[Comparison of CT and MRI in diagnosis of parapharyngeal tumors].
Recently, the usefulness of CT and MRI in diagnosing parapharyngeal tumors has been established. At the same time, several modalities for these imagings, i.e. plane and enhanced CT, T1, 2 weighted MRI and Gadolinium enhanced MRI, have been developed. We compared the image findings of 12 tumors involving the parapharyngeal space with their operative records. T1 was most suited to diagnosing the sites of origins of tumors because of its superior depiction of the internal carotid artery and parapharyngeal fat. Enhanced CT was also superior in depicting these structures, but in cases where the parapharyngeal fat was diminished, or the parapharyngeal fat had been invaded by malignant tumor, enhanced CT was inferior to T1. The spatial resolution of T2 was poor, T2 was thus not useful in diagnosing the sites of origins of tumors. Because tumor intensity tended to be similar to that of fat in Gadolinium enhanced MRI imaging, Gadolinium was not as useful as T1. In diagnosing the extents of tumors, we examined the depiction of both tumor-fat and tumor-muscle interfaces. With regard to the depiction of the tumor-fat interface, enhanced CT and T1 were most useful. In diagnosing the tumor-muscle interface, Gadolinium enhanced MRI was most suitable. The net result is that MRI is superior to CT.
Kase
Y
Y
Department of Otolaryngology, Tokyo University Branch Hospital.
Yamane
M
M
Ichimura
K
K
Iinuma
T
T
D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D010610:Pharyngeal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed