Medical Microrobots.

Scientists around the world have long aimed to produce miniature robots that can be controlled inside the human body to aid doctors in identifying and treating diseases. Such microrobots hold the potential to access hard-to-reach areas of the body through the natural lumina. Wireless access has the potential to overcome drawbacks of systemic therapy, as well as to enable completely new minimally invasive procedures. The aim of this review is fourfold: first, to provide a collection of valuable anatomical and physiological information on the target working environments together with engineering tools for the design of medical microrobots; second, to provide a comprehensive updated survey of the technological state of the art in relevant classes of medical microrobots; third, to analyze currently available tracking and closed-loop control strategies compatible with the in-body environment; and fourth, to explore the challenges still in place, to steer and inspire future research.

Limitation of life sustaining therapy in disorders of consciousness: ethics and practice.

Clinical conversations surrounding the continuation or limitation of life-sustaining therapies (LLST) are both challenging and tragically necessary for patients with disorders of consciousness (DoC) following severe brain injury. Divergent cultural, philosophical and religious perspectives contribute to vast heterogeneity in clinical approaches to LLST-as reflected in regional differences and inter-clinician variability. Here we provide an ethical analysis of factors that inform LLST decisions among patients with DoC. We begin by introducing the clinical and ethical challenge and clarifying the distinction between withdrawing and withholding life-sustaining therapy. We then describe relevant factors that influence LLST decision-making including diagnostic and prognostic uncertainty, perception of pain, defining a 'good' outcome, and the role of clinicians. In concluding sections, we explore global variation in LLST practices as they pertain to patients with DoC and examine the impact of cultural and religious perspectives on approaches to LLST. Understanding and respecting the cultural and religious perspectives of patients and surrogates is essential to protecting patient autonomy and advancing goal-concordant care during critical moments of medical decision-making involving patients with DoC.

Shape-constrained deformable brain segmentation: Methods and quantitative validation.

MRI-guided neuro interventions require rapid, accurate, and reproducible segmentation of anatomical brain structures for identification of targets during surgical procedures and post-surgical evaluation of intervention efficiency. Segmentation algorithms must be validated and cleared for clinical use. This work introduces a methodology for shape-constrained deformable brain segmentation, describes the quantitative validation used for its clinical clearance, and presents a comparison with manual expert segmentation and FreeSurfer, an open source software for neuroimaging data analysis. ClearPoint Maestro is software for fully-automatic brain segmentation from T1-weighted MRI that combines a shape-constrained deformable brain model with voxel-wise tissue segmentation within the cerebral hemispheres and the cerebellum. The performance of the segmentation was validated in terms of accuracy and reproducibility. Segmentation accuracy was evaluated with respect to training data and independently traced ground truth. Segmentation reproducibility was quantified and compared with manual expert segmentation and FreeSurfer. Quantitative reproducibility analysis indicates superior performance compared to both manual expert segmentation and FreeSurfer. The shape-constrained methodology results in accurate and highly reproducible segmentation. Inherent point based-correspondence provides consistent target identification ideal for MRI-guided neuro interventions.

Neoadjuvant nivolumab plus chemotherapy in resectable non-small-cell lung cancer in Japanese patients from CheckMate 816.

In the open-label, phase III CheckMate 816 study (NCT02998528), neoadjuvant nivolumab plus chemotherapy demonstrated statistically significant improvements in event-free survival (EFS) and pathological complete response (pCR) versus chemotherapy alone in patients with resectable non-small-cell lung cancer (NSCLC). Here we report efficacy and safety outcomes in the Japanese subpopulation. Patients with stage IB-IIIA, resectable NSCLC were randomized 1:1 to nivolumab plus chemotherapy or chemotherapy alone for three cycles before undergoing definitive surgery within 6 weeks of completing neoadjuvant treatment. The primary end-points (EFS and pCR) and safety were assessed in patients enrolled at 16 centers in Japan. Of the Japanese patients randomized, 93.9% (31/33) in the nivolumab plus chemotherapy arm and 82.9% (29/35) in the chemotherapy arm underwent surgery. At 21.5 months' minimum follow-up, median EFS was 30.6 months (95% confidence interval [CI], 16.8-not reached [NR]) with nivolumab plus chemotherapy versus 19.6 months (95% CI, 8.5-NR) with chemotherapy; hazard ratio, 0.60 (95% CI, 0.30-1.24). The pCR rate was 30.3% (95% CI, 15.6-48.7) versus 5.7% (95% CI, 0.7-19.2), respectively; odds ratio, 7.17 (95% CI, 1.44-35.85). Grade 3/4 treatment-related adverse events were reported in 59.4% versus 42.9% of patients, respectively, with no new safety signals identified. Neoadjuvant nivolumab plus chemotherapy resulted in longer EFS and a higher pCR rate versus chemotherapy alone in Japanese patients, consistent with findings in the global population. These data support nivolumab plus chemotherapy as a neoadjuvant treatment option in Japanese patients with resectable NSCLC.

