[Application of two kinds of electrophysiological monitoring techniques for the prediction of facial nerve outcomes after vestibular Schwannoma surgery].

Objective: To investigate the application of transcranial facial nerve motor evoked potential (FNMEP) and direct nerve electrical stimulation (DNES) for the prediction of facial nerve function after vestibular schwannoma surgery. Methods: The clinical data of 106 patients who underwent vestibular schwannoma surgery under electrophysiological monitoring of facial nerve between 2017 and 2021 were retrospectively examined, and there were 57 males and 49 females, with a mean age of (51±11) years. Neuroelectrophysiological monitoring was performed in all patients during the operation. After the tumor was removed, FNMEP and DNES were used for electrophysiological evaluation of facial nerve function. The amplitude ratios of FNMEP to baseline (M1) and the brainstem segment to the internal auditory canal segment of DNES (M2) were recorded after the tumor was removed, respectively. The correlation between these two ratios and facial nerve function at 1 day, 1 month and 3 months after the operation were compared. According to the House-Brackmann (HB) scale, Grade Ⅰ-Ⅱ refers to good facial nerve function, and grade Ⅲ-Ⅵ refers to moderate and severe facial nerve dysfunction. Non-parameter Spearman correlation coefficient was used to evaluate the correlation between M1 and M2 and facial nerve function at 1 day, 1 month and 3 months after operation, and the receiver operating characteristic (ROC) curves were plotted to verify the diagnostic efficacy of M1 and M2 for predicting the prognosis of postoperative facial nerve function. Results: Among 106 patients, 102 cases (96.3%) underwent total tumor resection, 4 patients (3.7%) underwent subtotal resection, 104 patients (98.1%) had anatomical preservation of facial nerves, and there were no deaths reported. All patients could evoke reliable FNMEP and 2 patients could not evoke DNES in the brainstem segment of the facial nerve. There were 81 (76.4%), 99 (93.4%) and 103 patients (97.2%) with satisfactory function of facial nerve at 1 day, 1 month and 3 months after surgery, respectively. M1 had large absolute values of Spearman correlation coefficient at 1 day (ρ=|-0.648|) and 1 month (ρ=|-0.552|) after surgery (both P<0.001), while M2 showed a greater absolute value of Spearman correlation coefficient at 3 months (ρ=|-0.395|) than that of M1 (ρ=|-0.378|) (P<0.001). Cut-off value of M1 was 0.58 (sensitivity=0.92, specificity=0.64), and that of M2 was 0.36 (sensitivity=0.64, specificity=1.00). Meanwhile, M1<0.58 or M2<0.36 suggested moderate and severe impairment of facial nerve function. Conclusions: Both FNMEP and DNES during vestibular schwannoma surgery can effectively evaluate the postoperative facial nerve function. FNMEP is better than DNES in predicting the early postoperative facial nerve function, but DNES is better for predicting the long-term postoperative facial nerve function.

Thermoelectric signals of state transition in polycrystalline SmB6.

Topological Kondo insulator SmB6 has attracted quite a lot of attention from the condensed matter physics community. A number of unique electronic properties, including low-temperature resistivity anomaly, 1D electronic transport and 2D Fermi surfaces have been observed in SmB6. Here, we report on thermoelectric transport properties of polycrystalline SmB6 over a broad temperature from 300 to 2 K. An anomalous transition in the temperature-dependent Seebeck coefficient S from S(T) [Formula: see text] T (-1) to S(T) [Formula: see text] T was observed around 12 K. Such a transition demonstrates a transition of conductivity from 3D metallic bulk states to 2D metallic surface states with insulating bulk states. Our results suggest that the thermotransport measurements could be used for the characterization of state transition in topological insulators.

[Effects of oral interventions on carotid artery, serum C-reactive protein and interleukin 6 in chronic periodontitis rats with atherosclerosis].

