Systemic drug administration often causes off-target effects, limiting the efficacy of advanced therapies. Targeted drug delivery approaches increase local drug concentrations at the diseased site while minimizing systemic drug exposure. We present a magnetically guided microrobotic drug delivery platform capable of precise navigation under physiological conditions. This platform integrates a clinical electromagnetic navigation system, a custom-designed release catheter, and a dissolvable capsule for accurate therapeutic delivery. In vitro tests showed precise navigation in human vasculature models, and in vivo experiments confirmed tracking under fluoroscopy and successful navigation in large animal models. The microrobot balances magnetic material concentration, contrast agent loading, and therapeutic drug capacity, offering a promising solution for precise targeted drug delivery.
Introduction: To compare tocolysis with magnesium sulfate versus atosiban regarding the occurrence of short-term preterm labor and maternal side effects during and after open fetal myelomeningocele (MMC) repair. Material and Methods: A prospective nonrandomized cohort study was performed including 30 fetal MMC cases. The first 15 cases (group 1) received magnesium sulfate according to the MOMS protocol. In the following 15 cases (group 2), magnesium sulfate was substituted by atosiban. Chorioamniotic membrane separation (CMS), premature prelabor rupture of the fetal membranes (PPROM), preterm delivery <3 weeks after fetal MMC repair, and maternal complications due to the tocolytic medication were the major endpoints. Results: In both groups, one CMS but no PPROM was diagnosed <3 weeks after fetal MMC repair. One patient of group 2 delivered <3 weeks after fetal MMC repair because of an intraoperative placental abruption at 25 weeks. All women of group 1 showed an electrolyte imbalance during magnesium sulfate administration. One woman of group 1 developed several episodes of a third-degree atrioventricular block within the first 3 days after fetal surgery. Lethargy was found in all women during magnesium sulfate therapy. No maternal side effects were found under atosiban. Discussion: The use of atosiban resulted in an almost identical short-term uterine outcome without any serious maternal complications as seen when magnesium sulfate was given. Thus, the authors suggest using atosiban instead of magnesium sulfate in the context of open fetal surgery.
12 January 2021 in Pediatric Surgery International
Microtia is a congenital disorder that manifests as a malformation of the external ear leading to psychosocial problems in affected children. Here, we present a tissue-engineered treatment approach based on a bioprinted autologous auricular cartilage construct (EarCartilage) combined with a bioengineered human pigmented and prevascularized dermo-epidermal skin substitute (EarSkin) tested in immunocompromised rats. We confirmed that human-engineered blood capillaries of EarSkin connected to the recipient’s vasculature within 1 week, enabling rapid blood perfusion and epidermal maturation. Bioengineered EarSkin displayed a stratified epidermis containing mature keratinocytes and melanocytes. The latter resided within the basal layer of the epidermis and efficiently restored the skin color. Further, in vivo tests demonstrated favorable mechanical stability of EarCartilage along with enhanced extracellular matrix deposition. In conclusion, EarCartilage combined with EarSkin represents a novel approach for the treatment of microtia with the potential to circumvent existing limitations and improve the aesthetic outcome of microtia reconstruction.
3 February 2022 in IEEE Transactions on Medical Robotics and Bionics
Spina bifida is a congenital defect that occurs on the vertebral spine of a fetus. The most severe form causes exposure of the spinal cord and spinal nerve and has important repercussions on the life of the newborn child. Current prenatal operative procedures require laparotomy of the abdomen as well as hysterotomy of the uterus, which can result in severe consequences and risks for the mother. Here, we propose a robotically assisted endoscopic procedure based on magnetically steerable catheters to treat spina bifida defects in a minimally invasive way. The procedure can be performed in a fully remote manner using magnetic guidance and a haptic controller. Four custom magnetic catheter designs are presented to image, sever, grasp and close the lesion on the fetus back. We demonstrate our approach in vitro using phantom models of the abdomen, the uterus, and the defected fetus.