Objective:Microvascular decompression(MVD)is the gold standard for treating drug-resistant classic trigeminal neuralgia(dcTN),with endoscopy enhancing surgical precision through improved visualization.This study evalu...Objective:Microvascular decompression(MVD)is the gold standard for treating drug-resistant classic trigeminal neuralgia(dcTN),with endoscopy enhancing surgical precision through improved visualization.This study evaluates the efficacy of fully endoscopic MVD for dcTN and presents our early experience.Methods:This retrospective study included patients with dcTN who underwent fully endoscopic MVD in the Department of Neurosurgery,the First Affiliated Hospital,Zhejiang University School of Medicine from November 2020 to February 2023.We recorded basic patient clinical information,clinical outcomes,offending vessels,complications,and recurrences,and assessed outcomes via the Barrow Neurological Institute(BNI)pain intensity score and the numeric rating scale(NRS)score.Results:All 42 patients had dcTN with preoperative BNI scores of V and NRS scores of 8e10.Endoscopic visualization enabled the precise identification of neurovascular conflicts,including small and deeply located vessels.Immediately after surgery,90.5%of patients achieved complete pain relief(BNI score of I,NRS score of 0).At the final follow-up,85.7%of patients had complete pain relief.All patients’pain was significantly relieved at immediate after surgery(0 vs.9,p<0.001)and at the final follow-up(0 vs.9,p<0.001),with lower NRS scores.Complications,including vertigo,headache,and transient facial numbness,occurred in 14.4%of patients and were manageable.展开更多
In this editorial,the authors of this paper comment on the article by Bokov et al published in the recent issue of World Journal of Orthopedics.We reviewed a general overview of oblique lumbar interbody fusions(OLIF)a...In this editorial,the authors of this paper comment on the article by Bokov et al published in the recent issue of World Journal of Orthopedics.We reviewed a general overview of oblique lumbar interbody fusions(OLIF)and lateral lumbar interbody fusions(LLIF),their indications and complications as an increasingly popular minimally invasive technique to address several lumbar pathologies.This editorial thoroughly discusses and reviews the literature regarding factors affecting outcomes of indirect decompression utilized through OLIF and LLIF procedures.Several parameters play a critical role in patient outcomes including restoration of disc height,foraminal height,central canal squared,and foraminal area.The indirect decompression allows for unbuckling of the ligamentum flavum which can significantly decompress the neural elements as well as aid in reduction of spondylolisthesis.However,the authors further highlight the limitations of indirect decompression and factors that may predict unsuccessful outcomes including bony foraminal stenosis,severe central canal stenosis,and osteoporosis.As a result,failure of indirect decompression can lead to persistent pain,radiculopathy and unsatisfied patients.Spinal surgeons may be left to reimage patients and consider additional procedures with direct decompression.展开更多
Dear Editor,Ocular decompression retinopathy(ODR),which manifests as diffuse retinal hemorrhage occurring abruptly in multiple locations,including the subretinal,intraretinal,and preretinal spaces,is a rare complicati...Dear Editor,Ocular decompression retinopathy(ODR),which manifests as diffuse retinal hemorrhage occurring abruptly in multiple locations,including the subretinal,intraretinal,and preretinal spaces,is a rare complication after glaucoma surgery and is caused by sudden,iatrogenic lowering of intraocular pressure(IOP).Implicated procedures include glaucoma drainage implantation,trabeculectomy,iridotomy,and even cataract surgery[1].One report described a case of ocular decompression management following uncomplicated cataract surgery with no posterior capsular rupture or other intraoperative complications[2].Here,we report a rare case of ODR triggered by phacoemulsification and the use of systemic chemotherapeutic drugs in a patient with primary acute angleclosure glaucoma(PACG).The case not only improves our understanding of potential side effects of chemotherapeutic drugs on ophthalmic surgery but may also serve as a reference for clinicians in the management of patients with glaucoma with similar medical histories.展开更多
Dear Editor,We present the first time,a case of a patient developed cerebrospinal fluid(CSF)leak and pneumocranium following optic canal decompression(OCD).INTRODUCTION Indirect traumatic optic neuropathy(ITON)impairs...Dear Editor,We present the first time,a case of a patient developed cerebrospinal fluid(CSF)leak and pneumocranium following optic canal decompression(OCD).INTRODUCTION Indirect traumatic optic neuropathy(ITON)impairs visual functions and quality of life.Endoscopic transnasal optic canal decompression(ETOCD)is one of the standard treatment strategies for the ITON.During the ETOCD,the optic nerve sheath are usually incised for sufficient decompression of optic nerve after removal of optic canal,which is associated with complications like CSF leakage,ophthalmic artery injury,and optic nerve injury[1].Generally,the mild CSF leak is common and can heal spontaneously using conventional treatment,the severe CSF leak requires surgical repair[2].展开更多
BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highl...BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical relevance.AIM To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar spine.METHODS This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal segment.Patients underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw fixation.Radiographic results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical results.RESULTS After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment height.In patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root compression.The critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 respectively.CONCLUSION Indirect decompression employing anterior reconstruction is achieved by the increase in disc height along the posterior boarder and reduction of the slipped vertebrae in patients with degenerative spondylolisthesis.Vertebral canal square below 80 mm2 and lateral recess depth less than 3 mm are associated with indirect decompression failures that require direct microsurgical decompression.展开更多
Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to...Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to be resected colon segment” was cut at its lower end, then the proximal cut end was put into a plastic bag which was adhered to one side of the operating table. After releasing the clamp, the content could ?ow into this bag. The operator could squeeze the bowel with two hands by turns, from proximal to farness, and from small bowel to large bowel, until the entire bowel content was fully discharged. Then the upper end of this “to be resected colon segment” was cut, and was removed together with the plastic bag. Results: 31 cases of left colon cancer with acute obstruction were decompressed with this technique. They all recovered smoothly, without anastomosis ?stula. Another 6 cases of hepatic seg- mentectomy with incidental colonectomy were decompressed with this technique and had the same results. This technique was also used in di?erent kinds of acute small intestinal obstruction and gained satisfactory results. Conclusion: This technique could be considered as the preferable choice for intraoperative enteral decompression.展开更多
