[Diagnosis of carotid body tumor by imaging procedures]

The imaging techniques available for the diagnosis of tumors of the glomus caroticum are discussed with reference to four cases (three patients, one with tumor bilaterally). Taking into consideration the practicability and invasiveness of the investigations as well as the risks and costs involved, we propose that the procedures be performed in the following sequence: ultrasonography, Doppler ultrasonography, computed tomography (CT) or (even better) magnetic resonance imaging (MRI), and selective angiography. In most cases where there is a non-inflammatory mass in the neck, ultrasonography and Doppler ultrasonography may be adequate to establish the diagnosis of a glomus caroticum tumor. B-scan ultrasonography reveals an inhomogeneous mass that pushes the carotid arteries apart and an arteriovenous shunt may be seen using the Doppler technique. CT and MRI show the full extent of the tumor and provide information about infiltration of adjacent structures. Selective intra-arterial angiography confirms the diagnosis, demonstrating a profound vascularized tumor in the carotid bifurcation. If angiography leads to identification of an afferent vessel, selective embolization of the tumor may be performed, thus enabling a much safer operation with less blood loss.