Axial reciprocation of rotating impeller: a new concept of antithrombogenecity in centrifugal pump

For long-term application, rotary pumps have to solve the problems of bearing wear and thrombosis along the bearing. Most investigators choose the magnetic bearing to realize zerofriction and no contact between the rotor and stator; the former avoids the mechanical wear and the latter eliminates the possibility of thrombus formation. The authors have tried and found, however, that it is difficult to apply a magnetic bearing to the rotary pump without disturbing its simplicity, reliability and implantability, and have therefore developed a much simpler and much more creative approach to achieve the same results. Instead of using a sliding bearing, a rolling bearing has been devised for the pump, and its friction is about 1/15 of the sliding bearing. Furthermore, a wear-proof material of ultra-high-molecular weight polythene has been adopted to make the rollers, and its anti-wear property is 8 times better than metal. Thereby, the service life of the bearing has been prolonged to ten years according to the documents provided by the producer. In order to prevent the thrombus formation along the bearing, the impeller reciprocates axially as the impeller changes its rotating speed periodically to produce a pulsatile flow. The reciprocation is the result of the effects of a magnetic force between the motor rotor and stator, and a hydraulic force between the blood flow and the impeller. Similar to a piston pump, the oscillating impeller can make the blood flow in and out of the bearing, resulting in wash-out once a circle. This obviously helps to prevent thrombosis along the bearing and in the pump. The endurance tests with saline of this novel pump demonstrated the durability of the device. It promises to be able to assist the circulation of patients permanently, and to be able to replace heart transplantation in the future.     

Three-dimensional virtual planning in mandibular advancement surgery: Soft tissue prediction based on deep learning

The study aimed at developing a deep-learning (DL)-based algorithm to predict the virtual soft tissue profile after mandibular advancement surgery, and to compare its accuracy with the mass tensor model (MTM).Subjects who underwent mandibular advancement surgery were enrolled and divided into a training group and a test group. The DL model was trained using 3D photographs and CBCT data based on surgically achieved mandibular displacements (training group). Soft tissue simulations generated by DL and MTM based on the actual surgical jaw movements (test group) were compared with soft-tissue profiles on postoperative 3D photographs using distance mapping in terms of mean absolute error in the lower face, lower lip, and chin regions.133 subjects were included — 119 in the training group and 14 in the test group. The mean absolute error for DL-based simulations of the lower face region was 1.0 ± 0.6 mm and was significantly lower (p = 0.02) compared with MTM-based simulations (1.5 ± 0.5 mm).ConclusionThe DL-based algorithm can predict 3D soft tissue profiles following mandibular advancement surgery. With a clinically acceptable mean absolute error. Therefore, it seems to be a relevant option for soft tissue prediction in orthognathic surgery. Therefore, it seems to be a relevant options.     

人工智能时代的正颌外科发展

简要回顾人工智能（AI）技术的概念及其在不同时代发展历程,概述AI在医疗领域的应用,回顾综述AI在正颌外科发展的研究进展、存在的问题及可能的发展方向,指出AI在正颌外科的发展充满机遇与挑战并存。     

Artificial Organs 2014: A Year in Review

In this Editor's Review, articles published in 2014 are organized by category and briefly summarized. We aim to provide a brief reflection of the currently available worldwide knowledge that is intended to advance and better human life while providing insight for continued application of technologies and methods of organ Replacement, Recovery, and Regeneration. As the official journal of the International Federation for Artificial Organs, the International Faculty for Artificial Organs, the International Society for Rotary Blood Pumps, the International Society for Pediatric Mechanical Cardiopulmonary Support, and the Vienna International Workshop on Functional Electrical Stimulation, Artificial Organs continues in the original mission of its founders “to foster communications in the field of artificial organs on an international level.” Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide meaningful suggestions to the author's work whether eventually accepted or rejected. Without these excellent and dedicated reviewers, the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, John Wiley & Sons, for their expert attention and support in the production and marketing of Artificial Organs. We look forward to reporting further advances in the coming years.     

Mechanical ventilation in critically-ill pregnant women: a case series

BackgroundApproximately 0.1–0.2% of pregnancies are complicated by respiratory failure requiring mechanical ventilatory support, but few data exist to inform clinical management. This study aimed to characterize current practice and the effect of delivery on respiratory function.MethodsA retrospective review was performed of pregnant women who received mechanical ventilation for more than 24 h, from four intensive care units in institutions with large-volume obstetric units.ResultsData were collected from 29 patients with a mean gestation at intensive care unit admission of 25.3 ± 6 weeks. Tidal volumes were 7.7 ± 1.7 mL/kg predicted body weight. Estimated respiratory system compliance was reduced, but was higher in four patients ventilated for neurological conditions without lung disease. Three maternal and three neonatal deaths occurred. Ten patients delivered while on ventilatory support: one spontaneous delivery, four for obstetric indications and five for worsening maternal condition. Following delivery of these 10 patients, three demonstrated a greater than 50% decrease in oxygenation index and five a greater than 50% increase in compliance. No characteristics identified which patients may benefit from delivery.ConclusionsReview of current practice in four centers suggests that mechanical ventilation in pregnant patients follows usual guidelines applicable to non-pregnant patients. Delivery was associated with modest improvement in maternal respiratory function in some patients. Any potential benefit of delivery in improving maternal physiology must be weighed against the stress of delivery. The risks of premature birth for the fetus must be weighed against continued exposure to maternal hypoxemia and hypotension.     

Artificial disc and vertebra system: a novel motion preservation device for cervical spinal disease after vertebral corpectomy

OBJECTIVE:To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group.METHODS:Biomechanical tests were conducted on 18 human cadaveric cervical specimens. The range of motion and the stability index range of motion were measured to study the function and stability of the artificial disc and vertebra system of the intact group compared with the fusion group.RESULTS:In all cases, the artificial disc and vertebra system maintained intervertebral motion and reestablished vertebral height at the operative level. After its implantation, there was no significant difference in the range of motion (ROM) of C3–7 in all directions in the non-fusion group compared with the intact group (p>0.05), but significant differences were detected in flexion, extension and axial rotation compared with the fusion group (p<0.05). The ROM of adjacent segments (C₃₋₄, C₆₋₇) of the non-fusion group decreased significantly in some directions compared with the fusion group (p<0.05). Significant differences in the C_4-6 ROM in some directions were detected between the non-fusion group and the intact group. In the fusion group, the C₄₋₆ ROM in all directions decreased significantly compared with the intact and non-fusion groups (p<0.01). The stability index ROM (SI-ROM) of some directions was negative in the non-fusion group, and a significant difference in SI-ROM was only found in the C₄₋₆ segment of the non-fusion group compared with the fusion group.CONCLUSION:An artificial disc and vertebra system could restore vertebral height and preserve the dynamic function of the surgical area and could theoretically reduce the risk of adjacent segment degeneration compared with the anterior fusion procedure. However, our results should be considered with caution because of the low power of the study. The use of a larger sample should be considered in future studies.     

Potential applications of artificial intelligence in colorectal polyps and cancer: Recent advances and prospects

Since the advent of artificial intelligence(AI) technology, it has been constantly studied and has achieved rapid development. The AI assistant system is expected to improve the quality of automatic polyp detection and classification. It could also help prevent endoscopists from missing polyps and make an accurate optical diagnosis. These functions provided by AI could result in a higher adenoma detection rate and decrease the cost of polypectomy for hyperplastic polyps. In addition, AI has good performance in the staging, diagnosis, and segmentation of colorectal cancer. This article provides an overview of recent research focusing on the application of AI in colorectal polyps and cancer and highlights the advances achieved.