University of Heidelberg
Faculty of Medicine Mannheim
University Hospital Mannheim
News
These pages are still under constructions and will be available soon! Please check again later!
Note


If you have questions concerning a specific publication please use this form with subject 'information about publications' and giving the full citation in the message body.

Links
Home > Publications > Abstract >

Assessment of renal function after conformal radiotherapy and intensity-modulated radiotherapy by functional (1)H-MRI and (23)Na-MRI

S. Haneder, H. Michaely, S. Schoenberg, S. Konstandin, L. Schad, K. Siebenlist, H. Wertz, F. Wenz, F. Lohr and J. Boda-Heggemann

Strahlenther Onkol, 188 (12), pp.1146-1154

PURPOSE: Adjuvant radiochemotherapy (RCHT) improves survival of patients with locally advanced gastric cancer. Conventional three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to a significant amount of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides excellent target coverage with improved kidney sparing. Few long-term results on IMRT for gastric cancer, however, have been published. Functional magnetic resonance imaging (fMRI) at 3.0 T including blood oxygenation-level dependent (BOLD) imaging, diffusion-weighted imaging (DWI) and, for the first time, (23)Na imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT. PATIENTS AND METHODS: Four disease-free patients (2 after 3D-CRT and 2 after IMRT; FU for all patients >?5 years) were included in this feasibility study. Morphological sequences, axial DWI images, 2D-gradient echo (GRE)-BOLD images, and (23)Na images were acquired. Mean values/standard deviations for ((23)Na), the apparent diffusion coefficient (ADC), and R2* values were calculated for the upper/middle/lower parts of both kidneys. Corticomedullary (23)Na-concentration gradients were determined. RESULTS: Surprisingly, IG-IMRT patients showed no morphological alterations and no statistically significant differences of ADC and R2* values in all renal parts. Values for mean corticomedullary (23)Na-concentration matched those for healthy volunteers. Results were similar in 3D-CRT patients, except for the cranial part of the left kidney. This was atrophic and presented significantly reduced functional parameters (p?=?0.001-p?=?0.033). Reduced ADC values indicated reduced cell density and reduced extracellular space. Cortical and medullary R2* values of the left cranial kidney in the 3D-CRT group were higher, indicating more deoxygenated hemoglobin due to reduced blood flow/oxygenation. ((23)Na) of the renal cranial parts in the 3D-CRT group was significantly reduced, while the expected corticomedullary (23)Na-concentration gradient was partially conserved. CONCLUSIONS: Functional MRI can assess postradiotherapeutic renal changes. As expected, marked morphological/functional effects were observed in high-dose areas (3D-CRT), while, unexpectedly, no alteration in kidney function was observed in IG-IMRT patients, supporting the hypothesis that reducing total/fractional dose to the renal parenchyma by IMRT is clinically beneficial.

Contact: Dr. Frank Zöllner last modified: 06.11.2019
to top of page