Objective To explore the feasibility of magnetic compression technique (MCR) in the treatment of severe single mid-ureteral stricture in a rabbit model. Methods After 10 female New Zealand rabbits were selected, the distal end of the right ureter was ligated with silk thread. Two weeks after the operation, when the right ureter was dilated, the mid-ureter was ligated again with silk thread to create a severe single mid-ureteral stricture animal model. Longitudinal incisions were made at the upper and lower ends of the ligation site, and cylindrical NdFeB magnets with central holes (sub-magnets and main magnets) were placed to anastomose and recanalize the mid-ureteral stricture. The magnets were adjusted to the appropriate position to automatically align and attract each other. The longitudinal incision sites of the ureter were sutured with 6-0 Prolene thread, and the abdominal cavity was closed layer by layer. The operation time was recorded. X-ray films were taken every two days to confirm the position of the magnets and record the time of magnet detachment. Three weeks after the operation, the anastomotic specimens were obtained, and the formation of the anastomosis was evaluated with gross observation and histological staining. Results Two weeks after ligation, all experimental rabbits showed obvious dilation of the right ureter. The mid-ureteral ligation and placement of the male and female magnets were successfully completed in all 10 experimental rabbits, with an operation time of (24.00±5.15)minutes. The male and female magnets attracted each other well. X-ray examination showed that the magnets detached and entered the distal ureter (14.0±1.9) days after magnetic compression. The recanalization of the severe single mid-ureteral stricture was successfully achieved. The gross specimens and histological examination of the anastomosis showed that the anastomosis remained patent and the mucosal healing was good. All experimental rabbits survived well after the operation without serious complications. Conclusion MCT provides a new idea and novel method for the treatment of mid-ureteral stricture. This study confirmed the feasibility of this technique in treating severe single mid-ureteral stricture in a rabbit model. The operation is relatively simple and has potential for clinical application.

[Objective] To explore the clinical features of IgG4-related urinary diseases so as to provide reference for the diagnosis and treatment of such diseases. [Methods] The clinical data of 4 cases of IgG4-related urinary system diseases diagnosed and treated in Xijing Hospital of Air Force Medical University during Aug.2019 and Dec.2023 were retrospectively collected.Here, we report on the diagnosis and treatment of these patients, analysing their symptoms, serology, imaging and pathology as well as their treatment and outcomes. [Results] The patients included 2 male and 2 female.The lesions were involved with the retroperitoneum and urinary system.Three patients had symptoms of lumbar pain.The imaging manifestations were complex, including retroperitoneal mass involving urinary system organs in 2 cases, tabdense shadow of the right kidney in 1 case, and simple cystic mass of kidney in 1 case.Serum IgG4 value was not detected before surgery.All patients underwent radical surgical treatment.Postoperative pathology showed fibrous tissue hyperplasia with a large number of plasma cells, lymphocytes, a few neutrophil infiltrates, and lymphoid follicles and obliterated vasculitis in some specimens.The number of IgG4⁺ plasma cells was more than 10 in all tissues under high power microscope.After surgery, 3 patients had symptoms improved, and serum IgG4 value was within the normal range; 1 patient (patem 3) had elevated IgG4 value during follow-up, received subsequent hormone therapy, and the serum IgG 4 level remained stable. [Conclusion] The symptoms of IgG4-related diseases involving the urinary system are non-specific, and the imaging findings are various, easily confused with other diseases.Early detection of serum IgG4 and biopsy pathology can help clinicians make correct diagnosis in the early stage.