4D-CT facilitates focused parathyroidectomy in patients with primary hyperparathyroidism by maintaining a high negative-predictive value for uninvolved quadrants.

INTRODUCTION: Improved preoperative localization facilitates minimally invasive parathyroidectomy for removal of parathyroid lesions therefore preventing an invasive bilateral neck exploration. As 4D-CT has emerged, its high specificity has helped with preoperative parathyroid lesion localization. A high negative predictive value (NPV) would serve to further confirm parathyroid lesion localization and limit unnecessary surgical exploration. This study's objective was to determine the NPV of preoperative 4D-CT and its facilitation of minimally invasive parathyroidectomy. METHODS: A retrospective review was compiled for patients undergoing parathyroidectomy for primary hyperparathyroidism with a preoperative 4D-CT. Included patients were sorted into various groups for comparison: those with 4D-CT localizing to a single lesion, localizing to multiple lesions, and those with nonlocalizing findings; multiple hypercellular parathyroid gland versus single gland findings; extent of surgical exploration; lesion location; and patients with concomitant thyroid nodules. Negative predictive value was calculated and used to quantify the ability for 4D-CT to rule out biochemically significant parathyroid lesions. RESULTS: In our review of 68 patients: sensitivity was 81.3%, specificity was 95.5%, positive predictive value was 87.1%, and negative predictive value was 93.3%. 86% had a single localizing 4D-CT, 7% had a non-localizing 4D-CT, and 7% had a multiple quadrant localizing 4D-CT. NPV for single and multi-localizing 4D-CT were 96.8% and 88.9%, respectively. CONCLUSION: Preoperative 4D-CT has a high negative predictive value (93.3%), suggesting in the majority of cases, a quadrant with no 4D-CT radiographic findings suspicious for parathyroid is unlikely to harbor biochemically significant parathyroid lesions.

P16-positive cystic squamous cell carcinoma in midline neck: metastasis from oropharynx or primary carcinoma arising from thyroglossal duct cyst?

Cystic squamous cell carcinoma (SCC) of the lateral neck is considered metastatic human papilloma-virus (HPV)-related oropharyngeal SCC (HPV-OPSCC) until proven otherwise. P16 immunohistochemistry is diffusely positive in those carcinomas and is used as a surrogate marker of active human papillomavirus (HPV) infection. Thyroglossal duct cysts (TDC) are one of the differential diagnoses for cystic neck lesions. SCC arising from TDC is extremely rare. In this study, we report a p16-positive cystic SCC located in the midline neck. Radiologic features and the presence of thyroid tissue in the cyst wall indicated that it was a TDC. The morphologic features of the lesion raised the question: is the carcinoma metastatic HPV-OPSCC? The HPV confirmative test, high-risk HPV RNA in situ hybridization, was negative. We then studied p16 immunohistochemistry in the squamous epithelium of benign TDC and found that rare benign TDC can show diffuse and strong p16 positivity.

Aplicaciones de la angiografía por TAC en el estudio de la circulación carotídea e intracerebral

Con los recientes progresos en su tecnología, la TACpermite realizar el estudio de Vasos Sanguíneos y territorios Vasculares con gran precisión y mínima invasión del organismo

Radiocirugía: principios y aplicaciones en la práctica clínica

En los últimos años, la introducción de la radiocirugía, en combinación con la microneurocirugía y la neurorradiología intervencionista, ha hecho posible eltratamiento eficaz, de patologías de tipo vascular y tumoral al igual que trastornos funcionales, hasta hace poco intratables o tratables a costa de una elevada morbimortalidad para el paciente. En el presente artículo se hace una revisión de los conceptos básicos de física y radioterapia que debe conocer el médico para tener acceso en forma lógica y segura a esta tecnología. Se revisan las opciones de tratamiento con radiocirugía disponibles hoy día, sus indicaciones, resultados y efectos colaterales. El tema tratado posee enorme importancia para los médicos en general ya que desde hace poco esta tecnología ya está disponible en el país.