Suchergebnisse

In this work, vanadium pentoxide (V2O5) thin films were prepared using rf magnetron sputtering on silicon wafer and glass substrates from V2O5 target at 200 °C substrate temperature, followed by annealing at 400 and 500 °C in air for 2 h. The prepared thin films were examined by X-ray diffraction (XRD), forier transform infra-red spectroscopy (FTIR), UV-visible absorbance, and direct current coductivity to study the effects of annealing temperature on their structural and optical properties. The XRD analysis exhibited that the annealing promoted the highly crystallized V2O5 phase that is highly orientated along the c direction. The crystalline size increased from 22.5 nm to 35.4 nm with increasing the annealing temperature to 500 °C. The FTIR spectroscopy showed the enhancement of the characteristics band for the V2O5 with increasing annealing temperature to 500 °C. The optical study showed that the energy gap for the sample deposited on glass slides decreased from 2.85 eV, for as deposited sample, to 2.6 eV upon annealing the sample to 500 °C. There was a linear dependence between sensitivity and relative humidity (RH) at the range from 25% to 70%, while the behavior was exponential at high RH range.

Abstract
Background Transpedicular screw (TPS) misplacement is still a nightmare for spine surgeons. Preoperative planning is one of the methods that a surgeon could use to minimize this complication. This study aims to compare the efficacy of three-dimensional (3D) and two-dimensional (2D) preoperative planning in posterior lumbar TPSs placement performed using the freehand technique.
Patients and Methods Patients who underwent posterior TPSs placement for degenerative lumbar spondylolisthesis or spinal stenosis using the freehand technique between November 2021 and October 2022 were evaluated retrospectively. In total, 33 and 30 patients who met the inclusion criteria were consecutively operated on with preoperative 2D and 3D planning, respectively. The patients were divided into the 2D preoperative planning group (2DG) and 3D preoperative planning group (3DG) and the two groups were compared.
Results Sixty-three patients were operated during the study period. There was no significant difference between the groups regarding blood transfusion, operation time, and radiation exposure. Although the accuracy of TPSs positioning was 94.2 and 96.5% in the 2DG and 3DG, respectively, the difference between the groups was not statistically significant. The upper facet joint violation rate was 12.8% (n = 20) in the 2DG versus 3.5% (n = 5) in the 3DG (p = 0.006). All L4 TPSs were inserted with their standard entry points without any modification (p < 0.0001; relative/risk ratio = 0.64). The modification rate was higher in L1, L2, and L5 TPSs (p < 0.0001; χ
2 = 24.7).
Conclusion For patients with degenerative lumbar diseases, 3D preoperative planning in posterior lumbar instrumentation surgeries performed with the freehand technique decreased the upper facet joint violation rate.

Abstract
Background and Study Aims Chiari malformation type 1 (CM1) is one of the most discussed neurosurgical disorders. No consensus exists how to manage adult CM1 patients. We aimed to evaluate all adult CM1 patients consecutively managed at our institutions and discuss our approach based on the phase-contrast (PC) magnetic resonance imaging (MRI).
Patients and Methods The medical charts of adult patients diagnosed with CM1 at two referral neurosurgical centers between 2010 and 2017 were reviewed. The patients were either managed conservatively or surgically. We evaluated the patients clinically with the Chicago Chiari Outcome Scale (CCOS). The radiologic diagnosis was based on both craniocervical and PC-MRI.
Results Ninety adult CM1 patients were managed conservatively. Conservative treatment failed in 5 of these 90 patients. Seventy-two patients (including those 5 patients who did not benefit from conservative treatment) underwent posterior fossa decompression with duraplasty. Eighty-five patients (94.4%) from the conservative group and 61 patients (84.7%) from the surgical group were treated successfully. An aqueductal stroke volume (ASV) value of 12 µL was found as the cutoff value for surgical candidates. A strong positive correlation between the increase in ASV values and clinical improvement was observed.
Conclusions PC-MRI can help in the management and follow-up of adult CM1 patients. Conservative management is possible in selected symptomatic CM1 patients with a high ASV (ASV > 15 µL). Surgery should be considered in patients with an ASV ≤ 12 µL. CM1 patients with ASV ≤12 to >15 μL require close follow-up. Long-standing symptoms, severe sleep apnea, symptoms influencing functionality, and syrinx are factors that affected outcomes negatively.

Abstract
Background and Study Aims Spinal subdural abscesses (SSAs) are rare and have a poor prognosis, especially when they are diagnosed late. In the literature, most cases of SSAs have been reported as case reports and small case series. In this study, we aimed to evaluate the surgical outcomes of four consecutive SSA patients.
Material and Methods In this retrospective study, we reviewed the medical charts of four SSA patients who underwent surgical intervention at two neurosurgical centers from September 2012 to September 2019.
Results Our series comprised four patients (three females and one male) with SSA (intradural–extramedullary) who were treated surgically. Holocord SSA was observed in two patients. The mean age was 15.1 ± 17.1 years. Unsteady gait and weakness of legs was the presenting symptom in all patients. The mean preoperative course was 5.3 ± 3.4 weeks. The causative pathogens were methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Mycobacterium tuberculosis. In the fourth case, the pathogen was non–M. tuberculosis. In the 44th postoperative month, the patient underwent surgery for an intramedullary abscess. The causative pathogen was E. coli. Except for one adolescent male who was paraplegic at presentation, improvement was observed in all patients at their last follow-up after 54.0 ± 35.9 months after surgery.
Conclusion Early diagnosis and urgent surgical intervention are essential for a good prognosis in SSA cases. We recommend drainage followed by appropriate antibiotics.

