Bladder ARFI (Acoustic Radiation Force Impulse) Study

Evaluation of Pediatric Urinary Bladder Wall Thickening and Fibrosis Using Acoustic Radiation Force Impulse (ARFI)-Derived Shear Wave Velocities

Urinary bladder fibrosis (thickening and scarring) is fairly uncommon in children. Traditionally, the presence of urinary bladder fibrosis has been confirmed directly with bladder biopsy or using urodynamic testing. In this study we will use ultrasound scanning and ARFI (acoustic radiation force impulse) wave velocities to potentially identify any urinary bladder wall fibrosis.

Urinary bladder fibrosis (thickening and scarring) is fairly uncommon in children. Traditionally, the presence of urinary bladder fibrosis has been confirmed directly with bladder biopsy or using urodynamic testing. We will use ultrasound ARFI (acoustic radiation force impulse)-derived shear wave velocities to potentially identify the presence of urinary bladder wall fibrosis. We hypothesize that shear wave velocities found within the bladder wall will increase with increasing evidence of fibrosis.

This is an ultrasound-based new technique using Acoustic Radiation Force Impulse (ARFI). Shear Wave speeds are derived using ARFI. During ultrasound scanning a sound wave is sent towards tissue. The tissue's movement in response to the wave is measured in Shear Wave Velocity, which can estimate tissue stiffness. This technique may help detect bladder wall thickness and fibrosis (thickening) in the urinary bladder of pediatric patients.

An ultrasound based scan uses ARFI, an acoustic radiation force impulse to estimate shear wave velocities during scanning of the urinary bladder. The research ultrasound scan lasts about 10 to 15 minutes.

Shear wave velocity VTQ, or Virtual Touch Quantification is a "point" method for measuring a tissue's stiffness. A stiffness value is obtained from only the area in which a region of interest is placed.

Shear Wave Velocity, VITQ, or Virtual Touch Tissue Imaging quantification is a color 2D method for measuring a tissues's stiffness. A color image (elastogram) of stiffness is acquired using this method. Then, one or more regions of interest can be placed in the area of interest on the elastogram. VITQ regions of interest are smaller than those used by VTQ.

Inclusion Criteria: 18 years of age or younger Have an order for urodynamic testing from your doctor Exclusion Criteria: Adults Unwilling to sign consent form