With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored ha...With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored has increased dramatically. The use of compression techniques for these bitstream files is emerging as a key strategy to alleviate the burden on storage resources. Due to the severe resource constraints of space-based electronics and the unique application environment, the simplicity, efficiency and robustness of the decompression circuitry is also a key design consideration. Through comparative analysis current bitstream file compression technologies, this research suggests that the Lempel Ziv Oberhumer (LZO) compression algorithm is more suitable for satellite applications. This paper also delves into the compression process and format of the LZO compression algorithm, as well as the inherent characteristics of configuration bitstream files. We propose an improved algorithm based on LZO for bitstream file compression, which optimises the compression process by refining the format and reducing the offset. Furthermore, a low-cost, robust decompression hardware architecture is proposed based on this method. Experimental results show that the compression speed of the improved LZO algorithm is increased by 3%, the decompression hardware cost is reduced by approximately 60%, and the compression ratio is slightly reduced by 0.47%.展开更多
Introduction: Stroke is a worldwide leading cause of mortality and disability, and there are substantial economic costs for post-stroke. A large hemispheric ischemic stroke is a severe form of stroke that may occur in...Introduction: Stroke is a worldwide leading cause of mortality and disability, and there are substantial economic costs for post-stroke. A large hemispheric ischemic stroke is a severe form of stroke that may occur in up to 10% of stroke cases. In these cases, decompressive craniectomy (DC) is an effective strategy to reduce early case fatality. In this study, the authors present their experience in the management of large hemispheric stroke in patients who underwent decompressive craniectomy. Patients and Methods: This study is a retrospective analysis of 9 patients who underwent decompressive craniotomy for large hemispheric stroke from February 2021 to January 2024. Demographic, clinical, and radiologic variables were collected from the hospital archives. All patients underwent head CT scan or MRI showing the involvement of the majority or complete middle cerebral artery distribution area. Hemicraniectomy with duraplasty was the main surgical procedure. The mortality and the outcome using Modified Rankin Scale (mRS) were reported. Results: A total of 9 patients with large hemispheric stroke who underwent DC were reviewed retrospectively. The mean age was 53 years with extremes of 39- and 67-year-old. There were 6 males and 3 females. The main risk factors of stroke were hypertension and diabetes in 5 and 3 cases, respectively. The large craniectomy was made and the dura was opened in the stellate fashion. Duraplasty was performed using epicrane in 7 patients and fascia lata aponeurosis in 2 patients. In the postoperative course, 4 (44%) patients died in 1 month and the mortality rate was 66.6% in 6 months. Conclusion: Decompressive craniectomy is a life-saving procedure used to manage cerebral edema after stroke onset. In our study, the high mortality rate could be explained by many factors, such as patient selection criteria and timing of surgery. Early surgery within the first 48 hours in patients less than 60 years old with large hemispheric stroke is recommended.展开更多
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio...The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.展开更多
Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive da...Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive data vulnerable to unauthorized access and misuse.With the exponential growth of digital data,robust security measures are essential.Data encryption,a widely used approach,ensures data confidentiality by making it unreadable and unalterable through secret key control.Despite their individual benefits,both require significant computational resources.Additionally,performing them separately for the same data increases complexity and processing time.Recognizing the need for integrated approaches that balance compression ratios and security levels,this research proposes an integrated data compression and encryption algorithm,named IDCE,for enhanced security and efficiency.Thealgorithmoperates on 128-bit block sizes and a 256-bit secret key length.It combines Huffman coding for compression and a Tent map for encryption.Additionally,an iterative Arnold cat map further enhances cryptographic confusion properties.Experimental analysis validates the effectiveness of the proposed algorithm,showcasing competitive performance in terms of compression ratio,security,and overall efficiency when compared to prior algorithms in the field.展开更多
BACKGROUND Traumatic subdural effusion is a common complication of traumatic brain injury,especially after decompressive craniectomy(DC).For neurosurgeons,early diagnosis and timely treatment are particularly importan...BACKGROUND Traumatic subdural effusion is a common complication of traumatic brain injury,especially after decompressive craniectomy(DC).For neurosurgeons,early diagnosis and timely treatment are particularly important,which can help improve patient prognosis and enhance quality of life.CASE SUMMARY A 47 year old male underwent DC for traumatic brain herniation.After surgery,he developed stubborn subdural effusion(SDE)on the contralateral side and underwent multiple subdural drilling and drainage surgeries,but only temporarily improved the patient’s symptoms.After the final cranioplasty,the contralateral SDE completely disappeared.The patient did not experience any new contralateral neurological dysfunction,and the Glasgow prognostic score was 11 points(E4V1M6).CONCLUSION For neurosurgeons,accurate assessment of the condition is necessary when treating patients with stubborn SDE after DC surgery,and timely cranioplasty can be performed to avoid multiple surgeries.This is a safe and effective surgical method for treating traumatic subdural effusion.展开更多
Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function a...Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function after surgery,with spinal cord ischemia–reperfusion injury(SCII)identified as the primary cause.Spinal cord compression results in local ischemia and blood perfusion following decompression is fundamental to SCII.However,owing to inadequate perioperative blood flow monitoring,direct evidence regarding the occurrence of SCII after decompression is lacking.The objective of this study was to establish a suitable animal model for investigating the underlying mechanism of spinal cord ischemia–reperfusion injury following decom-pression surgery for degenerative cervical myelopathy(DCM)and to elucidate alterations in neurological function and local blood flow within the spinal cord before and after decompression.Methods:Twenty-four Sprague–Dawley rats were allocated to three groups:the DCM group(cervical compression group,with implanted compression material in the spinal canal,n=8),the DCM-D group(cervical decompression group,with removal of compression material from the spinal canal 4 weeks after implantation,n=8),and the SHAM group(sham operation,n=8).Von Frey test,forepaw grip strength,and gait were assessed within 4 weeks post-implantation.Spinal cord compression was evaluated using magnetic resonance imaging.Local blood flow in the spinal cord was monitored during the perioperative decompression.The rats were sacrificed 1 week after decompression to observe morphological changes in the compressed or decompressed segments of the spinal cord.Additionally,NeuN expression and the oxidative damage marker 8-oxoG DNA were analyzed.Results:Following spinal cord compression,abnormal mechanical pain worsened,and a decrease in forepaw grip strength was observed within 1–4 weeks.Upon decompression,the abnormal mechanical pain subsided,and forepaw grip strength was restored;however,neither reached the level of the sham operation group.Decompression leads to an increase in the local blood flow,indicating improved perfusion of the spinal cord.The number of NeuN-positive cells in the spinal cord of rats in the DCM-D group exceeded that in the DCM group but remained lower than that in the SHAM group.Notably,a higher level of 8-oxoG DNA expression was observed,suggesting oxidative stress following spinal cord decompression.Conclusion:This model is deemed suitable for analyzing the underlying mechanism of SCII following decompressive cervical laminectomy,as we posit that the obtained results are comparable to the clinical progression of degenerative cervical myelopathy(DCM)post-decompression and exhibit analogous neurological alterations.Notably,this model revealed ischemic reperfusion in the spinal cord after decompression,concomitant with oxidative damage,which plausibly underlies the neurological deterioration observed after decompression.展开更多
