Cauda equina syndrome caused by the application of DuraSeal^(TM) in a microlaminectomy surgery:A case report

BACKGROUND The management of dural tears is important.While a massive dura can be repaired with absorbable suture lines,cerebrospinal fluid leakage can be attenuated by dural sealant when an unintended tiny durotomy occurs intraoperatively.DuraSeal is often used because it can expand to seal tears.This case emphasizes the need for caution when DuraSeal is used as high expansion can cause complications following microlaminectomy.CASE SUMMARY A 77-year-old woman presented with L2/3 and L3/4 lateral recess stenosis.She underwent microlaminectomy,foraminal decompression,and disk height restoration using an IntraSPINE~? device.A tiny incident durotomy occurred intraoperatively and was sealed using DuraSeal ^(TM).However,decreased muscle power,urinary incontinence,and absence of anal reflexes were observed postoperatively.Emergent magnetic resonance imaging revealed fluid collection causing thecal sac indentation and central canal compression.Surgical exploration revealed that the gel-like DuraSeal had entrapped the hematoma and,consequently,compressed the thecal sac and nerve roots.While we removed all DuraSeal ^(TM) and exposed the nerve root,the patient’s neurological function did not recover postoperatively.CONCLUSION DuraSeal expansion must not be underestimated.Changes in neurological status require investigation for cauda equina syndrome due to expansion.

Meningioma originating from the superior petrosal vein without dural attachment:A case report

BACKGROUND Meningioma in the cerebellopontine angle(CPA)without dural attachment is extremely rare.We report a unique case of meningioma derived from the superior petrosal vein without dural attachment.CASE SUMMARY A 44-year-old right-handed woman presented with a two-month history of headache and tinnitus.Brain magnetic resonance imaging showed a well-defined contrast-enhancing lesion in the right CPA without a dural tail sign.Tumor resection was performed using a right retro sigmoid approach.A dural attachment was not seen at the tentorium or posterior surface of the petrous pyramid.The tumor was firmly adherent to the superior petrosal vein.The origin site was cauterized and resected with the preservation of the superior petrosal vein.A diagnosis of meningothelial meningioma was made.The patient’s headache and tinnitus gradually disappeared,and a recurrence was not observed five years after the surgery.CONCLUSION The rare occurrence of meningioma without dural attachment makes it difficult to determine dural attachment before surgery.The absence of dural attachment makes it easy to completely resect such tumors.Vessels related to tumors should be removed carefully,considering the possible presence of tumor stem cells in the microvessels.

Clinical characteristics and risk factors of intracranial hemorrhage after spinal surgery

BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage after spinal surgery.METHODS A retrospective cohort study was conducted from January 1,2015,to December 31,2022.Patients aged≥18 years,who had undergone spinal surgery were included.Intracranial hemorrhage patients were selected after spinal surgery during hospitalization.Based on the type of spinal surgery,patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage.The patients'pre-,intra-,and post-operative data and clinical manifestations were recorded.RESULTS A total of 24472 patients underwent spinal surgery.Six patients(3 males and 3 females,average age 71.3 years)developed intracranial hemorrhage after posterior spinal fusion procedures,with an incidence of 0.025%(6/24472).The prevailing type of intracranial hemorrhage was cerebellar hemorrhage.Two patients had a poor clinical outcome.Based on the type of surgery,30 control patients were randomly matched in 1:5 ratio.The intracranial hemorrhage group showed significant differences compared with the control group with regard to age(71.33±7.45 years vs 58.39±8.07 years,P=0.001),previous history of cerebrovascular disease(50%vs 6.7%,P=0.024),spinal dura mater injury(50%vs 3.3%,P=0.010),hospital expenses(RMB 242119.1±87610.0 vs RMB 96290.7±32029.9,P=0.009),and discharge activity daily living score(40.00±25.88 vs 75.40±18.29,P=0.019).CONCLUSION The incidence of intracranial hemorrhage after spinal surgery was extremely low,with poor clinical outcomes.Patient age,previous stroke history,and dura mater damage were possible risk factors.It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.

