Enhanced visualisation of the normal prostate blood flow in young healthy volunteers using a new ultrasound contrast agent

Purpose: To evaluate the sonographic appearance of normal prostate vascularity before and after injection of a new ultrasound contrast agent, Sonazoid (NC100100, Nycomed Amersham). Material and Methods: Five healthy male volunteers were given three injections of Sonazoid each. Transrectal B-mode, colour Doppler and colour Doppler energy (i.e. power Doppler) imaging was performed. The visibility of the vascular pattern and the vascular architecture of the prostate, including dynamics of contrast inflow and blood flow symmetry, were evaluated. Results: The depiction of the vascularity was improved in all subjects after injection of Sonazoid for both Doppler modes. No improvement was seen for B-mode. Contrast dynamics within the prostate vessels were demonstrated with a mean time from injection of the ultrasound contrast agent to enhancement of the Doppler signals in the subcapsular arteries of 14±1 s (11-17 s), and the ultrasound contrast agent reached the central periurethral veins 4-7 s later. A symmetric, radial, spoke-like intraprostatic vascular pattern could be identified in all subjects using power Doppler imaging and ultrasound contrast agent. Conclusion: Sonazoid improved the detection of normal human prostate vascular anatomy for both colour and power Doppler imaging. Contrast dynamic studies revealed a radial spoke-like intraprostatic vascular pattern. This information might be useful in examination of patients with suspicion of prostate cancer, and needs to be further investigated.