An additional hot compression process was applied to a dilute Mg−Mn−Zn alloy post-extrusion.The alloy was extruded at 150°C with an extrusion ratio of 15:1 and subsequently hot-compressed at 180°C with a tru...An additional hot compression process was applied to a dilute Mg−Mn−Zn alloy post-extrusion.The alloy was extruded at 150°C with an extrusion ratio of 15:1 and subsequently hot-compressed at 180°C with a true strain of 0.9 along the extrusion direction.The microstructure,mechanical properties and thermal conductivity of as-extruded and as-hot compressed Mg−Mn−Zn alloys were investigated using optical microscopy,scanning electron microscopy,electron backscattering diffraction,and transmission electron microscopy.The aim was to concurrently enhance both strength and thermal conductivity by fostering uniform and refined microstructures while mitigating basal texture intensity.Substantial improvements were observed in yield strength(YS),ultimate tensile strength(UTS),and elongation(EL),with increase of 77%,53% and 10%,respectively.Additionally,thermal conductivity demonstrated a notable enhancement,rising from 111 to 125 W/(m·K).The underlying mechanism driving these improvements through the supplementary hot compression step was thoroughly elucidated.This study presents a promising pathway for the advancement of Mg alloys characterized by superior thermal and mechanical properties.展开更多
The asymmetric creep aging behaviors of a pre-treated Al-Zn-Mg-Cu alloy under high and low stresses have been investigated for high precision creep age forming application of aluminum integral panels.With the increase...The asymmetric creep aging behaviors of a pre-treated Al-Zn-Mg-Cu alloy under high and low stresses have been investigated for high precision creep age forming application of aluminum integral panels.With the increase of applied stress,the creep strains under the tensile stresses are higher than those of compressive stresses and the asymmetry of creep strain is more obvious.However,the mechanical properties of tensile stress creep aged samples are lower than those of compressive stress creep aged samples.Dislocation density,dislocation moving velocity and the proportion of precipitates directly lead to the asymmetry of creep strain and mechanical properties after tensile-compressive creep aging process.In addition,the tensile and compressive stresses have little effect on the width of the precipitate-free zone(PFZ).It indicates that in the high stress creep age forming process of the pretreated Al-Zn-Mg-Cu alloy,the tensile stress promotes the dislocation motion to obtain a better creep strain but weakens its mechanical properties compared with the compressive stress.In the field of civil aviation aircraft component manufacturing,the introduction of tension and compression stress asymmetry into the creep constitutive model may improve the accuracy of creep age forming components.展开更多
Objective:To observe the effect of recombinant human bone morphogenetic protein 2/polylactide-co-glycolic acid(rhBMP-2/PLGA) with core decompression on repair of rabbit femoral head necrosis.Methods:Bilateral femoral ...Objective:To observe the effect of recombinant human bone morphogenetic protein 2/polylactide-co-glycolic acid(rhBMP-2/PLGA) with core decompression on repair of rabbit femoral head necrosis.Methods:Bilateral femoral head necrosis models of rabbit were established by steroid injection.A total of 48 rabbits(96 femoral head necrosis) were randomly divided into 4groups:Group A,control group with12 rabbits,24 femoral head necrosis;Group B,treated with rhBMP-2/PLCA implantation after core depression,with 12 rabbits,24 femoral head necrosis;Group C,treated with rhBMP-2 implantation after core depression,with 12 rabbits,24 femoral head necrosis;Croup D treated with core depression group without implantation,with 12 rabbits,24 femoral head necrosis.All animals were sacrificed after 12 weeks.The ability of repairing bone defect was evaluated by X-ray radiograph.Bone mineral density analysis of the defect regions were used to evaluate the level of ossification.The morphologic change and bone formation was assessed by HE staining.The angiogenesis was evaluated by VEGF immunohistochemistry.Results:The osteogenetic ability and quality of femoral head necrosis in group B were better than those of other groups after 12 weeks by X-ray radiograph and morphologic investigation.And the angiogenesis in group B was better than other groups.Group C had similar osteogenetic quality of femoral head necrosis and angiogenesis with group D.Conclusions:The treatment of rhBMP-2/PLCA implantation after core depression can promote the repair of rabbit femoral head necrosis.It is a promising and efficient synthetic bone material to treat the femoral head necrosis.展开更多
AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and...AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and sixteen patients submitted to operations associated with colorectostorny from January 2004 to September 2005 were randomized to two groups: In experimental group (n = 161), the nasogastric tube was removed after the operation from 12 to 24 hours and was promised immediately oral feeding; In control group (n = 155), the nasogastric tube was maintained until the passage of flatus per rectum. Variables assessed included the time to first passage of flatus, the time to first passage of stool, the time elapsed postoperative stay, and postoperative complications such as anastornotic leakage, acute dilation of stomach, wound infection and dehiscense, fever, pulmonary infection and pharyngolaryngitis. RESULTS: The median and average days to the first passage of flatus (3.0±0.9 vs 3.6±1.2, P〈0.001), the first passage of stool (4.1± 1.1 vs 4.8±1.4 P〈0.001) and the length of postoperative stay (8.4±3.4 vs 9.6±5.0, P〈0.05) were shorter in the experimental group than in the control group. The postoperative complications such as anastomotic leakage (1.24% vs 2.58%), acute dilation of stomach (1.86% vs 0.06%) and wound complications (2.48% vs 1.94%) were similar in the groups, but fever (3.73% vs 9.68%, P〈0.05), pulmonary infection (0.62% vs 4.52%, P〈0.05) and pharyngolaryngitis (3.11% vs 23.23%, P〈0.001) were much more in the control group than in the experimental group. CONCLUSION: The present study shows that applicationof gastrointestinal decompression after colorectostomy can not effectively reduce postoperative complications. On the contrary, it may increase the incidence rate of fever, pharyngolaryngitis and pulmonary infection. These strategies of early removing gastrointestinal decompression and early oral feeding in the patients undergoing colorectostomy are feasible and safe and associated with reduced postoperative discomfort and can accelerate the return of bowel function and improve rehabilitation.展开更多
