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Background: Pneumocephalus is a rare complication after an elective lumbar spine surgery. Full endoscopic lumbar diskectomy (FELD) is an evolving minimally invasive surgical procedure gaining its popularity in the past decade. Although seizure was recognized as a possible complication, organic injury to the central nervous system such as pneumocephalus has not yet been reported after FELD., Case Description: A 63-year-old man with L3-4 intervertebral disk herniation received FELD via the transforaminal approach under general anesthesia. A small dural tear about 2 mm was encountered. After the operation, the patient was unable to recover from anesthesia and failed to be extubated due to tachypnea and generalized tonic-clonic seizures. Emergent brain computed tomography (CT) revealed pneumocephalus in the subdural and subarachnoid space. Pure oxygen was given, and hyperbaric oxygen therapy (HBO 2 ) was arranged immediately. Fortunately, he started to regain his consciousness 8 hours after the operation and had full recovery of consciousness on the next day. Follow-up brain CT showed nearly complete resolution of the pneumocephalus. He had no neurologic deficits at final follow-up., Conclusions: This case report highlights the risk of pneumocephalus with conscious disturbance when a dural tear occurs during FELD under general anesthesia. FELD is safer when performed under local anesthesia because the patient is awake to report his discomfort and thus possible to prevent serious neurologic sequels. An emergent brain CT is critical to obtain a prompt diagnosis and HBO 2 is probably helpful for resolving the mass effect caused by the pneumocephalus., (Copyright © 2019 Elsevier Inc. All rights reserved.)

This research studies the morphology and characterization of three-dimensional (3D) micro-porous structures produced from biodegradable chitosan for use as scaffolds for cells culture. The chitosan 3D micro-porous structures were produced by a simple liquid hardening method, which includes the processes of foaming by mechanical stirring without any chemical foaming agent added, and hardening by NaOH cross linking. The pore size and porosity were controlled with mechanical stirring strength. This study includes the morphology of chitosan scaffolds, the characterization of mechanical properties, water absorption properties and in vitro enzymatic degradation of the 3D micro-porous structures. The results show that chitosan 3D micro-porous structures were successfully produced. Better formation samples were obtained when chitosan concentration is at 1-3%, and concentration of NaOH is at 5%. Faster stirring rate would produce samples of smaller pore diameter, but when rotation speed reaches 4000 rpm and higher the changes in pore size is minimal. Water absorption would reduce along with the decrease of chitosan scaffolds' pore diameter. From stress-strain analysis, chitosan scaffolds' mechanical properties are improved when it has smaller pore diameter. From in vitro enzymatic degradation results, it shows that the disintegration rate of chitosan scaffolds would increase along with the processing time increase, but approaching equilibrium when the disintegration rate reaches about 20%.

In this study, gelatin blended with arabic gum microcapsules containing camphor oil with added polystyrene were fabricated by a compound coacervation method. The parameters of oil/wall volume ratio, emulsification stirring speed, concentration of cross-linking agent, treated time and oil release properties were investigated. In order to improve the constant release effect of camphor oil, oil-soluble polystyrene (PS) was used as a sustained release agent. The camphor oil release curves were expressed by the exponential equation: psi(t)=C(eq)(1-e(-t/tau)), where psi(t) represent the variant of camphor oil concentration in the operation environment, C(eq) as the equilibrium state, t as the release time and tau as time constant. C(eq) and tau are significant factors pertaining to the camphor oil release properties. The results indicated that, for the microcapsules, the optimal oil/wall volume ratio was 0.75 to achieve the encapsulation efficiency of 99.6 wt.%. The average particle size were 294.7+/-14.2 microm, 167.2+/-11.2 microm, 85.7+/-8.7 microm at the homogenization stirring speed of 500, 1000, and 2000 rpm, respectively. The effect of sustained oil release will increase whereas the stirring speed decreases and the concentration of glutaraldehyde (GA) and treated time increases. Along with the increasing of quantity of polystyrene added, C(eq) decreased and tau increased, indicating that the sustained oil release amount and the release rate depend on the quantity of PS considerably.