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1.
Mechanical and pathophysiological aspects of acute spinal cord trauma   总被引:1,自引:0,他引:1  
Experimental spinal cord trauma is studied with the purpose of better understanding and of finding better treatments for clinically occurring spinal cord trauma. In recent years major new insights have occurred in the pathophysiology of spinal cord trauma. A large amount of research has been carried out in experimental spinal cord trauma. It has mainly focused on vascular aspects of pathophysiology and on treatment. No generally accepted, very successful therapy for clinical use has emerged from this data. In addition, quite a few therapies which have been postulated to work have not yet been tested clinically. Finally the experimental models that have been used vary tremendously and standardisation is need ed. In this standardised model the influence of variables should be clear. The main pathophysiological phenomena that occur are rupture of cell membranes and microvessels. Microvessel rupture leads to free radical formation to thrombocyte aggregation and vessel obstruction. Cell oxygenation becomes impaired and eventually cell death occurs. This can be observed especially in the spinal cord grey matter. Cell membrane rupture leads to Ca2+-influx, neurotoxic firing with glutamate release and the activation of the arachidonic acid cascade. This results in production of thromboxanes, prostaglandins and prostacyclins. These actuate thrombocyte aggregation serotonin release, vasoconstriction and oedem and lead to cell anoxia and cell death. All processes are completed within 24 hours after which regeneration takes place.  相似文献   

2.
Abstract— A technique previously devised by the author for filling the greater part of the spinal subarachnoid space with water-soluble contrast medium (Kontrast UR) has been tested for myelographic localization, of thoracic and lumbar compression of the spinal cord in the dog. The principle for the myelographic examination has been to inject the medium in the lumbar region in a sufficient dose for it to be forced beyond the compressed part of the subarachnoid space, to permit demonstration of both the posterior and anterior limit of the compression. A single injection of 20 per cent Kontrast U into the subarachnoid space in the dose generally used (0·3 ml/kg of body weight) does not seem to have any detrimental effect on the spinal cord. On the other hand, morphologic lesions of the spinal cord, presumably to be ascribed to the preparation in question, have been observed after repeated injections of contrast medium at the same examination.  相似文献   

3.
Primary lymphosarcoma of the spinal cord has been infrequently reported. This tumor was classified as intramedullary, the least common type of spinal cord tumor. The dog had rapid onset of paresis and paralysis, with no sign of spinal pain.  相似文献   

4.
A vertebral body abscess extending into the epidural space causing spinal cord compression was diagnosed in the cervical spinal cord in four lambs and the thoracic spinal cord in four lambs. The affected lambs were aged between 4 and 10 weeks and clinical signs had been present for 7-21 days before veterinary examination. Treatment with high doses of penicillin did not result in an improvement of the neurological signs and all lambs were destroyed on humane grounds. Collection and analysis of cerebrospinal fluid (CSF) revealed a significant increase in the protein concentration in lumbar compared to cisternal CSF samples. There was a neutrophilic pleocytosis in two lumbar CSF samples. In lambs aged between 4 and 10 weeks with no history of previous locomotor dysfunction, paresis of more than 1 week duration may be suggestive of a vertebral body abscess which has extended into the epidural space causing spinal cord compression. Stagnation of CSF caudal to the lesion results in an increased protein concentration in the lumbar sample.  相似文献   

5.
Spinal disease in rabbits is most often the result of trauma; however, other causes have been reported including congenital defects and degenerative spinal diseases. Diagnosis of spinal disease is based on history, physical and neurologic examination findings, and imaging. Fractures and luxations of the spine are often apparent on plain radiographs; however, myelography is used to determine if the lesion is causing spinal cord compression that may be amenable to surgical decompression. Unless intervertebral discs are mineralized, they are not visible when viewing plain radiographic images; therefore, myelography may be useful to diagnose spinal cord compression from a herniated disc. Myelography can also define lesions that do not result in a disruption of the osseous vertebral architecture such as tumors and granulomas. In rabbits, myelography is performed when the animal is under general anesthesia and in lateral recumbency. A nonionic iodinated contrast agent is injected into the subarachnoid space, usually at the level of the lumbar spine, to outline the spinal cord and identify cord compressive or disruptive lesions.  相似文献   