AIM: To report the effects of intravenous high-dose glucocorticoids(iv GC) and orbital decompression(OD) surgery for treatment of sight-threatening thyroid-associated ophthalmopathy(TAO).METHODS: A retrospective revie...AIM: To report the effects of intravenous high-dose glucocorticoids(iv GC) and orbital decompression(OD) surgery for treatment of sight-threatening thyroid-associated ophthalmopathy(TAO).METHODS: A retrospective review of medical records from patients with sight-threatening TAO [definite or highly suspected dysthyroid optic neuropathy(DON)] treated with iv GC(60 cases) and OD(25 cases) was conducted at the Zhongshan Ophthalmic Center between January 2001 and January 2009. Patients were initially treated with iv GC(iv GC group). If no significant improvement in visual function was obtained, they then received OD surgery(OD group). The pre-versus post-treatment efficacies of either iv GC or OD in these patients were assessed using several indices, including visual acuity, intraocular pressure, ocular alignment, ocular motility, and exophthalmos. RESULTS: Nighty-one eyes had definite DON while 79 were considered to have highly suspected DON. In the iv GC group, 51 individuals(85.0%) eventually demonstrated normal vision, while 10 patients(16.7%) demonstrated a reduction in deviation(P<0.01), and 35 cases(58.3%) showed slight improvements in ocular motility(P<0.01). In OD group, visual acuity improved in 24 cases(96.0%, P<0.01) and all patients showed varying reductions of exophthalmos(mean: 4.35±1.13 mm, P<0.01). Eight cases(32.0%) experienced an 8-15 PD reduction of deviation and ocular motility improved in 12 cases(48.0%), while 3 patients(12.0%) developed new-onset strabismus with diplopia post-surgically(P<0.01). Patients were followed up at an average of 1.55±1.07 y. CONCLUSION: Both iv GC and OD show good therapeutic efficacy in the treatment of sight-threatening TAO. Thepresence of extremely poor eyesight(≥0.5 log MAR) was corrected in some patients with iv GC alone, thus sparing these patients from subsequent OD surgery. In patients who were refractory to steroids, subsequent OD surgery often provided satisfactory outcomes, however, new-onset strabismus with diplopia was observed in 12.0% of these cases.展开更多
BACKGROUND:Excessive hepatocyte apoptosis and bile lakes in severe obstructive jaundice might impair liver functions.Although decompression of the bile duct has been reported to improve liver functions in animal studi...BACKGROUND:Excessive hepatocyte apoptosis and bile lakes in severe obstructive jaundice might impair liver functions.Although decompression of the bile duct has been reported to improve liver functions in animal studies,the mechanism of obstruction differs from that in humans.This study aimed to determine the profiles of hepatocyte apoptosis and bile lakes following bile duct decompression in patients with severe obstructive jaundice in the clinical setting.METHODS:We conducted a 'before and after study' on severe obstructive jaundice patients as a model of inhibition of the excessive process by bile duct decompression.Specimens of liver biopsies were taken before and after decompression of the bile duct and then stained by terminal deoxynucleotide transferase-mediated dUTP nick end-labeling(TUNEL) to identify hepatocyte apoptosis and by hematoxilin-eosin(HE) to identify bile lakes.All measurements were independently done by 2 observers.RESULTS:Twenty-one severe obstructive jaundice patients were included.In all patients,excessive hepatocyte apoptosis and bile lakes were apparent.After decompression,the hepatocyte apoptosis index decreased from 53.1(SD 105) to 11.7(SD 13.6)(P<0.05),and the bile lakes from 23.6(SD 14.8) to 10.9(SD 6.9)(P<0.05).CONCLUSION:Bile duct decompression improves hepatocyte apoptosis and bile lakes in cases of severe obstructive jaundice,similar to the findings in animal studies.展开更多
U-shaped sacral fractures are rare and often difficult to diagnose primarily due to the difficulty in obtaining adequate imaging and the severe associated injuries. These fractures are highly unstable and frequently c...U-shaped sacral fractures are rare and often difficult to diagnose primarily due to the difficulty in obtaining adequate imaging and the severe associated injuries. These fractures are highly unstable and frequently cause neurological deficits. The majority of surgeons have limited experience in management of U-shaped sacral fractures. No standard treatment protocol for U-shaped sacral fractures has been available till now. This study aimed to examine the management of U-shaped sacral fractures and the early outcomes. Clinical data of 15 consecutive patients with U-shaped sacral fracture who were admitted to our trauma center between 2009 and 2014 were retrospectively analyzed. Demographics, fracture classification, mechanism of injury and operative treatment and deformity angle were assessed. All the patients were treated with lumbopelvic fixation or (and) sacral decompression. EQ-5d score was applied to evaluate the patients' quality of life. Of the 15 consecutive patients with U-shaped sacral fracture, the mean age was 28.8 years (range: 15-55 years) at the time of injury. There were 6 females and 9 males. The mean follow- up time was 22.7 months (range: 9-47 months) and mean full weight-bearing time was 9.9 weeks (range: 8-14 weeks). Ten patients received lumbopelvic fixation and sacral decompression, one lombosacral fixation, and 4 merely sacral decompression due to delayed diagnosis or surgery. The post-operation deformity angle (mean 27.87°, and range: 8°-90°) of the sacrum was smaller than that pre-operation (mean 35.67; range: 15-90) with no significance difference noted. At the latest follow-up, all patients obtained neurological recovery with different extents. Visual analogue score (VAS) was reduced from preoperative 7.07 (range: 5-9) to postoperetive 1.93 (range: 1-3). All patients could walk without any aid after treatment. Eight patients were able to care for themselves and undertook some daily activities. Five patients had returned to work full time. In conclusion, lumbopelvic fixation is an effective method for stabilization of U-shaped sacral fractures with fewer complications developed. Effective reduction and firm fixation are the prerequisite of early mobilization and neurological recovery. Sacral decompression effectively promotes neurological recovery even in patients with old U-shaped sacral fractures.展开更多
AIM: To evaluate the long-term results of different orbital decompression techniques performed in patients with Graves' ophthalmopathy(GO).METHODS: Totally 170 cases with GO underwent orbital decompression betwee...AIM: To evaluate the long-term results of different orbital decompression techniques performed in patients with Graves' ophthalmopathy(GO).METHODS: Totally 170 cases with GO underwent orbital decompression between 1994 and 2014. Patients were divided into 4 groups as medial-inferior, mediallateral(balanced), medial-lateral-inferior, and lateral only according to the applied surgical technique. Surgical indications, regression degrees on Hertel exophthalmometer, new-onset diplopia in the primary gaze and new-onset gaze-evoked diplopia after surgery and visual acuity in cases with dysthyroid optic neuropathy(DON) were compared between different surgical techniques.RESULTS: The study included 248 eyes of 149 patients. The mean age for surgery was 42.3±13.2 y. DON was the surgical indication in 36.6% of cases, and three-wall decompression was the most preferred technique in these cases. All types of surgery significantly decrease the Hertel values(P〈0.005). Balanced medial-lateral, and only lateral wall decompression caused the lowest rate of postoperative new-onset diplopia in primary gaze. The improvement of visual acuity in patients with DON did not significantly differ between the groups(P=0.181). CONCLUSION: The study show that orbital decompression surgery has safe and effective long term results for functional and cosmetic rehabilitation of GO. It significantly reduces Hertel measurements in disfiguring proptosis and improves visual functions especially in DON cases.展开更多
基金supported by financial assistance from the Zhejiang Provincial Natural Science Foundation of China under Grant No.LY18H160020.
