IMPLANTABLE INSULIN PUMPS - DIAGNOSIS AND MANAGEMENT OF DECREASED FLOW-RATES USING RADIONUCLIDE INVESTIGATION

The aim of this study was to develop a diagnostic procedure for pumpin g unit malfunction by radionuclide imaging (RI) and to Validate the me thod by comparing the results with those obtained using more conventio nal methods. Fifteen radionuclide investigations were performed in 11 patients with intraperitoneal implantable insulin pumps. One mCi of 99 mTc in 1 mi isotonic sodium chloride was injected into the reservoir The results based on catheter visualization and peritoneal accumulatio n were compared blindly to the efficacy of alkaline rinses and laparos copic findings. In all RI stoppage cases except one alkaline rinses fa iled to restore flow Where laparoscopy was performed, comparisons were concordant i.e. no outflow from the tip of the catheter. The RI image s obtained were reproduced in vitro using a pump under normal flow con ditions and complete proximal and distal catheter obstruction. RI is a safe, quick non invasive method which allows the location of the site of pump/catheter malfunction within a one step procedure and the pred iction of the efficacy of sodium hydroxide rinses.