Radiologia Brasileira. Print version ISSN equina: review of the literature. Raízes nervosas redundantes da cauda equina: revisão da literatura. Imagenologia en Equinos. Public. · Hosted by Can-Horse Asesoria Veterinaria y etológica. Interested. clock. Mar 18, at AM – Mar 19, at PM. Dec 3, at AM – Dec 4, at PM UTC More than a year ago. pin. CESPO. Avenida Boyacá No A – 55, Bogotá, Colombia. Show Map.
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Imaggenologia extrusion of elongated roots usually occurs during the surgical opening of the dura mater 2,6,7,11, How to cite squina article. Redundant nerve roots in patients with degenerative lumbar spinal stenosis. Serpiginous filling defects may also be identified by myelography in the presence of dural or intradural arteriovenous malformations 17thus constituting an important differential diagnosis. Therefore the authors of the present review suggest that radiologists should look for RNR of the cauda equina at MRI and, if applicable, describe such finding in their reports.
Radiologia Brasileira – Raízes nervosas redundantes da cauda equina: revisão da literatura
Coronal MRI T2-weighted image also demonstrating dilated serpiginous vessels in the venous plexus arrow. Knotted neurinoma or plexiform neurofibroma in the cauda equina author’s transl.
The opening of the dura mater may be performed to rule out the hypothesis of arteriovenous malformation 7 or simply because surgeons have decided that such a procedure should be a part of the decompression 6, The redundant nerve root syndrome of the cauda equina. The relative length was obtained by measuring the distance from the maximum stenosis level to the most distant point where the presence of redundant imavenologia could be identified, and by dividing such obtained value by the height of the vertebral body located above the stenosis level.
The greater the relative length, the better the postoperative outcomes, a result that, at a first analysis, seems to be unexpected, leading the study authors to raise the hypothesis that such result was related to a greater accommodation capability of the longer redundant roots during flexion and extension of the spinal column, as related to effects of traction forces Redundant nerve roots of the cauda equina caused by lumbar spinal canal stenosis.
Mobile neurinoma of the cauda equina. Accepted after revision February 24, In that study, the velocity of conduction of redundant nerve roots was approximately one half the normal value and, in general, the redundant nerve roots presented eqhina action potentials temporarily dispersed as compared with the normal roots. There are articles suggesting that the pathological changes of the nerve roots imagenoloia irreversible at the moment of diagnosis and therefore neurological symptoms are less likely to improve with surgical decompression, but such concept is not a consensus.
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The literature is controversial about the implication of the presence of RNR in the indication for decompressive surgery for spinal canal stenosis. Redundancy of the nerve roots is probably the pathological result of a chronic compressive force at the level of the site of spinal canal constriction 9. The study authors have suggested that such results reflected the reduction and degeneration of the nerve dquina 8.
The prevalence of this syndrome may reach The recognition of redundant nerve roots at magnetic resonance imaging is important, particularly to avoid misdiagnosing other conditions such as intradural arteriovenous malformations. In the literature, signal intensity abnormalities nerve roots have not been reported in association with RNR of the cauda equina. Redundant nerve roots in patients with degenerative lumbar spinal stenosis. Redundant nerve roots of the cauda equina: Preoperative MRI images obtained for planning of surgical decompression.
The authors standardized the measurement of the relative length of the nerve roots on the most central sagittal image of the lumbar column. The anatomical study developed by Suzuki et al. Sagittal MRI T2-weighted image showing dilated serpiginous vessels arrow.
Most recently imaging findings of RNR of the cauda equina were also described for magnetic resonance imaging MRI All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License.
At the time, myelography was the only imaging method available to document the anatomy and pathology of nerve roots of the cauda equina in vivo. Redundant nerve roots of the cauda equina. Gulati DR, Rout D. Presence of increased signal intensity in the spinal cord substance arrowhead associated with medullary ischemia secondary to steal phenomenon.
Demyelination and axonal loss was considered as being a consequence of the continuous mechanical compression of nerve roots imagenologis to the stenosed spinal canal 8. The study authors have suggested that such results reflected the reduction and degeneration of the nerve fibers 8. They also have not found any significant difference in the electrophysiological manifestation between ventral and dorsal redundant nerve roots.
MR and myelographic findings. Redundant nerve roots in the cauda equina. A year-old woman with neurogenic claudication.
Spinal dural arteriovenous fistulas: Clinical significance of the redundant nerve roots of the cauda equina documented on magnetic resonance imaging. Thickened, elongated and tortuous or serpiginous nerve roots adjacent to a site of lumbar vertebral canal stenosis represent typical findings.
Serpentine myelographic defect caused by a redundant nerve root. In their investigation, those authors have not demonstrated any significant change in the anterior horn and in the anterolateral columns of the spinal cord.
The present paper is aimed at reviewing the histopathological, electrophysiological and imaging findings, particularly at magnetic resonance imaging, as well as the clinical meaning of this entity.
Accepted after revision February 24, The topographic distribution in observed in cases of redundant nerve roots was Such studies specifically mention an article where Verbiest has described a series of surgically confirmed cases of lumbar spinal stenosis 14 but, as the original text was evaluated, the authors of the present review concluded that Verbiest described elongated nerve roots in another series of cases about rare presentations of cauda equina compression The clinical condition of patients with RNR of the cauda equina is related to the natural history of the lumbar spinal canal stenosis.
The electrophysiological study of redundant nerve roots has demonstrated temporal dispersion of the action potential and delay of the velocity of the sensitive nervous conduction, although the difference in the velocity of sensitive nervous conduction has not been statistically significant 8. Also, there are reports on the indication of duroplasty in association with decompressive laminectomy was indicated for the relief of nerve root compression 11, RNR are typically associated with vertebral canal stenosis, and clinically the patient presents neurogenic claudication.
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At MRI, RNR are often associated with degenerative stenosis of the lumbar vertebral canal and therefore the recognition of such entity is important to avoid equivocal diagnosis and mainly false-positive results for arteriovenous malformations. The main pathological findings in patients with RNR of the cauda equina were derangement and reduction in the number of nervous imgenologia, demyelination, besides endoneural fibrosis and Schwann cells proliferation 8,9.
Spinal dural arteriovenous fistulas: However, the clinical presentation of vascular malformations is different from that of canal stenosis, and there are MRI findings that help in the differentiation imagenologiw these two conditions.