Soft artificial bladder with volume monitoring capabilities

Urinary bladder cancer is the tenth most common cancer in the world with an incidence of approximately 550,000 new cases each year [1]. Non-muscle invasive tumors are locally removed with trans urethral resection or chemotherapy, while invasive tumors (30% of cases) are generally treated with the surgical removal of the entire bladder and the urethra (radical cystectomy) to avoid recurrence [2]. Following cystectomy, uretero- cutaneostomy (i.e., urine drainage from the kidneys to an external container) or neobladder reconstruction with autologous intestine are possible solutions. Although they are standard clinical procedures, they present several complications including possible onset of infections, rupture of the neobladder, tumor recurrence, as well as low patient’s quality of life [3]. This scenario motivates the development of alternative solutions to restore bladder functions, i.e., urinary continence and controlled micturition. Over the years, researchers moved towards the development of fully implantable bioartificial [4] and artificial [5] bladder systems. Considering the Valsalva maneuver (i.e., abdominal torsion) as a possible voiding strategy, two functions are crucial for a complete bladder system: urine collection and fullness sensitivity. In this regard, some preliminary sensing systems have been proposed in literature. However, the solutions are closely related to specific and not bio-inspired geometries [5] or suitable only for small animals [6]. In this framework, we propose a novel biorobotic organ composed of a soft hexagonal-shaped artificial bladder (AB) coupled to a resistive textile sensors-based volume monitoring apparatus. The foldable structure of the AB together with the small thickness and flexibility of the embedded sensors make the system compact and suitable for implantation. The design and fabrication processes are here shown together with a preliminary validation of the sensorized AB.