<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03019432</url>
  </required_header>
  <id_info>
    <org_study_id>Saeys-2</org_study_id>
    <nct_id>NCT03019432</nct_id>
  </id_info>
  <brief_title>Perception of Verticality After Stroke</brief_title>
  <official_title>The Effect of Sensory Loss on the E-effect in Post-stroke Patients. A New Insight in Sensory Weighting Strategies</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Universiteit Antwerpen</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Universiteit Antwerpen</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      In this study, the researchers will investigate whether the E-effect is present in stroke&#xD;
      subjects both on the subjective visual and postural vertical test. In addition, researchers&#xD;
      will investigate the impact of the loss of different sensory information sources on the&#xD;
      sensory reweighting strategies and perception of verticality by measuring the effect of&#xD;
      somatosensory loss on the E-effect.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Postural control emerges from the interaction between the task, the environment and the&#xD;
      individual. Within the individual, an efficient interaction between motor, sensory and neural&#xD;
      systems is needed in order to maintain postural control.(1) One of the neural processes is&#xD;
      the integration of afferent information such as visual, vestibular and somatosensory input to&#xD;
      construct a body-centred frame of reference in the gravitational environment.(2) This frame&#xD;
      of reference must be vertically aligned with the gravitational vector to ensure axial&#xD;
      extension of the body keeping the centre of gravity within the base of support.&#xD;
&#xD;
      Each of the sensory modalities has a relative load contribution in the estimation of&#xD;
      verticality depending on the task and the environment.(3) In healthy subjects, when certain&#xD;
      modalities are absent or information seems biased e.g. walking in complete darkness, more&#xD;
      weight is given to other sensory input sources.(1) This reweighting of sensory information is&#xD;
      therefore key in postural responses in humans.&#xD;
&#xD;
      However, sensory reweighting is not always adequate when certain modalities are biased. In&#xD;
      verticality perception, when the roll tilt of the head is less than 60°-70°, a contralateral&#xD;
      deviation of the subjective vertical has been reported.(4) This is called the E-effect and&#xD;
      has been observed in both the Subjective Visual Vertical test (SVV) and the Subjective&#xD;
      Postural Vertical test (SPV).(5, 6) Furthermore, studies have shown that also somatosensory&#xD;
      loss has a negative impact on perceiving verticality in patients after stroke.(7) In our&#xD;
      opinion, when less afferent input sources are present, adequate estimation of the earth&#xD;
      vertical will be more difficult. Since, studies show that verticality perception is highly&#xD;
      related to postural control(8, 9), this is of major importance. In neurological conditions&#xD;
      such as stroke sensory input sources are often affected, leading to fewer options in sensory&#xD;
      reweighting strategies.(10) In this study, the researchers will explore verticality&#xD;
      perception and sensory reweighting strategies in stroke subjects. At first, the researchers&#xD;
      will investigate whether the E-effect also occurs in our sample of stroke subjects. Secondly,&#xD;
      they will investigate the effect of somatosensory loss on the extent of the E-effect. It can&#xD;
      be hypothesized that when patients have no sensory loss, more secondary afferent input is&#xD;
      available to improve estimation of the vertical and therefore less misleading by the&#xD;
      head-on-body tilt.&#xD;
&#xD;
      Patients and methods Study design A cohort study was designed to investigate whether the&#xD;
      E-effect occurs in people after stroke. In addition, the effect of somatosensory loss on the&#xD;
      extent of the E-effect will be investigated to provide further insights in the sensory&#xD;
      reweighting strategies. Ethical approval was given by the ethical committee with registration&#xD;
      number B300201630358 in accordance with the Declaration of Helsinki 1975, revised Hong Kong&#xD;
      1989 Patients Patients were recruited from the stroke population of the rehabilitation&#xD;
      hospital Revarte, Antwerp, Belgium. All patients with a history of first stroke attending a&#xD;
      rehabilitation program were eligible for inclusion. Patients who had an age above 80; other&#xD;
      neurological and orthopaedic impairments as well as brainstem, cerebellar or multiple lesions&#xD;
      were excluded. Only strokes with an ischemic or hemorrhagic etiology were included. Patients&#xD;
      were also excluded when the subjects had pre-existing co-morbid conditions that may affect&#xD;
      vision and somatosensory function. In addition, patients with visuospatial neglect and pusher&#xD;