6.
There have been very few clinical trials evaluating therapies for naturally occurring spinal cord injury in dogs and cats. This review describes the methods suitable for evaluating the behavioural recovery of animals with spinal cord injuries, in either a clinical or a laboratory setting. A list of commonly used methods for evaluating behavioural recovery in animals is provided, both in the clinical and laboratory setting; the tests, their limitations and benefits and specific recommendations for their use are also discussed in more depth.  相似文献   

7.
Vascular myelopathies of the spinal cord have not been described in Suidae, and are a rare finding in companion animals. An 8.5-yr female African warthog (Phacochoerus africanus) presented with an acute onset of tetraparesis. Based on neurologic findings, a cervical spinal cord lesion between C7-T2 was suspected. Magnetic resonance imaging revealed severe intramedullary hemorrhage with suspected abnormal vessels in the spinal cord at the level of the seventh cervical vertebrae. The acute onset of clinical signs and rapid deterioration of neurological status precluded surgical managements. A vascular anomaly was suspected on gross pathology and histology. Immunohistochemistry identified the lesion as a spontaneous intramedullary hematoma. Spontaneous intramedullary hematomyelia should be considered as a differential for acute onset of paresis in suid species.  相似文献   

8.
Clinical and pathological studies of a neurological disorder of 3 adult Rottweiler dogs are described. Dogs developed proprioceptive losses involving the limbs, leading to progressively worsening ataxia and hypermetria. Blood and CSF fluid analyses were normal and radiographs and myelograms showed no compressive lesions of the spinal cord. At necropsy, severe demyelination of the dorsal and lateral funiculi of the cervical spinal cord was visible grossly. Microscopically there was more extensive, symmetrical involvement of the spinal cord and brain than was apparent grossly, with demyelination of white matter tracts and sparing of axons in affected areas. These changes were considered diagnostic for leucoencephalomyelopathy. This condition has not been previously reported in Australia, and is probably transmitted genetically, presumably as an autosomal recessive trait.  相似文献   

9.
Spirocerca lupi is a nematode infecting dogs in tropical and subtropical areas. Aberrant S. lupi migration to different body organs, including the spinal cord, has been documented. To date, the diagnosis of aberrant spinal cord migration was made at post-mortem examination or as an incidental finding, during spinal surgery. We describe two dogs with acute asymmetric paraparesis that were subsequently diagnosed with spinal cord spirocercosis. In magnetic resonance (MR) images of the spine, T2 hyperintense lesions were seen in the spinal cord of both dogs. The lesions appeared isointense on T1-weighted images and focal enhancement was detected after gadolinium administration. The MR imaging findings were compatible with focal inflammation, presumably along the parasite migration tract. Gross and microscopic pathologic findings confirmed the diagnosis of aberrant spinal intramedullary migration of S. lupi in one dog, and in the other dog, the clinical and imaging findings were supportive of this diagnosis.  相似文献   

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12.
A one‐month‐old Quarter Horse colt presented with progressive gait abnormalities and weakness. The foal was ataxic at presentation. Radiography identified focal endplate irregularities and lysis at C6–7. Radiographic diagnosis was discospondylitis. Computed tomographic myelography was performed immediately following euthanasia and identified an extradural compressive spinal cord lesion corresponding to the site of discospondylitis. Post mortem examination findings included abscess formation at the C6–7 intervertebral space with osteomyelitis extending into the adjacent physes and subchondral bone of caudal C6 and cranial C7. The vertebral abscess extended into the ventral spinal canal at C6–7 and was identified as the cause of extradural spinal cord compression. Salmonella sp. was cultured and isolated from purulent exudate at the intervertebral space. Computed tomographic myelography has not been previously reported for assessment of discospondylitis in horses and was successful at accurately characterising spinal cord compression in addition to osteolytic changes associated with discospondylitis.  相似文献   

13.
Current Techniques for Evaluation of Spinal Cord Injury   总被引:1,自引:0,他引:1  
Spinal cord injuries have been evaluated in the past chiefly on the basis of subjective tests. New electronic techniques are now coming into clinical use which allow objective testing of afferent and efferent conduction through long spinal cord tracts. With continued research, it is probable that diagnosis and prognosis of spinal cord injuries can be made with a high degree of confidence.  相似文献   

