Functional Link Between Hippocampal and Vestibular Systems: a Pilot Study in Epilepsy Surgery Principal Investigator: Elizabeth VITTE
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 22
- Locations
- 1
- Primary Endpoint
- caloric test
Study Overview
Brief Summary
Vestibular signals deeply influence hippocampal spatial representations and may contribute to the navigational deficits of humans with vestibular dysfunction. The reciprocal influence of hippocampal signals on the vestibular system are more putative. The investigators wish to investigate in this pilot study the consequences on vestibular system of the removal of the hippocampal formation to treat drug resistant temporal lobe epilepsy.
Detailed Description
Functional link between hippocampal and vestibular systems: a pilot study in epilepsy surgery
Hypothesis:
The human hippocampal formation plays a crucial role in various aspects of memory processing. Work in rodents and some other species emphasized the role of the hippocampus in spatial learning and memory as well. A few human studies also point to a direct relation between hippocampal size, navigation and spatial memory. Patients with acquired chronic bilateral vestibular loss develop a significant selective atrophy of the hippocampus (Brandt et al, 2005) and activation of lateral semicircular canal by caloric stimulation induces activation of hippocampal formation in f-MRI (VITTE et al, 1996). But the investigators still do not know the effects on vestibular responses of the removal of the hippocampal formation to cure temporal lobe epilepsy. If the hippocampal formation directly influences the vestibular response, an asymmetry of the vestibular responses should be recorded postoperatively.
Principal criterion Research for an asymmetry of the vestibular responses (Caloric test, Vestibular Evoked Myogenic potentials: VEMp, Head Impulse Test: HIT, Eye Rotational Test: ERI)
Inclusion criteria
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Diagnostic
- Masking
- Single (Investigator)
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •patients suffering of intractable mesial temporal lobe epilepsy and candidate for surgery,
- •without history of any cochlea-vestibular disorder
- •older than 18 years,
- •French residents,
- •with medicare,
- •after signed informed consent
Exclusion Criteria
- •History of cochlea-vestibular disorder
- •Pregnancy
Arms & Interventions
hippocampal surgery
Vestibular test before and after hippocampal surgery
Principal criterion:
Research for an asymmetry of the vestibular responses (Caloric test, Vestibular Evoked Myogenic potentials: VEMp, Head Impulse Test: HIT, Eye Rotational Test: ERI). Investigator performs a blind vestibular test (single blind)
Intervention: vestibular test before and after hippocampal surgery (Other)
Outcomes
Primary Outcomes
caloric test
Time Frame: 6 months after surgery
-Caloric test (testing lateral semicircular function at low frequency). Results: Canal paresis in % and SPV in °/S
Secondary Outcomes
- vestibular test(6 months after surgery)