文摘Objective:Microvascular decompression(MVD)is the gold standard for treating drug-resistant classic trigeminal neuralgia(dcTN),with endoscopy enhancing surgical precision through improved visualization.This study evaluates the efficacy of fully endoscopic MVD for dcTN and presents our early experience.Methods:This retrospective study included patients with dcTN who underwent fully endoscopic MVD in the Department of Neurosurgery,the First Affiliated Hospital,Zhejiang University School of Medicine from November 2020 to February 2023.We recorded basic patient clinical information,clinical outcomes,offending vessels,complications,and recurrences,and assessed outcomes via the Barrow Neurological Institute(BNI)pain intensity score and the numeric rating scale(NRS)score.Results:All 42 patients had dcTN with preoperative BNI scores of V and NRS scores of 8e10.Endoscopic visualization enabled the precise identification of neurovascular conflicts,including small and deeply located vessels.Immediately after surgery,90.5%of patients achieved complete pain relief(BNI score of I,NRS score of 0).At the final follow-up,85.7%of patients had complete pain relief.All patients’pain was significantly relieved at immediate after surgery(0 vs.9,p<0.001)and at the final follow-up(0 vs.9,p<0.001),with lower NRS scores.Complications,including vertigo,headache,and transient facial numbness,occurred in 14.4%of patients and were manageable.
文摘In this editorial,the authors of this paper comment on the article by Bokov et al published in the recent issue of World Journal of Orthopedics.We reviewed a general overview of oblique lumbar interbody fusions(OLIF)and lateral lumbar interbody fusions(LLIF),their indications and complications as an increasingly popular minimally invasive technique to address several lumbar pathologies.This editorial thoroughly discusses and reviews the literature regarding factors affecting outcomes of indirect decompression utilized through OLIF and LLIF procedures.Several parameters play a critical role in patient outcomes including restoration of disc height,foraminal height,central canal squared,and foraminal area.The indirect decompression allows for unbuckling of the ligamentum flavum which can significantly decompress the neural elements as well as aid in reduction of spondylolisthesis.However,the authors further highlight the limitations of indirect decompression and factors that may predict unsuccessful outcomes including bony foraminal stenosis,severe central canal stenosis,and osteoporosis.As a result,failure of indirect decompression can lead to persistent pain,radiculopathy and unsatisfied patients.Spinal surgeons may be left to reimage patients and consider additional procedures with direct decompression.
文摘Dear Editor,Ocular decompression retinopathy(ODR),which manifests as diffuse retinal hemorrhage occurring abruptly in multiple locations,including the subretinal,intraretinal,and preretinal spaces,is a rare complication after glaucoma surgery and is caused by sudden,iatrogenic lowering of intraocular pressure(IOP).Implicated procedures include glaucoma drainage implantation,trabeculectomy,iridotomy,and even cataract surgery[1].One report described a case of ocular decompression management following uncomplicated cataract surgery with no posterior capsular rupture or other intraoperative complications[2].Here,we report a rare case of ODR triggered by phacoemulsification and the use of systemic chemotherapeutic drugs in a patient with primary acute angleclosure glaucoma(PACG).The case not only improves our understanding of potential side effects of chemotherapeutic drugs on ophthalmic surgery but may also serve as a reference for clinicians in the management of patients with glaucoma with similar medical histories.
文摘Dear Editor,We present the first time,a case of a patient developed cerebrospinal fluid(CSF)leak and pneumocranium following optic canal decompression(OCD).INTRODUCTION Indirect traumatic optic neuropathy(ITON)impairs visual functions and quality of life.Endoscopic transnasal optic canal decompression(ETOCD)is one of the standard treatment strategies for the ITON.During the ETOCD,the optic nerve sheath are usually incised for sufficient decompression of optic nerve after removal of optic canal,which is associated with complications like CSF leakage,ophthalmic artery injury,and optic nerve injury[1].Generally,the mild CSF leak is common and can heal spontaneously using conventional treatment,the severe CSF leak requires surgical repair[2].
文摘BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical relevance.AIM To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar spine.METHODS This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal segment.Patients underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw fixation.Radiographic results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical results.RESULTS After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment height.In patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root compression.The critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 respectively.CONCLUSION Indirect decompression employing anterior reconstruction is achieved by the increase in disc height along the posterior boarder and reduction of the slipped vertebrae in patients with degenerative spondylolisthesis.Vertebral canal square below 80 mm2 and lateral recess depth less than 3 mm are associated with indirect decompression failures that require direct microsurgical decompression.
文摘Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to be resected colon segment” was cut at its lower end, then the proximal cut end was put into a plastic bag which was adhered to one side of the operating table. After releasing the clamp, the content could ?ow into this bag. The operator could squeeze the bowel with two hands by turns, from proximal to farness, and from small bowel to large bowel, until the entire bowel content was fully discharged. Then the upper end of this “to be resected colon segment” was cut, and was removed together with the plastic bag. Results: 31 cases of left colon cancer with acute obstruction were decompressed with this technique. They all recovered smoothly, without anastomosis ?stula. Another 6 cases of hepatic seg- mentectomy with incidental colonectomy were decompressed with this technique and had the same results. This technique was also used in di?erent kinds of acute small intestinal obstruction and gained satisfactory results. Conclusion: This technique could be considered as the preferable choice for intraoperative enteral decompression.
基金supported in part by the National Key Laboratory of Science and Technology on Space Microwave(Grant Nos.HTKJ2022KL504009 and HTKJ2022KL5040010).
文摘With the increase in the quantity and scale of Static Random-Access Memory Field Programmable Gate Arrays (SRAM-based FPGAs) for aerospace application, the volume of FPGA configuration bit files that must be stored has increased dramatically. The use of compression techniques for these bitstream files is emerging as a key strategy to alleviate the burden on storage resources. Due to the severe resource constraints of space-based electronics and the unique application environment, the simplicity, efficiency and robustness of the decompression circuitry is also a key design consideration. Through comparative analysis current bitstream file compression technologies, this research suggests that the Lempel Ziv Oberhumer (LZO) compression algorithm is more suitable for satellite applications. This paper also delves into the compression process and format of the LZO compression algorithm, as well as the inherent characteristics of configuration bitstream files. We propose an improved algorithm based on LZO for bitstream file compression, which optimises the compression process by refining the format and reducing the offset. Furthermore, a low-cost, robust decompression hardware architecture is proposed based on this method. Experimental results show that the compression speed of the improved LZO algorithm is increased by 3%, the decompression hardware cost is reduced by approximately 60%, and the compression ratio is slightly reduced by 0.47%.
