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INTRODUCTION: Spinal extradural arachnoid cyst (SEAC) is a rare condition that can cause significant neurological symptoms. Accurate diagnosis and effective surgical treatment are crucial for patient recovery. This study aims to elucidate the diagnostic process and surgical treatment strategies for SEAC through a case report. CASE PRESENTATION: A 33-year-old female patient with no significant medical history presented with intermittent lower back pain for over three months, which gradually worsened, but without accompanying limb numbness or weakness. Neurological examination revealed no abnormalities. Magnetic resonance imaging (MRI) and myelography confirmed a spinal extradural arachnoid cyst at the thoracic level. The patient underwent minimally invasive surgical resection of the cyst and dural repair, resulting in significant relief of pain postoperatively. DISCUSSION: This case highlights the importance of precise diagnostic localization and meticulous surgical technique in treating SEAC. The patient showed significant improvement in symptoms post-surgery, with no recurrence observed during follow-up. CONCLUSION: The successful treatment of SEAC in this case demonstrates the effectiveness of minimally invasive surgical resection and dural repair. This case provides valuable insights and recommendations for managing similar cases in clinical practice.
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Deep resource extraction has been affected by the complex geological environment of "three highs and one disturbance" for a long time. The surrounding rocks experience strong unloading stress disturbance during the underground resource extraction. The creep characteristics of the perimeter rocks are of great theoretical and practical value. Firstly, the triaxial pre-peak loading and unloading tests on the prepared samples are conducted on the intact rock samples using the TAW-200 rock mechanics test system. Then the rock samples with different degrees of pre-peak unloading damage were prepared under the condition of pre-peak yield. Finally, the uniaxial creep tests were carried out to study the uniaxial creep mechanical properties. The results show that the wave velocities of the damaged rock samples are reduced to different degrees compared with those of the intact rock samples, the creep of the pre-peak unloading damaged rock has a time-dependent damage effect, and the study results are similar to those of the conventional uniaxial creep test of the white sandstone. The instantaneous strain at all stress levels of the damaged rock samples increased gradually with the stress level, which is consistent with the non-linear functional relationship; Based on the time-dependent damage effect, the two-parameter Weibull distribution function was introduced into the West Plains viscoelasticity model, and a creep damage model for white sandstone was proposed. The improved Nishihara model can simulate the uniaxial creep characteristics of each damaged rock sample at various stress levels.
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Fibrous carbon nanotubes (CNTs) and lamellar graphene oxide (GO) exhibit significant advantages for improving the fatigue properties of rubber composites. In this work, the synergistic effect of CNTs and GO on the modification of the microstructure and fatigue properties of natural rubber (NR) was comprehensively investigated. Results showed that CNTs and GO were interspersed, and they formed a strong filler network in the NR matrix. Compared with those of CNT/NR and GO/NR composites, the CNT-GO/NR composites showed the smallest crack precursor sizes, the lowest crack growth rates, more branching and deflections, and the longest fatigue life.