Decompressive craniectomy (DC) is a surgical method for managing highly elevated intracranial increased pressure (ICP) resulted from severe head trauma. This procedure is able to reduce the ICP rapidly and effectively. However, it may lead to kinds of secondary complications, which would cause patient's severe neurological dysfunction or even death. In this paper, we reviewed the literatures about surgical complications secondary to DC, and tried to bring up suggestions on surgical techniques aiming to prevention and treatment of these complications.

Objectives: In this case report, we describe the design, fabrication and clinical outcomes of a novel bioresorbable, mineralized collagen burr-hole plug for the reconstruction of craniotomy burr-holes.
Methods: Mineralized collagen burr-hole plugs were fabricated via a biomimetic mineralization process. The biomimetic mineralized collagen has a similar chemical composition and microstructure to natural bone tissue, thereby possessing good biocompatibility and osteoconductivity. The mineralized collagen burr-hole plugs were implanted into three patients, and clinical outcomes were evaluated at one-year follow-ups.
Results: All bone defects healed very well using the mineralized collagen burr-hole plugs, and there were no adverse reactions at the surgical sites.
Conclusions: The clinical outcomes indicated that the mineralized collagen was effective for reconstructing burr-holes in the skull after craniotomy.

Objective: The frontal lobe may be involved in circuits associated with depression, apathy, aggression, and other psychiatric symptoms. Although white matter changes (WMC) are related to the severity of behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer's disease (AD), it is unclear which part of the WMC may play the most important role in BPSD. This study was designed to investigate the relationship between the location of WMC and the severity of BPSD in AD patients. Methods: Among patients diagnosed with Alzheimer's disease between 2009 and 2014, 387 patients were retrospectively reviewed after those with pre-existing organic brain syndrome, psychiatric diseases, or toxic-metabolic encephalopathy were excluded. Patients' demographic and laboratory data, WMC measured with brain computed tomography and scored using the age-related white matter changes (ARWMC) scale, and neuropsychological tests, including the cognitive abilities screening instrument (CASI), the Mini-Mental State Examination (MMSE), the clinical dementia rating scale with sum-box (CDR-SB), and the neuropsychiatric inventory (NPI) were analyzed. Results: There was no significant difference in the NPI between patients with and without a history of stroke, hypertension, and diabetes. No significant difference in the NPI was identified between different sexes or different Apolipoprotein E (APOE) alleles. The NPI score was significantly correlated with the duration of education (r = -0.4515,P = 0.0172), CASI (r = -0.2915, P < 0.0001), MMSE (r = -0.8476, P < 0.0001), and CDR-SB (r = 2.2839, P < 0.0001). WMC in the right frontal lobe showed a significant difference in NPI in comparison to those without WMC (P = 0.0255). After adjusting for age, duration of education, and CASI, WMC in the right frontal lobe remained significantly associated with the NPI score (β = 3.8934,P = 0.042). Conclusions: WMC involving the right frontal lobe may play an important role in the BPSD in AD patients during their dementia diagnosis. Further studies are necessary to confirm whether controlling the risk factors of WMC can slow the progression of BPSD.

The reconstruction after peripheral nerve damage, especially for long-segment nerve defects, remains a clinical challenge. Autologous nerve graft transplantation is an efficient method for the repair of peripheral nerve defects, but the involved complications and shortcomings have greatly limited the clinical efficacy of treatments offered to patients with nerve defects. Thus, there is an urgent need to develop new therapeutic strategies and explore alternatives to autologous nerve transplantation in clinical practice, based on the knowledge of the peripheral nerve regeneration mechanism and biological histocompatibility principles. With significant advances in the research and application of nerve conduits, they have been used to repair peripheral nerve injury for several decades. In this paper, the study background of nerve conduits, their applications in clinic, status of conduit material research and construction of tissue-engineered artificial nerves were reviewed.

