Imaging Diagnosis of Carotid Body Tumor

Objective:To compare the imaging manifestations of ultrasonography,CT,MRI and DSA for improving preoperative diagnosis of carotid body tumors(CBT).Methods:Fourteen cases of CBT were confirmed by pathology,including 10 cases of unilateral ones and 4 cases of bilateral ones.The imaging manifestations of CBT were analyzed retrospectively.Results:Each imaging examination could display well the location,size and form of the tumor.The specific sonogram of CBT was isoechoic or hypoechoic solid lesion and small tubular areas could be seen in masses measured over 3cm in diameter,but the upper borderline of the tumor appeared indistinctive.Colour Doppler ultrasound showed web-like vessels inside the tumor in 9 cases,and 1 case was misdiagnosed as schwannoma.The rate of correct diagnosis was 93%(14/15).Fourteen cases were examined by helical CT enhancement,which reflected the hypervascular nature of CBT.In 12 cases the tumor could not be distinguished from the internal and the external carotid arteries because they were evenly enhanced and 2 cases were unevenly enhanced.The CT values were 150～180HU.The preoperatiove correct diagnosis rate was 100%(14/14).Eleven cases were examined with MRI and MRA.MRI imaging of CBT featured flow-void tumor vessels,and internal and external carotid arteries attached to or embedded respectively in the rear and the front of the external side of masses,distinctively seperated.MRA showed clearly the distinction between CBT and common carotid arteries and their branches.The rate of correct diagnosis was 100%(11/11).Eleven cases were examined with DSA.Angiography could confirm diagnosis and showed feeding vessels.The rate of correct diagnosis was 100%(8/8).Conclusion:Ultrasound,CT and MRI are valuable and specific in diagnosis of CBT.There is no statistically significant difference in 4 kinds of imaging diagnostic methoes.