Purpose: To evaluate “bolus-tracking” (BT) and “flash-replenishment” (FR) for the assessment of tissue hemodynamics by contrast-enhanced ultrasound (CEUS) in an experimental small-animal-squamous-cell-carcinoma-model. Since the underlying tissue is the same, strong correlations between parameter outcomes of both techniques are expected. Methods and materials: Human hypopharynx-carcinoma-cells were subcutaneously injected into the left flank of 18 female athymic-nude-rats. After 10 days of subcutaneous tumour growth, bolus tracking and flash-replenishment measurements were performed consecutively in the same imaging plane in each rat after bolus-injection of SonoVue via the lateral tail vein using a high-end ultrasound system with a 15 MHz probe. Video-sequences were analysed with dedicated software (VueBox^®, Bracco-Suisse^®). From BT measurements, the parameters peak enhancement (PE_BT), wash-in area-under-the-curve (Wi-AUC_BT), mean transit time (MTT_BT), wash-in-rate (WiR_BT) and perfusion-index (Wi-PI_BT) were derived; FR yielded estimates of relative-blood-volume (rBV_FR), mean transit time MTT_FR, relative blood flow rBF_FR and wash-in rate Wi-R_FR. Results: In all rats, BT and FR measurements could be completed successfully. Highly significant correlations were observed between rBV_FR and PE_BT, rBV_FR and Wi-AUC_BT, rBV_FR and MTT_BT, rBV_FR and WiPI_BT, MTT_FR and MTT_BT, rBF_FR and PE_BT, rBF_FR and Wi-AUC_BT, rBF_FR and WiR_BT, rBF_FR and WiPI_BT, WiR_FR and PE_BT, WiR_FR and Wi-AUC_BT, WiR_FR and WiR_BT and WiR_FR and WiPI_BT. Conclusion: Whereas bolus tracking can be used in a wide range of modalities including CEUS, CT and MR, FR as a technique for the assessment of tissue hemodynamics is unique to CEUS. Although BT and FR yield different parameters, the underlying tissue hemodynamics are equal. In this work, we were able to demonstrate strong correlations between different parameters of both modalities in a small-animal-tumor-model, indicating that flash-replenishment is a valid alternative to the more established bolus-tracking technique. Although the lack of absolute, quantitative parameters hinders a direct comparison of both modalities, FR and BT should both be suitable for a relative comparison, e.g. between baseline and follow-up examinations.