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Implantable Bladder Sensors: A Methodological Review.

Dakurah MN, Koo C, Choi W, Joung YH - Int Neurourol J (2015)

Bottom Line: With the recent advances in microfabrication, the size of implantable bladder sensors has been significantly reduced.However, microfabricated sensors face hostility from the bladder environment and require surgical intervention for implantation inside the bladder.We also discuss some possible improvements/emerging trends in the design of an implantable bladder sensor.

View Article: PubMed Central - PubMed

Affiliation: Department of Electronics and Control Engineering, Hanbat National University, Daejeon, Korea.

ABSTRACT
The loss of urinary bladder control/sensation, also known as urinary incontinence (UI), is a common clinical problem in autistic children, diabetics, and the elderly. UI not only causes discomfort for patients but may also lead to kidney failure, infections, and even death. The increase of bladder urine volume/pressure above normal ranges without sensation of UI patients necessitates the need for bladder sensors. Currently, a catheter-based sensor is introduced directly through the urethra into the bladder to measure pressure variations. Unfortunately, this method is inaccurate because measurement is affected by disturbances in catheter lines as well as delays in response time owing to the inertia of urine inside the bladder. Moreover, this technique can cause infection during prolonged use; hence, it is only suitable for short-term measurement. Development of discrete wireless implantable sensors to measure bladder volume/pressure would allow for long-term monitoring within the bladder, while maintaining the patient's quality of life. With the recent advances in microfabrication, the size of implantable bladder sensors has been significantly reduced. However, microfabricated sensors face hostility from the bladder environment and require surgical intervention for implantation inside the bladder. Here, we explore the various types of implantable bladder sensors and current efforts to solve issues like hermeticity, biocompatibility, drift, telemetry, power, and compatibility issues with popular imaging tools such as computed tomography and magnetic resonance imaging. We also discuss some possible improvements/emerging trends in the design of an implantable bladder sensor.

No MeSH data available.


Related in: MedlinePlus

An implantable bladder pressure sensor using PZT as energy source where (A) an acoustic receiver (PZT cantilever) and rectifier circuitry are assembled on a glass substrate; (B) an acrylic holder, proof of mass, and antenna/sensor coil are added; (C) the assembled parts are inserted into a glass tube and an acrylic lid is attached; and (D) the inductive sensor with PDMS membrane and ferrite core are added. Adapted from Kim A, et al. IEEE Trans Biomed Eng 2014;61:2209-17 [61], with permission of the Institute of Electrical and Electronics Engineers. RF, radio frequency; PZT, piezoelectric lead zirconat titanate; PDMS, polydimethylsiloxane.
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f2-inj-19-3-133: An implantable bladder pressure sensor using PZT as energy source where (A) an acoustic receiver (PZT cantilever) and rectifier circuitry are assembled on a glass substrate; (B) an acrylic holder, proof of mass, and antenna/sensor coil are added; (C) the assembled parts are inserted into a glass tube and an acrylic lid is attached; and (D) the inductive sensor with PDMS membrane and ferrite core are added. Adapted from Kim A, et al. IEEE Trans Biomed Eng 2014;61:2209-17 [61], with permission of the Institute of Electrical and Electronics Engineers. RF, radio frequency; PZT, piezoelectric lead zirconat titanate; PDMS, polydimethylsiloxane.

Mentions: Piezoelectric ceramic materials such as lead zirconate titanate (PZTs) could be an alternative means of harvesting energy to power implantable bladder sensors. Kim et al. [61] used an acoustic signal generated by an external speaker to cause an implanted piezoelectric cantilever, connected to a pressure sensor within the bladder, to vibrate at its resonant frequency as shown in Fig. 2. The low frequency of the acoustic signal allowed it to be transported through the body to the PZT with minimal signal loss, with no concerns of orientation or alignment related effects. This particular technology eliminates the alignment and distance issues associated with RF-based telemetry and simplifies implanted sensor design by removing the need for a sophisticated onboard receiver system.