侧颅底骨及硬脑膜缺损修复材料组织学研究

通过手术造成狗侧颅底骨及硬脑膜大面积缺损,用阔筋膜、浅筋膜修复,交对阔膜及硬脑膜进行了拉力测试,结果显示阔筋膜单位宽度承受拉力大于硬脑膜,阀筋膜体外组织培养可以存活3个月以上,并有大量成纤维细胞生长,其修复硬脑膜缺损不是起支架作用,而是其本身成活,通过1～15周连续组织学观察,修复之阔筋膜等细胞结构正常存活,有大量毛细血管及成纤维细胞增生,阔筋膜暴露组(骨缺损直径为3.0cm×4.0cm左右)肉芽组织表面可见鳞状上皮形成,与阔筋膜连于一体,逐渐向修复中心爬行,无骨移植或植皮未见脑膜脑膨出现象。

Induced dural lymphangiogenesis facilities soluble amyloid-beta clearance from brain in a transgenic mouse model of Alzheimer's disease

Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer＇s disease.The therapeutic effect of current pharmacotherapies is unsatisfactory,and some treatments cause severe side effects.The meningeal lymphatic vessels might be a new route for amyloid-β clearance.This study investigated whether promoting dural lymphangiogenesis facilitated the clearance of amyloid-β from the brain.First,human lymphatic endothelial cells were treated with 100 ng/m L recombinant human vascular endothelial growth factor-C（rh VEGF-C） protein.Light microscopy verified that rh VEGF-C,a specific ligand for vascular endothelial growth factor receptor-3（VEGFR-3）,significantly promoted tube formation of human lymphatic endothelial cells in vitro.In an in vivo study,200 μg/m L rh VEGF-C was injected into the cisterna magna of APP/PS1 transgenic mice,once every 2 days,four times in total.Immunofluorescence staining demonstrated high levels of dural lymphangiogenesis in Alzheimer＇s disease mice.One week after rh VEGF-C administration,enzyme-linked immunosorbent assay results showed that levels of soluble amyloid-β were decreased in cerebrospinal fluid and brain.The Morris water maze test demonstrated that spatial cognition was restored.These results indicate that the upregulation of dural lymphangiogenesis facilities amyloid-β clearance from the brain of APP/PS1 mice,suggesting the potential of the VEGF-C/VEGFR-3 signaling pathway as a therapeutic target for Alzheimer＇s disease.

Combination of dura turning-over and decompressive craniectomy： a new pattern of surgery for cerebral infarction caused by craniocerebral gunshot injury

Background:Craniocerebral gunshot injury refers to a wound caused by a bullet passing through or lodged in brain tissue,resulting in the loss of function of a certain area or other fatal damage to the human brain.Craniocerebral gunshot injury is usually life-threatening and is very common in modern warfare,accounting for the majority of battle casualties.Most of the patients suffer from acute cerebral infarction caused by vascular injury.Lack of early and solid battlefield emergency medical interference adds to the risk of death among the wounded.Case presentation:We present a 24-year-old man who was shot with a shotgun from a distance of 15m in an accidental injury.Forty-seven grape shots were found on his body surface by physical examination.A computed tomography(CT)scan demonstrated large areas of low-density shadows in his right parietal lobe and right temporal lobe with the midline shifting to the left side 2 days later.Afterwards,the patient was transferred to our emergency medical center at Changzheng Hospital in Shanghai.Cranial computed tomography angiography(CTA)showed a high-density shadow in the initial part of the right middle cerebral artery.The branches after the initial part were obliterated.Prompt medical attention and decompressive craniotomy(DC)surgery contributed to the final recovery from cerebral infarction of this patient.Conclusion:Bullets can penetrate or be lodged in the brain,causing intracranial hypertension.The bullets lodged in the brain can result in stenosis and embolism of a cerebral artery,causing acute cerebral infarction.Combining dura turning-over surgery with DC surgery can not only decrease intracranial pressure,which can increase the blood supply for hypertension-induced vessel stenosis,but also help vessels outside the dura mater grow into ischemic areas of the cerebral cortex.However,this new pattern of surgery needs further support from evidence-based medicine.

