Clinical trial NCT02185313: Gaze Holding in Cerebellar Patients
Official title: Verticality Perception and Gaze Holding in Healthy Human Subjects and Patients With Acute and Chronic Cerebellar Disorders
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Gaze Holding in Humans
Rebound in Humans
Lead sponsor: University of Zurich
Sponsor class: OTHER
First posted: 2014-07-09
Enrollment: 22
Sex: ALL
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: The long-term goal of this research is to advance the investigators knowledge of how the cerebellum a) controls gaze holding and compensates for impaired gaze stability and b) modulates vestibular information that is forward-ed from the labyrinth and brought to perception. While gaze holding is stable also at large angles of gaze eccentricity in healthy human subjects, patients with chronic (degenerative) cerebellar disorders are inable to stabilize gaze in eccentric positions, resulting in eye drift towards primary (straight-ahead) position and com-pensatory gaze-evoked nystagmus. When returning to primary position, a compensatory nystagmus into the opposite direction (called rebound nystagmus) can be observed in these patients. Unlike patients with de-generative cerebellar disorders, patients suffering from ischemic of hemorrhagic stroke within the cerebellum present with acute deficits of gaze holding and verticality perception.

While a linear relationship between the amount of eye velocity drift and eccentricity of eye position has been proposed in healthy human subjects, others suggested non-linear behaviour. The strategy of this research is to characterize gaze holding and verticality perception in healthy human subjects and patients with either acute (ischemic or hemorrhagic) or chronic degenerative cerebellar disorders and to relate eye movement findings with structural imaging of the cerebellum. The investigators will therefore analyze key cerebellar structures with regards to loss of volume and relate these imaging findings with the participants' ability to hold gaze and es-timate direction of vertical. The investigators hypothesize that besides the flocculus other vestibulo-cerebellar structures are involved in gaze holding and verticality perception in humans.


Eligibility criteria: Inclusion Criteria:

1. ages 18-85
2. informed consent
3. for group 1: acute (i.e. symptom onset \<14 days ago) cerebellar ischemia or hemorrhage as confirmed by clinical examination and brain imaging (CT or MRI)
4. for group 2: chronic cerebellar degeneration as confirmed by clinical examination (presence of downbeat-nystagmus and / or gaze-evoked nystagmus and / or ataxia of gait and stance) in the absence of focal lesions (as previous cerebellar stroke, mass lesion or inflammation) on clinical routine cerebellar imaging
5. absence of exclusion criteria

Exclusion Criteria:

1. has MRI contraindications such as pacemaker, implanted pumps, shrapnel, etc. (full MRI screening form will be filled out).
2. disturbed consciousness
3. other neurological or systemic disorder which can cause dementia or cognitive dysfunction
4. Pregnancy or possible pregnancy if not ruled out by a negative pregnancy test.

Primary outcomes:
measure: eye velocity in relation to eye position
timeFrame: during the visual stimulus (5min)
Secondary outcomes:
measure: symmetry of eye velocity for right vs. left gaze
timeFrame: during the visual stimulus (5min)
Other outcomes:
Locations:
city: Zurich
country: Switzerland
facility: University Hospital Zurich, Division of Neurology
state: ZH
Study officials:
affiliation: University Hospital Zurich, Division of Neurology
name: Dominik Straumann, Prof MD
role: PRINCIPAL_INVESTIGATOR
References: