Hydrocephalus associated to cervical hydromyelia /syringomyelia in domestic carnivores secondary to brain inflammatory conditions: New insights on MR imaging comparing to humans and critical review of the literature Hydrocephalus associated to cervical hydro/syringomyelia in domestic carnivores
Main Article Content
Abstract
Background: Communication or anatomic continuity of the fourth ventricle outlet (FVO) with the central cervical ependymal canal (CCEC) of the spinal cord in both humans and mammals is controversial.
Aim: We hypothesize that in chronic inflammatory brain conditions (CIBC) and in early stages of age this communication can be reopened. For this purpose we have conducted a study to check the potential continuity of FVO with the CCEC of the spinal cord in small domestic carnivores presenting with obstructive hydrocephalus (OH) secondary to CIBC.
Methods: Retrospective neuroradiological evaluation of a case series involving 23 domestic carnivores with CIBC presenting with both OH and cervical hydromyelia/syringomyelia. MR images checked specifically the continuity between the FVO and the CCEC.
Results: There were 18 adult and five young domestic carnivores. Anatomical continuity between the FVO and a dilated CCEC (hydromyelia) could be demonstrated on MR imaging in all young cases but in only 16 % of adult cases.
Conclusions: This study provides additional insights into understanding the relationship between the development of hydrocephalus and hydro/syringomyelia. MRI findings support that domestic carnivores have a virtual CCEC that is connected with the FVO at birth and might disappears over the years in normal, healthy animals, thus explaining hydromyelia in early stages of age rather than syringomyelia, in hydrocephalic conditions. When this anatomical continuity is present, the hydrodynamic theory have a pivotal role in the pathogenesis of hydromyelia. If not (most adult cases) other mechanisms may be activated and lead to spinal cord syringomyelia.
Key words: CNS, inflammatory diseases; CNS, animal diseases; Hydromyelia; Syringomyelia; MR imaging, hydromyelia; MR imaging, syringomyelia; MR imaging, obstructive hydrocephalus;
Keywords:
CNS, inflammatory diseases, CNS, animal diseases, Hydromyelia, Syringomyelia, MR imaging, hydromyelia, MR imaging, syringomyelia, MR imaging, obstructive hydrocephalus
Article Details
How to Cite
MUÑOZ, Alberto; MARÍN, Pilar; MARTÍNEZ, Pilar.
Hydrocephalus associated to cervical hydromyelia /syringomyelia in domestic carnivores secondary to brain inflammatory conditions: New insights on MR imaging comparing to humans and critical review of the literature.
Medical Research Archives, [S.l.], v. 10, n. 12, dec. 2022.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/3450>. Date accessed: 27 apr. 2024.
doi: https://doi.org/10.18103/mra.v10i12.3450.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
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2. Rekate HL. A contemporary definition and classification of hydrocephalus. Semin Pediatr Neurol. 2009:16:9-15.
3. Batzdorf U. A Brief history of syringomyelia. In: Tamaki N, Batzdorf U, Nagashima T, (eds). Syringomyelia: Current Concepts in Pathogenesis and Management. Springer-Verlag, Tokyo; 2001:3-9.
4. Klekamp J, Samii M, Tatagiba M, Sepehrnia A. Syringomyelia in association with tumours of the posterior fossa. Pathophysiological considerations, based on observations on three related cases. Acta Neurochir. 1995:37:38-43. Doi: 10.1007/bf02188778
5. Camacho A, Simón R, Muñoz A, Hinojosa J, Orbea C. Siryngomyelia secondary to posthemorrhagic hydrocephalus in a preterm infant. Pediatr Neurol. 200838, 211-214. Doi: 10.1016/j.pediatrneurol.2007.10.014
6 Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell M, Wolpert C, Speer MC. Chiari I malformation redefined: clinical and radiographic findings for 364 symptomatic patients. Neurosurgery. 1999;44:1005-1017. Doi: 10.1097/00006123-199912000-00054
7. Gad KA, Yousem DM. Syringohydromyelia in Patients with Chiari I Malformation: A Retrospective Analysis. Am J of Neuroradiol. 2017;8:1833-1838. Doi: 10.3174/ajnr.a5290
8. Cerda-Gonzalez S, Olby NJ, McCullough S, Pease AP, Broadstone E, Osborne, JA. Morphology of the caudal fossa in Cavalier King Charles Spaniels. Vet Radiol Ultrasound. 2009;50:37-46.
