Evaluation of Compliance of Poly (vinyl alcohol) Hydrogel for Development of Arterial Biomodeling

A new polyvinyl alcohol hydrogel vascular model (KEZLEX) for microvascular anastomosis training

“…Both our pilot experiments and simulations of variable vascular pathologies by other groups[1217] have shown that the PVA hydrogel vessel models exhibited similar mechanical properties (surface friction and elasticity) and visibilities (transparence and compatibility with staining to blue dye) to real arteries [Figure 2] that may be accepted as a good biomaterial for practicing microsurgical anastomosis. The prosthetic materials need to be kept moist by intermittent spraying with water to prevent structures from drying out during practice.…”

“…The vascular substitute [ Figure 1 ] was processed and extracted from PVA hydrogel by laser sintering technique to provide 1.0–3.0mm diameter (available for 0.5-mm pitch), 6–8cm long tubes that are qualitatively similar to human donor and recipient arteries for various bypass surgeries based on three-dimensional computed tomography/magnetic resonance imaging scanning data reconstruction using visible human data set and vessel casts. Both our pilot experiments and simulations of variable vascular pathologies by other groups[ 12 17 ] have shown that the PVA hydrogel vessel models exhibited similar mechanical properties (surface friction and elasticity) and visibilities (transparence and compatibility with staining to blue dye) to real arteries [ Figure 2 ] that may be accepted as a good biomaterial for practicing microsurgical anastomosis. The prosthetic materials need to be kept moist by intermittent spraying with water to prevent structures from drying out during practice.…”

“…In fact, recent data suggest that the PVA hydrogel vascular model has more similar pulsatility of vascular lumen to a real cerebral vasculature when compared to silicone,[ 17 ] although the compliance calculated from the diameter–pressure curve still needs room for improving. [ 12 ] In terms of the ability of structural modification in various sizes and shapes with KEZLEX technology[ 11 ] and of stiffness/elasticity of PVA hydrogel closer to the human soft tissue than silicone tube,[ 17 ] our model may have some advantages over existing “relatively harder” synthetic materials made from polyvinyl chloride[ 20 ] and polyurethane,[ 15 16 ] although direct comparison has not yet been performed.…”

Blood flow imaging using singular value decomposition filter during high-intensity focused ultrasound exposure

“…A blood flow phantom made of poly-vinyl alcohol with a 4 mm diameter cylindrical cavity was used as the object for HIFU exposure. 25) The phantom containing cellulose as ultrasonic scatterers was set in the water tank so that the HIFU geometric focus was located in the cavity. The direction of the cylindrical cavity was set at an angle of 45°to the probe surface and a blood-mimicking fluid (ATS Laboratories, Doppler test fluid model 707) was flown through it at a steady flow velocity of 20 cm s −1 .…”

Singular value decomposition of received ultrasound signal to separate tissue, blood flow, and cavitation signals

“…The size of the phantom was 145 (width) × 60 (depth) × 45 (height) mm 3 . The phantom, made of poly-(vinyl alcohol) (PVA) gel containing cellulose as ultrasonic scatterers, 32) was set at the focal point of HIFU. The direction of the cylindrical cavity was set at a 45°angle to the probe surface and a blood-mimicking fluid (ATS Laboratories, Doppler test fluid model 707) was flowed through.…”