Objectives: Currently, the clinical repair of sciatic nerve injury remains difficult. Previous studies have confirmed that transplantation of adipose tissue-derived stem cells promotes nerve regeneration and restoration at peripheral nerve injury sites.
Methods: In this study, adipose tissue-derived stem cells were induced to differentiate into neural progenitor cells, transfected with a green fluorescent protein-containing lentivirus, and then transplanted into the lesions of rats with sciatic nerve compression injury.
Results: Fluorescence microscopy revealed that the transplanted cells survived, migrated, and differentiated in rats. At two weeks post-operation, a large number of transplanted cells had migrated to the injured lesions; at six weeks post-operation, transplanted cells were visible around the injured nerve and several cells were observed to express a Schwann cell marker. Sciatic function index and electrophysiological outcomes of the transplantation group were better than those of the control group. Cell transplantation promoted the recovery of motor nerve conduction velocity and compound muscle action potential amplitude, and reduced gastrocnemius muscle atrophy.
Conclusions: Our experimental findings indicate that neural progenitor cells, differentiated from adipose tissue-derived stem cells, are potential seed stem cells that can be transplanted into lesions to treat sciatic nerve injury. This provides a theoretical basis for their use in clinical applications.

Objectives: To study the effect of fetal stem cell (FSC) therapy on Grade Ⅰ and Ⅱ respiratory failure in patients with amyotrophic lateral sclerosis (ALS) and muscular dystrophy (MD).
Methods: A comparative study was conducted on 41 patients with Grade Ⅰ or Ⅱ respiratory failure (RF) resulting from ALS or MD. The patients were divided into 4 groups according to the underlying disease and the degree of RF. Patients underwent combined treatment, including the experimental application of FSC therapy, and were examined before FSC treatment, and 6 months and 12 months after treatment.
Results: FSC treatment improved both subjective and objective breathing parameters as early as 6 months post-treatment. A significant increase in the forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁) was reported by all patients with grade Ⅰ RF linked to ALS and MD compared to baseline. Patient respiratory improvement was maintained over the next 6 months. Grade Ⅱ RF patients with MD reported a significant improvement in FVC 12 months after treatment.
Conclusions: Evidence for respiratory improvement was observed as early as 6 months in all patients after combined treatment including FSC therapy, and this was maintained for a further 6 months after therapy. In MD patients with Grade Ⅱ RF, treatment resulted in a significant FVC and FEV₁ increase within 6 months and downgrading to Grade Ⅰ RF within a year after FSC treatment.

Objectives: Nerve regeneration after peripheral nerve injury is a slow process with a limited degree of functional recovery, resulting in a high disability rate. Thus, accelerating the rate of nerve regeneration and improving the degree of nerve repair is a clinical challenge. This study aimed to investigate the role of growth factor gel combined with small-gap nerve anastomosis in the regeneration of sciatic nerve injury in rats. This was achieved by injecting nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) gel into a silicon chamber that bridged the transection of the nerve.
Methods: In 27 randomly chosen Sprague Dawley rats, a sharp blade was used to transect the right hind leg sciatic nerve. The rats were divided into 3 groups: in groups A and B, silicon tubes containing NGF and bFGF gel or saline, respectively, were used to bridge the nerve proximal and distal ends (3-mm gap), and in group C, the nerve proximal and distal ends were directly sutured. Eight weeks after surgery, the sciatic nerve function index, neural electrophysiology, and muscle wet weight as well as histological, ultrastructural, and immunohistochemical parameters were evaluated.
Results: The sciatic nerve function index, nerve conduction velocity, muscle wet weight, density of regenerated nerve fibers, and myelination in group A were better than those in group B or C, but the sciatic nerve function index, muscle wet weight, and thickness of myelination in the 3 groups were not significantly different (P > 0.05). There were no significant differences innerve conduction velocity between groups A and B (P > 0.05), but it was higher in both groups than that of group C (P < 0.05). The regenerated nerve fiber density in the 3 groups showed significant differences (P < 0.05).
Conclusions: Small-gap nerve anastomosis can provide a good regenerative microenvironment for rat sciatic nerve regeneration, and the combined strategy of growth factor gel with small-gap nerve anastomosis appears to have a superior effect on nerve repair.

For some patients with drug-resistant focal epilepsy, we usually select conventional surgical resection, which has brought better outcomes. However, others are not eligible for a conventional open surgical resection of the epileptogenic zone because of the proximity of a functional area or the implication of a larger epileptogenic network. Initially, stereoelectroencephalography (SEEG) exploration was a method of electroencephalography recording that was used in the presurgical evaluation of epileptic patients with complex epilepsy. Later, intracerebral electrodes used for SEEG were applied to produce radio frequency thermocoagulation (RF-TC) in epileptic patients. SEEG-guided RF-TC has produced some promising results, especially in the last dacade. Now, it has become popular as a palliative treatment to reduce seizure frequency in patients with drug-resistant focal epilepsy. This article presents a review of SEEG-guided RF-TC.

