Abstract: TH-PO746
Determination of Renal Blood Flow Based on PET/CT-Rubidium-82-Technology in Healthy Subjects
Session Information
- Bioengineering
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bioengineering
- 300 Bioengineering
Authors
- Langaa, Stine, University Clinic of Nephrology and Hypertension, Holstebro Hospital, Holstebro, Denmark
- Lauridsen, Thomas G., University Clinic of Nephrology and Hypertension, Holstebro Hospital, Holstebro, Denmark
- Fynbo, Claire A., Department of Nuclearmedicine, Herning Hospital, Herning, Denmark
- Theil, Jorn, Department of Nuclearmedicine, Herning Hospital, Herning, Denmark
- Bech, Jesper N., University Clinic of Nephrology and Hypertension, Holstebro Hospital, Holstebro, Denmark
Background
Changes in Renal Blood Flow (RBF) play an important patophysiological role in the widespread diseases hypertension and kidney disease. However present methods for RBF-determination in humans have several disadvantages. Myocardial blood flow is routinely assessed with PET/CT and the perfusion tracer rubidium-82 (Rb-82). Renal PET with Rb-82 has shown great promise regarding determination of RBF.
The purpose of the study is to develop a new and reliable method for determination of RBF based on PET/CT and Rb-82 using a 1-tissue compartment model. To minimize radiation exposure, the input function in the model and the kidneys have to be in the same field of view. Therefore we examined whether the abdominal aorta (AA) is a valid alternative as input function instead of the left ventricular blood pool (LVBP) which is routinely used.
Methods
10 healthy subjects underwent dynamic PET/CT-scans with Rb-82 as perfusion tracer in two different bed positions. Rb-82 was given as bolus injections. Volumes of interest were placed in the kidneys, LVBP and AA and time activity curves were generated. An input function was derived from both the LVBP and AA. A 1-tissue compartment model was used for estimation of RBF. The K1-parameter represents RBF. K1-values derived from the two different input functions were compared.
Results
The mean K1-value derived from LVBP was 2.14 ± 0.52 ml/min/g and 2.11 ± 0.57 ml/min/g for the right and left kidney respectively. The mean K1-value derived from AA was 2.69 ± 0.40 ml/min/g and 2.77 ± 0.77 ml/min/g for the right and left kidney respectively. For both input functions, the mean K1-value for the right kidney was not significantly different from the mean K1-value for the left kidney. For LVBP the intra-assay variation coefficient was 14.7% for the right kidney and 12.2% for the left kidney. For AA the intra-assay variation coefficient was 12.7% and 13.2% for the right and left kidney respectively.
Conclusion
Our preliminary results show that the PET-Rb-82 method is feasible for determination of RBF. Use of AA-activity as input function seems to be physiologically most valid because of the direct input to the renal arteries and the derived K1-values are significantly higher than K1-values obtained using activity from LVBP.
Funding
- Government Support - Non-U.S.