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R J Guiloff - One of the best experts on this subject based on the ideXlab platform.
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Spinal cord infarction with ipsilateral segmental neuropathic pain and flaccid paralysis a functional role for human afferent ventral root small sensory fibres
Journal of the Neurological Sciences, 2018Co-Authors: Mario Campero, R Hughes, Patricia Orellana, Jorge A Bevilacqua, R J GuiloffAbstract:Abstract This paper illustrates the cases of two patients with an acute onset of right brachial neuropathic pain, flaccid paralysis and contralateral thermal and thermal pain hypoesthesia, without posterior column impairment nor pyramidal signs below the segmental lesion. MRI showed right sided Spinal cord infarction, in the Anterior Spinal Artery territory between C1 and C5 in one patient and between C3 and C7 in the other. Contact Heat Evoked Potentials and Quantitative Thermal Sensory testing are consistent with contralateral, but not ipsilateral, spinothalamic tract involvement. Electromyographic results established ipsilateral segmental denervation and somatosensory evoked responses were consistent with dorsal column sparing. Unilateral Anterior cervical Spinal cord infarction may present with acute ipsilateral segmental neuropathic pain, lower motor neurone-type weakness, contralateral thermoanalgesia and no pyramidal signs. The ipsilateral pain provides novel evidence that in some instances, ventral roots can play a role in nociception in humans. The infarcted territory may result from occlusion of a sulcal commissural Artery or a number of more proximal vessels (including a single or duplicated Anterior Spinal Artery, vertebral arteries or feeding radicular arteries).
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po255 Anterior Spinal Artery territory infarct ipsilateral pain weakness Spinal cord infarction presenting with ipsilateral neuropathic pain and weakness a functional role for afferent ventral root sensory fibres
Journal of Neurology Neurosurgery and Psychiatry, 2017Co-Authors: Mario Campero, R Hughes, Patricia Orellana, Jorge A Bevilacqua, R J GuiloffAbstract:Introduction Infarction of the Anterior Spinal Artery territory manifests with bilateral segmental lower motor neurone weakness and, below the level of injury, pyramidal signs and loss of pain and thermal sensation. Two patients presented with neuropathic upper limb pain and flaccid paralysis ipsilateral to a unilateral infarction, no pyramidal signs and contralateral loss of thermal and pain sensation. We consider the site of vascular pathology and the mechanism of the ipsilateral pain. Methods and Results Two women, 22 and 24 year-old, had acute unilateral neuropathic pain and weakness of the right upper limb and contralateral thermoalgesic sensory loss. Denervation on the side of paralysis followed. CSF and SSEPs were normal. Thermal Sensory Analysis showed thermal hypoesthesia and hypoalgesia contralateral to the pain and motor deficit. Contact heat evoked potentials were absent or smaller from the arm contralateral to the paralysis. MRIs showed abnormal signal in right Anterior Spinal Artery territory at C1–2 to C4–5, and predominantly unilateral at C3–4 to C4–5 respectively. Discussion The territory matches the sulcal commisural Artery (SCA), a branch of the Anterior Spinal Artery (ASA).1 Double ASA and double SCA are described.2 This territory can also be affected by proximal pathology of the ASA, feeding radicular arteries3 and vertebral arteries.4 The ipsilateral pain may be attributed to ischaemia of ventral root afferent fibres; in the cat they supply cutaneous or visceral structures from the limbs or innervate the ventral root proper, or its sheath, and respond best to noxious stimuli.5,6 In humans the failure of dorsal rhizotomy to relieve neuropathic pain was attributed to ventral root unmyelinated axons,720% of ventral roots axons are unmyelinated8 and electrical stimulation of leg sensory nerves elicited small potentials in the ventral roots.9 Conclusion Unilateral Anterior cervical cord infarction can present with segmental acute ipsilateral neuropathic pain and lower motorneuron weakness, contralateral spinothalamic loss and no pyramidal signs below the infarction level. The territory affected may be that of a sulcal commissural Artery. The ipsilateral pain suggests that a subset of human afferent ventral root sensory fibres plays a functional role in pain. Funding Fondecyt (Chile) Grant N°1120339. References Weidaueret al. 2015. Thorn AK. Vascular Anatomy of the Spinal cord. Cheshireet al. 1996. Liet al. 2010. Cliftonet al. 1976. Janiget al. 1991. Coggeshallet al. 1975. Koet al. 2009. Phillipset al. 2000.
