Aims Long-term urodynamics are required because bladder-emptying disorders are often not clearly revealed by conventional urodynamics. Patients with severe clinical overactive bladder symptoms, for instance, often show normal results. This may be due to the short evaluation time and psychological factors that complicate conventional urodynamics. This study aimed to develop an ambulatory three-component urodynamic measurement system that is easy to operate, registers urodynamic parameters for several days, and has no negative impact on the patient. Methods We developed an intravesical capsule combined with a hand-held device to register voiding desire and micturition, and an alarm pad device that detects urine loss. Recently, the intravesical capsule and its proven function were detailed in the literature. Here, we present detailed in vitro results using a female bladder model. The flexible capsule was C-shaped to minimize the risk of expulsion from the bladder during micturition. Results of biocompatibility evaluation of the intravesical capsule, which is called Wille Capsule (WiCa) are described. Results The WiCa with an oval nose and a maximum outer diameter of 5.5 mm was easily inserted through a 25-French cystoscope. Removing the WiCa by grasping the nose using the female model with bladder was easily conducted. Expulsion of the WiCa during voiding was avoided through a novel C-shaped device design. Based on in vitro cytotoxicity studies, the capsule is a promising and safe device. Conclusion Our novel system is an innovative minimally-invasive tool for accurate long-term urodynamic measurement, and does not require inserting a transurethral catheter.
References
[1]
Abrams P (2003) Describing bladder storage function: overactive bladder syndrome and detrusor overactivity. Urology 62: 28–37.
[2]
Digesu GA, Khullar V, Cardozo L, Salvatore S (2003) Overactive bladder symptoms: do we need urodynamics? Neurourol.Urodyn. 22: 105–108.
[3]
Hashim H, Abrams P (2006) Is the bladder a reliable witness for predicting detrusor overactivity? J.Urol. 175: 191–194.
[4]
Schnakenberg U, Kruger C, Pfeffer JG, Mokwa W, von Bogel G, et al. (2002) Transponder system for non-invasive measurement of intravascular pressure. Biomed.Tech.(Berl) 47 Suppl 1 Pt 1: 191–193.
[5]
Clasbrummel B, Muhr G (2005) Mikro- und Nanosystemtechnik – medizintechnologische Aspekte am Beispiel eines Blasendrucksensors. Chir Gastroenterol 21: 38–42.
[6]
Wang C-C, Huang C-C (2008) A Mini-Invasive Long-Term Bladder Urine Pressure Measurement ASIC and System. IEEE Transactions on Biomedical Circuits and Systems 2: 44–49.
[7]
Wille S, Tenholte D, Engelmann U (2013) A System for Long-term Urodynamic Studies Without Catheters. Eur.Urol. 63: 966–968.
[8]
Vijayananthan A, Nawawi O (2008) The importance of Good Clinical Practice guidelines and its role in clinical trials. Biomed.Imaging Interv.J. 4: 5–7.
[9]
Jourand P, Puers R (2010) The BladderPill: An in-body system logging bladder pressure. Sensors and Actuators A 162: 160–166.
[10]
Braden M, Wright PS, Parker S (1995) Soft lining materials–a review. Eur.J.Prosthodont.Restor.Dent. 3: 163–174.
[11]
Radley SC, Rosario DJ, Chapple CR, Farkas AG (2001) Conventional and ambulatory urodynamic findings in women with symptoms suggestive of bladder overactivity. J.Urol. 166: 2253–2258.
[12]
Pizzoferrato A, Ciapetti G, Stea S, Cenni E, Arciola CR, et al. (1994) Cell culture methods for testing biocompatibility. Clin.Mater. 15: 173–190.
[13]
BMP GmbH, Investigation report B0343/12 on Cytotoxicity (2012) 1–24.
[14]
BMP GmbH, Investigation report B0133/13 on Cytotoxicity (2013) 1–25.
[15]
Belanger MC, Marois Y, Roy R, Mehri Y, Wagner E, et al. (2000) Selection of a polyurethane membrane for the manufacture of ventricles for a totally implantable artificial heart: blood compatibility and biocompatibility studies. Artif.Organs 24: 879–888.
