Kubiak Rainer, Hornok Zita, Csukas Domokos, Ferencz Andrea, Cserni Tamas
Department of Pediatric Surgery, Children's Hospital of Eastern Switzerland, Sankt Gallen, Switzerland.
Department of Pediatric Surgery, Hungarian Reformed Church Bethesda Children's Hospital, Budapest, Hungary.
Eur J Pediatr Surg. 2025 Aug;35(4):316-321. doi: 10.1055/a-2507-8135. Epub 2025 Jan 20.
The pyeloureteral anastomosis remains the most challenging part of pyeloplasty. A purpose-built anastomotic device could simplify this step and potentially improve outcomes. The concept of a pyeloureteral magnetic anastomosis device (PUMA) was proven in minipigs, but only in short term. Our aim was to test the PUMA in domestic pigs and achieve a prolonged follow-up period.
Five female domestic pigs underwent laparoscopy and ligation of the left ureter. Four weeks later, laparoscopic implantation of the PUMA was planned. Removal of the device and a retrograde contrast study were scheduled after another 4 weeks. The experiment was terminated when the animals could no longer be properly cared for due to their weight.
Due to unexpected smaller ureteric diameters, a modified PUMA could only be successfully inserted in pig number 3 (49 kg). Four weeks later, the device was found to be dislocated, but the anastomosis remained patent. After modifying the study protocol, the PUMA was successfully implanted in pigs number 4 (96 kg) and 5 (68 kg) 8 weeks after ureteric ligation. Pig 4 developed malignant hyperthermia and died. In pig 5, the magnets were removed 4 weeks later. After an additional 8 weeks, the animal reached 135 kg and was terminated. The anastomosis remained patent and preserved its diameter.
Despite limitations, our study successfully demonstrated that the PUMA can achieve a patent ureteric anastomosis in domestic pigs. This suggests a potential for minimally invasive ureteric anastomosis in clinical settings. Further research is needed to optimize the technique and validate its effectiveness in humans.
肾盂输尿管吻合术仍然是肾盂成形术中最具挑战性的部分。一种专门设计的吻合装置可以简化这一步骤，并有可能改善手术效果。肾盂输尿管磁性吻合装置（PUMA）的概念已在小型猪身上得到验证，但仅为短期验证。我们的目的是在家猪身上测试PUMA，并实现更长的随访期。
五只雌性家猪接受腹腔镜检查并结扎左侧输尿管。四周后，计划进行腹腔镜下植入PUMA。再过四周后安排取出装置并进行逆行造影研究。当动物因体重原因无法再得到妥善照顾时，实验终止。
由于输尿管直径意外变小，改良后的PUMA仅在3号猪（49千克）身上成功插入。四周后，发现装置移位，但吻合口仍然通畅。在修改研究方案后，PUMA在输尿管结扎8周后成功植入4号猪（96千克）和5号猪（68千克）体内。4号猪发生恶性高热并死亡。在5号猪身上，四周后取出磁体。再过八周后，这只动物体重达到135千克，实验终止。吻合口仍然通畅，直径保持不变。
尽管存在局限性，但我们的研究成功证明了PUMA在家猪身上能够实现输尿管吻合口通畅。这表明在临床环境中进行微创输尿管吻合术具有潜力。需要进一步研究来优化该技术并验证其在人体中的有效性。