      behaviour were also excluded as this can affect verticality perception. This was examined by&#xD;
      a neuropsychologist and the use of the Scale of Contraversive Pushing (SCP)(11). In addition,&#xD;
      patients had to perform the assessment within three months post-stroke. Prior to inclusion,&#xD;
      the participants were asked whether they understand the instructions of tests and to sign a&#xD;
      written informed consent.&#xD;
&#xD;
      Outcome measures Rivermead assessment for somatosensory Performance The Rivermead Assessment&#xD;
      for Somatosensory Performance (RASP) measures different somatosensory modalities on the face,&#xD;
      hands and feet and has been noted to be a reliable and standardized assessment. Six tests are&#xD;
      administered on each of the ten (five left and five right) test regions on the face; hands&#xD;
      and feet, two tests are administered on only the face and palm of the hands. During testing&#xD;
      eyes of the participants are closed. These eight tests can be divided into six primary and&#xD;
      two secondary tests of sensation. Six trials are executed on each of the ten test regions,&#xD;
      for two of the tests sham trials were given. Sham trials increase the patient's internal&#xD;
      reliability. Patients were excluded from the statistical analysis if they had more than five&#xD;
      false positive replies, suggested by Winward et al.(12) Subjective Visual Vertical (SVV) The&#xD;
      Difra Vertitest type D107201 (Difra, Welkenraedt, Belgium) was used for SVV assessment. The&#xD;
      device has an accuracy of 0.1°. A laser bar is projected at a distance of 2.5m on an opposing&#xD;
      wall and on an altitude of 1.5m. The patients are seated in front of the device on a chair&#xD;
      without any arm- or backrests. Patients with no adequate sitting balance were assessed while&#xD;
      seated in their wheelchair. The room was darkened and five minutes of waiting period was&#xD;
      given allowing the subject to adjust the darkness. Both researcher and participant obtained a&#xD;
      remote to allow rotating the laser bar either clockwise (right) or counter clockwise (left).&#xD;
      The researcher's remote showed a display with the amount of deviation in relation to the&#xD;
      earth's gravitational vector. The researcher made the laser bar invisible and rotated it in a&#xD;
      specific angle in relation to the earth vertical. Subsequently, the line was shown after&#xD;
      which the patient had to place the line in upright position again with his nonhemiplegic hand&#xD;
      on the remote control. The amount of deviation of each starting roll position was different&#xD;
      for each trial. A specified order was followed: first the line was placed in 20° counter&#xD;
      clockwise, 10° clockwise, 5° counter clockwise and 0° according to the earth vertical,&#xD;
      followed by 5° clockwise, 10° counter clockwise and finally 20° clockwise. This series was&#xD;
      executed three times. During the first series the patient was asked to hold the head in&#xD;
      normal upright position, followed by a series with the head tilted to the left (while the&#xD;
      head was bent the subjects needed to keep their trunk upright) and finally a series with the&#xD;
      head tilted to the right side. The clockwise rotation is shown positively and the counter&#xD;
      clockwise negatively. The patients did not receive any feedback about their performance&#xD;
      during assessment.&#xD;
&#xD;
      Subjective Postural Vertical (SPV) The rotation chair works on hydraulic pumps and has a&#xD;
      height of 1m. On the back of the chair, a Mitutoyo digital protractor pro 3600 (Belgium) was&#xD;
      mounted. This allowed measurement of the deviation in relation to the earth vertical with an&#xD;
      accuracy of 0.01°. Both the researcher and patient were given a remote to rotate the chair&#xD;
      clockwise (right) and counter clockwise (left). Movements were restricted in the frontal&#xD;
      plane. Before the assessment started the patient was blindfolded, depriving the subjects of&#xD;
      visual information when readjusting the chair to earth vertical. The researcher rotated the&#xD;
      chair as in the procedure of SVV (starting roll position of the chair). The head-on-body&#xD;
      position is similar as in the SVV procedure. The subject had to place the chair in upright&#xD;
      position again by placing the seating surface of the chair horizontal. The patient used his&#xD;
      non-hemiplegic hand on the remote control. The clockwise rotation is shown positively and the&#xD;
      counter clockwise rotation negatively.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Recruiting</last_known_status>
  <start_date>January 2017</start_date>
  <completion_date type="Anticipated">February 2017</completion_date>
  <primary_completion_date type="Anticipated">February 2017</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Cross-Sectional</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Rivermead Assessment of Somatosensory Performance</measure>
