Purpose: We examined untreated and irradiated choroidal melanomas with color Doppler imaging (CDI), a noninvasive method providing quantitative measures of blood flow, to determine if the tumor vessel damage associated with irradiation can be detected using this technology.
Methods: CDI was performed on 122 untreated and 76 previously irradiated tumors using a Q2000 color Doppler ultrasound unit. Spectral analysis was performed on all detectable vascular regions within the tumor to obtain estimates of the peak systolic and end diastolic flow velocities and resistive index ((syst-diast)/syst).
Results: Vessels were detected in 93% of the untreated tumors and in 63% of the treated tumors (p<0.001, X2), and the median number of vascular regions found was higher among untreated tumors (3 vs 1, p=0.001, Wilcoxon Rank Sum). The effect of treatment status on the detection of tumor vessels was significant (p=0.039), controlling for age, sex, largest tumor pretreatment diameter, and tumor height at CDI in a logistic regression model. Mean resistive index was lower in the untreated tumors (0.53 vs 0.58, p=0.0050), controlling for tumor height and other covariates in an analysis of variance.
Conclusions: On examination with CDI, irradiated tumors had fewer detectable vascular regions and greater resistance to flow than untreated tumors, a pattern consistent with known radiation effects.