Comparison of consecutive bolus tracking and flash replenishment measurements for the assessment of tissue hemodynamics using contrast-enhanced ultrasound (CEUS) in an experimental human squamous cell carcinoma model
Issue title: Papers of the 31st Conference of the German Society for Clinical Microcirculation and Hemorheology, Halle, Germany, 15–16 June 2012
Authors: Paprottka, P.M. | Ingrisch, M. | Koelln, A. | Zengel, P. | Cyran, C.C. | Nikolaou, K. | Reiser, M.F. | Clevert, D.A.
Affiliations: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany | Institute for Ear, Nose and Throat Medicine, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
Note: [] P.M. Paprottka and M. Ingrisch are contributed equally to this article. Corresponding author: Philipp Marius Paprottka, Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistrasse 15, 81377 Munich, Germany. Tel.: +49 89 7095 3620; Fax: +49 89 7095 8832; E-mail: [email protected]
Note: [] P.M. Paprottka and M. Ingrisch are contributed equally to this article.
Abstract: 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 (PEBT), wash-in area-under-the-curve (Wi-AUCBT), mean transit time (MTTBT), wash-in-rate (WiRBT) and perfusion-index (Wi-PIBT) were derived; FR yielded estimates of relative-blood-volume (rBVFR), mean transit time MTTFR, relative blood flow rBFFR and wash-in rate Wi-RFR. Results: In all rats, BT and FR measurements could be completed successfully. Highly significant correlations were observed between rBVFR and PEBT, rBVFR and Wi-AUCBT, rBVFR and MTTBT, rBVFR and WiPIBT, MTTFR and MTTBT, rBFFR and PEBT, rBFFR and Wi-AUCBT, rBFFR and WiRBT, rBFFR and WiPIBT, WiRFR and PEBT, WiRFR and Wi-AUCBT, WiRFR and WiRBT and WiRFR and WiPIBT. 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.
Keywords: Bolus tracking, flash replenishment, contrast-enhanced ultrasound (CEUS), human squamous cell carcinoma, experimental animal model
DOI: 10.3233/CH-2012-1588
Journal: Clinical Hemorheology and Microcirculation, vol. 52, no. 2-4, pp. 107-114, 2012
Issue 2,3,4