Doi: 10.1111/j.1740-8261.2008.01487.x
9. Tani K, Taga A, Itamoyo K. Iwanaga T, Une S, Nakaichi M, Taura Y. Hydrocephalus and syringomyelia in a cat. J Vet Med Sci. 2001;3;1331-1334. Doi: 10.1292/jvms.63.1331
10. Milhorat TH, Nobandegani F, Miller JI, Rao C. Noncommunicating syringomyelia following occlusion of central canal in rats. J Neurosurg. 1993;8:274-279.
Doi: 10.3171/jns.1993.78.2.0274
11. Williams B, Bentley J. Experimental communicating syringomyelia in dogs after cisternal kaolin injection. Part I. Morphology. J Neurol Sci. 1980;48:93-107. Doi: 10.1016/0022-510x(80)90153-7
12. Du Boulay G, O'Connell J, Currie J, Bostick T, Verity P. Further investigations on pulsatile movements in the cerebrospinal fluid pathway. Acta Radiol. 1972;3:496-523. Doi: 10.1177/02841851720130p205
13. Muñoz A, Mateos I, Lorenzo V, Martínez J. MR cisternography/myelography of post-traumatic spinal CSF fistulae and meningeal lesions in small animals. Acta Radiol. 2013:54:569-575. Doi: 10.1258/ar.2012.120264
14. Rusbridge C, Carruthers H, Dube MP, Holmes M, Jeffery, ND. Syringomyelia in cavalier King Charles spaniels: the relationship between syrinx dimensions and pain. J Small Anim Pract. 2007;48:432-436. Doi: 10.1111/j.1748-5827.2007.00344.x
15. Tomsick, TA, Wang, LL, Zuccarello M, & Ringer, AJ. MRI T2-Hyperintense Signal Structures in the Cervical Spinal Cord: Anterior Median Fissure versus Central Canal in Chiari and Control—An Exploratory Pilot Analysis. Am J Neurorad. 2021;42:801-806. Doi: 10.3174/ajnr.a7046
16. Rusbridge C, Greitz D, Iskandar BJ. Syringomyelia: current concepts in pathogenesis, diagnosis, and treatment. J Vet Intern Med. 2006;20:469-479. Doi: 10.1111/j.1939-1676.2006.tb02884.x
17.Gardner WJ, Goodall RJ. The surgical treatment of Arnold-Chiari malformation in adults: an explanation of its mechanism and importance of encephalography in diagnosis J Neurosurg. 1950;7;199-206.
Doi: 10.3171/jns.1950.7.3.0199
18. Williams B. Current concepts of syringomyelia. Br J Hosp Med. 1970;4:331-342.
19. Oldfield EH, De Vroom HL, Heiss JD. Hydrodynamics of syringomyelia. In: Tamaki N, Batzdorf U, Nagashima T, editors. Syringomyelia: Current Concepts in Pathogenesis and Management. Springer-Verlag. Tokyo. 2001:75-89.
20. De Lahunta A, Glass E. Small animal spinal cord diseases. In: De Lahunta A, Glass E, Kent M. Veterinary, editors. Neuroanatomy and Clinical Neurology. Elsevier Saunders 2009;43-284.
21. Elliott NSJ, Bertramb CD, Martinc BA, Brodbelt AR. Syringomyelia: A review of the biomechanics. J Fluids Structures. 2013;40:1-24. Doi: 10.1016/j.jfluidstructs.2013.01.010
22. Greitz D, Flodmark O. Modern concepts of syringohydromyelia. Rivista de Neuroradiologia. 2004;7:360-361. Doi: 10.1177/197140090401700313
23. Josephson A, Greitz D, Klason T, Olson L, Spencer C. A spinal thecal sac constriction model supports the theory that induced pressure gradients in the cord cause edema and cyst formation. Neurosurgery. 2001;8:636-646. Doi: 10.1097/00006123-200103000-00039
24. Fischbein NJ, Dillon WP, Cobbs C, Weinstein PR. The ‘‘presyrinx’’ state. A reversible myelopathic condition that may precede syringomyelia. Am J Neurorad. 1999:20:7-20.