    <time_frame>1 day</time_frame>
    <description>This test assesses several modalities of somatosensory performance such as sharp/dull discrimination; warm/cold; proprioception; 2-point discrimination.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Subjective Visual Vertical Test (SVV)</measure>
    <time_frame>1 day</time_frame>
    <description>This test measures the ability of the subject to realign a laser bar with the earth vertical after the malalignment procedure. This test occurs in complete darkness to inhibit visual references. The device used for the projection is the Vertitest (Difra, Belgium).</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Subjective Postural Vertical Test</measure>
    <time_frame>1 day</time_frame>
    <description>This test measures the ability of the subject to realign a chair, at which the subject is seated, with the earth vertical after a malalignment procedure. This test occurs blindfolded to inhibit visual references. The tilting chair used for this test is custom made. The deviation/error of the realigned chair compared to the earth vertical is measured by a digital protractor.</description>
  </primary_outcome>
  <enrollment type="Anticipated">40</enrollment>
  <condition>Sensory Disorder</condition>
  <condition>Stroke</condition>
  <condition>Cerebrovascular Disorders</condition>
  <intervention>
    <intervention_type>Behavioral</intervention_type>
    <intervention_name>Observational clinical assessment</intervention_name>
    <description>perception of verticality measures SVV and SPV; somatosensory assessment RASP</description>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        stroke patients within 3 months poststroke hospitalized in a Belgian Rehabilitation&#xD;
        Hospital&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion criteria:&#xD;
&#xD;
          -  Adult first-stroke patients&#xD;
&#xD;
          -  Maximum 3 months post-stroke at inclusion&#xD;
&#xD;
          -  Patients attending a rehabilitation program in the Rehabilitation Hospital Revarte,&#xD;
             Belgium&#xD;
&#xD;
        Exclusion criteria:&#xD;
&#xD;
          -  An age above 65&#xD;
&#xD;
          -  Neurological, except stroke, and orthopaedic impairments influencing outcome measures&#xD;
&#xD;
          -  Brainstem, cerebellar or multiple lesions&#xD;
&#xD;
          -  An ischemic or hemorrhagic etiology&#xD;
&#xD;
          -  Pre-existing co-morbid conditions that may affect vision and somatosensory function&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>65 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Wim Saeys, Dr</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of Antwerp, Belgium</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Wim Saeys, Dr</last_name>
    <phone>0032496804347</phone>
    <email>wim.saeys@uantwerpen.be</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Steven truijen, Prof</last_name>
    <phone>003232652297</phone>
    <email>steven.truijen@uantwerpen.be</email>
  </overall_contact_backup>
  <location>
    <facility>
      <name>Rehabilitation Hospital Revarte</name>
      <address>
        <city>Wilrijk</city>
        <state>Antwerp</state>
        <zip>2650</zip>
        <country>Belgium</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Wim Saeys, Dr.</last_name>
      <phone>496804347</phone>
      <email>wim.saeys@uantwerpen.be</email>
    </contact>
    <contact_backup>
      <last_name>Steven Truijen, Prof Dr.</last_name>
      <email>Steven.truijen@uantwerpen.be</email>
    </contact_backup>
  </location>
  <location_countries>
    <country>Belgium</country>
  </location_countries>
  <verification_date>January 2017</verification_date>
  <study_first_submitted>January 9, 2017</study_first_submitted>
  <study_first_submitted_qc>January 10, 2017</study_first_submitted_qc>
  <study_first_posted type="Estimate">January 12, 2017</study_first_posted>
  <last_update_submitted>January 16, 2017</last_update_submitted>
  <last_update_submitted_qc>January 16, 2017</last_update_submitted_qc>
  <last_update_posted type="Estimate">January 18, 2017</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Universiteit Antwerpen</investigator_affiliation>
    <investigator_full_name>Wim Saeys</investigator_full_name>
    <investigator_title>Dr</investigator_title>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Stroke</mesh_term>
    <mesh_term>Cerebrovascular Disorders</mesh_term>
    <mesh_term>Sensation Disorders</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>Undecided</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03019432
org study id: Saeys-2
nct id: NCT03019432
lead sponsor: 
has dmc: No
In this study, the researchers will investigate whether the E-effect is present in stroke
      subjects both on the subjective visual and postural vertical test. In addition, researchers
      will investigate the impact of the loss of different sensory information sources on the
      sensory reweighting strategies and perception of verticality by measuring the effect of
      somatosensory loss on the E-effect.
