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Two cases of malignant fibrous histiocytoma in which paraplegia was a major feature are presented. The histological features of the tumours are discussed with particular emphasis on the neural involvement. A brief review of the literature on the subject is included.
Two cases of lumbosacral root cysts of different etiology are reported. Their specific radiographic features are described using the combined technique of metrizamide myelography followed by computerized tomography of the spine. The terminology of intraspinal cysts is reviewed and their distinguishing features discussed.
The morphologic changes in denervation atrophy of paravertebral muscles after severance of the posterior rami in cats were investigated, using histochemical methods and electromyography. Using a paraspinal approach, three branches of the posterior rami on the left side were cut under microscopy at one, two, or three levels (L2 approximately L4). Muscle atrophy was evaluated, using the percent wet weight and the percent diameter of muscle fibers as parameters. Myosine ATPase stain was used to observe reinnervation. Four weeks after surgery, the range and severity of muscle atrophy increased proportionally to the number of posterior rami severed. Muscle atrophy was revealed at one or two levels caudal to the injured nerve level. At 12 and 24 weeks, muscle atrophy recovered gradually. In more than two-level injury groups, however, recovery of percent wet weight reached up to 80% even after 24 weeks, despite the fact of reinnervation demonstrated in some parts of the denervated muscles.
Ketamine, an analgesic-cataleptic drug, provides pain relief without respiratory depression. Ketamine with the preservative benzethonium chloride 0.1 mg/ml was injected intrathecally into 4 baboons under Ketamine anaesthesia. A control group of 2 baboons received intrathecal saline. No assessment as to relief from experimental pain was possible, but all the baboons recovered normally from anaesthesia and were found moving about in their enclosures without gross evidence of neurological impairment. No adverse reactions were noted. One month after the intrathecal injection the baboons were sacrificed, and an autopsy was performed within 30 minutes. No macroscopic abnormally of the cord was noticed. Microscopic examination revealed oedema of a few nerve roots in all animals irrespective of whether ketamine or saline had been injected intrathecally. No other changes attributable to ketamine were seen, and its is therefore concluded that, in the doses given, intrathecally injected ketamine would seem to be safe.
In radicular disturbances not only the autonomous reflexes of the appertaining muscles may be weakened or extinguished, but those of the antagonists may also be accentuated. In case of an L4 or an L5 syndrome the observation of these signs may give additional differential-diagnostic criteria.
STUDY DESIGN: To analyze the effects of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma on cauda equina function and to define if any of these cytokines could induce nerve root dysfunction comparable with the situation with application of nucleus pulposus. SUMMARY OF BACKGROUND DATA: Proinflammatory cytokines derived from the intervertebral disc have been suggested to mediate the nucleus pulposus-induced nerve root injury following local application of nucleus pulposus. However, it is not known if such cytokines may induce similar injury if applied separately. METHODS: A total of 29 pigs were used. Nucleus pulposus was harvested from lumbar discs and applied to the sacrococcygeal cauda equina following laminectomy of the first coccygeal vertebra in seven pigs. Five pigs received 1.66 microg of tumor necrosis factor-alpha, five pigs received 0.85 microg of interleukin-1beta, and five pigs received 1.66 microg of interferon-gamma. Seven pigs received autologous fat for control. Nerve conduction velocity was studied by local electrical stimulation and recordings in the tail muscles 7 days after the application. RESULTS: Application of nucleus pulposus and fat induced similar effects as seen in previous studies, with normal nerve conduction velocity for fat and a significant reduction for nucleus pulposus. Application of both interleukin-1beta and IFN-gamma induced slight reductions of nerve conduction velocity compared with fat, but they were not statistically significant. Tumor necrosis factor-alpha, however, induced a reduction of the velocity that was even more pronounced than for nucleus pulposus. CONCLUSION: Based on previous observations and the data of the present study, one may conclude that tumor necrosis factor-alpha from nucleus pulposus cells seems to be intimately involved with the basic pathophysiologic events leading to both nerve root dysfunction and pain after local, epidural application of nucleus pulposus. One may therefore also suspect that pharmacologic inhibition of tumor necrosis factor-alpha may at least theoretically be considered in the clinical situation with disc herniation and sciatica.
This study consists of 3 sections: a descriptive study of the intervertebral foramen by dissection, supplemented by millimetric sections made with the cine-microabrasive apparatus (patented) on 12 specimens frozen with liquid nitrogen; a study of the attachments of the roots made during manipulations testing the resistance to avulsion of the rootlets, the roots, the dural sheath and the fibrous expansions at the periphery of the intervertebral foramen; and a study of the mobility of the roots in the foramina during movements effected within and outside the spine. We concluded that the classical description of an intervertebral foramen as occluded by a taut membrane like a drum-head is false as only perforated expansions attach the root to the foramen. Further, the points for attachment of the roots are the dura mater and the fibrous expansion passing from the foramen to the sheath of the spinal n. Finally, from the aspect of mobility, there are 2 distinct compartments and movements in one are not perceived in the other compartment if the attachments are unbroken. These attachments are a barrier interposed between the two compartments.