Randall B Griepp - One of the best experts on this subject based on the ideXlab platform.
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the collateral network concept a reassessment of the anatomy of Spinal cord perfusion
The Journal of Thoracic and Cardiovascular Surgery, 2011Co-Authors: Fabian A Kari, Christoph S Mueller, Daniel Silovitz, Robert M Brenner, Randall B GrieppAbstract:Objective Prevention of paraplegia after repair of thoracoabdominal aortic aneurysm requires understanding the anatomy and physiology of the Spinal cord blood supply. Recent laboratory studies and clinical observations suggest that a robust collateral network must exist to explain preservation of Spinal cord perfusion when segmental vessels are interrupted. An anatomic study was undertaken. Methods Twelve juvenile Yorkshire pigs underwent aortic cannulation and infusion of a low-viscosity acrylic resin at physiologic pressures. After curing of the resin and digestion of all organic tissue, the anatomy of the blood supply to the Spinal cord was studied grossly and with light and electron microscopy. Results All vascular structures at least 8 μm in diameter were preserved. Thoracic and lumbar segmental arteries give rise not only to the Anterior Spinal Artery but to an extensive paraspinous network feeding the erector spinae, iliopsoas, and associated muscles. The Anterior Spinal Artery, mean diameter 134 ± 20 μm, is connected at multiple points to repetitive circular epidural arteries with mean diameters of 150 ± 26 μm. The capacity of the paraspinous muscular network is 25-fold the capacity of the circular epidural arterial network and Anterior Spinal Artery combined. Extensive arterial collateralization is apparent between the intraSpinal and paraspinous networks, and within each network. Only 75% of all segmental arteries provide direct Anterior Spinal Artery–supplying branches. Conclusions The Anterior Spinal Artery is only one component of an extensive paraspinous and intraSpinal collateral vascular network. This network provides an anatomic explanation of the physiological resiliency of Spinal cord perfusion when segmental arteries are sacrificed during thoracoabdominal aortic aneurysm repair.
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the collateral network concept remodeling of the arterial collateral network after experimental segmental Artery sacrifice
The Journal of Thoracic and Cardiovascular Surgery, 2011Co-Authors: Christoph S Mueller, Fabian A Kari, Robert M Brenner, Randall B GrieppAbstract:Objective A comprehensive strategy to prevent paraplegia after open surgical or endovascular repair of thoracoabdominal aortic aneurysms requires a thorough understanding of the response of the collateral network to extensive segmental Artery sacrifice. Methods Ten Yorkshire pigs underwent perfusion with a low-viscosity acrylic resin. With the use of cardiopulmonary bypass, 2 animals each were perfused in the native state and immediately, 6 hours, 24 hours, and 5 days after sacrifice of all segmental arteries (T4–L5). After digestion of surrounding tissue, the vascular cast of the collateral network underwent analysis of arterial and arteriolar diameters and the density and spatial orientation of the vasculature using light and scanning electron microscopy. Results Within 24 hours, the diameter of the Anterior Spinal Artery had increased significantly, and within 5 days the Anterior Spinal Artery and the epidural arterial network had enlarged in diameter by 80% to 100% ( P P P = .0002), and a significant realignment of arterioles parallel to the Spinal cord had occurred ( P = .0005). Conclusions Within 5 days after segmental Artery occlusion, profound anatomic alterations in the intraSpinal and paraspinous arteries and arterioles occurred, providing the anatomic substrate for preservation of Spinal cord blood flow via collateral pathways.
Fabian A Kari - One of the best experts on this subject based on the ideXlab platform.
