Quantitative color Doppler imaging in untreated and irradiated choroidal melanoma

Histological data indicate the importance of tumor vascularization as a determinant of the biological behavior and the response to radiotherapy in choroidal melanoma. Duplex ultrasound and color Doppler imaging, the combination of B-mode ultrasound and pulse-waved Doppler analysis, were used to measure quantitatively neovascular blood flow in 31 patients with choroidal melanoma. Follow-up studies (20 patients) were performed to investigate the change of tumor blood flow in choroidal melanomas after radiotherapy. Blood flow was detected in 30 out of 31 melanomas (size 3.1-17.8 mm) within the tumor and at the tumor base with a mean peak systolic frequency of 1.0 kHz (range 0.3-2.7 kHz), a mean end diastolic frequency of 0.3 kHz (range 0.1-1.0 kHz), and a mean frequency of 0.7 kHz (range 0.2-1.3 kHz). Two and six months after 106Ru/106Rh beta-ray application, 19 patients showed a significant decrease in peak systolic frequency. This occurred with and in advance of the decrease in the tumor size. In one patient, a rising maximum systolic frequency after radiotherapy marked a recurrent tumor growth. Results indicate that the quantitative measurement of tumor blood flow by duplex ultrasound and color Doppler imaging may be a new diagnostic modality for monitoring the effectiveness of radiotherapy in choroidal melanoma.