NITI-S ENTERAL COLONIC UNCOVERED STENT

Additional Manufacturer Narrative

IT WAS REPORTED THAT WHEN THE PROCEDURE BEGAN, THE STENT DEPLOYED PREMATURELY AND RETRIEVAL WAS UNSUCCESSFUL. ADDITIONAL STENT PLACEMENT WAS ATTEMPTED BUT FAILED, RESULTED IN COLOSTOMY. BASED ON THE ATTACHED PHOTO, IT WAS CONFIRMED THAT THE DELIVERY SYSTEM WAS BROKEN. IT WAS CONFIRMED FROM THE DEVICE HISTORY RECORD THAT DEVICE HAD BEEN MANUFACTURED WITH NO SIGNIFICANT ISSUE AND PASSED ALL THE INSPECTIONS SUCCESSFULLY. COLON STRUCTURE WHERE STENT WAS IMPLANTED IS CURVY. IT CAN BE HARD TO DEPLOY DUE TO PRESSURE GENERATED BY PATIENT'S BENDED LESION. IN ADDITION, THIS DEVICE HAS A LONG USABLE LENGTH OF 220±22.0CM, SO IT CAN BE HARD TO DELIVER THE FORCE DURING DEPLOYMENT. OUTER SHEATH CAN BE STRETCHED AND DETACHED SO IT CAN CAUSE DEPLOYMENT FAILURE IF DEPLOYMENT WAS TRIED BY FORCE IN THIS SITUATION. HOWEVER, IT IS HARD TO IDENTIFY THE EXACT ROOT CAUSE SINCE IT IS HARD TO RECONSTRUCT THE SITUATION AT THE TIME OF PROCEDURE. IT IS IMPOSSIBLE TO IDENTIFY THE EXACT CAUSE BECAUSE THE DEVICE WAS NOT RETURNED. HOWEVER, BASED ON THE DESCRIPTION "WHEN THE PROCEDURE BEGAN, THE STENT DEPLOYED PREMATURELY" AND "CAUSING THE STENT TO BE FULLY RELEASED IN AN INCORRECT POSITION", IT IS IT IS CONSIDERED THAT DELIVERY SYSTEM WAS PRESSURED DUE TO PATIENT'S LESION DURING PROCEDURE AND DEPLOYMENT WAS TRIED IN THAT SITUATION. IT WAS HARD TO DEPLOY DUE TO PRESSURE SHEATH, AND STRONG RESISTANCE OCCURRED, AND THERE IS A POSSIBILITY WHEN MORE FORCE WAS USED, THE DELIVERY SYSTEM WAS BROKEN AND THE STENT WAS PLACED IN THE INCORRECT POSITION. IN ADDITION, THE SUSPECTED DEVICE IS UNCOVERED, THEREFORE FULLY DEPLOYED STENT CANNOT BE REMOVED OR REPOSITIONED. IT IS ASSUMED THE PLACED STENT COULD NOT BE REMOVED AND ANOTHER STENT COULD NOT BE PLACED DUE TO THE COMBINATION OF PLACED UNCOVERED STENT, STRONG STENOSIS AT THE PATIENT'S LESION, ETC. COMPLEXLY, AND COLOSTOMY WAS PERFORMED. TAEWOONG'S USER MANUAL OF THIS DEVICE STATES THE FOLLOWING. "REMOVAL OR REPOSITIONING OF FULLY DEPLOYED UNCOVERED/BARE STENTS IS CONTRAINDICATED" THIS SUSPECTED DEVICE IS NOT REGISTERED IN THE US BUT WE WILL CONTINUOUSLY MONITOR THE SAME OR SIMILAR CUSTOMER COMPLAINTS THROUGH ACCURATE ANALYSES.

Description of Event or Problem

ON (B)(6) 2026, DURING A PROCEDURE THE DOCTOR EXPERIENCED A STENT MALFUNCTION. THE STENT WAS INTRODUCED OVER A GUIDEWIRE AND DID NOT PRESENT ANY VISIBLE DEFECTS PRIOR TO USE. HOWEVER, WHEN THE PROCEDURE BEGAN, THE STENT DEPLOYED PREMATURELY. ALL STANDARD STEPS WERE FOLLOWED: THE SYSTEM WAS FLUSHED, UNLOCKED, AND DEPLOYMENT WAS ATTEMPTED AS PER USUAL PROTOCOL. DESPITE THIS, DURING DEPLOYMENT, PART OF THE DELIVERY SYSTEM BROKE, CAUSING THE STENT TO BE FULLY RELEASED IN AN INCORRECT POSITION. THE COLONOSCOPE WAS NOT EXCESSIVELY ANGULATED, AND THERE WERE NO VISIBLE KINKS OR ABNORMALITIES IN THE DELIVERY SYSTEM PRIOR TO USE. IN THE ATTACHED IMAGE, A SEPARATION IN THE DELIVERY SYSTEM CAN BE SEEN FOLLOWING THE FAILURE. A SECOND STENT WAS REQUIRED TO COMPLETE THE PROCEDURE. AS THE INITIAL STENT WAS UNCOVERED, IT DID NOT HAVE A RETRIEVAL STRING. AN ATTEMPT WAS MADE TO REMOVE IT USING GRASPING FORCEPS; HOWEVER, DUE TO THE STENOSIS, RETRIEVAL WAS UNSUCCESSFUL. AT THIS POINT, THE DOCTOR EXPRESSED CONCERN REGARDING THE MALFUNCTION AND REQUESTED PLACEMENT OF A SECOND STENT TO ATTEMPT TO RELIEVE THE STENOSIS. THIS SECOND ATTEMPT WAS UNSUCCESSFUL, AS THE POSITION OF THE FIRST STENT PREVENTED PROPER DEPLOYMENT OF THE SECOND DEVICE. AS A RESULT, THE PROCEDURE WAS CANCELLED WITH THE STENT REMAINING IN AN INCORRECT POSITION. A FURTHER ATTEMPT TO RETRIEVE THE STENT WAS MADE 72 HOURS LATER, BUT IT WAS ALSO UNSUCCESSFUL. THE PATIENT SUBSEQUENTLY REQUIRED A THIRD SURGICAL INTERVENTION, WHICH RESULTED IN A COLOSTOMY.