Hyperalagesia with loss of temperature sensation in one side of the body due to pinpoint infarction of contralateral spinothalamic tract

1. An extracellular study of the cat medial thalamus has revealed four types of somatosensory neurons. These were located primarily in the n. parafascicularis, n. subparafascicularis, and n. centralis lateralis; none were found in the n. centrum medianum. There was no functional segregation of neurons within each nucleus or between nuclei. Each type of neuron had large and often bilateral receptive areas. No somatotopic organization of neurons was found within the medial thalamus. 2. Noxious (N) and noxious-tap (NT) neurons comprising 72% of the sample (78 of 109 total) were considered to be nociceptive. N cells responded exclusively to noxious mechanical stimulation of skin, muscle fascia, tendons, and joints, and to direct stimulation of A-delta- and C-fiber groups in cutaneous, articular, and muscle nerves. NT cells responded to noxious and tap stimulation in a differential manner and to stimulation of the entire spectrum of A- and C-fibers. N and NT cells accurately signaled the duration of noxious mechanical stimulation. Their nociceptive responses were also graded as a function of both noxious stimulus intensity and the number of activated A-delta- and C-fibers. Stimulation of A- and C-fibers evoked, respectively, an inital burst and a late burst of discharges. A brief period of inhibition intervened between the initial and late bursts of NT cells. Prolonged afterdischarge was often observed following noxious natural stimulation or stimulation of A-delta- and C-fibers. The phenomenon of discharge "windup" was observed during iterative stimulation of C-fibers. 3. Tap (T) neurons (10%) responded only to brisk but innocuous taps applied to skin or underlying tissue. These cells were driven only by activation of A-alpha- and A-beta-fibers. The response to such stimulation was seen as an initial burst of discharges followed by an inhibitory period. 4. Inhibited (I) neurons (18%) had resting discharges that were inhibited by noxious stimuli and stimulation of A-beta- and C-fiber groups. 5. The results obtained from monitoring the peripherally evoked responses of nociceptive N and NT neurons before and after selective lesions of the spinal cord strongly suggested that the spinothalamic tracts were the only spinal projections mediating A- and C-fiber input to these cells. Each spinothalamic tract apparently carried information originating from both sides of the body.

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Radiosurgery to the Spinal Dorsal Root Ganglion Induces Fibrosis and Inhibits Peripheral Glial Cell Activation While Preserving Axonal Neurotransmission

Neurosurgery ◽

10.1093/neuros/nyz310_131 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Ezequiel Goldschmidt ◽

Wendy Fellows-Mayle ◽

Ajay Niranjan ◽

John Flickinger ◽

L Dade Lunsford ◽

...

Keyword(s):

Dorsal Root Ganglion ◽

Dorsal Root ◽

Cell Activation ◽

The Body ◽

Male Rats ◽

Gasserian Ganglion ◽

Sprague Dawley ◽

Spinothalamic Tract ◽

Satellite Glial Cells ◽

Sensory Deficits

Abstract INTRODUCTION Stereotactic radiosurgery (SRS) is an effective technique to create lesions in the trigeminal nerve to treat trigeminal neuralgia. The lumbar dorsal root ganglion (DRG) contains the body of the sensory neurons responsible for pain. Therefore, SRS to the DRG might improve radiculopathic pain. This study was performed to examine the functional and structural effects of 40 or 80 Gy to the DRG in a rat model. METHODS A total of 8 Sprague Dawley male rats underwent 40 or 80 Gy single fraction SRS to the left L5 and L6 DRGs using the Leksell Gamma Knife Icon. The contralateral DRG served as controls. Animals were sacrificed after 3 mo, and the spines were harvested. Common histology was used to assess fibrosis and inflammation. DRGs were stained for Glial Fibrillar Acidic Protein (GFAP) and Neu-N as a measure of peripheral glial activation and neurogenesis respectively. The Von Frey Test was used to assess the integrity of the spinothalamic tract. Animals were evaluated for motor and sensory deficits bi-weekly. RESULTS No motor or sensory deficits resulted from SRS in any animal. Histological changes including fibrosis, edema, and vascular sclerosis were present on the treated, but not the control side and were more pronounced at the higher dose. SRS reduced the expression of GFAP without affecting the expression of Neu-N or internexin. The Von Frey Test did not show any differences between the two sides at either dose. CONCLUSION Both doses were well tolerated and provoked no deficits, neuronal lysis, or altered the function of spinothalamic axons. SRS reduced the activation of satellite glial cells, a primary mechanism for DRG mediated pain, and elicited similar changes as the ones described to the Gasserian ganglion after SRS signaling that SRS might be effective for the treatment of refractory radiculopathic pain.

