Structural and Functional Grey and White Matter Changes in Patients With Pain Disorders

Study Overview
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Brief Summary
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The goal of this observational study is to examine the association between exact lesion location and presence of thalamic CPSP (Central post-stroke pain) in a larger number of patients after thalamic stroke.

Detailed Description
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The researchers will explore how the brain areas and mechanisms of brain plasticity are involved in the generation of thalamic CPSP, compared to other pain disorders, using structural and functional magnetic resonance imaging (MRI) at 3 Tesla. The functional magnetic resonance imaging (fMRI) will be also used to assess the cerebral processing of heat/cold stimuli in patients with thalamic pain compared to thalamic stroke patients without pain, to patients with migraine (other central pain disorder) and to normal controls. In addition the researchers want to assess the somatosensory profile of thalamic pain patients and compare it with thalamic stroke patients without pain, patients with migraine (pain control) and normal controls.

Official Title
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Structural and Functional Grey and White Matter Changes in Patients With Pain Disorders

Conditions
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Central Post-stroke Pain

Intervention / Treatment
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* Diagnostic Test: Quantitative sensory testing (QST)
* Diagnostic Test: Magnetic resonance imaging (MRI)
* Other: Clinical interview/exam
* Other: Follow-up interview


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with thalamic central post-stroke pain (CPSP) : Patients fulfilling all of the following inclusion criteria are eligible for the study: Informed Consent as documented by signature (Appendix Informed Consent Form) History of thalamic stroke (infarction or bleed) Diagnosis of definite central-post stroke pain (according to the criteria proposed by Klit et al, 2009) No other chronic pain condition Age: ≥18 years old Patients with thalamic stroke without CPSP: Patients fulfilling all of the following inclusion criteria are eligible for the study: Informed Consent as documented by signature (Appendix Informed Consent Form) History of thalamic stroke (infarction or bleed), at least 2 years ago No chronic pain condition (neither CPSP or other pain condition) Age ≥18 years old Patients with migraine (other pain condition): Patients fulfilling all of the following inclusion criteria are eligible for the study: Informed Consent as documented by signature (Appendix Informed Consent Form) History of highly frequent (≥8 monthly migraine days) or chronic migraine (≥15 monthly migraine days). No history of stroke Age ≥18 years old Healthy controls: Participants fulfilling all of the following inclusion criteria are eligible for the study: Informed Consent as documented by signature (Appendix Informed Consent Form) No history of stroke No chronic pain condition Age: ≥18 years old Exclusion Criteria: History of severe neurological, internistic or psychiatric disease MRI related exclusion criteria: paramagnetic and/or superparamagnetic foreign objects in the body (especially when located close to the brain) Pacemaker Claustrophobia Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with thalamic CPSP (central post-stroke pain)<br>Patients with CPSP of thalamic origin due to stroke. | Diagnostic Test: Quantitative sensory testing (QST)<br>* The QST is a standardized, internationally accepted test battery consisting of several well-established, non-invasive tests, measuring parameters, which reflect nearly all aspects of somatosensation. Thermal detection threshold for the perception of cold, warm and paradoxical heat sensations Thermal pain threshold Mechanical detection thresholds for touch Mechanical pain threshold for pinprick stimuli Stimulus-response functions Wind- up ratio: The wind- up ratio represents the quotient of the pain intensity evoked by 10 pin-prick stimuli and the pain intensity evoked by one single pin-prick stimulus Vibration detection threshold Pressure pain threshold<br>Diagnostic Test: Magnetic resonance imaging (MRI)<br>* Functional and structural MRI data will be collected using a 3 Tesla Siemens Scanner with a multi-channel head coil. For the resting state functional MRI the subjects will merely lie in the scanner for about 10 minutes. A painful heat/cold stimulation will be performed to study the differences in pain processing between the three groups<br>Other: Clinical interview/exam<br>* The pain characteristics will be assessed through a standardized questionnaire. The german pain questionnaire is a validated questionnaire that assesses various dimensions of pain. Patients will also get a complete neurological examination by an experienced clinician.<br>Other: Follow-up interview<br>* Structured telephone interview with 3 Questionnaires The german pain questionnaire Questionnaire regarding clinical development since the last visit designed by the investigators German translation of 12-item-allodynia symptom checklist (ASC-12)<br>|
| Patients with thalamic stroke without CPSP<br>Patients with thalamic stroke at least 2 years ago, but without CPSP or other chronic pain disorders | Diagnostic Test: Quantitative sensory testing (QST)<br>* The QST is a standardized, internationally accepted test battery consisting of several well-established, non-invasive tests, measuring parameters, which reflect nearly all aspects of somatosensation. Thermal detection threshold for the perception of cold, warm and paradoxical heat sensations Thermal pain threshold Mechanical detection thresholds for touch Mechanical pain threshold for pinprick stimuli Stimulus-response functions Wind- up ratio: The wind- up ratio represents the quotient of the pain intensity evoked by 10 pin-prick stimuli and the pain intensity evoked by one single pin-prick stimulus Vibration detection threshold Pressure pain threshold<br>Diagnostic Test: Magnetic resonance imaging (MRI)<br>* Functional and structural MRI data will be collected using a 3 Tesla Siemens Scanner with a multi-channel head coil. For the resting state functional MRI the subjects will merely lie in the scanner for about 10 minutes. A painful heat/cold stimulation will be performed to study the differences in pain processing between the three groups<br>Other: Clinical interview/exam<br>* The pain characteristics will be assessed through a standardized questionnaire. The german pain questionnaire is a validated questionnaire that assesses various dimensions of pain. Patients will also get a complete neurological examination by an experienced clinician.<br>Other: Follow-up interview<br>* Structured telephone interview with 3 Questionnaires The german pain questionnaire Questionnaire regarding clinical development since the last visit designed by the investigators German translation of 12-item-allodynia symptom checklist (ASC-12)<br>|