Objective: To explore the effect of variousoral interventions on the development of atherosclerosis in SD rats with chronic periodontitis and atherosclerosis. Methods: Forty-four male SD rats were randomly divided into three groups, Group A(healthycontrol), Group B(atherosclerosis, As) and Group C(chronic periodontitis with atherosclerosis, CP+As). Rats in Group C were further divided randomly into Subgroup C1(natural process, n=7), Subgroup C2(mechanical therapy, n=7), Subgroup C3(systemic antibiotic treatment, n=7) and Subgroup C4(tooth extraction, n=7). Rats in each subgroup of Group C received one of the appropriate oral interventions. The pathological lesions of carotid artery plaque were stained with hematoxylin and eosin(HE) and observed under a light microscope. The serum levels of C-reactive protein(CRP) and interleukin-6(IL-6) were detected by enzyme-linked immunosorbent assay (ELISA) in five different time points. Results: Pathological results showed that increased foam cells and inflammatory cells were found in Group B. Irregular vessel wall, inflammatory cell, the foam cells, disordered elastic fibers were observed in Group C. While fewer in flammatory cells were found in Subgroup C2 than that in other subgroups. The changing trends of the serum levels of CRP and IL-6 were consistant with time went by. The levels of serum CRP, IL-6 in Groups B and C were significantly higher than that in Group A at all time points(P<0.01). The levels of serum CRP, IL-6 in Subgroup C1 became higher gradually(P<0.05) with time being. The serum levels after oral interventions changed significantly compared with the baseline levels(P<0.05). One week after the second round of intervention, the serum levels of CRP(C2: [9.43 ± 1.28] µg/L, C3: [12.38±0.81] µg/L, C4: [15.76±1.03] µg/L) and IL-6 (C2: [94.71±16.09] µg/L, C3: [112.89± 40.16] µg/L, C4: [175.11 ± 50.79] µg/L) in intervention subgroups reached the peaksand were significantly higher than that of Group B(CRP: [6.96±1.30] µg/L, IL-6: [43.36±7.46] µg/L) and Subgroup C1(CRP: [8.41± 0.46] µg/L, IL-6: [73.59±27.89] µg/L)(P<0.05). The changes of serum levels then declined with time beingin each group/subgroupand level in Subgroup C2 was the lowest(P<0.01). Conclusions: In chronic periodontitis of rats with atherosclerosis, permanent periodontitis mightsignificantly raise the risk of the development of atherosclerosis. Oral interventions increased the risk of atherosclerosis in a short period of time because of increased levels of serum inflammatory factors, but effective improvement could be observed on the As lesions after oral interventions in along term, especially after the periodontal mechanical therapy.

Middle-period curative effect of posterior lumbar intervertebral fusion (PLIF) and interspinous dynamic fixation (Wallis) for treatment of L45 degenerative disease and its influence on adjacent segment degeneration.

OBJECTIVE: To study middle period curative effect of posterior lumbar intervertebral fusion (PLIF) and interspinous dynamic fixation (Wallis) in the treatment of L45 degenerative disease and its influence on adjacent segment degeneration. PATIENTS AND METHODS: 66 patients with lumbar L45 degenerative diseases were selected for study. The patients were randomly divided into PLIF operation group and Wallis operation group with 33 cases in each group. The patients were analyzed for T1ρ value, functional score and UCLA classification of L3/4 and L5/S1 segment in different periods of two groups of patients. RESULTS: The level of T1ρ for L3/4 and L5/S1 segment in two groups between preoperative period and last follow-up showed a decreasing trend, while level of T1ρ value of L3/4 segment in PLIF operation group was significantly lower than Wallis group. Within group comparison, the level of T1ρ for L3/4 segment in PLIF operation group until the last follow-up was significantly lower than that before operation. While comparing two groups, ODI scores after operation for PLIF group and Wallis group was significantly lower than those before operation and JOA score was significantly higher than that before operation. The UCLA grade of L3/4 and L5/S1 segment of the two groups was significantly improved compared with that at the time of the last follow-up. CONCLUSIONS: Both PLIF and Wallis methods are effective for the treatment of lumbar degenerative disease of L45. Wallis operation has slight advantage in slowing down the speed of intervertebral disc degeneration in the upper adjacent segment of the patient.

Resection of meningiomas with implantable microwave coagulation.

Implantable microwave coagulation was used to perform resection on 62 patients that had intracranial meningiomas. When 20-60 W microwave power was applied for 15 s, the temperature at the center of the tumor tissue was 43-63 degrees C; 30 mm from the center, the temperature was under 40 degrees C. Histological changes in the center of the tumor showed coagulative necrosis, diminished nuclei, and obliterated blood vessels. The changes at 10-20 mm from the center of the tumor showed coagulative necrosis and degeneration and, 30-50 mm from the center of the tumor, showed normal cell morphology after microwave coagulation. The thermal field in brain tumor has an effective diameter of about 40 mm. No side effects on the normal brain tissues were observed. The amount of blood loss during the operation was minimal while the meningioma was coagulated, especially when the meningioma was located at the skull base or in the parasagittal or cerebral convexity region. After microwave coagulation, the entire tumor could easily be removed. Among the 62 surgically treated cases, gross total tumor excision was 85 percent. No postoperative complications occurred after microwave coagulation, and there was no operative mortality in the series. We believe that this new technique has the advantage of simplicity, less blood loss, and smooth postoperative procedures. Hemostatic effects during the operation are satisfactory, and blood transfusion can be reduced by 50-60 percent.