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Percutaneous Computed Tomography-guided Radiofrequency Ablation of Upper Spinal Cord Pain Pathways for Cancer-Related Pain

Operative Neurosurgery ◽

10.1227/01.neu.0000317397.16089.f5 ◽

2008 ◽

Vol 62 (suppl_1) ◽

pp. ONS226-ONS234 ◽

Cited By ~ 21

Author(s):

Ahmed M. Raslan

Keyword(s):

Computed Tomography ◽

Spinal Cord ◽

Radiofrequency Ablation ◽

Pain Relief ◽

Cervical Spinal Cord ◽

The Body ◽

Cervical Region ◽

Spinothalamic Tract ◽

Upper Cervical ◽

Ablative Procedures

Abstract Objective: The author presents data to support the continued need for ablative procedures, particularly cordotomy, in the management of cancer-related pain. Methods: Fifty-one patients with cancer-related body or face pain were treated with computed tomography-guided radiofrequency ablation of the spinothalamic tract or trigeminal tract nucleus in the upper cervical region of the spinal cord. Forty-one patients underwent a unilateral cervical cordotomy, and 10 patients underwent a trigeminal tractotomy–nucleotomy. Three methods to assess patient pain were used: degree of pain relief, Visual Analog Scale, and total sleeping hours. The Karnofsky scale was used to measure the patient's level of function pre- and postprocedure. Results: After surgical intervention, patients reported initial and 6-months follow-up pain relief as 98 and 80%, respectively. Conclusion: Computed tomography-guided ablation of the upper cervical spinal cord is a safe and effective procedure to treat cancer pain involving the body or face. There remains a need for ablative procedures, in particular cordotomy, in the management of cancer-related pain.

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Evidence for segregated pain and temperature conduction within the spinothalamic tract

Journal of Neurosurgery ◽

10.3171/jns.1995.83.1.0008 ◽

1995 ◽

Vol 83 (1) ◽

pp. 8-12 ◽

Cited By ~ 17

Author(s):

Gerhard M. Friehs ◽

Oskar Schröttner ◽

Gerhard Pendl

Keyword(s):

Clinical Importance ◽

Contralateral Side ◽

Spinothalamic Tract ◽

Content Type ◽

Temperature Sensation ◽

Neurosurgical Treatment ◽

The Central Nervous System ◽

Temperature Sensations ◽

Temperature Conduction ◽

Fine Print

✓ The lateral spinothalamic tract, located in the anterolateral quadrant of the white matter of the spinal cord, is one of the most important structures in transmitting pain within the central nervous system. It has been known for almost a century that destruction of fibers in this tract results in analgesia contralateral to the lesion. The effectiveness and clinical importance of interruption of the lateral spinothalamic tract has been proven in many studies. Today cordotomies are still a useful neurosurgical treatment modality, especially when pain can no longer be sufficiently controlled by analgesic drugs. Although analgesia on the contralateral side is the desired effect, one must also expect to cause disturbance in temperature sensation when performing a cordotomy. The authors' observations showed that after a cordotomy the dermatome level of analgesia can be variable within certain limits, which is in accordance with the literature. Surprisingly, however, the loss of temperature sensation may differ significantly from the loss of pain sensation. It was also found to be possible to perform a successful cordotomy without altering the sensation of temperature at all. This indicates that pain and temperature sensations may be conducted via separate pathways. Possible mechanisms underlying this phenomenon are discussed.