文摘Introduction: Stroke is a worldwide leading cause of mortality and disability, and there are substantial economic costs for post-stroke. A large hemispheric ischemic stroke is a severe form of stroke that may occur in up to 10% of stroke cases. In these cases, decompressive craniectomy (DC) is an effective strategy to reduce early case fatality. In this study, the authors present their experience in the management of large hemispheric stroke in patients who underwent decompressive craniectomy. Patients and Methods: This study is a retrospective analysis of 9 patients who underwent decompressive craniotomy for large hemispheric stroke from February 2021 to January 2024. Demographic, clinical, and radiologic variables were collected from the hospital archives. All patients underwent head CT scan or MRI showing the involvement of the majority or complete middle cerebral artery distribution area. Hemicraniectomy with duraplasty was the main surgical procedure. The mortality and the outcome using Modified Rankin Scale (mRS) were reported. Results: A total of 9 patients with large hemispheric stroke who underwent DC were reviewed retrospectively. The mean age was 53 years with extremes of 39- and 67-year-old. There were 6 males and 3 females. The main risk factors of stroke were hypertension and diabetes in 5 and 3 cases, respectively. The large craniectomy was made and the dura was opened in the stellate fashion. Duraplasty was performed using epicrane in 7 patients and fascia lata aponeurosis in 2 patients. In the postoperative course, 4 (44%) patients died in 1 month and the mortality rate was 66.6% in 6 months. Conclusion: Decompressive craniectomy is a life-saving procedure used to manage cerebral edema after stroke onset. In our study, the high mortality rate could be explained by many factors, such as patient selection criteria and timing of surgery. Early surgery within the first 48 hours in patients less than 60 years old with large hemispheric stroke is recommended.
基金financially supported by the National Natural Science Foundation of China(Nos.52174092,51904290,and 52374147)the Natural Science Foundation of Jiangsu Province,China(No.BK20220157)+2 种基金the Fundamental Research Funds for the Central Universities,China(No.2022YCPY0202)the National Key Research and Development Program of China(No.2023YFC3804204)the Major Program of Xinjiang Uygur Autonomous Region S cience and Technology(No.2023A01002)。
文摘The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.
基金the Deanship of Graduate Studies and Scientific Research at Qassim University for financial support(QU-APC-2025).
文摘Data compression plays a vital role in datamanagement and information theory by reducing redundancy.However,it lacks built-in security features such as secret keys or password-based access control,leaving sensitive data vulnerable to unauthorized access and misuse.With the exponential growth of digital data,robust security measures are essential.Data encryption,a widely used approach,ensures data confidentiality by making it unreadable and unalterable through secret key control.Despite their individual benefits,both require significant computational resources.Additionally,performing them separately for the same data increases complexity and processing time.Recognizing the need for integrated approaches that balance compression ratios and security levels,this research proposes an integrated data compression and encryption algorithm,named IDCE,for enhanced security and efficiency.Thealgorithmoperates on 128-bit block sizes and a 256-bit secret key length.It combines Huffman coding for compression and a Tent map for encryption.Additionally,an iterative Arnold cat map further enhances cryptographic confusion properties.Experimental analysis validates the effectiveness of the proposed algorithm,showcasing competitive performance in terms of compression ratio,security,and overall efficiency when compared to prior algorithms in the field.
文摘BACKGROUND Traumatic subdural effusion is a common complication of traumatic brain injury,especially after decompressive craniectomy(DC).For neurosurgeons,early diagnosis and timely treatment are particularly important,which can help improve patient prognosis and enhance quality of life.CASE SUMMARY A 47 year old male underwent DC for traumatic brain herniation.After surgery,he developed stubborn subdural effusion(SDE)on the contralateral side and underwent multiple subdural drilling and drainage surgeries,but only temporarily improved the patient’s symptoms.After the final cranioplasty,the contralateral SDE completely disappeared.The patient did not experience any new contralateral neurological dysfunction,and the Glasgow prognostic score was 11 points(E4V1M6).CONCLUSION For neurosurgeons,accurate assessment of the condition is necessary when treating patients with stubborn SDE after DC surgery,and timely cranioplasty can be performed to avoid multiple surgeries.This is a safe and effective surgical method for treating traumatic subdural effusion.
基金Wangjing Hospital Affiliated to China Academy of Chinese Medical Sciences,Grant/Award Number:WJYY-YJKT-2022-13。
文摘Background:Although decompression surgery is the optimal treatment for patients with severe degenerative cervical myelopathy(DCM),some individuals experience no improvement or even a decline in neurological function after surgery,with spinal cord ischemia–reperfusion injury(SCII)identified as the primary cause.Spinal cord compression results in local ischemia and blood perfusion following decompression is fundamental to SCII.However,owing to inadequate perioperative blood flow monitoring,direct evidence regarding the occurrence of SCII after decompression is lacking.The objective of this study was to establish a suitable animal model for investigating the underlying mechanism of spinal cord ischemia–reperfusion injury following decom-pression surgery for degenerative cervical myelopathy(DCM)and to elucidate alterations in neurological function and local blood flow within the spinal cord before and after decompression.Methods:Twenty-four Sprague–Dawley rats were allocated to three groups:the DCM group(cervical compression group,with implanted compression material in the spinal canal,n=8),the DCM-D group(cervical decompression group,with removal of compression material from the spinal canal 4 weeks after implantation,n=8),and the SHAM group(sham operation,n=8).Von Frey test,forepaw grip strength,and gait were assessed within 4 weeks post-implantation.Spinal cord compression was evaluated using magnetic resonance imaging.Local blood flow in the spinal cord was monitored during the perioperative decompression.The rats were sacrificed 1 week after decompression to observe morphological changes in the compressed or decompressed segments of the spinal cord.Additionally,NeuN expression and the oxidative damage marker 8-oxoG DNA were analyzed.Results:Following spinal cord compression,abnormal mechanical pain worsened,and a decrease in forepaw grip strength was observed within 1–4 weeks.Upon decompression,the abnormal mechanical pain subsided,and forepaw grip strength was restored;however,neither reached the level of the sham operation group.Decompression leads to an increase in the local blood flow,indicating improved perfusion of the spinal cord.The number of NeuN-positive cells in the spinal cord of rats in the DCM-D group exceeded that in the DCM group but remained lower than that in the SHAM group.Notably,a higher level of 8-oxoG DNA expression was observed,suggesting oxidative stress following spinal cord decompression.Conclusion:This model is deemed suitable for analyzing the underlying mechanism of SCII following decompressive cervical laminectomy,as we posit that the obtained results are comparable to the clinical progression of degenerative cervical myelopathy(DCM)post-decompression and exhibit analogous neurological alterations.Notably,this model revealed ischemic reperfusion in the spinal cord after decompression,concomitant with oxidative damage,which plausibly underlies the neurological deterioration observed after decompression.
