The volume of true heterotopies of the spinal cord

1902 ◽  
Vol 2 (11-12) ◽  
pp. 612-630
Author(s):  
V. Methodiev

Here it is necessary to disassemble separately the doubling of the spinal cord in the normal spine and the doubling that sometimes accompanies the so-called. spinam bifidam (mainly in the lower lumbar region).

2013 ◽  
Vol 7 (2) ◽  
Author(s):  
Joshua Bailey ◽  
Kalyani Nair ◽  
Alyssa Macuk ◽  
Christopher Frank ◽  
Ankit Patel ◽  
...  

Medical simulation is a developing field used in the education of medical students, doctors, residents, and many other medical professionals. Despite emerging simulation tools, little has been done to address surgeries in congenital patients, specifically with regards to the spinal cord. The objective of this project was to design, fabricate, and functionally evaluate a medical simulator to address the challenge of teaching the spinal detethering surgical procedure to neurosurgery residents. This simulator was designed to mimic anatomical and physiological characteristics of the lower lumbar region. Pressure sensors were used to quantify the forces that were applied to the spinal cord during the surgical procedure and a LabVIEW program was developed to monitor the pressure profile. The simulator was functionally evaluated by six residents, one fellow, one doctor, and two medical students. A conclusive, quantitative method for scoring these surgeries has not yet been developed, however, the residents and medical students were able to compare their procedures with those of more experienced doctors and fellows via qualitative methods. Future developments will include incorporating quantitative scoring methods as well as noise elimination hardware into the design.


2015 ◽  
Vol 137 (7) ◽  
Author(s):  
Hossein Rouhani ◽  
Sara Mahallati ◽  
Richard Preuss ◽  
Kei Masani ◽  
Milos R. Popovic

The ranges of angular motion measured using multisegmented spinal column models are typically small, meaning that minor experimental errors can potentially affect the reliability of these measures. This study aimed to investigate the sensitivity of the 3D intersegmental angles, measured using a multisegmented spinal column model, to errors due to marker misplacement. Eleven healthy subjects performed trunk bending in five directions. Six cameras recorded the trajectory of 22 markers, representing seven spinal column segments. Misplacement error for each marker was modeled as a Gaussian function with a standard deviation of 6 mm, and constrained to a maximum value of 12 mm in each coordinate across the skin. The sensitivity of 3D intersegmental angles to these marker misplacement errors, added to the measured data, was evaluated. The errors in sagittal plane motions resulting from marker misplacement were small (RMS error less than 3.2 deg and relative error in the angular range less than 15%) during the five trunk bending direction. The errors in the frontal and transverse plane motions, induced by marker misplacement, however, were large (RMS error up to 10.2 deg and relative error in the range up to 58%), especially during trunk bending in anterior, anterior-left, and anterior-right directions, and were often comparable in size to the intersubject variability for those motions. The induced errors in the frontal and transverse plane motions tended to be the greatest at the intersegmental levels in the lower lumbar region. These observations questioned reliability of angle measures in the frontal and transverse planes particularly in the lower lumbar region during trunk bending in anterior direction, and thus did not recommend interpreting these measures for clinical evaluation and decision-making.


1994 ◽  
Vol 5 (2) ◽  
pp. 89-102 ◽  
Author(s):  
Bruce E. Pulford ◽  
Andrea R. Mihajlov ◽  
Howard O. Nornes ◽  
L. Ray Whalen

The effects of implantation of cultured adrenal medullary cells on the recovery of neurotransmitter specific reflex activity were studied in the rat spinal cord using electrophysiological testing methods. Cell suspensions of cultured neonatal adrenal medullary chromaffin (AM) cells (which produce catecholamines), or Schwann (Sc) cells (controls) were implanted into the lumbar region of the spinal cord 2 weeks after catecholamine (CA) denervation by intracisternal injection of 6-hydroxydopamine (6-OHDA). All cells were taken from 7 day neonates and cultured for 10 days in the presence of nerve growth factor (NGF). Three months after implantation, the extent of implant-associated recovery of reflex activity was determined by measuring electromyogram (EMG) activity and force associated with the long latency component of the hindlimb withdrawal reflex (which is CA modulated). After the electrophysiological testing, rats were anesthetized, and the spinal cords were rapidly removed and frozen. Spinal cords were sectioned longitudinally, and implanted cells were visualized using glyoxylic acid techniques. Labelled sections were examined to determine cell survival. Results indicate that 1) chromaffin cells survive for 3 months in the segments of the cord into which they have been implanted and 2) rats implanted with AM cells have significantly more forceful withdrawal reflexes than those that received Sc cells or received no implant after lesioning.