Implantable Bladder Sensors: A Methodological Review.

Dakurah MN, Koo C, Choi W, Joung YH - Int Neurourol J (2015)

An implantable bladder pressure sensor using PZT as energy source where (A) an acoustic receiver (PZT cantilever) and rectifier circuitry are assembled on a glass substrate; (B) an acrylic holder, proof of mass, and antenna/sensor coil are added; (C) the assembled parts are inserted into a glass tube and an acrylic lid is attached; and (D) the inductive sensor with PDMS membrane and ferrite core are added. Adapted from Kim A, et al. IEEE Trans Biomed Eng 2014;61:2209-17 [61], with permission of the Institute of Electrical and Electronics Engineers. RF, radio frequency; PZT, piezoelectric lead zirconat titanate; PDMS, polydimethylsiloxane.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4582084&req=5

f2-inj-19-3-133: An implantable bladder pressure sensor using PZT as energy source where (A) an acoustic receiver (PZT cantilever) and rectifier circuitry are assembled on a glass substrate; (B) an acrylic holder, proof of mass, and antenna/sensor coil are added; (C) the assembled parts are inserted into a glass tube and an acrylic lid is attached; and (D) the inductive sensor with PDMS membrane and ferrite core are added. Adapted from Kim A, et al. IEEE Trans Biomed Eng 2014;61:2209-17 [61], with permission of the Institute of Electrical and Electronics Engineers. RF, radio frequency; PZT, piezoelectric lead zirconat titanate; PDMS, polydimethylsiloxane.
Mentions: Piezoelectric ceramic materials such as lead zirconate titanate (PZTs) could be an alternative means of harvesting energy to power implantable bladder sensors. Kim et al. [61] used an acoustic signal generated by an external speaker to cause an implanted piezoelectric cantilever, connected to a pressure sensor within the bladder, to vibrate at its resonant frequency as shown in Fig. 2. The low frequency of the acoustic signal allowed it to be transported through the body to the PZT with minimal signal loss, with no concerns of orientation or alignment related effects. This particular technology eliminates the alignment and distance issues associated with RF-based telemetry and simplifies implanted sensor design by removing the need for a sophisticated onboard receiver system.

Bottom Line: With the recent advances in microfabrication, the size of implantable bladder sensors has been significantly reduced.However, microfabricated sensors face hostility from the bladder environment and require surgical intervention for implantation inside the bladder.We also discuss some possible improvements/emerging trends in the design of an implantable bladder sensor.

View Article: PubMed Central - PubMed

Affiliation: Department of Electronics and Control Engineering, Hanbat National University, Daejeon, Korea.

ABSTRACT
The loss of urinary bladder control/sensation, also known as urinary incontinence (UI), is a common clinical problem in autistic children, diabetics, and the elderly. UI not only causes discomfort for patients but may also lead to kidney failure, infections, and even death. The increase of bladder urine volume/pressure above normal ranges without sensation of UI patients necessitates the need for bladder sensors. Currently, a catheter-based sensor is introduced directly through the urethra into the bladder to measure pressure variations. Unfortunately, this method is inaccurate because measurement is affected by disturbances in catheter lines as well as delays in response time owing to the inertia of urine inside the bladder. Moreover, this technique can cause infection during prolonged use; hence, it is only suitable for short-term measurement. Development of discrete wireless implantable sensors to measure bladder volume/pressure would allow for long-term monitoring within the bladder, while maintaining the patient's quality of life. With the recent advances in microfabrication, the size of implantable bladder sensors has been significantly reduced. However, microfabricated sensors face hostility from the bladder environment and require surgical intervention for implantation inside the bladder. Here, we explore the various types of implantable bladder sensors and current efforts to solve issues like hermeticity, biocompatibility, drift, telemetry, power, and compatibility issues with popular imaging tools such as computed tomography and magnetic resonance imaging. We also discuss some possible improvements/emerging trends in the design of an implantable bladder sensor.

No MeSH data available.


Related in: MedlinePlus