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STUDIES IN TEMPERATURE SENSATION. III. THE SENSITIVITY OF THE BODY TO HEAT AND THE SPATIAL SUMMATION OF THE END ORGAN RESPONSES

Journal of Clinical Investigation ◽

10.1172/jci100879 ◽

1937 ◽

Vol 16 (4) ◽

pp. 533-540 ◽

Cited By ~ 112

Author(s):

James D. Hardy ◽

Theodore W. Oppel

Keyword(s):

Spatial Summation ◽

The Body ◽

Temperature Sensation

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Affective Touch: The Enigmatic Spinal Pathway of the C-Tactile Afferent

Neuroscience Insights ◽

10.1177/2633105520925072 ◽

2020 ◽

Vol 15 ◽

pp. 263310552092507 ◽

Cited By ~ 1

Author(s):

Andrew G Marshall ◽

Francis P McGlone

Keyword(s):

Relevant Information ◽

The Body ◽

Spinothalamic Tract ◽

Affective Touch ◽

Lamina I ◽

Perceptual Judgments ◽

Spinal Pathway ◽

Cortical Regions ◽

Unexpected Findings

C-tactile afferents are hypothesized to form a distinct peripheral channel that encodes the affective nature of touch. Prevailing views indicate they project, as with other unmyelinated afferents, in lamina I-spinothalamic pathways that relay homeostatically relevant information from the body toward cortical regions involved in interoceptive processing. However, in a recent study, we found that spinothalamic ablation in humans, while profoundly impairing the canonical spinothalamic modalities of pain, temperature, and itch, had no effect on benchmark psychophysical affective touch metrics. These novel findings appear to indicate that perceptual judgments about the affective nature of touch pleasantness do not depend on the integrity of the lamina I-spinothalamic tract. In this commentary, we further discuss the implications of these unexpected findings. Intuitively, they suggest that signaling of emotionally relevant C-tactile mediated touch occurs in an alternative ascending pathway. However, we also argue that the deficits seen following interruption of a putative C-tactile lamina I-spinothalamic relay might be barely perceptible—a feature that would underline the importance of the C-tactile afferent in neurodevelopment.

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Vagal, sympathetic and somatic sensory inputs to upper cervical (C1-C3) spinothalamic tract neurons in monkeys

Journal of Neurophysiology ◽

10.1152/jn.1996.76.4.2555 ◽

1996 ◽

Vol 76 (4) ◽

pp. 2555-2567 ◽

Cited By ~ 53

Author(s):

M. J. Chandler ◽

J. Zhang ◽

R. D. Foreman

Keyword(s):

