MR imaging: normal and invaded cavernous sinus studied with and without Gd-DTPA

Abstract

Clinical efficacy of MR imaging for demonstrating the normal and abnormal cavernous sinus (CS) was evaluated. Six normal CS and six CS invaded by pituitary adenomas were studied with a 0.5 T MR scanner using T1-weighted SE sequences. Furthermore, all normal CS and one invaded CS were studied with gadolinium (Gd)-DTPA. The internal carotid artery (ICA) was shown as low intensity and not enhanced with Gd-DTPA. Venous flow in the CS could be divided into two compartments, i.e., rapid and slow flows. Both flows were demonstrated as lower intensity than the white matter and higher than ICA. Slow flow was markedly enhanced with Gd-DTPA, but rapid flow was enhanced to a lesser degree than the slow. Invasion of the CS was demonstrated as follows: the engulfment of the ICA by the tumor; lack of relatively low intensity of venous flow; the extension of the tumor to the lateral wall of the CS; and the marked displacement of the ICA. MR imaging was useful for the recognition of the blood flows and the tumor invasion in the CS.