A Novel and Less Traumatic Needle for Kidney Puncture: Development and Preclinical Study Results

Abstract

Introduction. A considerable proportion of PCNL complications occur during renal puncture. An option to decrease the complications rate is needle modification to make the procedure less traumatic. We aimed to evaluate the effectiveness of the novel MG needle in a pre-clinical study. Materials & methods. We developed an original MG needle based on the Veress needle concept containing an atraumatic (blunt) mandrin connected through a spring to the cannula. The MG needle’s properties were compared with those of the conventional Chiba and Trocar needles in two experiments. In the first experiment, we assessed the force required to puncture the model. In the second experiment, we punctured a porcine kidney and analysed histology after the puncture. Results. We performed a series of 30 punctures of polypropylene block by each needle. The force required to make a puncture with the Chiba needle (6.53 ± 0.87 N) was significantly lower compared to the MG needle (7.1 ± 1.07 N), p=0.027. However, the MG needle turned out to be superior to the Trocar needle (8.71 ± 1.08 N), p=0.001. A total of 15 specimen were obtained after 3 renal punctures were made with each needle. A microscopy of the specimen after puncture with the Chiba and Trocar needles showed small fragments of epithelium and erythrocytes inside the canal with uneven margins where the needle passed. A microscopy of the specimen after puncture with a novel MG needle showed a canal with even margins. No tissue fragments inside the canal were observed. Conclusion. The force required to puncture with the novel MG needle is comparable to conventional needles. According to preclinical experiments, histology of porcine kidney indicates that renal puncture with an MG needle is less traumatic. It may reduce the risk of bleeding, and this should be proved during clinical trials.