Neurogenic nitric oxide facilitates the central nociceptive transmission of migraine attacks

Recent studies have shown that nitric oxide （NO） can induce migraine attacks at three possible sites of action： nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies have focused on the former two sites of action. Several experiments using exogenic NO donors have suggested that nitroglycerin may induce migraine via central mechanisms. However, few studies have investigated the source of the NO involved in the central mechanisms of migraine. The present study used a cat model of migraine to represent migraine attacks in humans. We performed immunochemical staining of successive frozen sections of the brainstem and upper cervical spinal cord, and then used c-Fos protein expression to label nerve cell activation. We observed the effects of N^ω-nitro-L-arginine methyl ester （L-NAME）, a non-selective nitric oxide synthase （NOS） inhibitor, and 7-nitroindozole （7-NI）, a selective neuronal NOS inhibitor, on c-Fos and nNOS expression, which were induced by electrical stimulation to the dura mater near the superior sagittal sinus. The results demonstrated that c-Fos or nNOS immunoreactive cells was concentrated in the superficial layers （laminae Ⅰ and Ⅱ） of the spinal nucleus of trigeminal nerve. L-NAME and 7-NI pre-treatment significantly decreased c-Fos and neurogenic NOS expression; and there was a significant linear correlation between c-Fos and NOS expression （r = 0.858 2, P 〈 0.01）. These findings suggest that neurogenic NO could facilitate migraine nociceptive transmission to second-order neurons of the trigeminal nerve. However, L-NAME and 7-NI may block the activation of neurons in the spinal nucleus of the trigeminal nerve by inhibiting NO synthesis, and thereby attenuate acute migraine attacks.

Sequential spinal and intracranial dural metastases in gastric adenocarcinoma: A case report

Dural metastasis from primary gastric adenocarcinoma has been rarely reported, and its prognosis is very poor because it frequently leads to acute subdural hematoma. Here, we describe a case with sequential spinal and cranial dural metastases from gastric adenocarcinoma without subdural hematoma. A 43-yearold woman with gastric adenocarcinoma and wellcontrolled peritoneal carcinomatosis presented with back pain, right radiating leg pain, left facial palsy, and hearing loss. Magnetic resonance imaging of the spine and brain revealed dural masses at the lumbosacral junction with invasion to the L5 and S1 nerve roots and at the skull base with invasion to the internal auditory canal. She was treated with local radiotherapy, and her pain and neurologic symptoms improved after palliative radiotherapy. This is the first reported case of dural metastases of gastric adenocarcinoma of the spine and skull base but with a relatively indolent course and without subdural hematoma.

Evidence for novel age-dependent network structures as a putative primo vascular network in the dura mater of the rat brain

With chromium-hematoxylin staining, we found evidence for the existence of novel age-dependent network structures in the dura mater of rat brains. Under stereomicroscopy, we noticed that chromium-hematoxylin-stained threadlike structures, which were barely observable in 1-weekold rats, were networked in specific areas of the brain, for example, the lateral lobes and the cerebella, in 4-week-old rats. In 7-week-old rats, those structures were found to have become larger and better networked. With phase contrast microscopy, we found that in 1-week-old rats, chromium-hematoxylin-stained granules were scattered in the same areas of the brain in which the network structures would later be observed in the 4- and 7-week-old rats. Such age-dependent network structures were examined by using optical and transmission electron microscopy, and the following results were obtained. The scattered granules fused into networks with increasing age. Cross-sections of the age-dependent network structures demonstrated heavily-stained basophilic substructures. Transmission electron microscopy revealed the basophilic substructures to be clusters with high electron densities consisting of nanosized particles. We report these data as evidence for the existence of age-dependent network structures in the dura mater, we discuss their putative functions of age-dependent network structures beyond the general concept of the dura mater as a supporting matrix.