Minimally invasive surgical therapies for benign prostatic hyperplasia in the geriatric population: A systematic review.

BACKGROUND: Geriatric patients, prone to adverse events (AEs) and low compliance with drugs, may benefit from minimally invasive surgical therapies (MISTs) for managing benign prostatic hyperplasia (BPH). We evaluated the efficacy, safety, and procedural characteristics of MISTs in geriatric patients with BPH. METHODS: PubMed/MEDLINE database was systematically searched for relevant articles through October 1, 2023. Eligible studies focused on geriatric patients (≥65 years) with BPH who were treated with MISTs and evaluated follow-up surgical, micturition, and/or sexual outcomes. Studies were included if there was separate reporting for age subgroups ≥65 years, or if the mean age minus standard deviation was ≥65 years, or if the first quartile was ≥65 years. RESULTS: Out of 292 screened studies, 32 (N = 3972 patients) met inclusion criteria and assessed prostatic artery embolization (PAE), Rezum, GreenLight, holmium laser enucleation of the prostate (HoLEP), thulium laser enucleation of the prostate (ThuLEP), diode laser enucleation of the prostate (DiLEP), and Aquablation. Except for Rezum, all MISTs required a planned overnight stay. While PAE and Rezum could be performed under local anesthesia, the other MISTs needed general or spinal anesthesia. Postoperative catheterization duration was longest for PAE (median 14 days) and Rezum (21 days) and shortest for GreenLight (1.9 days). At 12 months postoperatively, all MISTs exhibited significant percent changes in International Prostate Symptom Score (median -69.9%) and quality of life (median -72.5%). Clavien-Dindo Grade 1 AEs ranged widely, with PAE (5.8%-36.8%), Rezum (0%-62.1%), and GreenLight (0%-67.6%) having the largest range, and HoLEP (0%-9.5%), ThuLEP (2%-6.9%), and DiLEP (5%-17.5%) having the smallest. PAE, Rezum, DiLEP, and Aquablation reported no significant changes in the International Index of Erectile Function. CONCLUSIONS: Although all the MISTs reviewed in this study effectively treat BPH in geriatric patients, differences in procedural characteristics and safety profiles across MISTs were considerable. Physicians should use shared decision-making processes, considering risks and patient characteristics, when choosing a suitable treatment option for their patients.

Total robotic liver transplant: the final frontier of minimally invasive surgery.

The use of robotic surgery in transplantation is increasing; however, robotic liver transplantation (RLT) remains a challenging undertaking. To our knowledge, this is a report of the first RLT in North America and the first RLT using a whole graft from a deceased donor in the world. This paper describes the preparation leading to the RLT and the surgical technique of the operation. The operation was performed in a 62-year-old man with hepatitis C cirrhosis and hepatocellular carcinoma with a native Model for End-Stage Liver Disease score of 10. The total console time for the operation was 8 hours 30 minutes, and the transplant hepatectomy took 3 hours 30 minutes. Warm ischemia time was 77 minutes. Biliary reconstruction was performed in a primary end-to-end fashion and took 19 minutes to complete. The patient had an uneventful recovery without early allograft dysfunction or surgical complications and continues to do well after 6-months follow-up. This paper demonstrates the feasibility of this operation in highly selected patients with chronic liver disease. Additional experience is required to fully understand the role of RLT in the future of transplant surgery. Narrated video is available at https://youtu.be/TkjDwLryd3I.

How well do neural signatures of resting-state EEG detect consciousness? A large-scale clinical study.

The assessment of consciousness states, especially distinguishing minimally conscious states (MCS) from unresponsive wakefulness states (UWS), constitutes a pivotal role in clinical therapies. Despite that numerous neural signatures of consciousness have been proposed, the effectiveness and reliability of such signatures for clinical consciousness assessment still remains an intense debate. Through a comprehensive review of the literature, inconsistent findings are observed about the effectiveness of diverse neural signatures. Notably, the majority of existing studies have evaluated neural signatures on a limited number of subjects (usually below 30), which may result in uncertain conclusions due to small data bias. This study presents a systematic evaluation of neural signatures with large-scale clinical resting-state electroencephalography (EEG) signals containing 99 UWS, 129 MCS, 36 emergence from the minimally conscious state, and 32 healthy subjects (296 total) collected over 3 years. A total of 380 EEG-based metrics for consciousness detection, including spectrum features, nonlinear measures, functional connectivity, and graph-based measures, are summarized and evaluated. To further mitigate the effect of data bias, the evaluation is performed with bootstrap sampling so that reliable measures can be obtained. The results of this study suggest that relative power in alpha and delta serve as dependable indicators of consciousness. With the MCS group, there is a notable increase in the phase lag index-related connectivity measures and enhanced functional connectivity between brain regions in comparison to the UWS group. A combination of features enables the development of an automatic detector of conscious states.