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the collateral network concept a reassessment of the anatomy of Spinal cord perfusion
The Journal of Thoracic and Cardiovascular Surgery, 2011Co-Authors: Fabian A Kari, Christoph S Mueller, Daniel Silovitz, Robert M Brenner, Randall B GrieppAbstract:Objective Prevention of paraplegia after repair of thoracoabdominal aortic aneurysm requires understanding the anatomy and physiology of the Spinal cord blood supply. Recent laboratory studies and clinical observations suggest that a robust collateral network must exist to explain preservation of Spinal cord perfusion when segmental vessels are interrupted. An anatomic study was undertaken. Methods Twelve juvenile Yorkshire pigs underwent aortic cannulation and infusion of a low-viscosity acrylic resin at physiologic pressures. After curing of the resin and digestion of all organic tissue, the anatomy of the blood supply to the Spinal cord was studied grossly and with light and electron microscopy. Results All vascular structures at least 8 μm in diameter were preserved. Thoracic and lumbar segmental arteries give rise not only to the Anterior Spinal Artery but to an extensive paraspinous network feeding the erector spinae, iliopsoas, and associated muscles. The Anterior Spinal Artery, mean diameter 134 ± 20 μm, is connected at multiple points to repetitive circular epidural arteries with mean diameters of 150 ± 26 μm. The capacity of the paraspinous muscular network is 25-fold the capacity of the circular epidural arterial network and Anterior Spinal Artery combined. Extensive arterial collateralization is apparent between the intraSpinal and paraspinous networks, and within each network. Only 75% of all segmental arteries provide direct Anterior Spinal Artery–supplying branches. Conclusions The Anterior Spinal Artery is only one component of an extensive paraspinous and intraSpinal collateral vascular network. This network provides an anatomic explanation of the physiological resiliency of Spinal cord perfusion when segmental arteries are sacrificed during thoracoabdominal aortic aneurysm repair.
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the collateral network concept remodeling of the arterial collateral network after experimental segmental Artery sacrifice
The Journal of Thoracic and Cardiovascular Surgery, 2011Co-Authors: Christoph S Mueller, Fabian A Kari, Robert M Brenner, Randall B GrieppAbstract:Objective A comprehensive strategy to prevent paraplegia after open surgical or endovascular repair of thoracoabdominal aortic aneurysms requires a thorough understanding of the response of the collateral network to extensive segmental Artery sacrifice. Methods Ten Yorkshire pigs underwent perfusion with a low-viscosity acrylic resin. With the use of cardiopulmonary bypass, 2 animals each were perfused in the native state and immediately, 6 hours, 24 hours, and 5 days after sacrifice of all segmental arteries (T4–L5). After digestion of surrounding tissue, the vascular cast of the collateral network underwent analysis of arterial and arteriolar diameters and the density and spatial orientation of the vasculature using light and scanning electron microscopy. Results Within 24 hours, the diameter of the Anterior Spinal Artery had increased significantly, and within 5 days the Anterior Spinal Artery and the epidural arterial network had enlarged in diameter by 80% to 100% ( P P P = .0002), and a significant realignment of arterioles parallel to the Spinal cord had occurred ( P = .0005). Conclusions Within 5 days after segmental Artery occlusion, profound anatomic alterations in the intraSpinal and paraspinous arteries and arterioles occurred, providing the anatomic substrate for preservation of Spinal cord blood flow via collateral pathways.
Mario Campero - One of the best experts on this subject based on the ideXlab platform.
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Spinal cord infarction with ipsilateral segmental neuropathic pain and flaccid paralysis a functional role for human afferent ventral root small sensory fibres
Journal of the Neurological Sciences, 2018Co-Authors: Mario Campero, R Hughes, Patricia Orellana, Jorge A Bevilacqua, R J GuiloffAbstract:Abstract This paper illustrates the cases of two patients with an acute onset of right brachial neuropathic pain, flaccid paralysis and contralateral thermal and thermal pain hypoesthesia, without posterior column impairment nor pyramidal signs below the segmental lesion. MRI showed right sided Spinal cord infarction, in the Anterior Spinal Artery territory between C1 and C5 in one patient and between C3 and C7 in the other. Contact Heat Evoked Potentials and Quantitative Thermal Sensory testing are consistent with contralateral, but not ipsilateral, spinothalamic tract involvement. Electromyographic results established ipsilateral segmental denervation and somatosensory evoked responses were consistent with dorsal column sparing. Unilateral Anterior cervical Spinal cord infarction may present with acute ipsilateral segmental neuropathic pain, lower motor neurone-type weakness, contralateral thermoanalgesia and no pyramidal signs. The ipsilateral pain provides novel evidence that in some instances, ventral roots can play a role in nociception in humans. The infarcted territory may result from occlusion of a sulcal commissural Artery or a number of more proximal vessels (including a single or duplicated Anterior Spinal Artery, vertebral arteries or feeding radicular arteries).
