Controlled microrobotic navigation in the vascular system can revolutionize minimally invasive medical applications, such as targeted drug and gene delivery. Magnetically controlled surface microrollers have emerged as a promising microrobotic platform for controlled navigation in the circulatory system. Locomotion of micrororollers in strong flow velocities is a highly challenging task, which requires magnetic materials having strong magnetic actuation properties while being biocompatible. The L10‐FePt magnetic coating can achieve such requirements. Therefore, such coating has been integrated into 8 µm‐diameter surface microrollers and investigated the medical potential of the system from magnetic locomotion performance, biocompatibility, and medical imaging perspectives. The FePt coating significantly advanced the magnetic performance and biocompatibility of the microrollers compared to a previously used magnetic material, nickel. The FePt coating also allowed multimodal imaging of microrollers in magnetic resonance and photoacoustic imaging in ex vivo settings without additional contrast agents. Finally, FePt‐coated microrollers showed upstream locomotion ability against 4.5 cm s−1 average flow velocity with real‐time photoacoustic imaging, demonstrating the navigation control potential of microrollers in the circulatory system for future in vivo applications. Overall, L10‐FePt is conceived as the key material for image‐guided propulsion in the vascular system to perform future targeted medical interventions.

N-acetylcysteine (NAC) is a precursor of glutathione, a potent antioxidant, and a free radical scavenger. The beneficial effect of NAC on nervous system ischemia and ischemia/reperfusion models has been well documented. However, the effect of NAC on nervous system trauma remains less understood. Therefore, we aimed to investigate the therapeutic efficacy of NAC with an experimental closed head trauma model in rats. Thirty-six adult male Sprague-Dawley rats were randomly divided into three groups of 12 rats each: Group I (control), Group II (trauma-alone), and Group III (trauma+NAC treatment). In Groups II and III, a cranial impact was delivered to the skull from a height of 7 cm at a point just in front of the coronal suture and over the right hemisphere. Rats were sacrificed at 2 h (Subgroups I-A, II-A, and III-A) and 12 h (Subgroups I-B, II-B, and III-B) after the onset of injury. Brain tissues were removed for biochemical and histopathological investigation. The closed head trauma significantly increased tissue malondialdehyde (MDA) levels (P < 0.05), and significantly decreased tissue superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities (P < 0.05), but not tissue catalase (CAT) activity, when compared with controls. The administration of a single dose of NAC (150 mg/kg) 15 min after the trauma has shown protective effect via decreasing significantly the elevated MDA levels (P < 0.05) and also significantly (P < 0.05) increasing the reduced antioxidant enzyme (SOD and GPx) activities, except CAT activity. In the trauma-alone group, the neurons became extensively dark and degenerated into picnotic nuclei. The morphology of neurons in the NAC treatment group was well protected. The number of neurons in the trauma-alone group was significantly less than that of both the control and trauma+NAC treatment groups. In conclusion, the NAC treatment might be beneficial in preventing trauma-induced oxidative brain tissue damage, thus showing potential for clinical implications.

Magnetic resonance imaging (MRI) system–driven medical robotics is an emerging field that aims to use clinical MRI systems not only for medical imaging but also for actuation, localization, and control of medical robots. Submillimeter scale resolution of MR images for soft tissues combined with the electromagnetic gradient coil–based magnetic actuation available inside MR scanners can enable theranostic applications of medical robots for precise image‐guided minimally invasive interventions. MRI‐driven robotics typically does not introduce new MRI instrumentation for actuation but instead focuses on converting already available instrumentation for robotic purposes. To use the advantages of this technology, various medical devices such as untethered mobile magnetic robots and tethered active catheters have been designed to be powered magnetically inside MRI systems. Herein, the state‐of‐the‐art progress, challenges, and future directions of MRI‐driven medical robotic systems are reviewed.

Magnetic resonance imaging (MRI) scanners have recently been used for magnetic actuation of robots for minimally invasive medical operations. Due to MRI's high soft‐tissue selectivity, it is possible to obtain 3D images of hard‐to‐reach cavities in the human body, where the wireless miniature magnetic robots powered by MRI could be employed for high‐precision targeted operations, such as drug delivery, stem cell therapy, and hyperthermia. However, the state‐of‐the‐art fast magnetic robot‐tracking methods in MRI are limited above millimeter‐size scale, which restricts the potential target regions inside the human body. Herein, a fast 1D projection‐based MRI approach that can track magnetic particles down to 300 μm diameter (1.17 × 10−2 emu) is reported. The technique reduces the trackable magnetic particle size in MRI‐powered navigation fivefold compared with the previous fast‐tracking methods. A closed‐loop MRI‐powered navigation with 0.78 ± 0.03 mm trajectory‐following accuracy in millimeter‐sized in vitro 2D channels and a 3D cavity setup using the tracking method is demonstrated. Furthermore, the feasibility of submillimeter magnetic robot tracking in ex vivo pig kidneys (N = 2) with a 3.6 ± 1.1 mm accuracy is demonstrated. Such a fast submillimeter‐scale mobile robot‐tracking approach can unlock new opportunities in minimally invasive medical operations.

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A neurosurgical laboratory training model is designed for residents of neurosurgery to handle surgical microscopes and microneurosurgical instruments. The material consists of a one-year-old fresh cadaveric sheep cranium. A four-step approach was designed to simulate microneurosurgical dissection along the posterior fossa cisterns, and to dissect cranial nerves emerging from the brain stem. We conclude that this laboratory training model is useful to allow trainees to gain experience with the general use of an operating microscope, and familiarity with handling cranial nerves.