIALS AND METHODS: Positron-emission tomography (PET)/computed tomography (CT) examinations of patients with suspected head and neck squamous cell carcinoma (SCC) and controls from April 2013 to September 2016 were reviewed retrospectively. Tonsillar SUVmax ratios (ipsilateral/contralateral for malignant tonsils, maximum/minimum for patients without [controls]) were calculated and used to construct a receiver operating characteristic (ROC) curve. RESULTS: Twenty-five patients had tonsillar carcinoma (mean SUVmax ratio of 2, range 0.89-5.4) and 86 patients acted as controls (mean SUVmax ratio of 1.1, range 1-1.5). Using the ROC, the most accurate SUVmax ratio for identifying malignancy was >1.2 (77% sensitivity, 86% specificity). A potentially more clinically useful SUVmax ratio is ≥1.6 with 62% sensitivity and 100% specificity. CONCLUSION: An SUVmax ratio between tonsils of ≥1.6 is highly suspicious for SCC and could be used to direct site of biopsy. Some malignant tonsils had normal FDG uptake; therefore, PET/CT should not be used to exclude tonsillar cancer. Minor asymmetrical uptake is frequently seen in non-malignant tonsils and does not necessarily require further investigation. Due to the single centre nature of this study and the recognised variation in SUV measurements between PET scans, other centres may need to develop their own cut-offs.
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Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Tonsila Palatina/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
Dizziness is a frequent indication for neuroimaging within the outpatient and emergency setting with variable diagnostic yield. The majority of persistent, recurrent, and isolated dizziness can be managed clinically. However, it may be difficult to distinguish a benign peripheral aetiology from a central cause, particularly in the emergency setting. We review the relevant anatomy, differential diagnosis, and key imaging features of central and peripheral causes of dizziness, as well as the literature for the diagnostic yield in acute and outpatient settings.
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Enfermedades del Sistema Nervioso Central/diagnóstico , Trastornos Cerebrovasculares/diagnóstico , Diagnóstico por Imagen/métodos , Mareo/diagnóstico , Cardiopatías/diagnóstico , Enfermedades del Laberinto/diagnóstico , Angiografía/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Sistema Cardiovascular/diagnóstico por imagen , Sistema Cardiovascular/patología , Sistema Nervioso Central/diagnóstico por imagen , Sistema Nervioso Central/patología , Enfermedades del Sistema Nervioso Central/complicaciones , Trastornos Cerebrovasculares/complicaciones , Mareo/etiología , Oído Interno/diagnóstico por imagen , Oído Interno/patología , Cardiopatías/complicaciones , Humanos , Enfermedades del Laberinto/complicaciones , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodosRESUMEN
The most frequent lesion identified at the cerebellopontine angle cistern and internal auditory meatus (IAM) is the vestibular schwannoma. Radiological features, the role of imaging in screening and follow-up, therapeutic approaches and appearances following treatment will be discussed. Other cerebellopontine angle lesions will be illustrated and an algorithm presented to help in the imaging differential diagnosis. Whilst lesions other than vestibular schwannomas are rarely isolated to the IAM, the key clinical and radiological features that should raise the possibility of alternative neoplastic and inflammatory diseases will be highlighted.
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Ángulo Pontocerebeloso/diagnóstico por imagen , Neuroma Acústico/diagnóstico por imagen , Algoritmos , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos XRESUMEN
AIM: To assess the accuracy of ultrasound in characterizing benign and malignant parotid lesions and to review their sonographic features. MATERIALS AND METHODS: A retrospective analysis of 220 ultrasound examinations was undertaken in 220 patients who presented with palpable parotid lesions over an 11-year period and correlated with the clinico-histopathological findings. The original sonographic diagnosis was compared to the final histopathology and lesions characterized using previously established sonographic criteria. RESULTS: Histopathology results were available for all patients. Two hundred and one patients had focal lesions: 29 carcinomas, 21 lymphomata and 151 benign lesions (including 69 pleomorphic adenomas and 54 Warthin's tumours); 19 patients did not have focal lesions. The initial ultrasound report was indeterminate in 25/201 focal lesions. In the remaining 176 lesions, the sensitivity, specificity, and diagnostic accuracy for malignancy of ultrasound was 91, 93, and 93%, respectively. There were four false-negatives and nine false-positives with a crossover of apparently benign and malignant features. Pleomorphic adenomas and Warthin's tumours were poorly differentiated using ultrasound. Additional impalpable parotid lesions or adenopathy were detected in 44 patients using ultrasound. CONCLUSION: Ultrasound is a valuable adjunct to clinical examination, accurately differentiating benign from malignant lesions and diagnosing non-focal disease. There is an overlap in features of pleomorphic adenomas and Warthin's tumours and of some benign and malignant lesions. Diagnostic ultrasound should be combined with needle biopsy in most patients to maximize diagnostic yield.
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Enfermedades de las Parótidas/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Enfermedades de las Parótidas/patología , Estudios Retrospectivos , Sensibilidad y Especificidad , Ultrasonografía , Adulto JovenRESUMEN
The use of ultrasound-guided wire localisation of lesions is not well described in the orthopaedic literature. We describe a case of an impalpable schwannoma of the femoral nerve and another of sacroiliitis with an associated pelvic abscess. In both, surgical localisation was difficult. Peri-operative ultrasound-guided wire localisation was used to guide surgery and minimise tissue damage, thereby optimising the results and recovery of the patient.