Manufacturing process for hydrogel vessel phantoms

Abstract

Phantoms mimicking special physiological processes of the human body are essential for evaluating prototypes of medical devices. Especially for thermometric MRI measurements, the temperature distribution in the brain needs to be simulated. Since this parameter is dependent on the tissue perfusion, a new hydrogel by MAGDASSIS et al. was evaluated in this work for building models with hollow artery structures. This hydrogel can be polymerized through UV-light due to the nanoparticles contained in it. Additionally, thermal parameters were measured and compared to human brain tissue. The indirect manufacturing of hydrogel phantoms showed good qualitative results for vessels with a diameter > 3 mm. In this process a 3D printed wax core was inserted in the hydrogel and the structure was then UV cured after molding. After curing the core was dissolved in an isopropanol bath. The thermal properties, obtained by the transient planesource- method, showed similar values compared to that of human brain tissue mentioned in literature. Further limitations in the manufacturing process needs to be overcome to use the indirect manufacture approach for smaller vessels of the brain.

Development of an Artificial Soft Solid Gel Using Gelatin Material for High-Quality Ultrasound Diagnosis

“…The conventional gel was formulated from propylene glycol (CH 3 CH COH CH 2 OH) with a density of 1.04 g/cm 3 , while the chemical formula of the gelatin was a combination of collagen, alkali, and protein (C 6 H 12 O 6 ), and its density was 1.2 g/cm 3 , respectively. The gelatin was higher in elastin than conventional gel due to its high density [25].…”

“…To obtain the elastin ratio corresponding to the conventional gel and gelatin material, the moisture rate (M) was calculated using Equation ( 3) [25]. The conventional gel was formulated from propylene glycol (CH 3 CH COH CH 2 OH) with a density of 1.04 g/cm 3 , while the chemical formula of the gelatin was a combination of collagen, alkali, and protein (C 6 H 12 O 6 ), and its density was 1.2 g/cm 3 , respectively.…”

“…The thermal conductivity values of the conventional gel and gelatin powder were 0.34 W/m-K and 0.55 W/m-K, respectively, with a temperature range of 70 [25,26]. Ultrasonic reflection (echo) is crucial for high-resolution monitoring [27].…”

“…As shown in Equation ( 12), the time value (T) in the horizontal zone was calculated by dividing that of the soft solid gel (x) by that of the American gel (y), resulting in a 1.2-fold increase. This calculation was performed by dividing the soft solid gel value by the corresponding ultrasonic gel value [25,26].…”