Abstract
Background Surgical site infection (SSI) is one of the most severe complications of spinal fusion surgery that lead to increased morbidity and mortality rates. Prophylactic antibiotic usage is one of the methods that reduce the possibility of SSI in this procedure. The aim of this study was to determine the effect of local subfascial teicoplanin usage on radiologic and functional outcomes and compare it to the effect of vancomycin on surgical outcomes in patients who underwent decompression with posterior instrumentation (DPI) for lumbar spinal stenosis (LSS).
Methods Medical charts of patients with LSS who received DPI and met the study criteria were divided into three groups: the teicoplanin group included patients who underwent DPI with local teicoplanin before closure, the vancomycin group included patients who underwent DPI with local vancomycin, and the control group included patients who underwent DPI without any local prophylactic antibiotics.
Results A total of 101 patients were included in the study. No significant differences were found among groups regarding demographics, follow-up, and clinical and functional outcomes. No significant differences were observed among groups regarding postoperative improvements in SF-36-MCS, SF-36-PCS, Oswestry Disability Index, and Visual Analog Scale (VAS; p > 0.05). In the teicoplanin and vancomycin groups, the SSI rate was lower than that in the control group (2/35, 1/34, and 5/32, respectively, p = 0.136) without statistical significance; however, the postoperative fusion volume was significantly higher in the teicoplanin group when compared to the other groups (3.35 ± 1.08, 2.68 ± 1.17, and 2.65 ± 1.28 cm3, respectively, p = 0.007).
Conclusions Although its cost is relatively higher, teicoplanin was a good alternative to vancomycin in preventing SSIs with a higher fusion rate, but no superiority was observed regarding other outcomes.

Abstract
Background One of the antioxidant mechanisms is the dynamic balance between thiol and disulfide, which, in subarachnoid hemorrhage and other chronic diseases, is disrupted in favor of the latter. The two most commonly used oxidative stress (OS) biochemical markers are the oxidative stress index (OSI) value, which indicates the total oxidant status (TOS) and total antioxidant status (TAS) balance, and the thiol–disulfide (TDS) value, which indicates the total thiol (TT) and native thiol (NT) balance. High OS levels require further investigations. We aimed to investigate the OS level in aneurysmal SAH (aSAH) patients.
methods In this clinical prospective study, blood samples were collected from 50 consecutively treated patients with aSAH and 50 volunteers. Serum TOS, TAS, TT, and NT levels were measured using Erel's method via a spectrophotometer. The Glasgow Coma Scale (GCS) scores, Fisher grades, length of hospital stay (LOS), and the Glasgow Outcome Scale (GOS) scores were recorded. Consequently, the OSI and TDS values were calculated in all participants.
Results A statistically significant difference was observed in the TAS, TOS, OSI, and TDS values between the aSAH patients and the controls. The TT and NT values were significantly lower in aSAH patients than in the controls. A correlation was identified between the OSI values and the GCS scores. Although a correlation was observed between the TDS values and the LOS, no correlation was found between the OSI and the TDS values.
Conclusion The OSI and TDS, which are OS indicators, might serve as the additional objective nominal data to evaluate the treatment efficacy and follow-up for SAH patients. Moreover, decreasing the OSI values and increasing the TT values can be used as improvement indicators in the treated aSAH patients. If we can reduce the OS at the early stage of SAH, it could improve the prognosis by reducing both the morbidity and mortality rates. Further randomized investigations are required to prove the findings in this prospective study.

Abstract
Background and Study Aims Spinal cord injury (SCI) is one of the most complicated pathologies that affect active young males. miR-21 primarily regulates several cellular processes. We aimed to elucidate the regulatory role of miR-21 and test methylprednisolone as a disease-modifying agent on experimental SCI tissues.
Methods A total of 36 8- to 10-week-old adult female Sprague-Dawley rats weighing 250 to 300 g were used. Animals were randomly divided into six groups. Except for groups 1 and 4, the spinal trauma model was applied to all animal groups using the clipping method. In groups 3 and 6, methylprednisolone was given. For real-time polymerase chain reaction (PCR) investigations, rats in groups 1, 2, and 3 were reoperated on after the first postoperative day, whereas those in groups 4, 5, and 6 were reoperated on after postoperative day 7 and spinal cord samples from the laminectomy area were removed for gene expression analysis. Relative gene expression of miR-21, Gfap, Vim, Stat3, Faslg, Pten, Bax, Bcl2, Cox2, and Il6 were determined with quantitative reverse transcription (qRT) PCR.
Results In group 3, the miR-21 expression significantly increased compared with groups 1 and 2. When compared with group 3, a decrease in miR-21 expression was observed in group 6 (p < 0.05). When compared with group 4, group 6 had lower levels of Gfap, Pten, Stat3, and Bax (p < 0.05).
Conclusions miR-21 supports the beneficial aspects of the body's healing mechanisms following SCI. In the acute phase, the use of methylprednisolone increases miR-21 expression in the early period of trauma. Methylprednisolone increases some astrogliosis and inflammation biomarkers' levels; however, it did not affect the apoptotic biomarkers.