| Patients with migraine<br>Patients with migraine (other central pain disorder) | Diagnostic Test: Quantitative sensory testing (QST)<br>* The QST is a standardized, internationally accepted test battery consisting of several well-established, non-invasive tests, measuring parameters, which reflect nearly all aspects of somatosensation. Thermal detection threshold for the perception of cold, warm and paradoxical heat sensations Thermal pain threshold Mechanical detection thresholds for touch Mechanical pain threshold for pinprick stimuli Stimulus-response functions Wind- up ratio: The wind- up ratio represents the quotient of the pain intensity evoked by 10 pin-prick stimuli and the pain intensity evoked by one single pin-prick stimulus Vibration detection threshold Pressure pain threshold<br>Diagnostic Test: Magnetic resonance imaging (MRI)<br>* Functional and structural MRI data will be collected using a 3 Tesla Siemens Scanner with a multi-channel head coil. For the resting state functional MRI the subjects will merely lie in the scanner for about 10 minutes. A painful heat/cold stimulation will be performed to study the differences in pain processing between the three groups<br>Other: Clinical interview/exam<br>* The pain characteristics will be assessed through a standardized questionnaire. The german pain questionnaire is a validated questionnaire that assesses various dimensions of pain. Patients will also get a complete neurological examination by an experienced clinician.<br>|
| Healthy controls<br>Age- and gender-matched healthy control subjects | Diagnostic Test: Quantitative sensory testing (QST)<br>* The QST is a standardized, internationally accepted test battery consisting of several well-established, non-invasive tests, measuring parameters, which reflect nearly all aspects of somatosensation. Thermal detection threshold for the perception of cold, warm and paradoxical heat sensations Thermal pain threshold Mechanical detection thresholds for touch Mechanical pain threshold for pinprick stimuli Stimulus-response functions Wind- up ratio: The wind- up ratio represents the quotient of the pain intensity evoked by 10 pin-prick stimuli and the pain intensity evoked by one single pin-prick stimulus Vibration detection threshold Pressure pain threshold<br>Diagnostic Test: Magnetic resonance imaging (MRI)<br>* Functional and structural MRI data will be collected using a 3 Tesla Siemens Scanner with a multi-channel head coil. For the resting state functional MRI the subjects will merely lie in the scanner for about 10 minutes. A painful heat/cold stimulation will be performed to study the differences in pain processing between the three groups<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The exact lesion location in the thalamus in patients with thalamic pain compared to patients with thalamic stroke without pain | To determine the mutual lesion location in patients with CPSP of thalamic origin in standard stereotactic space using high-resolution 3 T MRI data and to calculate odds ratio maps for the risk of developing CPSP of thalamic origin with lesion of specific areas of the thalamus. | One time assessment with a duration of max. 90 minutes. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Structural gray matter changes in patients with thalamic pain compared to the other patient groups and the healthy controls | The 3 dimensional MPRAGE images will be used to assess cortical thickness and subcortical morphometry | One time assessment with a duration of max. 90 minutes. | 
| Structural white matter changes in patients with thalamic pain compared to the other patient groups and the healthy controls | Diffusion Tensor Imaging (DTI) will be used to asess the integrity of the white matter | One time assessment with a duration of max. 90 minutes. | 
| Functional brain changes regarding the connectivity of pain networks in patients with thalamic pain compared to the other patient groups and the healthy controls | Resting state fMRI (functional MRI) will be used to assess the functional connectivity between the thalamus and cortical areas next to the default-mode network and the sensory-motor network. | One time assessment with a duration of max. 90 minutes. | 
| Functional brain changes regarding the central processing of heat/cold stimulation in patients with thalamic pain compared to the other patient groups and the healthy controls | Painful heat- and cold stimulation will be performed during the fMRI session at one time-point to assess the central processing of pain in all participants | One time assessment with a duration of max. 90 minutes. | 
| Somatosensory profile of patients with thalamic pain vs. migraine (pain-control-group) | Somatosensory profile will be assessed by quantitative sensory testing (QST). This standardized, internationally accepted test battery consists of well-established, non-invasive tests, which are performed on the face, hand or foot of the participants. The tests measure parameters which reflect nearly all aspects of somatosensation (thermal detection thresholds, thermal pain thresholds, mechanical detection thresholds for touch, mechanical pain threshold, mechanical allodynia, vibration detection threshold and pressure pain threshold). | One time assessment with a duration of max. 60 minutes. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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thalamic pain, thalamic stroke, chronic pain, sensory abnormalities, pain disorder, migraine