The skull provides protection and mechanical support, and acts as a container for the brain and its accessory organs. Some defects in the skull can fatally threaten human life. Many efforts have been taken to repair defects in the skull, among which cranioplasty is the most prominent technique. To repair the injury, numerous natural and artificial materials have been adopted by neurosurgeons. Many cranioprostheses have been tried in the past decades, from autoplast to bioceramics. Neurosurgeons have been evaluating their advantages and shortages through clinical practice. Among those prostheses, surgeons gradually prefer bionic ones due to their marvelous osteoconductivity, osteoinductivity, biocompatibility, and biodegradability. Autogeneic bone has been widely recognized as the “gold standard” for renovating large-sized bone defects. However, the access to this technique is restricted by limited availability and complications associated with its use. Many metal and polymeric materials with mechanical characteristics analogous to natural bones were consequently applied to cranioplasty. But most of them were unsatisfactory concerning osteoconductiion and biodegradability owe to their intrinsic properties. With the microstructures almost identical to natural bones, mineralized collagen has biological performance nearly identical to autogeneic bone, such as osteoconduction. Implants made of mineralized collagen can integrate themselves into the newly formed bones through a process called “creeping substitution”. In this review, the authors retrospect the evolution of skull repair material applied in cranioplasty. The ultimate skull repair material should have microstructure and bioactive qualities that enable osteogenesis induction and intramembranous ossification.

Objective: To study the influence of different microsurgical methods on surgical outcomes and complications, and to improve the surgical outcomes for trigeminal neuralgia. Methods: The clinical data of 109 patients with trigeminal neuralgia, who were treated with microsurgery, were analyzed retrospectively. All patients were divided into 3 groups according to surgical modality: the trigeminal neuralgia decompression group (TND group, 19 patients), the TND and rhizotomy group (rhizotomy group, 55 patients), and the TND and selective lesioning group (lesioning group, 35 patients). The mid-term and short-term effects of microsurgery, and the occurrences of complications, were compared between the 3 groups. Results: There were no statistical differences in the frequency of complications between the 3 groups (P>0.05). Eighty-four patients were followed up for 6 to 33 months. The rate of pain disappearance was found to be 94.4% in the TND group, and 100% in both the rhizotomy and lesioning groups; thus, no significant differences were found between these 3 groups (P>0.05). Additionally, 50% of the patients in the rhizotomy group and 3.6% of the patients in the lesioning group had facial numbness while no patients were affected with facial numbness in the TND group, and the differences between these 3 groups were significant (P<0.05). Conclusions: Microsurgery is effective and safe for trigeminal neuralgia. The use of TND, in combination with selective lesioning, ensures therapeutic efficacy and improves the quality of life in postoperative patients.

Objective: This study aimed to use a systematic approach to evaluate the current utilization, safety, and effectiveness of cell therapies for neurological diseases in human. And review the present regulations, considering United States (US) as a representative country, for cell transplantation in neurological disease and discuss the challenges facing the field of neurology in the coming decades. Methods: A detailed search was performed in systematic literature reviews of cellularbased therapies in neurological diseases, using PubMed, web of science, and clinical trials. Regulations of cell therapy products used for clinical trials were searched from the Food and Drug Administration (FDA) and the National Institutes of Health (NIH). Results: Seven most common types of cell therapies for neurological diseases have been reported to be relatively safe with varying degrees of neurological recovery. And a series of regulations in US for cellular therapy was summarized including preclinical evaluations, sourcing material, stem cell manufacturing and characterization, cell therapy product, and clinical trials. Conclusions: Stem cell-based therapy holds great promise for a cure of such diseases and will value a growing population of patients. However, regulatory permitting activity of the US in the sphere of stem cells, technologies of regenerative medicine and substitutive cell therapy are selective, theoretical and does not fit the existing norm and rules. Compiled well-defined regulations to guide the application of stem cell products for clinical trials should be formulated.