Author(s):  
Alexandra M. Gibson ◽  
Michael F. Rosser ◽  
Cintia R. de Oliveira ◽  
Rachel Lampe ◽  
Janice M. Pfeiff ◽  
...  

Abstract CASE DESCRIPTION A 3-year-old 31.1-kg castrated male mixed-breed dog was evaluated because of a 1- to 2-week history of paraparesis, knuckling of the hind feet, and difficulty posturing to urinate or defecate. CLINICAL FINDINGS The dog was paraparetic but weakly ambulatory with a kyphotic posture, a mildly decreased patellar reflex in the right pelvic limb, increased tone in both pelvic limbs, and marked hyperesthesia on paraspinal palpation of the lumbar region. The urinary bladder was enlarged and firm on palpation. Neuroanatomic findings were primarily consistent with localization to the T3-L3 spinal cord segments. Magenetic resonance imaging of the thoracolumbar spinal column revealed a discrete intramedullary spinal cord mass from the cranial aspect of L4 to the middle of L5. The mass was sampled by fine-needle aspiration, and on cytologic evaluation, the suspected diagnosis was an ependymoma. TREATMENT AND OUTCOME Owing to poor prognosis and limited treatment options, the owner elected euthanasia. Postmortem examination of the spinal cord and histologic findings for samples of the mass supported a likely diagnosis of ependymoma. CLINICAL RELEVANCE Ependymoma is a rare neoplasm in dogs but should be considered in young patients with evidence of a tumor in the CNS. Fine-needle aspiration of the spinal cord mass was possible in the dog of this report, and the cytologic findings provided useful diagnostic information.


2020 ◽  
Vol 39 (6) ◽  
pp. 505-509
Author(s):  
Sven Korte ◽  
Frank Runge ◽  
Magdalena M. Wozniak ◽  
Florian T. Ludwig ◽  
Daniela Smieja ◽  
...  

Intrathecal (IT) dosing (ie, injection into the subarachnoidal space at the lumbar region) is a common route of administration in cynomolgus monkey preclinical safety studies conducted for antisense oligonucleotides (ASO) that target central nervous system diseases. Herein we report on neurological signs that have been observed in 28 IT studies conducted in 1,016 cynomolgus monkeys. Neurological signs were classified into 5 groups: (1) A nonadverse transient absence of lower spinal reflexes. This observation occurred at low incidence in nontreated animals and in those that were injected artificial cerebrospinal fluid. The incidence increased in animals that were injected an ASO. Reflexes were present again at 24 hours or 48 hours after dosing. The incidence appeared to increase with dose. (2) Test-article-related adverse muscle tremor or muscle spasticity occurring during the injection procedure or immediately thereafter. In one-third of animals this finding responded to treatment with diazepam, in two-third it required euthanasia. (3) Neurological findings occurring between 30 minutes and 4 hours after dosing were characterized by any combination of ataxia, paresis, nystagmus, urinary incontinence, or muscle tremor. Those conditions either spontaneously resolved or they slowly worsened, eventually resulting in a poor general condition. (4) Neurological findings due to spinal cord injury were characterized by rapidly progressing paralysis of hind limbs. Magnetic resonance imaging revealed a focal hyperintense lesion, indicative of spinal cord necrosis. (5) Test-article-related adverse hind limb paresis or paralysis that occurred between 2 and 18 days after dosing. Those findings were rare and resulted in a poor general condition requiring euthanasia.