Postural control emerges from the interaction between the task, the environment and the
      individual. Within the individual, an efficient interaction between motor, sensory and neural
      systems is needed in order to maintain postural control.(1) One of the neural processes is
      the integration of afferent information such as visual, vestibular and somatosensory input to
      construct a body-centred frame of reference in the gravitational environment.(2) This frame
      of reference must be vertically aligned with the gravitational vector to ensure axial
      extension of the body keeping the centre of gravity within the base of support.

      Each of the sensory modalities has a relative load contribution in the estimation of
      verticality depending on the task and the environment.(3) In healthy subjects, when certain
      modalities are absent or information seems biased e.g. walking in complete darkness, more
      weight is given to other sensory input sources.(1) This reweighting of sensory information is
      therefore key in postural responses in humans.

      However, sensory reweighting is not always adequate when certain modalities are biased. In
      verticality perception, when the roll tilt of the head is less than 60°-70°, a contralateral
      deviation of the subjective vertical has been reported.(4) This is called the E-effect and
      has been observed in both the Subjective Visual Vertical test (SVV) and the Subjective
      Postural Vertical test (SPV).(5, 6) Furthermore, studies have shown that also somatosensory
      loss has a negative impact on perceiving verticality in patients after stroke.(7) In our
      opinion, when less afferent input sources are present, adequate estimation of the earth
      vertical will be more difficult. Since, studies show that verticality perception is highly
      related to postural control(8, 9), this is of major importance. In neurological conditions
      such as stroke sensory input sources are often affected, leading to fewer options in sensory
      reweighting strategies.(10) In this study, the researchers will explore verticality
      perception and sensory reweighting strategies in stroke subjects. At first, the researchers
      will investigate whether the E-effect also occurs in our sample of stroke subjects. Secondly,
      they will investigate the effect of somatosensory loss on the extent of the E-effect. It can
      be hypothesized that when patients have no sensory loss, more secondary afferent input is
      available to improve estimation of the vertical and therefore less misleading by the
      head-on-body tilt.

      Patients and methods Study design A cohort study was designed to investigate whether the
      E-effect occurs in people after stroke. In addition, the effect of somatosensory loss on the
      extent of the E-effect will be investigated to provide further insights in the sensory
      reweighting strategies. Ethical approval was given by the ethical committee with registration
      number B300201630358 in accordance with the Declaration of Helsinki 1975, revised Hong Kong
      1989 Patients Patients were recruited from the stroke population of the rehabilitation
      hospital Revarte, Antwerp, Belgium. All patients with a history of first stroke attending a
      rehabilitation program were eligible for inclusion. Patients who had an age above 80; other
      neurological and orthopaedic impairments as well as brainstem, cerebellar or multiple lesions
      were excluded. Only strokes with an ischemic or hemorrhagic etiology were included. Patients
      were also excluded when the subjects had pre-existing co-morbid conditions that may affect
      vision and somatosensory function. In addition, patients with visuospatial neglect and pusher
      behaviour were also excluded as this can affect verticality perception. This was examined by
      a neuropsychologist and the use of the Scale of Contraversive Pushing (SCP)(11). In addition,
      patients had to perform the assessment within three months post-stroke. Prior to inclusion,
      the participants were asked whether they understand the instructions of tests and to sign a
      written informed consent.

      Outcome measures Rivermead assessment for somatosensory Performance The Rivermead Assessment
      for Somatosensory Performance (RASP) measures different somatosensory modalities on the face,
      hands and feet and has been noted to be a reliable and standardized assessment. Six tests are
      administered on each of the ten (five left and five right) test regions on the face; hands
      and feet, two tests are administered on only the face and palm of the hands. During testing
      eyes of the participants are closed. These eight tests can be divided into six primary and
      two secondary tests of sensation. Six trials are executed on each of the ten test regions,
      for two of the tests sham trials were given. Sham trials increase the patient's internal
      reliability. Patients were excluded from the statistical analysis if they had more than five
      false positive replies, suggested by Winward et al.(12) Subjective Visual Vertical (SVV) The
      Difra Vertitest type D107201 (Difra, Welkenraedt, Belgium) was used for SVV assessment. The
      device has an accuracy of 0.1°. A laser bar is projected at a distance of 2.5m on an opposing
      wall and on an altitude of 1.5m. The patients are seated in front of the device on a chair
      without any arm- or backrests. Patients with no adequate sitting balance were assessed while
      seated in their wheelchair. The room was darkened and five minutes of waiting period was
      given allowing the subject to adjust the darkness. Both researcher and participant obtained a
      remote to allow rotating the laser bar either clockwise (right) or counter clockwise (left).
