Sahar Mirpour MD, Abstract Co-Author: Nothing to Disclose

Anilchandra Attaluri PhD, Abstract Co-Author: Nothing to Disclose

Jorge Guzman RT, Abstract Co-Author: Nothing to Disclose

Laurie Pipitone, Abstract Co-Author: Nothing to Disclose

Juls Blevins, Abstract Co-Author: Nothing to Disclose

Eleni A. Liapi MD, Presenter: Research Grant, Guerbet SA

Robert Ivkov, Abstract Co-Author: Nothing to Disclose

Magnetic hyperthermia therapy (MHT) requires injection of large amounts of iron nanoparticles, which create significant susceptibility artifacts on MRI, precluding thus successful monitoring of tumor perfusion changes following treatment. To prospectively evaluate whether dynamic CT imaging can depict perfusion changes following MHT in the liver VX2 model.

18 liver VX2 tumor bearing rabbits were scanned in a 320-detector row CT scanner (Acquilion One, Toshiba, Japan) before and at 5 days following intra-arterial or direct percutaneous injection of iron oxide nanoparticles mbedded in ethiodized oil and subsequent MHT. The volumetric (non-helical) scanning parameters were: FOV=22 cm, kV=120, mA=80, slice thickness=0.5 mm, scan delay=6 sec, intermittent scanning for 67 sec (arterial phase every 2 sec, portal venous phase every 3 sec). Rabbits were injected with 1.5 ml/kg of isoosmolar CM at 1 ml/sec, followed by a saline flush. CT data were analyzed using the Toshiba CT body perfusion software and calculated tumor perfusion, as well as ipsilateral and contralateral to tumor hepatic perfusion using the maximum slope model. All rabbits were euthanized after the final CT scan and tumor and liver samples were evaluated for percentage of tumor necrosis and iron content with inductively coupled mass spectrometry.

Following MHT, tumor perfusion index was significantly reduced (p=0.03), while arterial flow to the ipsilateral and contralateral to tumor hepatic parenchyma was significantly increased (p=0.006 and P=0.0001, respectively). Mean tumor necrosis was 55.7% of the total tumor area. No correlation was found between the percentage of tumor necrosis and changes in the tumor PI. Mean iron concentration in tumor was 0.45 mg/ml of tissue.

Dynamic CT perfusion imaging can successfully depict changes in liver and tumor perfusion at 5 days following magnetic hyperthermia therapy in the liver VX2 model.

Tumor perfusion changes are of essential importance for monitoring the effects of magnetic hypertehrmia therapy. Dynamic CT perfusion imaging can successfully depict changes in liver and tumor perfusion at 5 days following magnetic hyperthermia therapy in the liver VX2 model.

Mirpour, S, Attaluri, A, Guzman, J, Pipitone, L, Blevins, J, Liapi, E, Ivkov, R, Dynamic Perfusion CT for the Evaluation of Perfusion Changes Following Magnetic Hyperthermia Therapy in the Liver VX2 Model.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14019742.html