[Possible application of a signal enhancer for duplex ultrasound in otorhinolaryngology]

Vascularization is a characteristic of malignant tumor growth. It is possible to distinguish between benign and malignant tumors and lymph nodes of the head and the neck by their pattern of blood vessels which can be detected by color image ultrasonography. Unfortunately this detection is often unsuccessful because the vessels are too small.

Four cases (lymph node metastasis, chronic lymph node inflammation, Morbus Hodgkin, cancer of the floor of the mouth) are demonstrated. The vascularization of the masses was detected before and after the injection of Levovist, a contrast agent which is known to amplify the duplex signal up to 25 dB.

In all of the demonstrated cases, a similar pattern of intranodal vessels was detected before the application of Levovist. After the injection an enhancement of the duplex signal could always be detected within the first minute and differences of the intratumoral pattern of the blood vessels between the cases could be identified.

Levovist results in an increased detection of intratumoral blood vessels detected by color image ultrasonography. Further studies are necessary to check whether its application results in an increase of the specificity of the examination.