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po255 Anterior Spinal Artery territory infarct ipsilateral pain weakness Spinal cord infarction presenting with ipsilateral neuropathic pain and weakness a functional role for afferent ventral root sensory fibres
Journal of Neurology Neurosurgery and Psychiatry, 2017Co-Authors: Mario Campero, R Hughes, Patricia Orellana, Jorge A Bevilacqua, R J GuiloffAbstract:Introduction Infarction of the Anterior Spinal Artery territory manifests with bilateral segmental lower motor neurone weakness and, below the level of injury, pyramidal signs and loss of pain and thermal sensation. Two patients presented with neuropathic upper limb pain and flaccid paralysis ipsilateral to a unilateral infarction, no pyramidal signs and contralateral loss of thermal and pain sensation. We consider the site of vascular pathology and the mechanism of the ipsilateral pain. Methods and Results Two women, 22 and 24 year-old, had acute unilateral neuropathic pain and weakness of the right upper limb and contralateral thermoalgesic sensory loss. Denervation on the side of paralysis followed. CSF and SSEPs were normal. Thermal Sensory Analysis showed thermal hypoesthesia and hypoalgesia contralateral to the pain and motor deficit. Contact heat evoked potentials were absent or smaller from the arm contralateral to the paralysis. MRIs showed abnormal signal in right Anterior Spinal Artery territory at C1–2 to C4–5, and predominantly unilateral at C3–4 to C4–5 respectively. Discussion The territory matches the sulcal commisural Artery (SCA), a branch of the Anterior Spinal Artery (ASA).1 Double ASA and double SCA are described.2 This territory can also be affected by proximal pathology of the ASA, feeding radicular arteries3 and vertebral arteries.4 The ipsilateral pain may be attributed to ischaemia of ventral root afferent fibres; in the cat they supply cutaneous or visceral structures from the limbs or innervate the ventral root proper, or its sheath, and respond best to noxious stimuli.5,6 In humans the failure of dorsal rhizotomy to relieve neuropathic pain was attributed to ventral root unmyelinated axons,720% of ventral roots axons are unmyelinated8 and electrical stimulation of leg sensory nerves elicited small potentials in the ventral roots.9 Conclusion Unilateral Anterior cervical cord infarction can present with segmental acute ipsilateral neuropathic pain and lower motorneuron weakness, contralateral spinothalamic loss and no pyramidal signs below the infarction level. The territory affected may be that of a sulcal commissural Artery. The ipsilateral pain suggests that a subset of human afferent ventral root sensory fibres plays a functional role in pain. Funding Fondecyt (Chile) Grant N°1120339. References Weidaueret al. 2015. Thorn AK. Vascular Anatomy of the Spinal cord. Cheshireet al. 1996. Liet al. 2010. Cliftonet al. 1976. Janiget al. 1991. Coggeshallet al. 1975. Koet al. 2009. Phillipset al. 2000.
Sang Ki Chung - One of the best experts on this subject based on the ideXlab platform.
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perimedullary arteriovenous fistula of the filum terminale case report
Neurosurgery, 2010Co-Authors: Ki O Kwon, Sang Ki ChungAbstract:OBJECTIVE: Although a dural or intramedullary arteriovenous fistula involving the conus medullaris and fed by the lateral sacral Artery has been reported, a case of perimedullary fistula arising from an Artery in the filum terminale has not been described in the literature. The authors report the first case of perimedullary arteriovenous fistula located in the filum terminale. CLINICAL PRESENTATION: A 61-year-old man presented with a 10-year history of leg pain. Thoracolumbar magnetic resonance imaging scans revealed multiple perimedullary signal voids from T10 to L3. Angiography showed engorged perimedullary veins and a fistula fed by the Anterior Spinal Artery from the right ninth segmental Artery and by 2 branches of the left lateral sacral Artery. The Anterior Spinal Artery was also regarded as the Artery of the filum terminale. INTERVENTION: Transarterial embolization was performed to occlude the feeders from the left lateral sacral Artery, and an L5 total laminectomy was subsequently performed to obliterate residual fistulous material from the Artery of the filum terminale. The thickened, yellowish filum, surrounded by tortuous, engorged veins, was coagulated and resected. Postoperatively, the patient's symptoms gradually resolved and were not aggravated during long periods of walking. CONCLUSION: It must be noted that a fistula can be located in the filum terminale and can be successfully treated using multidisciplinary approaches.