14.
Reason for performing study: Localisation of spinal cord compression in horses with cervical vertebral stenotic myelopathy is inexact. Vertebral canal endoscopy has been used in man to localise spinal cord lesions and has the potential to become a useful diagnostic technique in horses. Objective: To establish a surgical approach via the atlanto‐occipital space to the cervical vertebral canal in equine cadavers and describe the endoscopic anatomy of the cervical epidural and subarachnoid spaces. Methods: The cadavers of 25 mature horses were used to assess 3 surgical methods to approach the cervical vertebral canal, including 2 minimally invasive and one open technique. Once the approach had been made, a flexible videoendoscope was inserted into the epidural space (epiduroscopy) or the subarachnoid space (myeloscopy) and advanced caudally until the intervertebral space between C7 and T1 was reached. Results: The epidural and subarachnoid spaces could not be accessed reliably using the minimally invasive techniques. Furthermore, damage to the nervous tissues was a frequent complication with these procedures. The open approach allowed successful insertion of the videoendoscope into the epidural and subarachnoid spaces in all horses and no inadvertent damage was observed. Anatomical structures that could be seen in the epidural space included the dura mater, nerve roots, fat and the ventral internal vertebral venous plexus. In the subarachnoid space, the spinal cord, nerve roots, blood vessels, denticulate ligaments and external branch of the accessory nerve were seen. Conclusions: Using the open approach, epiduroscopy and myeloscopy over the entire length of the cervical vertebral canal are possible in the mature horse. Potential relevance: Cervical vertebral canal endoscopy may become a valuable tool to localise the site of spinal cord injury in horses with cervical vertebral stenotic myelopathy and could aid in the diagnosis of other diseases of the cervical spinal cord.  相似文献   

15.
Cervical spinal cord abnormalities are often unapparent on myelographic studies, because no normal values for cervical spinal cord diameter are currently available. The purpose of this study was to establish, myelographically, the normal sagittal diameter of the cervical spinal cord in large and small breed dogs and its relationship to the sagittal diameter of the vertebral canal and sagittal height/length of the corresponding vertebral bodies. Forty-one adult dogs underwent cervical radiography and myelography. Spinal cord and vertebral canal sagittal diameter, vertebral body height at C2 to 5, body length at C3 to 5, and dorsal spine length of C2 were measured on lateral views. Ratios of spinal cord:vertebral canal diameter, spinal cord:body height, and spinal cord:body length/spine were calculated, and a normal range was determined for small and large breed dogs. The spinal cord:vertebral canal ratios showed that small breeds have a higher cervical cord-to-canal ratio than large breeds. The mean values and ranges of 14 ratios are reported. The ratios of spinal cord:body length at C2 to 4 in small breeds and spinal cord:body height at C3 to 5 in large breeds were found to be the most accurate for assessing spinal cord sagittal diameter. These normal ranges would allow quantitative and objective evaluation of the cervical spinal cord by myelography and early identification of dogs with altered spinal cord diameter, which could be further evaluated by means of alternative imaging techniques.  相似文献   

16.
Current Concepts in the Management of Acute Spinal Cord Injury   总被引:3,自引:0,他引:3  
Acute injury to the spinal cord initiates a sequence of vascular, biochemical, and inflammatory events that result in the development of secondary tissue damage. Experimental studies and clinical trials in humans have demonstrated that the extent of this secondary tissue damage can be limited by pharmacologic intervention at appropriate intervals after injury. High doses of methylprednisolone sodium succinate (MPSS) improve the outcome of acute spinal cord injury in humans if treatment is initiated within 8 hours of injury. Starting therapy more than 8 hours after injury is detrimental to outcome. The clinical efficacy of methylprednisolone in improving the outcome of canine spinal cord injuries has not yet been demonstrated and its use by veterinarians is controversial. Many dogs are not seen by a veterinarian within the 8-hour window after injury, and these dogs frequently are treated with nonsteroidal anti-inflammatory drugs or large doses of dexamethasone or prednisone before methylprednisolone treatment can be initiated, thus increasing the risk of severe adverse effects. Other drugs that may provide safer and more effective alternatives to methylprednisolone include thyrotropin-releasing hormone (TRH), the 21-aminosteroids, and kappa opioid agonists. Recent studies suggest that modulation of the influx of inflammatory cells and activation of endogenous microglial cells may provide another means of improving the outcome of acute spinal cord injuries. Many drugs being developed to treat acute spinal cord injury have shown promising results when evaluated experimentally. However, any proposed therapeutic strategy should be evaluated in prospective blinded clinical trials before being adopted in clinics.  相似文献   

