Cold water swimming pretreatment reduces cognitive deficits in a rat model of traumatic brain injury

A moderate stress such as cold water swimming can raise the tolerance of the body to potentially injurious events. However, little is known about the mechanism of beneficial effects induced by moderate stress. In this study, we used a classic rat model of traumatic brain injury to test the hypothesis that cold water swimming preconditioning improved the recovery of cognitive functions and explored the mechanisms. Results showed that after traumatic brain injury, pre-conditioned rats（cold water swimming for 3 minutes at 4℃） spent a significantly higher percent of times in the goal quadrant of cold water swim, and escape latencies were shorter than for non-pretreated rats. The number of circulating endothelial progenitor cells was significantly higher in pre-conditioned rats than those without pretreatment at 0, 3, 6 and 24 hours after traumatic brain injury. Immunohistochemical staining and Von Willebrand factor staining demonstrated that the number of CD34~＋ stem cells and new blood vessels in the injured hippocampus tissue increased significantly in pre-conditioned rats. These data suggest that pretreatment with cold water swimming could promote the proliferation of endothelial progenitor cells and angiogenesis in the peripheral blood and hippocampus. It also ameliorated cognitive deficits caused by experimental traumatic brain injury.

Risk factors for corticosteroid insufficiency during the sub-acute phase of acute traumatic brain injury

Hypothalamic-pituitary-adrenal axis dysfunction may lead to the occurrence of critical illness-related corticosteroid insufficiency.Critical illness-related corticosteroid insufficiency can easily occur after traumatic brain injury,but few studies have examined this occurrence.A multicenter,prospective,cohort study was performed to evaluate the function of the hypothalamic-pituitary-adrenal axis and the incidence of critical illness-related corticosteroid insufficiency during the sub-acute phase of traumatic brain injury.One hundred and forty patients with acute traumatic brain injury were enrolled from the neurosurgical departments of three tertiary-level hospitals in China,and the critical illness-related corticosteroid insufficiency incidence,critical-illness-related corticosteroid insufficiency-related risk factors,complications,and 28-day mortality among these patients was recorded.Critical illness-related corticosteroid insufficiency was diagnosed in patients with plasma total cortisol levels less than 10μg/dL(275.9 nM)on post-injury day 4 or when serum cortisol was insufficiently suppressed(less than 50%)during a dexamethasone suppression test on post-injury day 5.The results demonstrated that critical illness-related corticosteroid insufficiency occurred during the sub-acute phase of traumatic brain injury in 5.6%of patients with mild injury,22.5%of patients with moderate injury,and 52.2%of patients with severe injury.Traumatic brain injury-induced critical illness-related corticosteroid insufficiency was strongly correlated to injury severity during the sub-acute stage of traumatic brain injury.Traumatic brain injury patients with critical illness-related corticosteroid insufficiency frequently presented with hemorrhagic cerebral contusions,diffuse axonal injury,brain herniation,and hypotension.Differences in the incidence of hospital-acquired pneumonia,gastrointestinal bleeding,and 28-day mortality were observed between patients with and without critical illness-related corticosteroid insufficiency during the sub-acute phase of traumatic brain injury.Hypotension,brain-injury severity,and the types of traumatic brain injury were independent risk factors for traumatic brain injury-induced critical illness-related corticosteroid insufficiency.These findings indicate that critical illness-related corticosteroid insufficiency is common during the sub-acute phase of traumatic brain injury and is strongly associated with poor prognosis.The dexamethasone suppression test is a practical assay for the evaluation of hypothalamic-pituitary-adrenal axis function and for the diagnosis of critical illness-related corticosteroid insufficiency in patients with traumatic brain injury,especially those with hypotension,hemorrhagic cerebral contusions,diffuse axonal injury,and brain herniation.Sub-acute infection of acute traumatic brain injury may be an important factor associated with the occurrence and development of critical illness-related corticosteroid insufficiency.This study protocol was approved by the Ethics Committee of General Hospital of Tianjin Medical University,China in December 2011(approval No.201189).

Application of Keyhole Microneurosurgery in China

INTRODUCTIONMicroneurosurgery made its debut in the early 1960s. It became popular in the medical field and became a primary operation method in neurosurgery since it improved the efficacy of neurosurgery with a less surgery-related injury. Over the past five decades, the accumulation of experience of microsurgery, improvement of microsurgery techniques, refined micro-instruments, and advanced preoperative diagnostic imaging allowed the evolution of microneurosurgery techniques and further reduced surgery-related trauma.

Use of a compact high-definition two-dimensional exoscope in surgical treatment of large vestibular schwannoma

Background::Extra-corporeal video telescope operating monitor system provides a necessary instrument to perform high-precision neurosurgical procedures that could substitute or supplement the traditional surgical microscope.The present study was designed to evaluate a compact high-definition two-dimensional exoscope system for assisting in surgical removal of large vestibular schwannoma(VS),as an alternative to a binocular surgical microscope.Methods::Patients with Koos grade 3 and grade 4 VS undergoing surgery were enrolled in this prospective cohort study between January 2013 and June 2018.The demographics and tumor characteristics(size,Koos grade,composition[cystic or solid mass])were matched between the two groups of patients.The following outcome measurements were compared between the two groups:duration of surgery,volume of blood loss,extent of tumor resection,number of operating field adjustments,pre-and post-operative facial and cochlear nerve function evaluated at 3 months post-surgery,complications and surgeons’comfortability.Results::A total of 81 patients received tumor resection through the retrosigmoid approach under either an exoscope(cases,n=39)or a surgical microscope(control,n=42).Patients in the two groups had comparable tumor location(P=0.439),Koos grading(P=0.867),and composition(P=0.891).While no significant differences in the duration of surgery(P=0.172),extent of tumor resection(P=0.858),facial function(P=0.838),and hearing ability(P=1.000),patients operated on under an exoscope had less blood loss(P=0.036)and a fewer field adjustments(P<0.001).Both primary and assistant surgeons reported a high level of comfort operating under the exoscope(P=0.001 and P<0.001,respectively).Conclusions::The compact high-definition two-dimensional exoscope system provides a safe and efficient means to assist in removing large VSs,as compared to a surgical microscope.After the acquaintance with a visual perception through a dynamic hint and stereoscopically viewing corresponding to the motion parallax,the exoscope system provided a comfortable,high-resolution visualization without compromising operational efficiency and patient safety.