      The researcher's remote showed a display with the amount of deviation in relation to the
      earth's gravitational vector. The researcher made the laser bar invisible and rotated it in a
      specific angle in relation to the earth vertical. Subsequently, the line was shown after
      which the patient had to place the line in upright position again with his nonhemiplegic hand
      on the remote control. The amount of deviation of each starting roll position was different
      for each trial. A specified order was followed: first the line was placed in 20° counter
      clockwise, 10° clockwise, 5° counter clockwise and 0° according to the earth vertical,
      followed by 5° clockwise, 10° counter clockwise and finally 20° clockwise. This series was
      executed three times. During the first series the patient was asked to hold the head in
      normal upright position, followed by a series with the head tilted to the left (while the
      head was bent the subjects needed to keep their trunk upright) and finally a series with the
      head tilted to the right side. The clockwise rotation is shown positively and the counter
      clockwise negatively. The patients did not receive any feedback about their performance
      during assessment.

      Subjective Postural Vertical (SPV) The rotation chair works on hydraulic pumps and has a
      height of 1m. On the back of the chair, a Mitutoyo digital protractor pro 3600 (Belgium) was
      mounted. This allowed measurement of the deviation in relation to the earth vertical with an
      accuracy of 0.01°. Both the researcher and patient were given a remote to rotate the chair
      clockwise (right) and counter clockwise (left). Movements were restricted in the frontal
      plane. Before the assessment started the patient was blindfolded, depriving the subjects of
      visual information when readjusting the chair to earth vertical. The researcher rotated the
      chair as in the procedure of SVV (starting roll position of the chair). The head-on-body
      position is similar as in the SVV procedure. The subject had to place the chair in upright
      position again by placing the seating surface of the chair horizontal. The patient used his
      non-hemiplegic hand on the remote control. The clockwise rotation is shown positively and the
      counter clockwise rotation negatively.
observational model: Cohort
time perspective: Cross-Sectional
measure: Rivermead Assessment of Somatosensory Performance
time frame: 1 day
description: This test assesses several modalities of somatosensory performance such as sharp/dull discrimination; warm/cold; proprioception; 2-point discrimination.
measure: Subjective Visual Vertical Test (SVV)
time frame: 1 day
description: This test measures the ability of the subject to realign a laser bar with the earth vertical after the malalignment procedure. This test occurs in complete darkness to inhibit visual references. The device used for the projection is the Vertitest (Difra, Belgium).
measure: Subjective Postural Vertical Test
time frame: 1 day
description: This test measures the ability of the subject to realign a chair, at which the subject is seated, with the earth vertical after a malalignment procedure. This test occurs blindfolded to inhibit visual references. The tilting chair used for this test is custom made. The deviation/error of the realigned chair compared to the earth vertical is measured by a digital protractor.
intervention type: Behavioral
intervention name: Observational clinical assessment
description: perception of verticality measures SVV and SPV; somatosensory assessment RASP
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: 65 Years
healthy volunteers: No
last name: Wim Saeys, Dr
role: Principal Investigator
affiliation: University of Antwerp, Belgium
last name: Wim Saeys, Dr
phone: 0032496804347
email: wim.saeys@uantwerpen.be
last name: Steven truijen, Prof
phone: 003232652297
email: steven.truijen@uantwerpen.be
facility: 
status: Recruiting
contact: 
contact backup: 
country: Belgium
responsible party type: Principal Investigator
investigator affiliation: Universiteit Antwerpen
investigator full name: Wim Saeys
investigator title: Dr
mesh term: Stroke
mesh term: Cerebrovascular Disorders
mesh term: Sensation Disorders
sharing ipd: Undecided