Author(s):  
Holger Pettersson ◽  
Derek C. F. Harwood-Nash
Keyword(s):  

2007 ◽  
Vol 98 (4) ◽  
pp. 2157-2167 ◽  
Author(s):  
Manuel Díaz-Ríos ◽  
Daniel A. Dombeck ◽  
Watt W. Webb ◽  
Ronald M. Harris-Warrick

Commissural interneurons (CINs) help to coordinate left–right alternating bursting activity during fictive locomotion in the neonatal mouse spinal cord. Serotonin (5-HT) plays an active role in the induction of fictive locomotion in the isolated spinal cord, but the cellular targets and mechanisms of its actions are relatively unknown. We investigated the possible role of serotonin in modifying dendritic calcium currents, using a combination of two-photon microscopy and patch-clamp recordings, in identified CINs in the upper lumbar region. Dendritic calcium responses to applied somatic voltage-clamp steps were measured using fluorescent calcium indicator imaging. Serotonin evoked significant reductions in voltage-dependent dendritic calcium influx in about 40% of the dendritic sites studied, with no detectable effect in the remaining sites. We also detected differential effects of serotonin in different dendritic sites of the same neuron; serotonin could decrease voltage-sensitive calcium influx at one site, with no effect at a nearby site. Voltage-clamp studies confirmed that serotonin reduces the voltage-dependent calcium current in CINs. Current-clamp experiments showed that the serotonin-evoked decreases in dendritic calcium influx were coupled with increases in neuronal excitability; we discuss possible mechanisms by which these two seemingly opposing results can be reconciled. This research demonstrates that dendritic calcium currents are targets of serotonin modulation in a group of spinal interneurons that are components of the mouse locomotor network.


1996 ◽  
Vol 09 (04) ◽  
pp. 177-178 ◽  
Author(s):  
R. Selcer ◽  
W. H. Adams ◽  
W. B. Thomas ◽  
B. E. Wilkens

SummaryThree middle-aged (6-8 years), intact male Dachshunds were admitted to the University of Tennessee Veterinary Teaching Hospital (UTVTH) with acute onset of back pain and pelvic limb paralysis.Physical examination of dog #1 revealed hyperaesthesia of the thoracolumbar spine. Superficial pain sensation was absent in the pelvic limbs, while deep pain sensation was intact. The cutaneous trunci (panniculus) reflex was absent caudal to the thoraco-lumbar region. Reflexes to the pelvic limbs were exaggerated.A myelogram showed dorsal deviation of the ventral contrast column and attenuation of the ventral and dorsal contrast columns at the T9-T10 disc space. A hemilaminectomy was performed from T9 to T10, and mineralized disc material was retrieved from the vertebral canal at T9-T10. The T9- T10 to L3-L4 disc spaces were fenestrated. Two weeks after surgery, superficial and deep pain sensation of the rearlimbs were present, but paralysis persisted. The animal was euthanatised at the owners’ request. A postmortem examination was not performed.Dog #2 displayed absent superficial pain sensation, and intact deep pain sensation of the pelvic limbs. Hyperaesthesia of the thoracolumbar region and hyperreflexia of the rear limbs were noted. Examination of the cutaneous trunci reflex was not performed. A myelogram revealed ventral extradural compression of the spinal cord at T9- T10. A T9-T10 hemilaminectomy revealed a large amount of extruded disc material, which was removed. The Tll- T12 to L4-L5 intervertebral discs were fenestrated. Forty-eight hours postoperatively, the patient regained voluntary motor function, and recovery was uneventful.Neurologic examination of dog #3 revealed absence of deep pain sensation in the pelvic limbs; duration of which was not known. Spinal radiographs and myelography revealed ventral extradural spinal cord compression at T9-T10 (Fig.). A right-sided hemilaminectomy at T9-T10 revealed a large amount of calcified disc material, ventral to the spinal cord. The T11-T12 through Ll- L2 intervertebral discs were fenestrated. Sixty days postoperatively, paralysis persisted and the dog was euthanatised. No postmortem examination was performed.Herniation of the T9-T10 intervertebral disc was diagnosed in three Dachshunds with acute paraplegia. The clinical diagnosis and surgical management of T9-T10 disc herniation are similar to that in the more common sites of disc herniation.


1916 ◽  
Vol 9 (Neurol_Sect) ◽  
pp. 83-85
Author(s):  
H. Campbell Thomson
Keyword(s):  

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