Preoperatory diagnosis of clinically significant parathyroid cysts has been possib!e through physical, chemical, immunological, and cytological examination of the fluid obtained by fine needle aspiration puncture of the cysts.Cystic fluid is colorless. Immunological tests for thyroglobulin were consistently negative. No spontaneous coagulation was observed. Upon cytological examination only a few desquamation cell debris were found after centrifugation of the specimen. Standard chemical determinations were performed. Over a 11 year period, 18 cases have been studied: 9 wereoperated upon histologic diagnosis of parathyroid cysts been accomplished in all of them.The test employed enables the differential diagnosis between parathyroid cysts and cysts of thyroid origin, lymphangiomata, branchial and hydatid cysts.

El diagnóstico preoperatorio de los quistes paratiroideos clínicamente significativos ha sido posible a través del examen físico, químico, inmunológico y citológico del líquido obtenido por medio de la punción con aguja fina.El líquido es incoloro. La investigación de tiroglobulina ha sido siempre negativa. No coagula espontáneamente. El estudio citológico luego de su centrifugación sólo muestra restos celulares. Se practicaron determinaciones químicas de rutina. Durante un periodo de 11 años se han estudiado 18 casos: 9 fueronoperados y en todos ellos el diagnóstico histológico fue de quiste paratiroideo.El test empleado permite el diagnóstico diferencialentre quistes paratiroideos y quistes de origen tiroideo,linfangiomas, quistes branquiales y quistes hidáticos