Abstract:
:Sequential albumin-Gd-DTPA and Gd-DTPA dynamic enhancement studies were performed in an animal tumor model for the comparison of regional vascularity and permeability parameters measured by these two different sizes of contrast agents. The early albumin-Gd-DTPA enhancement arises from the vascular compartment, and the averaged signal enhancement derived from the first 3 to first 6 images postinjection can be reliably used to assess vascularity. The signal intensity in the images during the period of 5-10 min post-albumin-Gd-DTPA injection shows a steady linear variation. The intercept of the linear relationship is another indicator of the vascularity and the slope represents the tumor permeability to albumin-Gd-DTPA. The Gd-DTPA enhancement study was analyzed by a two-compartmental pharmacokinetic model to calculate the regional vascularity and permeability. The permeability parameters measured from albumin-Gd-DTPA and Gd-DTPA show an excellent correlation. The vascularity parameters measured from albumin-Gd-DTPA show good linear correlation with the low vascularity groups measured by Gd-DTPA, but show saturation for the high vascularity groups. The enhancement mechanisms for both contrast agents are discussed to relate the imaging parameters to the physiological variables.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Su MY,Najafi AA,Nalcioglu Odoi
10.1002/mrm.1910340318subject
Has Abstractpub_date
1995-09-01 00:00:00pages
402-11issue
3eissn
0740-3194issn
1522-2594journal_volume
34pub_type
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journal_title:Magnetic resonance in medicine
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