Minimally invasive surgeries for spontaneous hypertensive intracerebral hemorrhage (MISICH): a multicenter randomized controlled trial.

BACKGROUND: Intracerebral hemorrhage (ICH) is a common stroke type with high morbidity and mortality. There are mainly three surgical methods for treating ICH. Unfortunately, thus far, no specific surgical method has been proven to be the most effective. We carried out this study to investigate whether minimally invasive surgeries with endoscopic surgery or stereotactic aspiration (frameless navigated aspiration) will improve functional outcomes in patients with supratentorial ICH compared with small-bone flap craniotomy. METHODS: In this parallel-group multicenter randomized controlled trial conducted at 16 centers, patients with supratentorial hypertensive ICH were randomized to receive endoscopic surgery, stereotactic aspiration, or craniotomy at a 1:1:1 ratio from July 2016 to June 2022. The follow-up duration was 6 months. Patients were randomized to receive endoscopic evacuation, stereotactic aspiration, or small-bone flap craniotomy. The primary outcome was favorable functional outcome, defined as the proportion of patients who achieved a modified Rankin scale (mRS) score of 0-2 at the 6-month follow-up. RESULTS: A total of 733 patients were randomly allocated to three groups: 243 to the endoscopy group, 247 to the aspiration group, and 243 to the craniotomy group. Finally, 721 patients (239 in the endoscopy group, 246 in the aspiration group, and 236 in the craniotomy group) received treatment and were included in the intention-to-treat analysis. Primary efficacy analysis revealed that 73 of 219 (33.3%) in the endoscopy group, 72 of 220 (32.7%) in the aspiration group, and 47 of 212 (22.2%) in the craniotomy group achieved favorable functional outcome at the 6-month follow-up (P = .017). We got similar results in subgroup analysis of deep hemorrhages, while in lobar hemorrhages the prognostic outcome was similar among three groups. Old age, deep hematoma location, large hematoma volume, low preoperative GCS score, craniotomy, and intracranial infection were associated with greater odds of unfavorable outcomes. The mean hospitalization expenses were ¥92,420 in the endoscopy group, ¥77,351 in the aspiration group, and ¥100,947 in the craniotomy group (P = .000). CONCLUSIONS: Compared with small bone flap craniotomy, endoscopic surgery and stereotactic aspiration improved the long-term outcome of hypertensive ICH, especially deep hemorrhages. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02811614.

Natural Underwater Bioadhesive Offering Cohesion Modulation via Hydrogen Bond Disruptor: A Highly Injectable and in Vivo Stable Remedy for Gastric Ulcer Resolution.

Injectable bioadhesives are attractive for managing gastric ulcers through minimally invasive procedures. However, the formidable challenge is to develop bioadhesives that exhibit high injectability, rapidly adhere to lesion tissues with fast gelation, provide reliable protection in the harsh gastric environment, and simultaneously ensure stringent standards of biocompatibility. Here, a natural bioadhesive with tunable cohesion is developed based on the facile and controllable gelation between silk fibroin and tannic acid. By incorporating a hydrogen bond disruptor (urea or guanidine hydrochloride), the inherent network within the bioadhesive is disturbed, inducing a transition to a fluidic state for smooth injection (injection force <5 N). Upon injection, the fluidic bioadhesive thoroughly wets tissues, while the rapid diffusion of the disruptor triggers instantaneous in situ gelation. This orchestrated process fosters the formed bioadhesive with durable wet tissue affinity and mechanical properties that harmonize with gastric tissues, thereby bestowing long-lasting protection for ulcer healing, as evidenced through in vitro and in vivo verification. Moreover, it can be conveniently stored (≥3 m) postdehydration. This work presents a promising strategy for designing highly injectable bioadhesives utilizing natural feedstocks, avoiding any safety risks associated with synthetic materials or nonphysiological gelation conditions, and offering the potential for minimally invasive application.

Integrated Sensors for Soft Medical Robotics.

Minimally invasive procedures assisted by soft robots for surgery, diagnostics, and drug delivery have unprecedented benefits over traditional solutions from both patient and surgeon perspectives. However, the translation of such technology into commercialization remains challenging. The lack of perception abilities is one of the obstructive factors paramount for a safe, accurate and efficient robot-assisted intervention. Integrating different types of miniature sensors onto robotic end-effectors is a promising trend to compensate for the perceptual deficiencies in soft robots. For example, haptic feedback with force sensors helps surgeons to control the interaction force at the tool-tissue interface, impedance sensing of tissue electrical properties can be used for tumor detection. The last decade has witnessed significant progress in the development of multimodal sensors built on the advancement in engineering, material science and scalable micromachining technologies. This review article provides a snapshot on common types of integrated sensors for soft medical robots. It covers various sensing mechanisms, examples for practical and clinical applications, standard manufacturing processes, as well as insights on emerging engineering routes for the fabrication of novel and high-performing sensing devices.