大型水电站水工结构耐久性的设计与研究

目前我国水工结构混凝主要是采用28d强度设计,没有根据不同工况选择不同的设计标准,同时也没有对混凝土的原材料进行优选,导致水工结构耐久性较差。本文基于Dura Crete的混凝土寿命预测,从选取合适的原材料、优化设计指标合理的控制以及混凝土的用水量等方面探讨了混凝土耐久性设计要点,致力于提高大型水电站水工结构耐久性。

Intracranial localization of arachnoid granulations in rats

BACKGROUND： This paper describes histomorphologic studies on arachnoid granulations in rats, which have not been investigated in China to our knowledge. OBJECTIVE： To observe the distribution of intracranial arachnoid granulations in rats. DESIGN, TIME AND SETTING： The observational experiment was performed in the Academy of Life Sciences of Shandong Taishan Medical College from May to August 2004. MATERIALS： Thirty healthy adult Wistar rats （3-4 months old） of SPF grade, equal numbers of each sex, were selected for this study. Methylene blue parenteral solution was provided by Jiangsu Jichuan Pharmaceutical Company （China）, and an optical microscope （Type： CH20; Olympus Co. Ltd., Japan） was used for observation of the histomorphology of the arachnoid granulations. METHOD： Injection of methylene blue parenteral solution into the cerebellomedullary cistern of rats. MAIN OUTCOME MEASURE： The blue stained parts of the lateral sinus were sectioned, stained by hematoxylin and eosin, and then observed under the microscope. RESULTS： The cavitas subarachnoidealis had extensive blue staining after methylene blue injection, while the arachnoid and dura were without dye accumulation. The blue dye indicated the location of the arachnoid granulations. The location of these granulations was fixed, mainly in the lateral sinus at both sides of confluence within 4 mm of the internal jugular vein. CONCLUSION： The arachnoid granulations of the rat were located mainly in the lateral sinuses of the dura mater.

Effect of visual stimulus locations on pattern-reversal visual evoked potential An epidural electrocorticogram study

To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex （V1）, a micro-electromechanical system-based microelectrode array with nine channels was implanted on the cerebral dura mater of V1 in adult cats. 2 Hz pattern reversal checkerboard stimul were used to stimulate the four visual quadrants （i.e., upper left, upper right, lower left, and lower right fields）. The results showed that there was a N75 component of the visual evoked potential around 50-80 ms after the onset of a checkerboard stimulus, and the onset of these N75 peaks varied with different stimulus locations. The checkerboard stimuli Jnduced shorter latencJes in the contralateral V1 than in the ipsilateral V1, while the checkerboard stimulus in the upper half visual field induced shorter latencies for N75. These results suggested that the pattern-reversal stimuli induced neural activities in V1 that can be recorded with multichannel microelectrodes, and more detailed temporal and spatial properties can be measured.

Giant pseudomeningocele after spinal surgery:A case report

Very few reports have described giant pseudomeningoceles ≥ 8 cm in diameter. We report this case of the biggest giant pseudomeningocele at the unusual cervicothoracic level. A 59 year old man who underwent cervicothoracic laminectomy had a giant pseudomeningocele detected and the lesion gradually grew to about 15 cm in diameter by 2 years postoperatively. Cerebrospinal fluid leak closure was performed and the postoperative course was favorable. We present this case, review the literature and discuss the size and portion, mechanism of formation, symptoms and treatments of giant pseudomeningocele.

Adult rhabdomyosarcoma originating in the temporal muscle,invading the skull and meninges:A case report

BACKGROUND Rhabdomyosarcoma(RMS)is a rare malignant tumor of mesenchymal origin that mainly affects children.Spindle cell/sclerosing RMS(SSRMS)is even rarer.It is a new subtype that was added to the World Health Organization disease classification in 2013.To the best of our knowledge,this is the first reported case of adult SSRMS disease classification originating in the temporal muscle.CASE SUMMARY SSRMS originating in the temporal muscle of a male adult enlarged rapidly,destroyed the skull,and invaded the meninges.The tumor was completely removed,and the postoperative pathological diagnosis was SSRMS.Postoperative recovery was good and chemotherapy and radiotherapy were given after the operation.Followed up for 3 mo,no tumor recurred.CONCLUSION RMS is one of the differential diagnoses for head soft tissue tumors with shortterm enlargement and skull infiltration.Preoperative computed tomography or magnetic resonance imaging is necessary for early detection of tumor invasion of the skull and brain tissue.