The authors present percutaneous technic treatment of some pain syndrom by thermocoagulation of rachidian nerves with radiofrequency generator. This method had been employed on 60 patients in various indications (cervico-occipital neuralgias, low back pain, stage syndrom, painful scar etc...). After anatomic justification one literature analysis precede personal results of this therapeutic method. This one is easy to realise and seems to deserve a good place in the actual possibility of functional neurosurgery.
Proteome analysis was carried out to identify the proteins associated with neuropathic pain after peripheral nerve injury. Five proteins displayed different expression levels among three groups of rats. Among these proteins, creatine kinase B expression level was lower in the pain-positive rats compared to the sham or pain-negative rats. Therefore, a lower creatine kinase B expression level may be important in the development and maintenance of neuropathic pain.
Studies have been made on total impulse activity in the skin nerves of the frog during application of acid solutions as well as during tactile stimulation. It was shown that the reactions to various stimuli differ with respect to their pattern and amplitude of integrated response curve which reflects changes in the frequency of total impulsation. In responses to test solutions and tactile stimulation, different units may be involved which specifically react to each of the stimuli. This specificity of single elements is also revealed during changes in the evoked total activity resulting from superficial skin anaesthesia. Possible nature of peripheral structures involved in these reactions is discussed.
Formation of glial bundles in the proximal portion of the ventral nerve roots is described in a 51-year-old patient with the sporadic form of amyotrophic lateral sclerosis (ALS). Although the bundles were relatively fewer, they were identical in morphology and distribution to those consistently found in Werdnig-Hoffmann disease (WHD). The occurrence of glial bundles in ALS, albeit rare, indicates that this phenomenon is not a unique feature of WHD. Similar changes have been observed in several other unrelated conditions, always in association with degeneration of neurons or axons. Thus, outgrowth of astrocytes in the form of glial bundles should be considered a special type of astrocytic reaction at the interface of the central and peripheral nervous systems.
A 46-year-old woman suffered a meningococcal meningitis followed by a rapidly progressive lumbosacral pluriradicular syndrome. Myelography showed multiple nodules on the lumbar radices. A biopsy showed tissue with numerous Verocay-like bodies, spindle shaped and lymphocytoid cells which was diagnosed as schwannoma. There was a small group of polygonal cells with somewhat irregular and hyperchromatic nuclei. Postoperatively, she developed intracranial hypertension and died. CT scan and MRI revealed multiple occipital lesions consistent with metastases. At autopsy the cauda equina showed multiple nodular lesions with morphology comparable to the biopsy. However, pigment producing cells were also present. There were metastases with distinct morphological features in the brain, myocardium, thyroid gland and pancreas. Some consisted of pigmented, large, pleomorphic cells, others of non-pigmented, spindle-shaped and less pleomorphic cells. In this case, the diagnosis of metastasizing pigmented schwannoma is the most plausible hypothesis.
The aim of this study was to determine the urodynamic effects of sacral (S3) nerve stimulation in patients with urge incontinence due to detrusor overactivity which has been refractory to conservative treatment. A total of 24 patients with idiopathic detrusor instability and five with neurogenic hyperreflexia were studied urodynamically before and 6 months after a permanent S3 foramen electrode implant. The urodynamic studies at follow-up were done with the stimulus on. Clinically, the average voiding frequency, the number of leakage episodes and pad use per 24 h decreased significantly. Improvement in several urodynamic parameters was noted. In the idiopathic as well as in the neurogenic group, the correlation between symptomatic and urodynamic improvement was incomplete. Neuromodulation leads to improvement of several urodynamic parameters in patients with urge incontinence due to detrusor overactivity which has been refractory to conservative treatment and appears to be a valuable treatment option in these patients.
A case of primitive neuroectodermal tumor arising in the cervical nerve root of a 28-year-old man is presented. Histologically, the tumor was characterised by proliferation of primitive neuroectodermal cells and formation of numerous Homer-Wright type rosettes. A cell line (Nagai line) was established from the tumor. Electron microscopic examination of Nagai cells revealed numerous microrosette formation with microvilli-like cytoplasmic processes projecting into the central lumina. Neurosecretory granules appeared in the cytoplasmic processes when Nagai cells were treated with dibutyryl cyclic AMP. Primitive satellite cells which completely surrounded other tumor cells with their tongue-like slender cytoplasmic processes were also found. Histogenesis of this unique tumor was discussed comparing with the neuroblastoma of sympathetic nervous system, medulloblastoma of the central nervous system, and with the tumors induced by Adenovirus type 12 in animals. It was concluded that the tumor was neuroepithelioma derived from a primitive stem cell of neural crest origin which possesses the bipotency to differentiate toward either neuroblastic or neurilemmal line.