17.
Caudal cervical spondylomyelopathy is a common neurologic disorder of Doberman pinschers which has a number of striking similarities to cervical spondylotic myelopathy in humans. Diagnosis of this human disease is facilitated considerably by the use of computed tomographic (CT) myelography. Sixteen Doberman pinscher dogs with caudal cervical spondylomyelopathy were studied by conventional myelography followed by CT myelography. A close correlation was noted between the CT myelographic appearance of the cervical spinal cord in these dogs, and that reported for human cervical spondylotic myelopathy. Five dogs had atrophy of the spinal cord, and in another there was an accumulation of contrast medium within the spinal cord. These features are often associated with a poor response to surgical decompression in humans with cervical spondylotic myelopathy. The CT examination provided information that could not be obtained by conventional myelography alone and should be considered as an additional diagnostic procedure in dogs with caudal cervical spondylomyelopathy.  相似文献   

18.
OBJECTIVE: To analyze the morphology, cytoarchitecture, and lumbosacral spinal cord projections of the red nucleus (RN) in cattle. ANIMALS: 8 healthy Friesian male calves. PROCEDURES: Anesthetized calves underwent a dorsal laminectomy at L5. Eight bilateral injections (lateral to the midline) of the neuronal retrograde fluorescent tracer fast blue (FB) were administered into the exposed lumbosacral portion of the spinal cord. A postsurgical calf survival time of 38 to 55 days was used. Following euthanasia, the midbrain and the L5-S2 spinal cord segments were removed. Nissl's method of staining was applied on paraffin-embedded and frozen sections of the midbrain. RESULTS: The mean length of the RN from the caudal to cranial end ranged from 6,680 to 8,640 microm. The magnocellular and parvicellular components of the RN were intermixed throughout the nucleus, but the former predominate at the caudal portion of the nucleus and the latter at the cranial portion with a gradual transitional zone. The FB-labeled neurons were found along the entire craniocaudal extension of the nucleus, mainly in its ventrolateral part. The number of FB-labeled neurons was determined in 4 calves, ranging from 191 to 1,469 (mean, 465). The mean cross-sectional area of the FB-labeled neurons was approximately 1,680 microm2. CONCLUSIONS AND CLINICAL RELEVANCE: In cattle, small, medium, and large RN neurons, located along the entire craniocaudal extension of the RN, contribute to the rubrospinal tract reaching the L6-S1 spinal cord segments. Thus, in cattle, as has been shown in cats, the RN parvicellular population also projects to the spinal cord.  相似文献   

19.
Intervertebral disk extrusions into the spinal cord are rarely reported in veterinary medicine, and only necropsy findings are described in previous reports. It is hypothesized that a disk lesion results in forceful injection of disk material into the spinal cord. In the 3-year-old Miniature Doberman Pinscher of our report, acute clinical signs and results of magnetic resonance imaging were consistent with this disease and helped determine the extent and character of the lesions. Alteration in the appearance of the nucleus pulposus was important in determining that intervertebral disk disease may have been present in this dog. However, a definitive diagnosis of intramedullary disk extrusion can be made only via histologic examination of a biopsy specimen or at necropsy. The dog improved substantially after surgical decompression of the spinal cord, and histologic findings in a biopsy specimen of material found within the spinal cord were consistent with mature degenerate intervertebral disk material.  相似文献   

20.
Localized diseases of the bovine brain and spinal cord   总被引:1,自引:0,他引:1  
Localized lesions of the central nervous system do occur in cattle. Those affecting the cranial nerves and focal lesions of the spinal cord are most easily recognized by careful neurologic examination. Once the lesion has been anatomically localized, likely etiologic causes can be pursued. Probably the most common cause of cranial nerve deficits in cattle is listeriosis. Important differential diagnoses include brain and pituitary abscesses and extensions of ear infections. Other possible causes include PEM, TEME, hypovitaminosis A, and several rare, sporadic causes. In young cattle, spinal trauma and vertebral body abscesses are the most common causes of progressive paresis resulting from spinal cord lesions. Congenital abnormalities must be considered in the differential diagnoses for very young calves. Non-neurologic conditions, including fractures of the limbs and especially nutritional muscular dystrophy, must be ruled out. In older cattle, compressive neoplasms, most notably lymphosarcoma, are primarily responsible for progressive paresis. Differential diagnosis should include other neurologic conditions such as delayed organophosphate neurotoxicity; early progressive diffuse neurologic diseases such as rabies, pseudorabies, and botulism; plant toxicities; and non-neurologic conditions resulting in recumbency, such as hypocalcemia and musculoskeletal trauma.  相似文献   

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