[Determination of the distribution volume of contrast media solutions injected intrahepatically: pre-pilot studies for intratumoral gene therapy].

Determination of the intrahepatic distribution volume of two contrast media (CM) by CT-guided application in an ex-vivo and an in-vivo model (pig liver). In pig livers ex-vivo and in-vivo, 131 CT-guided injections of two different CM (Imagopaque(R), Visipaque(R)) were performed using catheters and cannula with and without side-holes and documented by spiral CT. The distribution pattern was assessed visually: interstitial, subcapsular, vascular/tubular, the distribution volume was quantified using a density mask (thresholds 70/400 HE). Purely interstitial applications were achieved more frequently in-vivo than ex-vivo (p = 0.001). There were no relevant differences between the two CM. Catheters without side-holes led to more interstitial CM depots than catheters with side-holes (p = 0.005). The mean distribution volume was larger with catheters with side-holes (ex-vivo 103 cm(3), in-vivo 19 cm(3)) than with catheters without side-holes (ex-vivo 67 cm(3), in-vivo 13 cm(3)) (p = 0,01). At the same time, the mean density with catheters with side-holes (102 HE) was lower than with catheters without side-holes (115 HE) (p = 0.005). Marked differences of the CM distribution volumes were observed between ex-vivo and in-vivo studies in the pig model. Catheters with side-holes are far superior to catheters without.