Cervical mediastinic emphysema usually does not demand emergency procedures: nevertheless its ethiology must be promptly assessed though his achievement may prove less than easy owing the vague clinical presentation and to the limits imposed by regional topography. Among the possible etiologic factors one should take into account the rare abdominal source too. Indeed the cervical region is connected to the retroperitoneal space through a virtual "visceral space" via the thoracic cavity and some diaphragmatic break-throughs variable in size. The communication allows, in some pathologic conditions, the unopposed circulation of air and fluids. Our interest in the topic is due to the occurrence of a cervical mediastinic emphysema in a patient suffering from a colonic perforation.