基金financially supported by the National Key Research and Development Program of China(No.2022YFE0109600)the National Natural Science Foundation of China(No.52150710544)。
文摘An additional hot compression process was applied to a dilute Mg−Mn−Zn alloy post-extrusion.The alloy was extruded at 150°C with an extrusion ratio of 15:1 and subsequently hot-compressed at 180°C with a true strain of 0.9 along the extrusion direction.The microstructure,mechanical properties and thermal conductivity of as-extruded and as-hot compressed Mg−Mn−Zn alloys were investigated using optical microscopy,scanning electron microscopy,electron backscattering diffraction,and transmission electron microscopy.The aim was to concurrently enhance both strength and thermal conductivity by fostering uniform and refined microstructures while mitigating basal texture intensity.Substantial improvements were observed in yield strength(YS),ultimate tensile strength(UTS),and elongation(EL),with increase of 77%,53% and 10%,respectively.Additionally,thermal conductivity demonstrated a notable enhancement,rising from 111 to 125 W/(m·K).The underlying mechanism driving these improvements through the supplementary hot compression step was thoroughly elucidated.This study presents a promising pathway for the advancement of Mg alloys characterized by superior thermal and mechanical properties.
基金Project(2021YFB3400900)supported by the National Key R&D Program of ChinaProjects(51905551,52205435)supported by the National Natural Science Foundation of China Youth Foundation+1 种基金Project(2022ZZTS0196)supported by the Fundamental Research Founds for the Central Universities,ChinaProject(CX20220282)supported by the Hunan Provincial Innovation Foundation for Postgraduate,China。
文摘The asymmetric creep aging behaviors of a pre-treated Al-Zn-Mg-Cu alloy under high and low stresses have been investigated for high precision creep age forming application of aluminum integral panels.With the increase of applied stress,the creep strains under the tensile stresses are higher than those of compressive stresses and the asymmetry of creep strain is more obvious.However,the mechanical properties of tensile stress creep aged samples are lower than those of compressive stress creep aged samples.Dislocation density,dislocation moving velocity and the proportion of precipitates directly lead to the asymmetry of creep strain and mechanical properties after tensile-compressive creep aging process.In addition,the tensile and compressive stresses have little effect on the width of the precipitate-free zone(PFZ).It indicates that in the high stress creep age forming process of the pretreated Al-Zn-Mg-Cu alloy,the tensile stress promotes the dislocation motion to obtain a better creep strain but weakens its mechanical properties compared with the compressive stress.In the field of civil aviation aircraft component manufacturing,the introduction of tension and compression stress asymmetry into the creep constitutive model may improve the accuracy of creep age forming components.
基金supported by Shandong Province Natural Science Foundation of China:sd2018762872
文摘Objective:To observe the effect of recombinant human bone morphogenetic protein 2/polylactide-co-glycolic acid(rhBMP-2/PLGA) with core decompression on repair of rabbit femoral head necrosis.Methods:Bilateral femoral head necrosis models of rabbit were established by steroid injection.A total of 48 rabbits(96 femoral head necrosis) were randomly divided into 4groups:Group A,control group with12 rabbits,24 femoral head necrosis;Group B,treated with rhBMP-2/PLCA implantation after core depression,with 12 rabbits,24 femoral head necrosis;Group C,treated with rhBMP-2 implantation after core depression,with 12 rabbits,24 femoral head necrosis;Croup D treated with core depression group without implantation,with 12 rabbits,24 femoral head necrosis.All animals were sacrificed after 12 weeks.The ability of repairing bone defect was evaluated by X-ray radiograph.Bone mineral density analysis of the defect regions were used to evaluate the level of ossification.The morphologic change and bone formation was assessed by HE staining.The angiogenesis was evaluated by VEGF immunohistochemistry.Results:The osteogenetic ability and quality of femoral head necrosis in group B were better than those of other groups after 12 weeks by X-ray radiograph and morphologic investigation.And the angiogenesis in group B was better than other groups.Group C had similar osteogenetic quality of femoral head necrosis and angiogenesis with group D.Conclusions:The treatment of rhBMP-2/PLCA implantation after core depression can promote the repair of rabbit femoral head necrosis.It is a promising and efficient synthetic bone material to treat the femoral head necrosis.
文摘AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and sixteen patients submitted to operations associated with colorectostorny from January 2004 to September 2005 were randomized to two groups: In experimental group (n = 161), the nasogastric tube was removed after the operation from 12 to 24 hours and was promised immediately oral feeding; In control group (n = 155), the nasogastric tube was maintained until the passage of flatus per rectum. Variables assessed included the time to first passage of flatus, the time to first passage of stool, the time elapsed postoperative stay, and postoperative complications such as anastornotic leakage, acute dilation of stomach, wound infection and dehiscense, fever, pulmonary infection and pharyngolaryngitis. RESULTS: The median and average days to the first passage of flatus (3.0±0.9 vs 3.6±1.2, P〈0.001), the first passage of stool (4.1± 1.1 vs 4.8±1.4 P〈0.001) and the length of postoperative stay (8.4±3.4 vs 9.6±5.0, P〈0.05) were shorter in the experimental group than in the control group. The postoperative complications such as anastomotic leakage (1.24% vs 2.58%), acute dilation of stomach (1.86% vs 0.06%) and wound complications (2.48% vs 1.94%) were similar in the groups, but fever (3.73% vs 9.68%, P〈0.05), pulmonary infection (0.62% vs 4.52%, P〈0.05) and pharyngolaryngitis (3.11% vs 23.23%, P〈0.001) were much more in the control group than in the experimental group. CONCLUSION: The present study shows that applicationof gastrointestinal decompression after colorectostomy can not effectively reduce postoperative complications. On the contrary, it may increase the incidence rate of fever, pharyngolaryngitis and pulmonary infection. These strategies of early removing gastrointestinal decompression and early oral feeding in the patients undergoing colorectostomy are feasible and safe and associated with reduced postoperative discomfort and can accelerate the return of bowel function and improve rehabilitation.
