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Abstract Objective: We sought to evaluate the added value of complementary functional imaging in the differential diagnosis of parapharyngeal space lesions, as well as the benefit of performing a structured evaluation of diagnostic cross-sectional examinations. Materials and Methods This was a retrospective study of 16 patients with parapharyngeal space lesions who were referred to our facility following a cross-sectional imaging study listing head and neck paraganglioma as a possible diagnosis. Each patient underwent somatostatin receptor scintigraphy with111In-pentetreotide (Octreoscan) prior to surgical resection of the lesion. In addition, the initial computed tomography (CT) or magnetic resonance imaging (MRI) scans were reviewed by two radiologists specializing in head and neck imaging, working independently, according to predefined diagnostic criteria. Results: Increased somatostatin receptor expression was observed in 14 of the 16 lesions evaluated. Histopathology of the surgical specimens showed that 11 of those 14 lesions were paragangliomas. Upon review, none of the three lesions for which there was a false-positive scintigraphy result (one intravascular meningioma and two schwannomas) were found to meet enough of the conventional imaging criteria for a diagnosis of paraganglioma. Conclusion: Structured analysis of imaging data increases the accuracy of the diagnosis of indeterminate parapharyngeal space lesions. Because of its high sensitivity, functional evaluation by somatostatin receptor scintigraphy should be considered a useful complementary tool for the detection of head and neck paraganglioma, provided that its limited specificity is taken into account.
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ABSTRACT To our knowledge, we report the first case of an extraconal orbital cystic schwannoma in Brazilian literature. The tumor grew slowly and progressively and was associated with minimal eccentric proptosis and diplopia. The radiologic study (orbital computed tomography) revealed a rounded, encapsulated, and extraconal cystic mass in the superior medial region of the right orbit in the supraorbital and supratrochlear nerve topography. An anterior orbitotomy with full excision of the tumor was performed, and the histopathology examination revealed that the tumor was a schwannoma. After the surgery, the patient experienced total remission of his symptoms.
RESUMO Os autores relatam o primeiro caso de schwannoma orbitário extraconal cístico relatado na literatura brasileira. O tumor apresentou aparecimento lento e progressivo, associado a proptose excêntrica e diplopia leves. O exame de imagem (tomografia computadorizada de órbita) revelou uma lesão nodular, arredondada, capsulada, extracônica, cística, na região súpero-medial de órbita direita, na topografia do nervo supraorbitário e supra-troclear. O paciente foi submetido à orbitotomia por via anterior, com exérese integral da tumoração. O exame histopatológico revelou o diagnóstico de schwannoma. Após a cirurgia, o paciente teve regressão total dos sintomas.