From lab to market: IISc team and surgeons develop dissolvable stent to reduce second surgery

BENGALURU: A small dissolving tube developed by a Bengaluru lab is taking a step closer to hospital use, offering a way to avoid repeat surgeries after major abdominal surgeries.The device, called the ‘Asthana Stent’, is the result of a collaboration between Sonal Asthana, a liver transplant surgeon at Aster CMI Hospital, and researchers led by Kaushik Chatterjee, Department of Materials Engineering and Bioengineering, IISc.It has now been licensed to Advanced Medtech Solutions Private Limited under an Indian patent, marking the transition from a laboratory prototype to a product that can enter the operating room.The idea started with recurring problems after liver transplants. The surgeon must connect the bile duct, a delicate connection that can leak or become narrowed later. These complications affect 11% to 40% of patients and often require additional surgery to repair.

Existing solutions rely on plastic tubes or stents to keep the duct open while it heals. But these are trade-offs. Some protrude outside the body and require careful management. Others remain inside but must be removed later through additional procedures, adding cost and risk.“The new stent takes a different approach. It is made from polydioxanone (PDS), a biodegradable polymer already used in dissolvable surgical sutures. Once placed in the body, it keeps the catheter open for about six weeks before gradually breaking down and being absorbed. No removal is required,” the team said.Turning this idea into a working device required engineering work by Thaseeb Rehman from IISc’s Department of Materials Engineering and Saswat Choudhury from the Department of Bioengineering. The team designed the tube to stay open under pressure and uses surface ridges and Velcro-like hooks to resist migration, while a flexible middle section allows for placement even if the tube opening is misaligned. Tiny radiopaque markers allow doctors to track them using X-rays.The researchers said: “Tests showed that the stent can withstand pressures of more than 16 Newtons, much higher than those experienced by bile ducts. It also maintained its structure in laboratory conditions and in human bile for more than six weeks, covering the critical healing window.”With the technology now licensed, the focus turns to manufacturing and approval. The company will be subject to regulatory inspections framed by the Central Drugs Standard Control Organization (CDSCO). The project is also supported by the Indian Council of Medical Research (ICMR).If approved, the stent would be used during surgery and would be available in a variety of sizes. For patients, the benefits are simple: one surgery instead of two, and less chance of complications after going home.