Scintigraphic peritoneography reveals a non-uniform 99m Tc- Pertechnetat aerosol distribution pattern for Pressurized Intra- Peritoneal Aerosol Chemotherapy (PIPAC) in a swine model Alexander Bellendorf 1 • Veria Khosrawipour 2,3 • Tanja Khosrawipour 2,3 • Simon Siebigteroth 1 • Joseph Cohnen 1 • David Diaz-Carballo 4 • Andreas Bockisch 1 • Ju ¨ rgen Zieren 3 • Urs Giger-Pabst 2,3 Received: 14 November 2016 / Accepted: 6 June 2017 Ó Springer Science+Business Media, LLC 2017 Abstract Background Although recent data are contradictory, it is still claimed that Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) would deliver an aerosol which distributes homogeneously throughout the entire abdominal cavity. Methods 99m Tc-Pertechnetat was administered in four postmortem swine using either PIPAC or liquid intra- peritoneal chemotherapy (IPC). The animals were exam- ined by planar scintigraphy and SPECT/CT. Planar distri- bution images were divided into four regions of interest (ROIs: right/left upper and lower abdominal quadrant). SPECT/CT slices were scanned for areas of intense nuclide accumulation (‘‘hot spots’’). The percentage of relative distribution for planar scintigraphy was calculated by dividing the summed individual counts of each ROI by total counts measured in the entire abdominal cavity. The relative distribution of the ‘‘hot spots’’ was analyzed by dividing the counts of the local volume of interest (VOI) by the summed volume counts measured in the entire abdominal cavity. Results In all four animals, planar scintigraphy showed inhomogeneous nuclide distribution. After PIPAC only 8–10% of the delivered nuclide was detected in one ROI with a mean deviation of 40% and 74% from a uniform nuclide distribution pattern. In all animals, SPECT/CT revealed ‘‘hot spots’’ beneath the PIPAC Micropump, catheter tip, and in the cul-de-sac region which comprise about 25% of the total amount of delivered nuclide in 2.5% of the volume of the entire abdominal cavity. Conclusions Our present data indicate that the intra-ab- dominal aerosol distribution pattern of PIPAC therapy is non-homogeneous and that the currently applied technol- ogy has still not overcome the problem of inhomogeneous drug distribution of IPC. Keywords MIP Ò Á Aerosol Á Distribution Á Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) Á 99m Tc- Pertechnetat Á Peritoneography Abbreviations CO 2 Carbon dioxide CT Computed tomography IAP Intra-abdominal pressure IPC Intra-peritoneal chemotherapy LDR Left side–dorsal–right side PM Peritoneal metastasis PIPAC Pressurized Intra-Peritoneal Aerosol Chemotherapy MBq Mega Becquerel MIP Ò Micropump (Reger Medizintechnik, Rottweil, Germany) ROI Region of interest RVL Right side–ventral–left side Alexander Bellendorf and Veria Khosrawipour have contributed equally to this work. & Urs Giger-Pabst urs.pabst@elisabethgruppe.de 1 Department of Nuclear Medicine, University Hospital Essen, Essen, Germany 2 Basic Research Laboratory Department of Surgery, St. Mary’s Hospital Herne, Ruhr University Bochum, Bochum, Germany 3 Department of Surgery & Therapy Center for Peritonealcarcinomatosis, St. Mary’s Hospital Herne, Ruhr University Bochum, Bochum, Germany 4 Hematology & Medical Oncology, St. Mary’s Hospital Herne, Ruhr University Bochum, Bochum, Germany 123 Surg Endosc DOI 10.1007/s00464-017-5652-4 and Other Interventional Techniques