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Continuous intra-operative neurophysiological monitoring (CINM) that provides precise mapping of neural anatomy through the entire microsurgery process is essential to preserve the structural and functional integrity of the nerve. However, bulky and rigid electrodes used currently in clinics are usually unable to reliably maintain continuous and stable contacts with the vulnerable and complex nerve networks, thus often resulting in detrimental post-operative complications, such as hemiplegia and sensory disturbances. Here, we describe a biomechanically compatible, suture-free, and individually reconfigurable CINM based on soft and stretchable organic electronic materials. Due to both low impedance and modulus of our conducting polymer electrodes, we achievedfor the first timecontinuous recording of near-field action potential with high signal-to-noise ratio and minimal invasiveness during microsurgeries. Utilizing this unprecedented CINM modality, in conjunction with localized neurostimulation, we further demonstrated our approach in enabling optimal post-operative prognosis in preclinical animal models by preserving normal neural functions after a variety of tumor resection surgeries.

To investigate the expression characteristics, correlations with clinical factors, and prognostic values of phosphatase and tensin homolog (PTEN) and Ki-67 in cranial meningiomas.The expression of PTEN and Ki-67 at the mRNA level was analyzed in 34 frozen meningiomas. Clinical data collection, follow-up, correlations, and survival analyses were performed.Twenty-two men and 12 women were included in the study, with a median age of 52.72 ± 11.72 years on admission. The average expression levels of PTEN and Ki-67 were 2.71 ± 1.73 and 0.50 ± 0.57, respectively. The World Health Organization grade III meningiomas exhibited significantly lower levels of PTEN (P = 0.037), whereas grade I meningiomas expressed significantly lower levels of Ki-67 (P = 0.001). For recurrent lesions, the mean Ki-67 expression level was 0.97 ± 0.76, which was significantly greater than that of primary meningiomas with a mean value of 0.25 ± 0.13 (P0.001). The Ki-67 expression level was positively correlated with the tumor volume (P0.01) and negatively correlated with preoperative Karnofsky Performance Status scale (KPS, P0.01), postoperative KPS (P0.05), and follow-up KPS (P0.01). However, the PTEN expression level did not correlate with these variables. Based on the multivariate Cox analysis, Ki-67 expression level (P0.001, hazard ratio [HR] 8.16, 95% confidence interval [CI] 2.86-23.29), and PTEN expression level (P = 0.018, HR 0.47, 95% CI 0.25-0.88) were independent prognostic factors for tumor recurrence. Ki-67 (P = 0.001, HR 19.73, 95% CI 3.65-106.61) and PTEN expression levels (P = 0.024, HR 0.36, 95% CI 0.15-0.88) were also independent prognostic factors for mortality.A low PTEN expression and a high Ki-67 expression could predict malignancy in cranial meningiomas.

PURPOSE Evaluate the value of bilateral final/baseline threshold level changes of lower cranial nerve MEPs in postoperative swallowing function deterioration prediction. METHODS Bilateral lower cranial nerve motor-evoked potentials (MEPs) were recorded in 51 patients who underwent treatment for skull base and brainstem tumors. Corkscrew-like electrodes were positione 2 cm below C3/C4 and Cz. The MEPs were recorded from different muscle groups, including the posterior pharyngeal wall muscle, tongue muscle, genioglossus muscle, and cricothyroid muscle through paired needle electrodes. Swallowing function was assessed clinically using the Mann Assessment of Swallowing Ability score before and after the procedure at 7 days, 1 month, and 3 months. RESULTS Bilateral final/baseline threshold level increases in lower cranial nerve MEPs under the dual monitoring were significantly correlated with postoperative swallowing function deterioration (r = 0.660 at 7 days, r = 0.735 at 1 month, and r = 0.717 at 3 months; p < 0.05). Bilateral final/baseline threshold level changes of more than 20% were recorded in 23 of the 51 patients, with 21 patients experiencing swallowing function deterioration postoperatively. The other 28 patients had bilateral threshold level changes of less than 20%, with 26 patients maintaining or improving their swallowing function, and 12 of those patients presented transient deterioration of swallowing function in the early postoperative period. CONCLUSIONS Dual monitoring of lower cranial nerves and their different muscle groups MEPs was a safe and effective way to predict postoperative swallowing function. An increase in bilateral final/baseline threshold level change of more than 20% was predictive of permanent swallowing deterioration, especially in patients with poor swallowing function preoperatively.

We sought to clarify the expression characteristics and prognostic significance of transforming growth factor (TGF)-β3 in cranial meningiomas.We analyzed the expression of TGF-β3 at the mRNA level in 38 frozen meningioma samples. Clinical data collection, follow-up, correlations, and survival analyses were performed.World Health Organization (WHO) grade I meningiomas showed an average expression level of 2.55, which was higher than that of WHO grade II (average of 1.50) and WHO grade III (average of 0.21) (Kruskal-Wallis test, P = 0.008). For meningiomas with a history of surgery, the mean TGF-β3 expression level was 0.71, much lower than that of primary meningiomas with a mean value of 2.55 (Mann-Whitney U-test, P = 0.008). According to the Kaplan-Meier analysis and univariate Cox analysis, WHO grade (P = 0.001), history of surgery (P0.001), tumor volume (P = 0.045), preoperative Karnofsky Performance Status (P = 0.001), peritumoral brain edema (P = 0.039), postoperative radiotherapy (P = 0.001), degree of resection (P = 0.039), and TGF-β3 expression (P = 0.038) were prognostic factors for tumor recurrence. In addition, WHO grade (P0.001), history of surgery (P0.001), preoperative Karnofsky Performance Status (P = 0.002), peritumoral brain edema (P = 0.006), postoperative radiotherapy (P = 0.007), bone invasion (P = 0.03), and TGF-β3 expression (P = 0.041) were prognostic factors for mortality.TGF-β3 expression levels gradually declined with the increase of WHO grade and were lower in recurrent meningiomas than in primary meningiomas. Besides, low TGF-β3 expression was found to predict tumor recurrence and mortality in meningiomas based on univariate analysis.

The injection molding process of short fiber-reinforced polymer composites was investigated using smoothed particle hydrodynamics method. The polymer melt was modeled as a power law fluid, and the fibers were considered as rigid bodies. The flow behavior of short fiber-reinforced polymer composite melt and the motion and orientation of fibers were studied. The results showed that U-shaped fountain flow was generated at the flow front, and the center of the flow front gradually sank during the injection molding process; fibers were aligned to the flow direction in the cavity and near the wall in the sprue, and fibers accumulated at some points in the cavity. Additionally, the initial fiber configuration in the model influenced the final fiber orientation slightly. It was also found that the fiber orientation factor increased with the increase of fiber aspect ratio, and decreased with the increase of fiber content.