Electrical Stimulation ◽

Vagus Nerve ◽

Dynamic Range ◽

Stellate Ganglion ◽

The Body ◽

Stimulus Strength ◽

Spinothalamic Tract ◽

Physiological Basis ◽

Afferent Fibers ◽

Stimulation Of

1. Myocardial ischemia activates vagal and sympathetic cardiac afferent fibers. The purpose of this study was to determine a neuro physiological basis for cardiac pain referred to C1-C3 somatic dermatomes. We hypothesized that afferent fibers traveling in vagal or sympathetic nerves transmit nociceptive information to C1-C3 spinothalamic tract (STT) neurons. 2. Electrical stimulation of the left stellate ganglion to excite cardiopulmonary sympathetic afferent fibers increased extracellular activity of 44 of 77 C1-C3 STT neurons examined in 33 anesthetized male monkeys (Macaca fascicularis); responses increased as stimulus strength increased. Additionally, this stimulus inhibited 5 cells, increased/decreased activity of 2 cells, and did not affect 26 cells. 3. Electrical stimulation of the left (ipsilateral) thoracic vagus nerve excited 41 of 78 C1-C3 STT neurons, inhibited 4 neurons, increased/decreased activity of 2 neurons, and did not affect 31 neurons. Responses increased with increasing stimulus strength Contralateral vagal stimulation excited 7 of 39 cells tested, inhibited 4 cells and did not affect 28 cells. 4. Effects of stimulating one or more vagal branches were examined on 22 C1-C3 STT neurons excited by input from left thoracic vagus nerve. Stimulation of the cardiac branch excited 11 of 16 cells tested; stimulation of the recurrent laryngeal nerve excited 11 of 18 cells; stimulation of vagal fibers just rostral to the diaphragm excited 8 of 19 cells. 5. Excitatory somatic receptive fields ranged from small ipsilateral fields to large, sometimes bilateral or noncontinuous fields. Many fields included the ipsilateral neck and/or inferior jaw. Thirty-nine of 74 neurons examined were wide dynamic range (WDR), 21 were high threshold (HT), 6 were low threshold (LT), and 8 did not respond to brushing or noxious pinching of somatic tissues. Most (38 of 39) WDR cells responded to stimulation of the stellate ganglion or vagal fibers, as did 18 of 21 HT cells, 3 of 6 LT cells, and 2 of 8 cells unresponsive to brush or pinch stimuli. 6. Results of this study supported the concept that vagal and/ or sympathetic afferent activation of C1-C3 STT neurons might provide a neural mechanism for referred pain that originates in the heart or other visceral organs but is perceived in the neck and jaw region. Additionally, C1-C3 STT neurons processed sensory information from widespread regions of the body.

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Computed Tomography-guided Percutaneous Cordotomy for Intractable Pain in Malignancy

Operative Neurosurgery ◽

10.1227/01.neu.0000335645.67282.03 ◽

2009 ◽

Vol 64 (suppl_1) ◽

pp. ONS187-ONS194 ◽

Cited By ~ 16

Author(s):

Yucel Kanpolat ◽

Hasan Caglar Ugur ◽

Murat Ayten ◽

Atilla Halil Elhan

Keyword(s):

Computed Tomography ◽

Success Rate ◽

The Body ◽

Karnofsky Performance Scale ◽

Intractable Pain ◽

Spinothalamic Tract ◽

Ct Guided ◽

Cancer Group ◽

Percutaneous Cordotomy ◽

Scale Scores

Abstract Objective: Pain, usually a response to tissue damage, is accepted as an unpleasant feeling generating a desire to escape from the causative stimulus. Although, in the early stages of malignant diseases, pain is seen in 5% to 10% of cases, this rate reaches nearly 90% in the terminal stage, and pain becomes a primary symptom. Cordotomy is one of the treatment choices in pain caused by malignancies localized unilaterally to the extremities as well as the thorax and the abdomen. Methods: The target of computed tomography (CT)-guided percutaneous cordotomy is the lateral spinothalamic tract located in the anterolateral region of the spinal cord at the C1–C2 level. Between 1987 and 2007, CT-guided percutaneous cordotomies were performed in 207 patients; most (193 patients) suffered from intractable pain related to malignancy. The patients” pain scores and Karnofsky Performance Scale scores were evaluated pre- and postoperatively. Results: The initial success rate of CT-guided percutaneous cordotomy was 92.5%. The success rate was higher in the malignancy group. In the cancer group, selective cordotomy (pain sensation denervated only in the painful region of the body) was achieved in 83%. In 12 cases, bilateral selective percutaneous cordotomy was successfully applied. Conclusion: In the treatment of intractable pain, CT-guided cordotomy is an option in specially selected cases with malignancy. In this study, anatomic and technical details of the procedure and the experience gained from treating 207 patients over a 20-year period are discussed.

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