基金Supported by the National Natural Science Foundation of China (No.81670885)the Science and Technology Program of Guangdong Province, China (No.2013B020400003)the Science and Technology Program of Guangzhou, China (No.15570001)
文摘AIM: To report the effects of intravenous high-dose glucocorticoids(iv GC) and orbital decompression(OD) surgery for treatment of sight-threatening thyroid-associated ophthalmopathy(TAO).METHODS: A retrospective review of medical records from patients with sight-threatening TAO [definite or highly suspected dysthyroid optic neuropathy(DON)] treated with iv GC(60 cases) and OD(25 cases) was conducted at the Zhongshan Ophthalmic Center between January 2001 and January 2009. Patients were initially treated with iv GC(iv GC group). If no significant improvement in visual function was obtained, they then received OD surgery(OD group). The pre-versus post-treatment efficacies of either iv GC or OD in these patients were assessed using several indices, including visual acuity, intraocular pressure, ocular alignment, ocular motility, and exophthalmos. RESULTS: Nighty-one eyes had definite DON while 79 were considered to have highly suspected DON. In the iv GC group, 51 individuals(85.0%) eventually demonstrated normal vision, while 10 patients(16.7%) demonstrated a reduction in deviation(P<0.01), and 35 cases(58.3%) showed slight improvements in ocular motility(P<0.01). In OD group, visual acuity improved in 24 cases(96.0%, P<0.01) and all patients showed varying reductions of exophthalmos(mean: 4.35±1.13 mm, P<0.01). Eight cases(32.0%) experienced an 8-15 PD reduction of deviation and ocular motility improved in 12 cases(48.0%), while 3 patients(12.0%) developed new-onset strabismus with diplopia post-surgically(P<0.01). Patients were followed up at an average of 1.55±1.07 y. CONCLUSION: Both iv GC and OD show good therapeutic efficacy in the treatment of sight-threatening TAO. Thepresence of extremely poor eyesight(≥0.5 log MAR) was corrected in some patients with iv GC alone, thus sparing these patients from subsequent OD surgery. In patients who were refractory to steroids, subsequent OD surgery often provided satisfactory outcomes, however, new-onset strabismus with diplopia was observed in 12.0% of these cases.
文摘BACKGROUND:Excessive hepatocyte apoptosis and bile lakes in severe obstructive jaundice might impair liver functions.Although decompression of the bile duct has been reported to improve liver functions in animal studies,the mechanism of obstruction differs from that in humans.This study aimed to determine the profiles of hepatocyte apoptosis and bile lakes following bile duct decompression in patients with severe obstructive jaundice in the clinical setting.METHODS:We conducted a 'before and after study' on severe obstructive jaundice patients as a model of inhibition of the excessive process by bile duct decompression.Specimens of liver biopsies were taken before and after decompression of the bile duct and then stained by terminal deoxynucleotide transferase-mediated dUTP nick end-labeling(TUNEL) to identify hepatocyte apoptosis and by hematoxilin-eosin(HE) to identify bile lakes.All measurements were independently done by 2 observers.RESULTS:Twenty-one severe obstructive jaundice patients were included.In all patients,excessive hepatocyte apoptosis and bile lakes were apparent.After decompression,the hepatocyte apoptosis index decreased from 53.1(SD 105) to 11.7(SD 13.6)(P<0.05),and the bile lakes from 23.6(SD 14.8) to 10.9(SD 6.9)(P<0.05).CONCLUSION:Bile duct decompression improves hepatocyte apoptosis and bile lakes in cases of severe obstructive jaundice,similar to the findings in animal studies.
文摘U-shaped sacral fractures are rare and often difficult to diagnose primarily due to the difficulty in obtaining adequate imaging and the severe associated injuries. These fractures are highly unstable and frequently cause neurological deficits. The majority of surgeons have limited experience in management of U-shaped sacral fractures. No standard treatment protocol for U-shaped sacral fractures has been available till now. This study aimed to examine the management of U-shaped sacral fractures and the early outcomes. Clinical data of 15 consecutive patients with U-shaped sacral fracture who were admitted to our trauma center between 2009 and 2014 were retrospectively analyzed. Demographics, fracture classification, mechanism of injury and operative treatment and deformity angle were assessed. All the patients were treated with lumbopelvic fixation or (and) sacral decompression. EQ-5d score was applied to evaluate the patients' quality of life. Of the 15 consecutive patients with U-shaped sacral fracture, the mean age was 28.8 years (range: 15-55 years) at the time of injury. There were 6 females and 9 males. The mean follow- up time was 22.7 months (range: 9-47 months) and mean full weight-bearing time was 9.9 weeks (range: 8-14 weeks). Ten patients received lumbopelvic fixation and sacral decompression, one lombosacral fixation, and 4 merely sacral decompression due to delayed diagnosis or surgery. The post-operation deformity angle (mean 27.87°, and range: 8°-90°) of the sacrum was smaller than that pre-operation (mean 35.67; range: 15-90) with no significance difference noted. At the latest follow-up, all patients obtained neurological recovery with different extents. Visual analogue score (VAS) was reduced from preoperative 7.07 (range: 5-9) to postoperetive 1.93 (range: 1-3). All patients could walk without any aid after treatment. Eight patients were able to care for themselves and undertook some daily activities. Five patients had returned to work full time. In conclusion, lumbopelvic fixation is an effective method for stabilization of U-shaped sacral fractures with fewer complications developed. Effective reduction and firm fixation are the prerequisite of early mobilization and neurological recovery. Sacral decompression effectively promotes neurological recovery even in patients with old U-shaped sacral fractures.
文摘AIM: To evaluate the long-term results of different orbital decompression techniques performed in patients with Graves' ophthalmopathy(GO).METHODS: Totally 170 cases with GO underwent orbital decompression between 1994 and 2014. Patients were divided into 4 groups as medial-inferior, mediallateral(balanced), medial-lateral-inferior, and lateral only according to the applied surgical technique. Surgical indications, regression degrees on Hertel exophthalmometer, new-onset diplopia in the primary gaze and new-onset gaze-evoked diplopia after surgery and visual acuity in cases with dysthyroid optic neuropathy(DON) were compared between different surgical techniques.RESULTS: The study included 248 eyes of 149 patients. The mean age for surgery was 42.3±13.2 y. DON was the surgical indication in 36.6% of cases, and three-wall decompression was the most preferred technique in these cases. All types of surgery significantly decrease the Hertel values(P〈0.005). Balanced medial-lateral, and only lateral wall decompression caused the lowest rate of postoperative new-onset diplopia in primary gaze. The improvement of visual acuity in patients with DON did not significantly differ between the groups(P=0.181). CONCLUSION: The study show that orbital decompression surgery has safe and effective long term results for functional and cosmetic rehabilitation of GO. It significantly reduces Hertel measurements in disfiguring proptosis and improves visual functions especially in DON cases.