Contrastographic techniques with intrathecal injections (SRG, Myelo-CT) are widely employed in the diagnostic approach to lumbar pathologic conditions. These techniques allow pathologic changes to be demonstrated and the information they yield helps plan the correct surgical approach. However, these invasive examinations are seldom employed for the high incidence of side-effects. The latter are related to various causes, the identification of which can help reduce the side-effects themselves. The authors analyzed a study population of 522 patients subjected to radiculography, using needles of different gauges (18-23 G), and injected non-ionic contrast medium in doses ranging 5-10 ml. The incidence of side-effects was significantly higher in the patients suffering from usual headache (79/237 = 33%), in those under 40 (87/238 = 37%), and in female patients (86/221 = 39%). The incidence of side-effects was lower with fine needles (41/139 = 17%) and contrast medium in doses less than 8 ml (80/337 = 24%). The patients were divided into 4 subgroups according to the different doses of contrast medium administered and to needle gauges: the above parameters exhibited a percentage decrease (21/161 = 14%) with 21-23 G needles and 8 ml of contrast medium. The authors believe it possible to reduce side-effects by using fine needles and smaller doses of contrast medium.
OBJECTIVE: To investigate the central loop of H reflex in the S1 nerve and the constitutional influencing factors in normal healthy individuals. MATERIALS AND METHODS: The study was performed on 39 apparently healthy volunteers. To obtain central H-reflex, the cathode electrode was inserted at a point 1 cm medial to the posterior superior iliac spine, perpendicular to the frontal plane. After the needle touched the sacrum, it was slightly retracted to avoid direct contract to the sacrum. The anode electrode was placed over the anterior iliac spine. The active pick-up electrode was placed at the middle of the line connecting the popliteal crease to the medial malleolus. The reference electrode was placed 2 cm distal to it. The ground eletrode was placed near the active pick-up electrode over the calf muscles. RESULTS: Mean +/- SD for minimum necessary stimulation to obtain central H-reflex was 23 +/- 13 mA. This was significantly higher than the minimum necessary stimulation to obtain peripheral H reflex (p < 0.0001 using paired t test). Mean central loop of H reflex was 6.9 msec with SD of 0.4 msec. There were no significant differences between the two sides. Mean amplitude of M-wave was 2.2 mV with SD of 1.5 in central loop study. Mean amplitude of H-wave was 2.4 mV with SD of 1.5 in central loop study. The Mean time interval between the onset of M-wave and the end of H-wave (M-H duration) was 18.5 msec with SD of 2.3. After stepwise reduction of variables, considering the correlation between leg length and other variables, the leg length was the only variable strongly correlating with central loop of H-reflex. CONCLUSION: Lack of major influencing factors after correction for leg length, elimination of a major fraction of the afferent segment of the loop, and its ability to differentiate peripheral from central lesions make central H-reflex studies an invaluable diagnostic tool.
Vascular perfusion and neuropathologic evaluation of the lumbar spinal roots and dorsal root ganglia (DRG) were studied in rats with longstanding (duration 12-15 months) streptozotocin-induced diabetes and age- and sex-matched control rats. We also undertook nerve conduction studies including F-wave recordings and measured blood flow in sciatic nerve, DRG, and superior cervical ganglion (SCG). Light microscopically, changes of the myelin sheath in the dorsal and ventral roots and vacuolated cells in the DRG were the major findings, being significantly higher in diabetic rats than in control rats. The effects of the diabetic state on myelin splitting were greater in the dorsal than ventral roots. Electron microscopic studies revealed a gradation of changes in myelin from mild separation to severe ballooning of myelin with relative axonal sparing. DRG cells showed vacuoles of all sizes with cristae-like residues, suggestive of mitochondria. These findings suggest that diabetes mellitus has a dual effect: it accelerates the normal age-related degenerative changes in the spinal roots and DRG, and it also has a selective effect on the sensory neuron. Nerve conduction studies showed markedly reduced conduction velocities in the distal nerve segments and prolonged F-wave latency and proximal conduction time despite the shorter conduction pathway in diabetic rats. Blood flow, which was measured using iodo[14C]antipyrine autoradiography, was significantly reduced in the sciatic nerves, DRG, and SCG of diabetic rats. We suggest that the combination of hyperglycemia and ischemia results in oxidative-stress and a predominantly sensory neuropathy.
65 patients with nerve root compression syndrome were examined using a new type of MR-technique, which is comparable to the conventional X-ray myelography. The results of the prospective case study were compared with previous clinical experiences (1). For the examinations a 1.0T whole body MR-system (Siemens Magnetom Impact) was used. A strong T2*-weighted 3D-FISP sequence (TR = 73 ms, TE = 21 ms, alpha = 7 degrees) was applied in sagittal orientation using a circularly polarized oval spine coil. To obtain fat suppression a frequency selective 1-3-3-1 prepulse was applied prior to the imaging sequence. The acquired 3D-data set was evaluated using a Maximum Intensity Projection (MIP) program. Our results confirmed earlier experiences which showed that the diagnostic sensitivity of 3D-MR myelography (3D-MRM) is comparable to that of conventional X-ray myelography. In cases of severe spinal canal stenosis and spondylolisthesises, and in cases of postoperative scar tissue with nerve root compressions, the sensitivity of the 3D-MRM is higher as compared to that of conventional X-ray myelography.