% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Piechotta:132727, author = {P. L. Piechotta and D. Bonekamp$^*$ and M. Sill$^*$ and A. Wick and W. Wick$^*$ and M. Bendszus and P. Kickingereder}, title = {{I}ncreased {D}elay {B}etween {G}adolinium {C}helate {A}dministration and {T}1-{W}eighted {M}agnetic {R}esonance {I}maging {A}cquisition {I}ncreases {C}ontrast-{E}nhancing {T}umor {V}olumes and {T}1 {I}ntensities in {B}rain {T}umor {P}atients.}, journal = {Investigative radiology}, volume = {53}, number = {4}, issn = {0020-9996}, address = {Philadelphia, Pa.}, publisher = {Lippincott Williams $\&$ Wilkins}, reportid = {DKFZ-2018-00381}, pages = {223 - 228}, year = {2018}, abstract = {The aim of this study was to evaluate the impact of delayed T1-weighted (T1-w) MRI acquisition after gadolinium chelate administration on brain tumor volumes and T1-w intensities.Fifty-five patients with histologically confirmed, contrast-enhancing intra-axial brain tumors were analyzed in this prospective test-retest study. Patients underwent 2 consecutive 3 T MRI scans (separated by a 1-minute break) during routine follow-up with contrast-enhanced T1 (ceT1-w), T2, and FLAIR acquisition. Macrocyclic gadolinium chelate-based contrast agent was only administered before the first ceT1-w acquisition; median latency to ceT1-w acquisition was 6.72 minutes (IQR, 6.53-6.92) in the first and 16.27 minutes (IQR, 15.49-17.26) in the second scan. Changes in tumor volumes and relative ceT1-w intensities between the 2 acquisitions were quantitatively assessed following semiautomated tumor segmentation (separately for contrast-enhancement [CE], necrosis [NEC], and nonenhancing [NE] tumor).Semiautomatically segmented CE tumor volumes were significantly larger in the second acquisition (median $+32\%$ [1.2 cm]; IQR, $16\%-62\%;$ P < 0.01), which corresponded to a $10\%$ increase in CE tumor diameter (+0.3 cm). Contrarily, NEC and NE tumor volumes were significantly smaller (median $-24\%$ [IQR, $-36\%$ to $-54\%],$ P < 0.01 for NEC and $-2\%$ [IQR, $-1\%$ to $-3\%],$ P = 0.02 for NE tumor). Bland-Altman plots confirmed a proportional bias toward higher CE and lower NEC volumes for the second ceT1-w acquisition. Relative ceT1-w intensities for both early- (regions already enhancing in the first scan) and late-enhancing (newly enhancing regions in the second scan) tumor were significantly increased in the second acquisition (by $5.8\%$ and $27.3\%$ [P < 0.01, respectively]). Linear-mixed effects modeling confirmed that the increase in CE volumes and CE intensities is a function of the interval between contrast agent injection and ceT1-w acquisition (P < 0.01 each).Our study indicates that the maximum extent of CE tumor volumes and intensities may increase beyond the time frame of 4 to 8 minutes after contrast agent injection and potentially affects the diagnosis of progressive or recurrent disease because late-enhancing recurrent disease might not be unequivocally detected on standard follow-up MRI.}, cin = {E010 / C060 / L101 / G370}, ddc = {610}, cid = {I:(DE-He78)E010-20160331 / I:(DE-He78)C060-20160331 / I:(DE-He78)L101-20160331 / I:(DE-He78)G370-20160331}, pnm = {315 - Imaging and radiooncology (POF3-315)}, pid = {G:(DE-HGF)POF3-315}, typ = {PUB:(DE-HGF)16}, pubmed = {pmid:29200014}, doi = {10.1097/RLI.0000000000000432}, url = {https://inrepo02.dkfz.de/record/132727}, }