Rationale and objectives: To evaluate the diagnostic value of the new ultrasound mode "wide-band harmonic" (WBH) using an ultrasound contrast agent in blunt renal trauma in an animal model.
Methods: A defined blunt renal trauma was induced in 10 rabbits according to published standards. Ultrasound (B-mode, color and power Doppler, WBH) was performed before and after trauma, with and without using a contrast agent (Levovist). Ultrasound features were compared with histologic findings.
Results: In 2 of the 10 rabbits, three focal renal intraparenchymal lesions with diameters ranging from 1.0 to 1.8 mm were found that could be identified only using WBH with contrast. Six of the 10 rabbits developed a subcapsular hematoma with a thickness of up to 1.5 mm, which was identified by conventional B-mode as well as WBH. Histologic workup confirmed these findings of intraparenchymal hematomas and did not reveal further lesions.
Conclusions: Only 20% of the experimental subjects developed parenchymal lesions with diameters of 1.0 mm or larger. All these lesions were identified only using WBH. These results indicate the potential to use WBH plus contrast for the diagnosis of blunt renal trauma.