25. Greitz D. Cerebrospinal fluid circulation and associated intracranial dynamics. A radiologic investigation using MR imaging and radionuclide cisternography. (Thesis). Acta Radiol. 1993:34 Suppl 386:1-23.
26. Williams B. 1981. Simultaneous cerebral and spinal fluid pressure recordings. 2. Cerebrospinal dissociation with lesions at the foramen magnum. Acta Neurochir. 1981:59:123-142. Doi: 10.1007/bf01411198
27. Heiss JD, Patronas N, De Vroom HL, Shawker T, Ennis R, Kammerer W, et al. Elucidating the pathophysiology of syringomyelia. J Neurosurg. 1999;91:553-562. Doi: 10.3171/foc.1999.7.2.1
28. Greitz D, Ericson K, Flodmark O. Pathogenesis and mechanics of spinal cord cysts: A new hypothesis based on magnetic resonance studies of cerebrospinal fluid dynamics. Int J Neuroradiol. 1999;5:61-78.
29. Hupp M, Pfender, Vallotton NK, Rosner S, Friedl S, Zipser CM, et al. The Restless Spinal Cord in Degenerative Cervical Myelopathy. Am J Neurorad. 2021;2:597-609. Doi: 10.3174/ajnr.a6958
30. Eisenberg HM, McLennan JE,Welch K. Ventricular perfusion in cats with kaolin-induced hydrocephalus. J Neurosurg. 1974;41:20-28. Doi: 10.3171/jns.1974.41.1.0020
31. Faulhauer K, Donauer E. Experimental hydrocephalus and hydrosyringomyelia in the cat. Acta Neurochir. 1985;74:72-80. Doi: 10.1007/bf01413282
32. Becker DP, Wilson JS, Watson W. The spinal cord central canal: response to experimental hydrocephalus and canal occlusion. J Neurosurg. 1972;36:416-424. doi 10.3171/jns.1972.36.4.0416.
33. Rascher K, Booz KH, Donauer E, Donauer E. The filum terminale. A morphological study in the cat. Zschr Mikr Anat Forsch.1988;102:1-17.
34. Rougier A, Ménégon P. MRI evidence of membranous occlusion of the foramen of Magendie. Acta Neurochir. 2009;151:693-694. Doi: 10.1007/s00701-009-0225-5
35. Gardner WJ, Angel J. The mechanism of syringomyelia and its surgical correction. Neurosurgery. 1959; 6:131-140. Doi: 10.1093/neurosurgery/6.cn_suppl_1.131
36. Mohanty A, Biswas A, Satish S, Vollmer D. Efficacy of endoscopic third ventriculostomy in fourth ventricular outlet obstruction. Neurosurgery. 2008;63:905-914.
Doi: 10.1227/01.neu.0000333262.38548.e1
37. Greitz D. Unraveling the riddle of syringomyelia. Neurosurg Review. 2006;29: 251-264. Doi: 10.1007/s10143-006-0029-5
38. Oldfield EH, Muraszko K, Shawker TH, Patronas, N. Pathophysiology of syringomyelia associated with Chiari 1 malformation of the cerebellar tonsils: implications for diagnosis and treatment. J Neurosurg. 1994;80:3-15. Doi: 10.3171/jns.1994.80.1.0003
39. Thompson A, Madan N, Hesselink JR, Weinstein G, del Rio, AM, Haughton V. The cervical spinal canal tapers differently in patients with Chiari I with and without syringomyelia. Am J Neurorad. 2015; 37:755-758. 10.3174/ajnr.a4597
40. Williams B, 1980. On the pathogenesis of syringomyelia: A review. J R Soc Med. 1980;73:798-806.
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