Safety and biodegradability of a synthetic dural sealant patch(Liqoseal)in a porcine cranial model

Background:Liqoseal consists of a watertight layer of poly(ester)ether urethane and an adhesive layer containing polyethylene glycol-N-hydroxysuccinimide(PEG-NHS).It is designed to prevent cerebrospinal fluid(CSF)leakage after intradural surgery.This study assessed the safety and biodegradability of Liqoseal in a porcine craniotomy model.Methods:In 32 pigs a craniotomy plus durotomy was performed.In 15 pigs Liqoseal was implanted,in 11 control pigs no sealant was implanted and in 6 control pigs a control dural sealant(Duraseal or Tachosil)was implanted.The safety of Liqoseal was evaluated by clinical,MRI and histological assessment.The degradation of Liqoseal was histologically estimated.Results:Liqoseal,2 mm thick before application,did not swell and significantly was at maximum mean thickness of 2.14(±0.37)mm at one month.The foreign body reaction induced by Liqoseal,Duraseal and Tachosil were comparable.Liqoseal showed no adherence to the arachnoid layer and was completely resorbed between 6 and 12 months postoperatively.In one animal with Liqoseal,an epidural fluid collection containing CSF could not be excluded.Conclusion:Liqoseal seems to be safe for intracranial use and is biodegradable.The safety and performance in humans needs to be further assessed in clinical trials.

Physicochemical and Thermal Characterization of Dura Palm Kernel Powder as a Load for Polymers: Case of Polyvinyl Chloride

This work presents the physical and thermal characterization of the dura palm kernel powder of Cameroon for their use as fillers for polymers composites. The powders of palm kernel were obtained using a percussion grinder mill with an industrial microniser which allowed obtaining a powder less than 50 μm with an apparent density between 0,505 ≤ ρ ≤ 0,680 g/cm3 at 1.56 of relative humidity. The infrared of the powder of palm kernel shows the presence of phenols groups with a large band around 3341 cm-1, -C-H at 2917.02 cm-1 and -C-O at 1040 cm-1 as the main peaks. The polyvinyl chloride of infrared obtained shows the presence of -C-Cl, -CH2 and CH as the mains peaks. The infrared of 12.5% of palm kernel powder with polyvinyl chloride shows an increase of the CH2 and CH bonds and a decrease of the -OH bonds. Thermogravimetric analysis and differential scanning calorimetric analysis of powders, polyvinyl chloride and mixture showed that the mixing powders are intermediate between the polyvinyl chloride and palm kernel powder. The powder decreased the phase temperatures of the mixture from 98.58℃ to 95℃ for the glass transition temperature and from 515℃ to 459℃ for the crystallization temperature. The thermogravimetric curves of palm kernel powder and polyvinyl chloride have showed that these materials lose their different masses in three different phases, and the one of composite (mixture of polyvinyl chloride with 12.5% of palm kernel powder) in two different phases.

Dura Mater: Anatomy and Clinical Implication

The dura mater is of similar embryological origin to the fascial organ. It contains several fibroblasts which make the dura mater a flexible structure. Dura mater is the outermost of the three layers of meninges, a thick and rigid inelastic membrane that covers the brain and spinal cord and that is impermeable to the cerebrospinal fluid. The cranial dura mater in certain respects differs anatomically from the dura material in the spinal cord, and it is important to classify them separately. This article reviews the anatomical structure of spinal and cranial dura mater and its anatomy with muscle, fascia, bone structure and ligaments. Dura mater is a structure in the body that is connected with systemic functions.

Use of Acellular Fish Skin for Dura Repair in an Ovine Model: A Pilot Study

Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.

Intradural Disc Herniation Can Be Intra-Arachnoid or Extra-Arachnoid: 2 Case Reports with MRI Diagnosis and Non-Surgical Management

Intradural disc herniation is rare and often diagnosed during surgery. We present two patients with the disease, one with an intra-arachnoid type, the other with an extra-arachnoid location. The teaching point of those cases is that this very frequent pathology can take a variety of forms, depending on the structures that are infiltrated. The key point in correctly diagnosing the intradural disc herniation is to look at the angle between the fragment and the dura. Is it pushing it (as in the usual disc herniation), embedded in it (those with the extra-arachnoid type) or does it go through to fall into the CSF (In the intra-arachnoid type)? It could be diagnosed on MRI preoperatively. Contrary to many published cases of intradural disc herniation, the two patients could be managed non-surgically.