The sodium hyaluronate microspheres fabricated by solution drying for transcatheter arterial embolization.

Transcatheter arterial embolization (TAE) is an effective therapeutic method for several clinical ailments. Interminably, the polymer microsphere is reflected as one of the idyllic embolic materials due to the exceptional biocompatibility and microcatheter administration. Herein, a one-step solution drying technique was first developed to fabricate sodium hyaluronate microspheres cross-linked by 1,4-Butanediol diglycidyl ether (BDDE) for transcatheter arterial embolization. The monodispersed sodium hyaluronate microspheres with a diameter range from 350 to 900 µm were obtained by this technique without any complicated instrument and extra surfactant, which is consistent with the standard distribution of commercial embolic microspheres. Additionally, barium sulfate (BaSO4) nanoparticles were introduced as the contrasting mediator to improve the X-ray imaging capability of sodium hyaluronate microspheres and then achieve a real-time trace and discernibility in vivo. A significantly embellished mechanical strength and compressibility for BaSO4@SH microspheres were also observed. In vitro biocompatibility evaluation revealed non-cytotoxicity and great hemocompatibility of BaSO4@SH microspheres. Moreover, the histopathological analysis and computed tomography images of the embolized kidney confirmed the effective occlude blood and in vivo visibility capability of BaSO4@SH microspheres for at least 4 weeks. Conclusively, such an inexpensive and environmentally friendly technique for fabricating BaSO4@SH microspheres might be a promising strategy to promote the development of transcatheter arterial embolization in practice.

Enhancing integral imaging performance using time-multiplexed convergent backlight.

A method to enhance the performance of an integral imaging system is demonstrated using the time-multiplexed convergent backlight technique. The backlight increases the space bandwidth of the integral imaging system. As a result, the resolution, depth of field, and viewing angle of the integral imaging system are increased simultaneously. The cross-talk noise is also decreased without using any optical barrier. One part of the added space bandwidth comes from the optimized illumination. The other part is converted from the time bandwidth of the system by time-multiplexing. The time-multiplexed convergent backlight modulates the direction of the backlight in time sequence to illuminate the elemental images. Then, the elemental images synthesize the 3D images using a microlens array. An elemental images rendering method using a conjugate pinhole camera and pinhole projector model is designed to dynamically match the illumination direction. The rendering method eliminates the distortion and maximizes the viewing angle and viewing zone. A field programmable gate array (FPGA)-based controller is used to manage and synchronize the time sequence of the backlight and the display devices. Using this technique, high-performance 3D images are realized. Comparison experiments of the integral imaging system using diffused backlight and convergent backlight are performed. The results show the effectiveness of the proposed technique.