[Sonographic diagnosis and differential diagnosis of neck cysts]

We report 101 patients with the clinical diagnosis of a branchial cyst investigated by ultrasonography. In 78 cases the diagnosis of a branchial cyst was confirmed by the ultrasound findings. The picture of a typical cyst was found in 26 cases, whereas a complex cyst filled with sludge or debris was found in 52 patients. Histology revealed a different diagnosis in 7 cases of ultrasonic complex cysts. Of 23 patients where a branchial cyst was excluded by ultrasound, histology showed a lesion other than a branchial cyst in 19 cases. In total, only 34.6% of the histologically confirmed branchial cysts displayed the typical signs of such a cyst on ultrasonography. However, in 91% of the patients with an actual branchial cyst we were able to confirm the diagnosis by ultrasound before operation. The differential diagnosis of other benign and malignant lesions of the neck resembling branchial cysts is discussed with examples.